chore: Bump version to v2.18.0

Bluetooth enhancements (service data inspector, appearance codes, MAC
cluster tracking, behavioral flags, IRK badges, distance estimation),
ACARS SoapySDR multi-backend support, dump1090 stale process cleanup,
GPS error state, and proximity radar/signal card UI improvements.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Dockerfile

@@ -41,6 +41,7 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
     bluez \
     bluetooth \
     # GPS support
+    gpsd \
     gpsd-clients \
     # Utilities
     # APRS

LICENSE

@@ -1,21 +1,200 @@
-MIT License
 
-Copyright (c) 2025 smittix
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+      the terms of any separate license agreement you may have executed
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+
+   6. Trademarks. This License does not grant permission to use the trade
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+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
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+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
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+      has been advised of the possibility of such damages.
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+   9. Accepting Warranty or Additional Liability. While redistributing
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+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
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+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
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README.md

@@ -28,19 +28,23 @@ Support the developer of this open-source project
 
 - **Pager Decoding** - POCSAG/FLEX via rtl_fm + multimon-ng
 - **433MHz Sensors** - Weather stations, TPMS, IoT devices via rtl_433
+- **Sub-GHz Analyzer** - RF capture and protocol decoding for 300-928 MHz ISM bands via HackRF
 - **Aircraft Tracking** - ADS-B via dump1090 with real-time map and radar
 - **Vessel Tracking** - AIS ship tracking with VHF DSC distress monitoring
 - **ACARS Messaging** - Aircraft datalink messages via acarsdec
-- **DMR Digital Voice** - DMR/P25/NXDN/D-STAR decoding via dsd-fme with visual synthesizer
+- **Listening Post** - Wideband frequency scanner with real-time audio monitoring
-- **Listening Post** - Frequency scanner with audio monitoring
+- **Weather Satellites** - NOAA APT and Meteor LRPT image decoding via SatDump with auto-scheduler
-- **Weather Satellites** - NOAA APT and Meteor LRPT image decoding via SatDump
+- **WebSDR** - Remote HF/shortwave listening via KiwiSDR network
-- **WebSDR** - Remote HF/shortwave listening via WebSDR servers
 - **ISS SSTV** - Slow-scan TV image reception from the International Space Station
-- **HF SSTV** - Terrestrial SSTV on shortwave frequencies
+- **HF SSTV** - Terrestrial SSTV on shortwave frequencies (80m-10m, VHF, UHF)
-- **Satellite Tracking** - Pass prediction using TLE data
+- **APRS** - Amateur packet radio position reports and telemetry via direwolf
+- **Satellite Tracking** - Pass prediction with polar plot and ground track map
+- **Utility Meters** - Electric, gas, and water meter reading via rtl_amr
 - **ADS-B History** - Persistent aircraft history with reporting dashboard (Postgres optional)
 - **WiFi Scanning** - Monitor mode reconnaissance via aircrack-ng
 - **Bluetooth Scanning** - Device discovery and tracker detection (with Ubertooth support)
+- **BT Locate** - SAR Bluetooth device location with GPS-tagged signal trail mapping and proximity alerts
+- **GPS** - Real-time GPS position tracking with live map, speed, altitude, and satellite info
 - **TSCM** - Counter-surveillance with RF baseline comparison and threat detection
 - **Meshtastic** - LoRa mesh network integration
 - **Spy Stations** - Number stations and diplomatic HF network database
@@ -224,7 +228,7 @@ This project was developed using AI as a coding partner, combining human directi
 
 ## License
 
-MIT License - see [LICENSE](LICENSE)
+Apache 2.0 License - see [LICENSE](LICENSE)
 
 ## Author
 
@@ -238,6 +242,8 @@ Created by **smittix** - [GitHub](https://github.com/smittix)
 [dump1090](https://github.com/flightaware/dump1090) |
 [AIS-catcher](https://github.com/jvde-github/AIS-catcher) |
 [acarsdec](https://github.com/TLeconte/acarsdec) |
+[direwolf](https://github.com/wb2osz/direwolf) |
+[rtl_amr](https://github.com/bemasher/rtlamr) |
 [aircrack-ng](https://www.aircrack-ng.org/) |
 [Leaflet.js](https://leafletjs.com/) |
 [SatDump](https://github.com/SatDump/SatDump) |
@@ -252,3 +258,4 @@ Created by **smittix** - [GitHub](https://github.com/smittix)
 
 
 
+

app.py

@@ -29,7 +29,7 @@ from flask import Flask, render_template, jsonify, send_file, Response, request,
 from werkzeug.security import check_password_hash
 from config import VERSION, CHANGELOG, SHARED_OBSERVER_LOCATION_ENABLED, DEFAULT_LATITUDE, DEFAULT_LONGITUDE
 from utils.dependencies import check_tool, check_all_dependencies, TOOL_DEPENDENCIES
-from utils.process import cleanup_stale_processes
+from utils.process import cleanup_stale_processes, cleanup_stale_dump1090
 from utils.sdr import SDRFactory
 from utils.cleanup import DataStore, cleanup_manager
 from utils.constants import (
@@ -877,6 +877,7 @@ def main() -> None:
 
     # Clean up any stale processes from previous runs
     cleanup_stale_processes()
+    cleanup_stale_dump1090()
 
     # Initialize database for settings storage
     from utils.database import init_db

config.py

@@ -7,10 +7,32 @@ import os
 import sys
 
 # Application version
-VERSION = "2.16.0"
+VERSION = "2.18.0"
 
 # Changelog - latest release notes (shown on welcome screen)
 CHANGELOG = [
+    {
+        "version": "2.18.0",
+        "date": "February 2026",
+        "highlights": [
+            "Bluetooth: service data inspector, appearance codes, MAC cluster tracking, and behavioral flags",
+            "Bluetooth: IRK badge display, distance estimation with confidence, and signal stability metrics",
+            "ACARS: SoapySDR device support for SDRplay, LimeSDR, Airspy, and other non-RTL backends",
+            "ADS-B: stale dump1090 process cleanup via PID file tracking",
+            "GPS: error state indicator and UI refinements",
+            "Proximity radar and signal card UI improvements",
+        ]
+    },
+    {
+        "version": "2.17.0",
+        "date": "February 2026",
+        "highlights": [
+            "BT Locate: SAR Bluetooth device location with GPS-tagged signal trail and proximity alerts",
+            "IRK auto-detection: extract Identity Resolving Keys from paired devices (macOS/Linux)",
+            "GPS mode: real-time position tracking with live map, speed, altitude, and satellite info",
+            "Bluetooth scanner lifecycle fix for bleak scan timeout tracking",
+        ]
+    },
     {
         "version": "2.16.0",
         "date": "February 2026",
@@ -18,7 +40,6 @@ CHANGELOG = [
             "Sub-GHz analyzer with real-time RF capture and protocol decoding",
             "Weather satellite auto-scheduler with polar plot and ground track map",
             "SatDump support for local (non-Docker) installs via setup.sh",
-            "DMR audio output, frequency persistence, and bookmarks",
             "Shared waterfall UI across SDR modes",
             "Listening post audio stuttering fix and SDR race condition fixes",
             "Multi-arch Docker build support (amd64 + arm64)",

docs/FEATURES.md

@@ -16,6 +16,14 @@ Complete feature list for all modules.
 - **Doorbells, remotes, and IoT devices**
 - **Smart meters** and utility monitors
 
+## Sub-GHz Analyzer
+
+- **HackRF-based** signal capture and analysis for 300-928 MHz ISM bands
+- **Protocol decoding** - identify and decode common Sub-GHz protocols
+- **Signal replay/transmit** capabilities for authorized testing
+- **Wideband spectrum analysis** with real-time visualization
+- **I/Q capture** - record raw samples for offline analysis
+
 ## AIS Vessel Tracking
 
 - **Real-time vessel tracking** via AIS-catcher on 161.975/162.025 MHz
@@ -84,6 +92,55 @@ Digital Selective Calling (DSC) monitoring on the international maritime distres
 - **SDR conflict detection** - Prevents device collisions with AIS tracking
 - **Alert summary** - Dashboard counts for unacknowledged distress/urgency
 
+## ACARS Messaging
+
+- **Real-time ACARS decoding** via acarsdec
+- **Aircraft datalink messages** - operational, weather, and position reports
+- **Multi-SDR support** - RTL-SDR, HackRF, LimeSDR, Airspy, SDRplay
+- **Message filtering** - filter by message type, flight, or registration
+
+## Listening Post
+
+- **Wideband frequency scanning** via rtl_power sweep with SNR filtering
+- **Real-time audio monitoring** with FM and SSB demodulation
+- **Cross-module frequency routing** from scanner to decoders
+- **Customizable frequency presets** and band bookmarks
+- **Multi-SDR support** - RTL-SDR, LimeSDR, HackRF, Airspy, SDRplay
+
+## Weather Satellites
+
+- **NOAA APT** and **Meteor LRPT** image decoding via SatDump
+- **Auto-scheduler** with pass prediction and automatic capture
+- **Polar plot** - real-time satellite position on azimuth/elevation display
+- **Ground track map** - orbit path with past/future trajectory
+- **Image gallery** with timestamped decoded imagery
+
+## WebSDR
+
+- **KiwiSDR network integration** for remote HF/shortwave listening
+- **WebSocket audio streaming** from remote receivers
+- **Receiver discovery** with automatic caching
+- **Frequency tuning** with band presets
+
+## HF SSTV
+
+- **Terrestrial SSTV decoding** across HF (80m-10m), VHF (6m, 2m), and UHF (70cm) bands
+- **Predefined frequency lookup** for active SSTV calling frequencies
+- **Image gallery** with decoded transmissions
+
+## APRS
+
+- **Amateur packet radio** position reports and telemetry via direwolf
+- **Region-specific frequencies** - 144.390 MHz (North America), 144.800 MHz (Europe), and more
+- **Real-time position tracking** on interactive map
+- **Message and telemetry display** from APRS network
+
+## Utility Meter Reading
+
+- **Smart meter monitoring** via rtl_amr for electric, gas, and water meters
+- **Real-time JSON output** with meter ID, consumption, and signal data
+- **Multiple meter protocol support** via rtl_tcp integration
+
 ## Satellite Tracking
 
 - **Full-screen dashboard** - dedicated popout with polar plot and ground track
@@ -131,6 +188,52 @@ Digital Selective Calling (DSC) monitoring on the international maritime distres
 - **Proximity radar** visualization
 - **Device type breakdown** chart
 
+## BT Locate (SAR Bluetooth Device Location)
+
+Search and rescue Bluetooth device location with GPS-tagged signal trail mapping.
+
+### Core Features
+- **Target tracking** - Locate devices by MAC address, name pattern, or IRK (Identity Resolving Key)
+- **RPA resolution** - Resolve BLE Resolvable Private Addresses using IRK for tracking devices with randomized addresses
+- **IRK auto-detection** - Extract IRKs from paired devices on macOS and Linux
+- **GPS-tagged signal trail** - Every detection is tagged with GPS coordinates for trail mapping
+- **Proximity bands** - IMMEDIATE (<1m), NEAR (1-5m), FAR (>5m) with color-coded HUD
+- **RSSI history chart** - Real-time signal strength sparkline for trend analysis
+- **Distance estimation** - Log-distance path loss model with environment presets
+- **Audio proximity alerts** - Web Audio API tones that increase in pitch as signal strengthens
+- **Hand-off from Bluetooth mode** - One-click transfer of a device from BT scanner to BT Locate
+
+### Environment Presets
+- **Open Field** (n=2.0) - Free space path loss
+- **Outdoor** (n=2.2) - Typical outdoor environment
+- **Indoor** (n=3.0) - Indoor with walls and obstacles
+
+### Map & Trail
+- Interactive Leaflet map with GPS trail visualization
+- Trail points color-coded by proximity band
+- Polyline connecting detection points for path visualization
+- Supports user-configured tile providers
+
+### Requirements
+- Bluetooth adapter (built-in or USB)
+- GPS receiver (optional, falls back to manual coordinates)
+
+## GPS Mode
+
+Real-time GPS position tracking with live map visualization.
+
+### Features
+- **Live position tracking** - Real-time latitude, longitude, altitude display
+- **Interactive map** - Current position on Leaflet map with track history
+- **Speed and heading** - Real-time speed (km/h) and compass heading
+- **Satellite info** - Number of satellites in view and fix quality
+- **Track recording** - Record GPS tracks with export capability
+- **Accuracy display** - Horizontal and vertical position accuracy (EPX/EPY)
+
+### Requirements
+- USB GPS receiver connected via gpsd
+- gpsd daemon running (`sudo gpsd /dev/ttyUSB0 -F /var/run/gpsd.sock`)
+
 ## TSCM Counter-Surveillance Mode
 
 Technical Surveillance Countermeasures (TSCM) screening for detecting wireless surveillance indicators.

docs/USAGE.md

@@ -57,6 +57,32 @@ INTERCEPT automatically detects known trackers:
 - Samsung SmartTag
 - Chipolo
 
+## Sub-GHz Analyzer
+
+1. **Connect HackRF** - Plug in your HackRF One device
+2. **Set Frequency** - Enter a frequency in the 300-928 MHz ISM range or use a preset
+3. **Start Capture** - Click "Start Capture" to begin signal analysis
+4. **View Spectrum** - Real-time spectrum visualization of the selected band
+5. **Protocol Decoding** - Identified protocols are displayed with decoded data
+
+### Supported Protocols
+
+Common ISM band protocols including garage doors, key fobs, weather stations, and IoT devices in the 300-928 MHz range.
+
+## Listening Post
+
+1. **Select Hardware** - Choose your SDR type
+2. **Set Frequency Range** - Define start and end frequencies for scanning
+3. **Start Scanning** - Click "Start Scan" for wideband sweep
+4. **View Signals** - Discovered signals are listed with frequency and SNR
+5. **Tune In** - Click a signal to tune the audio demodulator
+6. **Listen** - Real-time audio plays in your browser
+
+### Demodulation Modes
+
+- **FM** - Narrowband and wideband FM
+- **SSB** - Upper and lower sideband for amateur radio and shortwave
+
 ## Aircraft Mode (ADS-B)
 
 1. **Select Hardware** - Choose your SDR type (RTL-SDR uses dump1090, others use readsb)
@@ -165,6 +191,106 @@ If the History dashboard shows **HISTORY DISABLED**, enable `INTERCEPT_ADSB_HIST
 3. Choose a category (Amateur, Weather, ISS, Starlink, etc.)
 4. Select satellites to add
 
+## Weather Satellites
+
+1. **Set Location** - Enter observer coordinates or use GPS
+2. **Select Satellite** - Choose NOAA (APT) or Meteor (LRPT)
+3. **View Passes** - Upcoming passes shown with polar plot and ground track
+4. **Start Capture** - Click "Start Capture" when a satellite is overhead, or enable auto-scheduler
+5. **View Images** - Decoded imagery appears in the gallery
+
+### Auto-Scheduler
+
+Enable the auto-scheduler to automatically capture passes:
+- Calculates upcoming NOAA and Meteor passes for your location
+- Starts SatDump at the correct time and frequency
+- Decoded images are saved with timestamps
+
+## AIS Vessel Tracking
+
+1. **Select Hardware** - Choose your SDR type
+2. **Start Tracking** - Click "Start Tracking" to monitor AIS frequencies (161.975/162.025 MHz)
+3. **View Map** - Vessels appear on the interactive maritime map
+4. **Click Vessels** - View name, MMSI, callsign, destination, speed, heading
+5. **Full Dashboard** - Click "Full Screen Dashboard" for dedicated maritime view
+
+### VHF DSC Channel 70
+
+Digital Selective Calling monitoring runs alongside AIS:
+- Distress, Urgency, Safety, and Routine messages
+- Distress positions plotted with pulsing alert markers
+- Audio alerts for critical messages
+
+## APRS
+
+1. **Select Hardware** - Choose your SDR type
+2. **Set Frequency** - Defaults to regional APRS frequency (144.390 MHz NA, 144.800 MHz EU)
+3. **Start Decoding** - Click "Start Decoding" to begin packet radio reception via direwolf
+4. **View Map** - Station positions appear on the interactive map
+5. **View Messages** - Position reports, telemetry, and messages displayed in real time
+
+## Utility Meters
+
+1. **Start Monitoring** - Click "Start" to begin meter broadcast reception via rtl_amr
+2. **View Meters** - Decoded meter data appears with meter ID, type, and consumption
+3. **Filter** - Filter by meter type (electric, gas, water) or meter ID
+
+## BT Locate (SAR Device Location)
+
+1. **Set Target** - Enter one or more target identifiers:
+   - **MAC Address** - Exact Bluetooth address (AA:BB:CC:DD:EE:FF)
+   - **Name Pattern** - Substring match (e.g., "iPhone", "Galaxy")
+   - **IRK** - 32-character hex Identity Resolving Key for RPA resolution
+   - **Detect IRKs** - Click "Detect" to auto-extract IRKs from paired devices
+2. **Choose Environment** - Select the RF environment preset:
+   - **Open Field** (n=2.0) - Best for open areas with line-of-sight
+   - **Outdoor** (n=2.2) - Default, works well in most outdoor settings
+   - **Indoor** (n=3.0) - For buildings with walls and obstacles
+3. **Start Locate** - Click "Start Locate" to begin tracking
+4. **Monitor HUD** - The proximity display shows:
+   - Proximity band (IMMEDIATE / NEAR / FAR)
+   - Estimated distance in meters
+   - Raw RSSI and smoothed RSSI average
+   - Detection count and GPS-tagged points
+5. **Follow the Signal** - Move towards stronger signal (higher RSSI / closer distance)
+6. **Audio Alerts** - Enable audio for proximity tones that increase in pitch as you get closer
+7. **Review Trail** - Check the map for GPS-tagged detection trail
+
+### Hand-off from Bluetooth Mode
+
+1. Open Bluetooth scanning mode and find the target device
+2. Click the "Locate" button on the device card
+3. BT Locate opens with the device pre-filled
+4. Click "Start Locate" to begin tracking
+
+### Tips
+
+- For devices with address randomization (iPhones, modern Android), use the IRK method
+- Click "Detect" next to the IRK field to auto-extract IRKs from paired devices
+- The RSSI chart shows signal trend over time — use it to determine if you're getting closer
+- Clear the trail when starting a new search area
+
+## GPS Mode
+
+1. **Start GPS** - Click "Start" to connect to gpsd and begin position tracking
+2. **View Map** - Your position appears on the interactive map with a track trail
+3. **Monitor Stats** - Speed, heading, altitude, and satellite count displayed in real-time
+4. **Record Track** - Enable track recording to save your path
+
+### Tips
+
+- Ensure gpsd is running: `sudo gpsd /dev/ttyUSB0 -F /var/run/gpsd.sock`
+- GPS fix may take 30-60 seconds after cold start
+- Accuracy improves with more satellites in view
+
+## Meshtastic
+
+1. **Connect Device** - Plug in a Meshtastic device via USB or connect via TCP
+2. **Start** - Click "Start" to connect to the mesh network
+3. **View Messages** - Real-time message stream from the mesh
+4. **View Nodes** - Connected nodes displayed with signal metrics (RSSI, SNR)
+5. **Send Messages** - Type messages to broadcast on the mesh
+
 ## Remote Agents (Distributed SIGINT)
 
 Deploy lightweight sensor nodes across multiple locations and aggregate data to a central controller.

docs/index.html

@@ -35,7 +35,7 @@
             </div>
             <div class="hero-stats">
                 <div class="stat">
-                    <span class="stat-value">15+</span>
+                    <span class="stat-value">20+</span>
                     <span class="stat-label">Modes</span>
                 </div>
                 <div class="stat">
@@ -77,6 +77,12 @@
                     <p>Decode 200+ protocols including weather stations, TPMS, smart home devices, and IoT sensors via rtl_433.</p>
                 </div>
 
+                <div class="feature-card">
+                    <div class="feature-icon">📻</div>
+                    <h3>Sub-GHz Analyzer</h3>
+                    <p>HackRF-based signal capture and protocol decoding for 300-928 MHz ISM bands with spectrum analysis and replay.</p>
+                </div>
+
                 <div class="feature-card">
                     <div class="feature-icon">📻</div>
                     <h3>Listening Post</h3>
@@ -101,6 +107,18 @@
                     <p>Device discovery with tracker detection for AirTags, Tile, Samsung SmartTag, and other Bluetooth devices.</p>
                 </div>
 
+                <div class="feature-card">
+                    <div class="feature-icon">📍</div>
+                    <h3>BT Locate</h3>
+                    <p>SAR Bluetooth device location with GPS-tagged signal trail mapping, IRK-based RPA resolution, and proximity audio alerts.</p>
+                </div>
+
+                <div class="feature-card">
+                    <div class="feature-icon">🛰️</div>
+                    <h3>GPS Tracking</h3>
+                    <p>Real-time GPS position tracking with live map, speed, heading, altitude, satellite info, and track recording.</p>
+                </div>
+
                 <div class="feature-card">
                     <div class="feature-icon">🛡️</div>
                     <h3>TSCM</h3>
@@ -143,11 +161,47 @@
                     <p>LoRa mesh network integration. Connect to Meshtastic devices for decentralized, long-range communication monitoring.</p>
                 </div>
 
+                <div class="feature-card">
+                    <div class="feature-icon">🌧️</div>
+                    <h3>Weather Satellites</h3>
+                    <p>NOAA APT and Meteor LRPT image decoding via SatDump with auto-scheduler, polar plot, and ground track map.</p>
+                </div>
+
                 <div class="feature-card">
                     <div class="feature-icon">🖼️</div>
                     <h3>ISS SSTV</h3>
                     <p>Receive Slow Scan Television from the ISS. Real-time tracking globe, pass predictions, and image decoding.</p>
                 </div>
+
+                <div class="feature-card">
+                    <div class="feature-icon">🖼️</div>
+                    <h3>HF SSTV</h3>
+                    <p>Terrestrial SSTV on shortwave frequencies. Decode amateur radio image transmissions across HF, VHF, and UHF bands.</p>
+                </div>
+
+                <div class="feature-card">
+                    <div class="feature-icon">✈️</div>
+                    <h3>ACARS</h3>
+                    <p>Aircraft datalink messages via acarsdec. Decode operational, weather, and position reports from commercial flights.</p>
+                </div>
+
+                <div class="feature-card">
+                    <div class="feature-icon">📍</div>
+                    <h3>APRS</h3>
+                    <p>Amateur packet radio position reports and telemetry via direwolf. Track amateur radio operators on an interactive map.</p>
+                </div>
+
+                <div class="feature-card">
+                    <div class="feature-icon">🌐</div>
+                    <h3>WebSDR</h3>
+                    <p>Remote HF/shortwave listening via the KiwiSDR network. Access receivers worldwide with real-time audio streaming.</p>
+                </div>
+
+                <div class="feature-card">
+                    <div class="feature-icon">⚡</div>
+                    <h3>Utility Meters</h3>
+                    <p>Smart meter monitoring via rtl_amr. Receive electric, gas, and water meter broadcasts in real time.</p>
+                </div>
             </div>
         </div>
     </section>
@@ -194,6 +248,10 @@
                     <img src="images/ais.png" alt="AIS Vessel Tracking">
                     <span class="screenshot-label">AIS Vessel Tracking</span>
                 </div>
+                <div class="screenshot-item">
+                    <img src="images/bt-locate.png" alt="BT Locate SAR Tracker">
+                    <span class="screenshot-label">BT Locate — SAR Tracker</span>
+                </div>
             </div>
         </div>
     </section>

intercept_agent.py

@@ -2022,7 +2022,7 @@ class ModeManager:
                     'agent_gps': gps_manager.position
                 }
 
-            scanner.set_on_device_updated(on_device_updated)
+            scanner.add_device_callback(on_device_updated)
 
             # Start scanning
             if scanner.start_scan(mode=mode_param, duration_s=duration):

pyproject.toml

@@ -1,10 +1,10 @@
 [project]
 name = "intercept"
-version = "2.16.0"
+version = "2.18.0"
 description = "Signal Intelligence Platform - Pager/433MHz/ADS-B/Satellite/WiFi/Bluetooth"
 readme = "README.md"
 requires-python = ">=3.9"
-license = {text = "MIT"}
+license = {text = "Apache-2.0"}
 authors = [
     {name = "Intercept Contributors"}
 ]
@@ -14,7 +14,7 @@ classifiers = [
     "Environment :: Web Environment",
     "Framework :: Flask",
     "Intended Audience :: Developers",
-    "License :: OSI Approved :: MIT License",
+    "License :: OSI Approved :: Apache Software License",
     "Operating System :: POSIX :: Linux",
     "Operating System :: MacOS",
     "Programming Language :: Python :: 3",

requirements.txt

@@ -32,6 +32,9 @@ scapy>=2.4.5
 # QR code generation for Meshtastic channels (optional)
 qrcode[pil]>=7.4
 
+# BLE RPA resolution for BT Locate (optional - for SAR device tracking)
+cryptography>=41.0.0
+
 # Development dependencies (install with: pip install -r requirements-dev.txt)
 # pytest>=7.0.0
 # pytest-cov>=4.0.0

routes/__init__.py

@@ -33,6 +33,7 @@ def register_blueprints(app):
     from .alerts import alerts_bp
     from .recordings import recordings_bp
     from .subghz import subghz_bp
+    from .bt_locate import bt_locate_bp
 
     app.register_blueprint(pager_bp)
     app.register_blueprint(sensor_bp)
@@ -65,6 +66,7 @@ def register_blueprints(app):
     app.register_blueprint(alerts_bp)  # Cross-mode alerts
     app.register_blueprint(recordings_bp)  # Session recordings
     app.register_blueprint(subghz_bp)  # SubGHz transceiver (HackRF)
+    app.register_blueprint(bt_locate_bp)  # BT Locate SAR device tracking
 
     # Initialize TSCM state with queue and lock from app
     import app as app_module

routes/acars.py

@@ -20,6 +20,7 @@ from flask import Blueprint, jsonify, request, Response
 import app as app_module
 from utils.logging import sensor_logger as logger
 from utils.validation import validate_device_index, validate_gain, validate_ppm
+from utils.sdr import SDRFactory, SDRType
 from utils.sse import format_sse
 from utils.event_pipeline import process_event
 from utils.constants import (
@@ -250,12 +251,22 @@ def start_acars() -> Response:
     acars_message_count = 0
     acars_last_message_time = None
 
+    # Resolve SDR type for device selection
+    sdr_type_str = data.get('sdr_type', 'rtlsdr')
+    try:
+        sdr_type = SDRType(sdr_type_str)
+    except ValueError:
+        sdr_type = SDRType.RTL_SDR
+
+    is_soapy = sdr_type not in (SDRType.RTL_SDR,)
+
     # Build acarsdec command
     # Different forks have different syntax:
     # - TLeconte v4+: acarsdec -j -g <gain> -p <ppm> -r <device> <freq1> <freq2> ...
     # - TLeconte v3: acarsdec -o 4 -g <gain> -p <ppm> -r <device> <freq1> <freq2> ...
     # - f00b4r0 (DragonOS): acarsdec --output json:file:- -g <gain> -p <ppm> -r <device> <freq1> ...
-    # Note: gain/ppm must come BEFORE -r
+    # SoapySDR devices: TLeconte uses -d <device_string>, f00b4r0 uses --soapysdr <device_string>
+    # Note: gain/ppm must come BEFORE -r/-d
     json_flag = get_acarsdec_json_flag(acarsdec_path)
     cmd = [acarsdec_path]
     if json_flag == '--output':
@@ -266,21 +277,33 @@ def start_acars() -> Response:
     else:
         cmd.extend(['-o', '4'])  # JSON output (TLeconte v3.x)
 
-    # Add gain if not auto (must be before -r)
+    # Add gain if not auto (must be before -r/-d)
     if gain and str(gain) != '0':
         cmd.extend(['-g', str(gain)])
 
-    # Add PPM correction if specified (must be before -r)
+    # Add PPM correction if specified (must be before -r/-d)
     if ppm and str(ppm) != '0':
         cmd.extend(['-p', str(ppm)])
 
     # Add device and frequencies
-    # f00b4r0 uses --rtlsdr <device>, TLeconte uses -r <device>
+    if is_soapy:
-    if json_flag == '--output':
+        # SoapySDR device (SDRplay, LimeSDR, Airspy, etc.)
+        sdr_device = SDRFactory.create_default_device(sdr_type, index=device_int)
+        # Build SoapySDR driver string (e.g., "driver=sdrplay,serial=...")
+        builder = SDRFactory.get_builder(sdr_type)
+        device_str = builder._build_device_string(sdr_device)
+        if json_flag == '--output':
+            cmd.extend(['-m', '256'])
+            cmd.extend(['--soapysdr', device_str])
+        else:
+            cmd.extend(['-d', device_str])
+    elif json_flag == '--output':
+        # f00b4r0 fork RTL-SDR: --rtlsdr <device>
         # Use 3.2 MS/s sample rate for wider bandwidth (handles NA frequency span)
         cmd.extend(['-m', '256'])
         cmd.extend(['--rtlsdr', str(device)])
     else:
+        # TLeconte fork RTL-SDR: -r <device>
         cmd.extend(['-r', str(device)])
     cmd.extend(frequencies)
 

routes/adsb.py

@@ -38,6 +38,7 @@ from config import (
     SHARED_OBSERVER_LOCATION_ENABLED,
 )
 from utils.logging import adsb_logger as logger
+from utils.process import write_dump1090_pid, clear_dump1090_pid, cleanup_stale_dump1090
 from utils.validation import (
     validate_device_index, validate_gain,
     validate_rtl_tcp_host, validate_rtl_tcp_port
@@ -633,6 +634,9 @@ def start_adsb():
             'session': session
         })
 
+    # Kill any stale app-spawned dump1090 from a previous run before checking the port
+    cleanup_stale_dump1090()
+
     # Check if dump1090 is already running externally (e.g., user started it manually)
     existing_service = check_dump1090_service()
     if existing_service:
@@ -685,6 +689,7 @@ def start_adsb():
             except (ProcessLookupError, OSError):
                 pass
         app_module.adsb_process = None
+        clear_dump1090_pid()
         logger.info("Killed stale ADS-B process")
 
     # Check if device is available before starting local dump1090
@@ -721,6 +726,7 @@ def start_adsb():
             stderr=subprocess.PIPE,
             start_new_session=True  # Create new process group for clean shutdown
         )
+        write_dump1090_pid(app_module.adsb_process.pid)
 
         time.sleep(DUMP1090_START_WAIT)
 
@@ -819,6 +825,7 @@ def stop_adsb():
                 except (ProcessLookupError, OSError):
                     pass
             app_module.adsb_process = None
+            clear_dump1090_pid()
             logger.info("ADS-B process stopped")
 
         # Release device from registry

routes/bluetooth_v2.py

@@ -229,7 +229,7 @@ def start_scan():
     rssi_threshold = data.get('rssi_threshold', -100)
 
     # Validate mode
-    valid_modes = ('auto', 'dbus', 'bleak', 'hcitool', 'bluetoothctl')
+    valid_modes = ('auto', 'dbus', 'bleak', 'hcitool', 'bluetoothctl', 'ubertooth')
     if mode not in valid_modes:
         return jsonify({'error': f'Invalid mode. Must be one of: {valid_modes}'}), 400
 
@@ -250,8 +250,8 @@ def start_scan():
             logger.debug(f"BT seen-before update failed: {e}")
 
     # Setup seen-before callback
-    if scanner._on_device_updated is None:
+    if _handle_seen_before not in scanner._on_device_updated_callbacks:
-        scanner._on_device_updated = _handle_seen_before
+        scanner.add_device_callback(_handle_seen_before)
 
     # Ensure cache is initialized
     with _bt_seen_lock:

routes/bt_locate.py

@@ -0,0 +1,284 @@
+"""
+BT Locate — Bluetooth SAR Device Location Flask Blueprint.
+
+Provides endpoints for managing locate sessions, streaming detection events,
+and retrieving GPS-tagged signal trails.
+"""
+
+from __future__ import annotations
+
+import logging
+from collections.abc import Generator
+
+from flask import Blueprint, Response, jsonify, request
+
+from utils.bluetooth.irk_extractor import get_paired_irks
+from utils.bt_locate import (
+    Environment,
+    LocateTarget,
+    get_locate_session,
+    resolve_rpa,
+    start_locate_session,
+    stop_locate_session,
+)
+from utils.sse import format_sse
+
+logger = logging.getLogger('intercept.bt_locate')
+
+bt_locate_bp = Blueprint('bt_locate', __name__, url_prefix='/bt_locate')
+
+
+@bt_locate_bp.route('/start', methods=['POST'])
+def start_session():
+    """
+    Start a locate session.
+
+    Request JSON:
+        - mac_address: Target MAC address (optional)
+        - name_pattern: Target name substring (optional)
+        - irk_hex: Identity Resolving Key hex string (optional)
+        - device_id: Device ID from Bluetooth scanner (optional)
+        - known_name: Hand-off device name (optional)
+        - known_manufacturer: Hand-off manufacturer (optional)
+        - last_known_rssi: Hand-off last RSSI (optional)
+        - environment: 'FREE_SPACE', 'OUTDOOR', 'INDOOR', 'CUSTOM' (default: OUTDOOR)
+        - custom_exponent: Path loss exponent for CUSTOM environment (optional)
+
+    Returns:
+        JSON with session status.
+    """
+    data = request.get_json() or {}
+
+    # Build target
+    target = LocateTarget(
+        mac_address=data.get('mac_address'),
+        name_pattern=data.get('name_pattern'),
+        irk_hex=data.get('irk_hex'),
+        device_id=data.get('device_id'),
+        known_name=data.get('known_name'),
+        known_manufacturer=data.get('known_manufacturer'),
+        last_known_rssi=data.get('last_known_rssi'),
+    )
+
+    # At least one identifier required
+    if not any([target.mac_address, target.name_pattern, target.irk_hex, target.device_id]):
+        return jsonify({'error': 'At least one target identifier required (mac_address, name_pattern, irk_hex, or device_id)'}), 400
+
+    # Parse environment
+    env_str = data.get('environment', 'OUTDOOR').upper()
+    try:
+        environment = Environment[env_str]
+    except KeyError:
+        return jsonify({'error': f'Invalid environment: {env_str}'}), 400
+
+    custom_exponent = data.get('custom_exponent')
+    if custom_exponent is not None:
+        try:
+            custom_exponent = float(custom_exponent)
+        except (ValueError, TypeError):
+            return jsonify({'error': 'custom_exponent must be a number'}), 400
+
+    # Fallback coordinates when GPS is unavailable (from user settings)
+    fallback_lat = None
+    fallback_lon = None
+    if data.get('fallback_lat') is not None and data.get('fallback_lon') is not None:
+        try:
+            fallback_lat = float(data['fallback_lat'])
+            fallback_lon = float(data['fallback_lon'])
+        except (ValueError, TypeError):
+            pass
+
+    logger.info(
+        f"Starting locate session: target={target.to_dict()}, "
+        f"env={environment.name}, fallback=({fallback_lat}, {fallback_lon})"
+    )
+
+    session = start_locate_session(
+        target, environment, custom_exponent, fallback_lat, fallback_lon
+    )
+
+    return jsonify({
+        'status': 'started',
+        'session': session.get_status(),
+    })
+
+
+@bt_locate_bp.route('/stop', methods=['POST'])
+def stop_session():
+    """Stop the active locate session."""
+    session = get_locate_session()
+    if not session:
+        return jsonify({'status': 'no_session'})
+
+    stop_locate_session()
+    return jsonify({'status': 'stopped'})
+
+
+@bt_locate_bp.route('/status', methods=['GET'])
+def get_status():
+    """Get locate session status."""
+    session = get_locate_session()
+    if not session:
+        return jsonify({
+            'active': False,
+            'target': None,
+        })
+
+    return jsonify(session.get_status())
+
+
+@bt_locate_bp.route('/trail', methods=['GET'])
+def get_trail():
+    """Get detection trail data."""
+    session = get_locate_session()
+    if not session:
+        return jsonify({'trail': [], 'gps_trail': []})
+
+    return jsonify({
+        'trail': session.get_trail(),
+        'gps_trail': session.get_gps_trail(),
+    })
+
+
+@bt_locate_bp.route('/stream', methods=['GET'])
+def stream_detections():
+    """SSE stream of detection events."""
+
+    def event_generator() -> Generator[str, None, None]:
+        while True:
+            # Re-fetch session each iteration in case it changes
+            s = get_locate_session()
+            if not s:
+                yield format_sse({'type': 'session_ended'}, event='session_ended')
+                return
+
+            try:
+                event = s.event_queue.get(timeout=2.0)
+                yield format_sse(event, event='detection')
+            except Exception:
+                yield format_sse({}, event='ping')
+
+    return Response(
+        event_generator(),
+        mimetype='text/event-stream',
+        headers={
+            'Cache-Control': 'no-cache',
+            'Connection': 'keep-alive',
+            'X-Accel-Buffering': 'no',
+        }
+    )
+
+
+@bt_locate_bp.route('/resolve_rpa', methods=['POST'])
+def test_resolve_rpa():
+    """
+    Test if an IRK resolves to a given address.
+
+    Request JSON:
+        - irk_hex: 16-byte IRK as hex string
+        - address: BLE address string
+
+    Returns:
+        JSON with resolution result.
+    """
+    data = request.get_json() or {}
+    irk_hex = data.get('irk_hex', '')
+    address = data.get('address', '')
+
+    if not irk_hex or not address:
+        return jsonify({'error': 'irk_hex and address are required'}), 400
+
+    try:
+        irk = bytes.fromhex(irk_hex)
+    except ValueError:
+        return jsonify({'error': 'Invalid IRK hex string'}), 400
+
+    if len(irk) != 16:
+        return jsonify({'error': 'IRK must be exactly 16 bytes (32 hex characters)'}), 400
+
+    result = resolve_rpa(irk, address)
+    return jsonify({
+        'resolved': result,
+        'irk_hex': irk_hex,
+        'address': address,
+    })
+
+
+@bt_locate_bp.route('/environment', methods=['POST'])
+def set_environment():
+    """Update the environment on the active session."""
+    session = get_locate_session()
+    if not session:
+        return jsonify({'error': 'no active session'}), 400
+
+    data = request.get_json() or {}
+    env_str = data.get('environment', '').upper()
+    try:
+        environment = Environment[env_str]
+    except KeyError:
+        return jsonify({'error': f'Invalid environment: {env_str}'}), 400
+
+    custom_exponent = data.get('custom_exponent')
+    if custom_exponent is not None:
+        try:
+            custom_exponent = float(custom_exponent)
+        except (ValueError, TypeError):
+            custom_exponent = None
+
+    session.set_environment(environment, custom_exponent)
+    return jsonify({
+        'status': 'updated',
+        'environment': environment.name,
+        'path_loss_exponent': session.estimator.n,
+    })
+
+
+@bt_locate_bp.route('/debug', methods=['GET'])
+def debug_matching():
+    """Debug endpoint showing scanner devices and match results."""
+    session = get_locate_session()
+    if not session:
+        return jsonify({'error': 'no session'})
+
+    scanner = session._scanner
+    if not scanner:
+        return jsonify({'error': 'no scanner'})
+
+    devices = scanner.get_devices(max_age_seconds=30)
+    return jsonify({
+        'target': session.target.to_dict(),
+        'device_count': len(devices),
+        'devices': [
+            {
+                'device_id': d.device_id,
+                'address': d.address,
+                'name': d.name,
+                'rssi': d.rssi_current,
+                'matches': session.target.matches(d),
+            }
+            for d in devices
+        ],
+    })
+
+
+@bt_locate_bp.route('/paired_irks', methods=['GET'])
+def paired_irks():
+    """Return paired Bluetooth devices that have IRKs."""
+    try:
+        devices = get_paired_irks()
+    except Exception as e:
+        logger.exception("Failed to read paired IRKs")
+        return jsonify({'devices': [], 'error': str(e)})
+
+    return jsonify({'devices': devices})
+
+
+@bt_locate_bp.route('/clear_trail', methods=['POST'])
+def clear_trail():
+    """Clear the detection trail."""
+    session = get_locate_session()
+    if not session:
+        return jsonify({'status': 'no_session'})
+
+    session.clear_trail()
+    return jsonify({'status': 'cleared'})

routes/gps.py

@@ -4,19 +4,24 @@ from __future__ import annotations
 
 import queue
 import time
-from typing import Generator
+from collections.abc import Generator
 
-from flask import Blueprint, jsonify, request, Response
+from flask import Blueprint, Response, jsonify
 
+from utils.gps import (
+    GPSPosition,
+    GPSSkyData,
+    detect_gps_devices,
+    get_current_position,
+    get_gps_reader,
+    is_gpsd_running,
+    start_gpsd,
+    start_gpsd_daemon,
+    stop_gps,
+    stop_gpsd_daemon,
+)
 from utils.logging import get_logger
 from utils.sse import format_sse
-from utils.gps import (
-    get_gps_reader,
-    start_gpsd,
-    stop_gps,
-    get_current_position,
-    GPSPosition,
-)
 
 logger = get_logger('intercept.gps')
 
@@ -29,12 +34,24 @@ _gps_queue: queue.Queue = queue.Queue(maxsize=100)
 def _position_callback(position: GPSPosition) -> None:
     """Callback to queue position updates for SSE stream."""
     try:
-        _gps_queue.put_nowait(position.to_dict())
+        _gps_queue.put_nowait({'type': 'position', **position.to_dict()})
     except queue.Full:
         # Discard oldest if queue is full
         try:
             _gps_queue.get_nowait()
-            _gps_queue.put_nowait(position.to_dict())
+            _gps_queue.put_nowait({'type': 'position', **position.to_dict()})
+        except queue.Empty:
+            pass
+
+
+def _sky_callback(sky: GPSSkyData) -> None:
+    """Callback to queue sky data updates for SSE stream."""
+    try:
+        _gps_queue.put_nowait({'type': 'sky', **sky.to_dict()})
+    except queue.Full:
+        try:
+            _gps_queue.get_nowait()
+            _gps_queue.put_nowait({'type': 'sky', **sky.to_dict()})
         except queue.Empty:
             pass
 
@@ -45,36 +62,44 @@ def auto_connect_gps():
     Automatically connect to gpsd if available.
 
     Called on page load to seamlessly enable GPS if gpsd is running.
+    If gpsd is not running, attempts to detect GPS devices and start gpsd.
     Returns current status if already connected.
     """
-    import socket
-
     # Check if already running
     reader = get_gps_reader()
     if reader and reader.is_running:
         position = reader.position
+        sky = reader.sky
         return jsonify({
             'status': 'connected',
             'source': 'gpsd',
             'has_fix': position is not None,
-            'position': position.to_dict() if position else None
+            'position': position.to_dict() if position else None,
+            'sky': sky.to_dict() if sky else None,
         })
 
-    # Try to connect to gpsd on localhost:2947
     host = 'localhost'
     port = 2947
 
-    # First check if gpsd is reachable
+    # If gpsd isn't running, try to detect a device and start it
-    try:
+    if not is_gpsd_running(host, port):
-        sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+        devices = detect_gps_devices()
-        sock.settimeout(1.0)
+        if not devices:
-        sock.connect((host, port))
+            return jsonify({
-        sock.close()
+                'status': 'unavailable',
-    except Exception:
+                'message': 'No GPS device detected'
-        return jsonify({
+            })
-            'status': 'unavailable',
+
-            'message': 'gpsd not running'
+        # Try to start gpsd with the first detected device
-        })
+        device_path = devices[0]['path']
+        success, msg = start_gpsd_daemon(device_path, host, port)
+        if not success:
+            return jsonify({
+                'status': 'unavailable',
+                'message': msg,
+                'devices': devices,
+            })
+        logger.info(f"Auto-started gpsd on {device_path}")
 
     # Clear the queue
     while not _gps_queue.empty():
@@ -84,14 +109,17 @@ def auto_connect_gps():
             break
 
     # Start the gpsd client
-    success = start_gpsd(host, port, callback=_position_callback)
+    success = start_gpsd(host, port,
+                         callback=_position_callback,
+                         sky_callback=_sky_callback)
 
     if success:
         return jsonify({
             'status': 'connected',
             'source': 'gpsd',
             'has_fix': False,
-            'position': None
+            'position': None,
+            'sky': None,
         })
     else:
         return jsonify({
@@ -100,14 +128,26 @@ def auto_connect_gps():
         })
 
 
+@gps_bp.route('/devices')
+def list_gps_devices():
+    """List detected GPS serial devices."""
+    devices = detect_gps_devices()
+    return jsonify({
+        'devices': devices,
+        'gpsd_running': is_gpsd_running(),
+    })
+
+
 @gps_bp.route('/stop', methods=['POST'])
 def stop_gps_reader():
-    """Stop GPS client."""
+    """Stop GPS client and gpsd daemon if we started it."""
     reader = get_gps_reader()
     if reader:
         reader.remove_callback(_position_callback)
+        reader.remove_sky_callback(_sky_callback)
 
     stop_gps()
+    stop_gpsd_daemon()
 
     return jsonify({'status': 'stopped'})
 
@@ -122,15 +162,18 @@ def get_gps_status():
             'running': False,
             'device': None,
             'position': None,
+            'sky': None,
             'error': None,
             'message': 'GPS client not started'
         })
 
     position = reader.position
+    sky = reader.sky
     return jsonify({
         'running': reader.is_running,
         'device': reader.device_path,
         'position': position.to_dict() if position else None,
+        'sky': sky.to_dict() if sky else None,
         'last_update': reader.last_update.isoformat() if reader.last_update else None,
         'error': reader.error,
         'message': 'Waiting for GPS fix - ensure GPS has clear view of sky' if reader.is_running and not position else None
@@ -161,18 +204,42 @@ def get_position():
             })
 
 
+@gps_bp.route('/satellites')
+def get_satellites():
+    """Get current satellite sky view data."""
+    reader = get_gps_reader()
+
+    if not reader or not reader.is_running:
+        return jsonify({
+            'status': 'error',
+            'message': 'GPS client not running'
+        }), 400
+
+    sky = reader.sky
+    if sky:
+        return jsonify({
+            'status': 'ok',
+            'sky': sky.to_dict()
+        })
+    else:
+        return jsonify({
+            'status': 'waiting',
+            'message': 'Waiting for satellite data'
+        })
+
+
 @gps_bp.route('/stream')
 def stream_gps():
-    """SSE stream of GPS position updates."""
+    """SSE stream of GPS position and sky updates."""
     def generate() -> Generator[str, None, None]:
         last_keepalive = time.time()
         keepalive_interval = 30.0
 
         while True:
             try:
-                position = _gps_queue.get(timeout=1)
+                data = _gps_queue.get(timeout=1)
                 last_keepalive = time.time()
-                yield format_sse({'type': 'position', **position})
+                yield format_sse(data)
             except queue.Empty:
                 now = time.time()
                 if now - last_keepalive >= keepalive_interval:

routes/satellite.py

@@ -16,6 +16,13 @@ from flask import Blueprint, jsonify, request, render_template, Response
 from config import SHARED_OBSERVER_LOCATION_ENABLED
 
 from data.satellites import TLE_SATELLITES
+from utils.database import (
+    get_tracked_satellites,
+    add_tracked_satellite,
+    bulk_add_tracked_satellites,
+    update_tracked_satellite,
+    remove_tracked_satellite,
+)
 from utils.logging import satellite_logger as logger
 from utils.validation import validate_latitude, validate_longitude, validate_hours, validate_elevation
 
@@ -31,12 +38,32 @@ ALLOWED_TLE_HOSTS = ['celestrak.org', 'celestrak.com', 'www.celestrak.org', 'www
 _tle_cache = dict(TLE_SATELLITES)
 
 
+def _load_db_satellites_into_cache():
+    """Load user-tracked satellites from DB into the TLE cache."""
+    global _tle_cache
+    try:
+        db_sats = get_tracked_satellites()
+        loaded = 0
+        for sat in db_sats:
+            if sat['tle_line1'] and sat['tle_line2']:
+                # Use a cache key derived from name (sanitised)
+                cache_key = sat['name'].replace(' ', '-').upper()
+                if cache_key not in _tle_cache:
+                    _tle_cache[cache_key] = (sat['name'], sat['tle_line1'], sat['tle_line2'])
+                    loaded += 1
+        if loaded:
+            logger.info(f"Loaded {loaded} user-tracked satellites into TLE cache")
+    except Exception as e:
+        logger.warning(f"Failed to load DB satellites into TLE cache: {e}")
+
+
 def init_tle_auto_refresh():
     """Initialize TLE auto-refresh. Called by app.py after initialization."""
     import threading
 
     def _auto_refresh_tle():
         try:
+            _load_db_satellites_into_cache()
             updated = refresh_tle_data()
             if updated:
                 logger.info(f"Auto-refreshed TLE data for: {', '.join(updated)}")
@@ -543,3 +570,75 @@ def fetch_celestrak(category):
     except Exception as e:
         logger.error(f"Error fetching CelesTrak data: {e}")
         return jsonify({'status': 'error', 'message': 'Failed to fetch satellite data'})
+
+
+# =============================================================================
+# Tracked Satellites CRUD
+# =============================================================================
+
+@satellite_bp.route('/tracked', methods=['GET'])
+def list_tracked_satellites():
+    """Return all tracked satellites from the database."""
+    enabled_only = request.args.get('enabled', '').lower() == 'true'
+    sats = get_tracked_satellites(enabled_only=enabled_only)
+    return jsonify({'status': 'success', 'satellites': sats})
+
+
+@satellite_bp.route('/tracked', methods=['POST'])
+def add_tracked_satellites_endpoint():
+    """Add one or more tracked satellites."""
+    global _tle_cache
+    data = request.json
+    if not data:
+        return jsonify({'status': 'error', 'message': 'No data provided'}), 400
+
+    # Accept a single satellite dict or a list
+    sat_list = data if isinstance(data, list) else [data]
+
+    added = 0
+    for sat in sat_list:
+        norad_id = str(sat.get('norad_id', sat.get('norad', '')))
+        name = sat.get('name', '')
+        if not norad_id or not name:
+            continue
+        tle1 = sat.get('tle_line1', sat.get('tle1'))
+        tle2 = sat.get('tle_line2', sat.get('tle2'))
+        enabled = sat.get('enabled', True)
+
+        if add_tracked_satellite(norad_id, name, tle1, tle2, enabled):
+            added += 1
+
+        # Also inject into TLE cache if we have TLE data
+        if tle1 and tle2:
+            cache_key = name.replace(' ', '-').upper()
+            _tle_cache[cache_key] = (name, tle1, tle2)
+
+    return jsonify({
+        'status': 'success',
+        'added': added,
+        'satellites': get_tracked_satellites(),
+    })
+
+
+@satellite_bp.route('/tracked/<norad_id>', methods=['PUT'])
+def update_tracked_satellite_endpoint(norad_id):
+    """Update the enabled state of a tracked satellite."""
+    data = request.json or {}
+    enabled = data.get('enabled')
+    if enabled is None:
+        return jsonify({'status': 'error', 'message': 'Missing enabled field'}), 400
+
+    ok = update_tracked_satellite(str(norad_id), bool(enabled))
+    if ok:
+        return jsonify({'status': 'success'})
+    return jsonify({'status': 'error', 'message': 'Satellite not found'}), 404
+
+
+@satellite_bp.route('/tracked/<norad_id>', methods=['DELETE'])
+def delete_tracked_satellite_endpoint(norad_id):
+    """Remove a tracked satellite by NORAD ID."""
+    ok, msg = remove_tracked_satellite(str(norad_id))
+    if ok:
+        return jsonify({'status': 'success', 'message': msg})
+    status_code = 403 if 'builtin' in msg.lower() else 404
+    return jsonify({'status': 'error', 'message': msg}), status_code

routes/sensor.py

@@ -199,10 +199,16 @@ def start_sensor() -> Response:
             thread.start()
 
             # Monitor stderr
+            # Filter noisy rtl_433 diagnostics that aren't useful to display
+            _stderr_noise = (
+                'bitbuffer_add_bit',
+                'row count limit',
+            )
+
             def monitor_stderr():
                 for line in app_module.sensor_process.stderr:
                     err = line.decode('utf-8', errors='replace').strip()
-                    if err:
+                    if err and not any(noise in err for noise in _stderr_noise):
                         logger.debug(f"[rtl_433] {err}")
                         app_module.sensor_queue.put({'type': 'info', 'text': f'[rtl_433] {err}'})
 

setup.sh

@@ -137,6 +137,14 @@ need_sudo() {
   fi
 }
 
+# Refresh sudo credential cache so long-running builds don't trigger
+# mid-compilation password prompts (which can fail due to TTY issues
+# inside subshells). Safe to call multiple times.
+refresh_sudo() {
+  [[ -z "${SUDO:-}" ]] && return 0
+  sudo -v 2>/dev/null || true
+}
+
 detect_os() {
   if [[ "${OSTYPE:-}" == "darwin"* ]]; then
     OS="macos"
@@ -388,7 +396,7 @@ install_rtlamr_from_source() {
         if [[ -w /usr/local/bin ]]; then
           ln -sf "$GOPATH/bin/rtlamr" /usr/local/bin/rtlamr
         else
-          sudo ln -sf "$GOPATH/bin/rtlamr" /usr/local/bin/rtlamr
+          $SUDO ln -sf "$GOPATH/bin/rtlamr" /usr/local/bin/rtlamr
         fi
       else
         $SUDO ln -sf "$GOPATH/bin/rtlamr" /usr/local/bin/rtlamr
@@ -430,7 +438,8 @@ install_multimon_ng_from_source_macos() {
     if [[ -w /usr/local/bin ]]; then
       install -m 0755 multimon-ng /usr/local/bin/multimon-ng
     else
-      sudo install -m 0755 multimon-ng /usr/local/bin/multimon-ng
+      refresh_sudo
+      $SUDO install -m 0755 multimon-ng /usr/local/bin/multimon-ng
     fi
     ok "multimon-ng installed successfully from source"
   )
@@ -471,7 +480,8 @@ install_dsd_from_source() {
         if [[ -w /usr/local/lib ]]; then
           make install >/dev/null 2>&1
         else
-          sudo make install >/dev/null 2>&1
+          refresh_sudo
+          $SUDO make install >/dev/null 2>&1
         fi
       else
         $SUDO make install >/dev/null 2>&1
@@ -507,7 +517,8 @@ install_dsd_from_source() {
         if [[ -w /usr/local/bin ]]; then
           install -m 0755 dsd-fme /usr/local/bin/dsd 2>/dev/null || install -m 0755 dsd /usr/local/bin/dsd 2>/dev/null || true
         else
-          sudo install -m 0755 dsd-fme /usr/local/bin/dsd 2>/dev/null || sudo install -m 0755 dsd /usr/local/bin/dsd 2>/dev/null || true
+          refresh_sudo
+          $SUDO install -m 0755 dsd-fme /usr/local/bin/dsd 2>/dev/null || $SUDO install -m 0755 dsd /usr/local/bin/dsd 2>/dev/null || true
         fi
       else
         $SUDO make install >/dev/null 2>&1 \
@@ -545,7 +556,8 @@ install_dump1090_from_source_macos() {
       if [[ -w /usr/local/bin ]]; then
         install -m 0755 dump1090 /usr/local/bin/dump1090
       else
-        sudo install -m 0755 dump1090 /usr/local/bin/dump1090
+        refresh_sudo
+        $SUDO install -m 0755 dump1090 /usr/local/bin/dump1090
       fi
       ok "dump1090 installed successfully from source"
     else
@@ -571,18 +583,54 @@ install_acarsdec_from_source_macos() {
       || { warn "Failed to clone acarsdec"; exit 1; }
 
     cd "$tmp_dir/acarsdec"
+
+    # Fix compiler flags for macOS Apple Silicon (ARM64)
+    # -march=native can fail with Apple Clang on M-series chips
+    # -Ofast is deprecated in modern Clang
+    if [[ "$(uname -m)" == "arm64" ]]; then
+      sed -i '' 's/-Ofast -march=native/-O3 -ffast-math/g' CMakeLists.txt
+      info "Patched compiler flags for Apple Silicon (arm64)"
+    fi
+
+    # Fix pthread_tryjoin_np (Linux-only GNU extension) for macOS
+    # Replace with pthread_join which provides equivalent behavior
+    if grep -q 'pthread_tryjoin_np' rtl.c 2>/dev/null; then
+      sed -i '' 's/pthread_tryjoin_np(\([^,]*\), NULL)/pthread_join(\1, NULL)/g' rtl.c
+      info "Patched pthread_tryjoin_np for macOS compatibility"
+    fi
+
+    # Fix libacars linking on macOS (upstream issue #112)
+    # Use LIBACARS_LINK_LIBRARIES (full path) instead of LIBACARS_LIBRARIES (name only)
+    if grep -q 'LIBACARS_LIBRARIES' CMakeLists.txt 2>/dev/null; then
+      sed -i '' 's/${LIBACARS_LIBRARIES}/${LIBACARS_LINK_LIBRARIES}/g' CMakeLists.txt
+      info "Patched libacars linking for macOS"
+    fi
+
     mkdir -p build && cd build
 
+    # Set Homebrew paths for Apple Silicon (/opt/homebrew) or Intel (/usr/local)
+    HOMEBREW_PREFIX="$(brew --prefix)"
+    export PKG_CONFIG_PATH="${HOMEBREW_PREFIX}/lib/pkgconfig:${PKG_CONFIG_PATH:-}"
+    export CMAKE_PREFIX_PATH="${HOMEBREW_PREFIX}"
+
     info "Compiling acarsdec..."
-    if cmake .. -Drtl=ON >/dev/null 2>&1 && make >/dev/null 2>&1; then
+    build_log="$tmp_dir/acarsdec-build.log"
+    if cmake .. -Drtl=ON \
+         -DCMAKE_C_FLAGS="-I${HOMEBREW_PREFIX}/include" \
+         -DCMAKE_EXE_LINKER_FLAGS="-L${HOMEBREW_PREFIX}/lib" \
+         >"$build_log" 2>&1 \
+       && make >>"$build_log" 2>&1; then
       if [[ -w /usr/local/bin ]]; then
         install -m 0755 acarsdec /usr/local/bin/acarsdec
       else
-        sudo install -m 0755 acarsdec /usr/local/bin/acarsdec
+        refresh_sudo
+        $SUDO install -m 0755 acarsdec /usr/local/bin/acarsdec
       fi
       ok "acarsdec installed successfully from source"
     else
       warn "Failed to build acarsdec. ACARS decoding will not be available."
+      warn "Build log (last 30 lines):"
+      tail -30 "$build_log" | while IFS= read -r line; do warn "  $line"; done
     fi
   )
 }
@@ -611,7 +659,8 @@ install_aiscatcher_from_source_macos() {
       if [[ -w /usr/local/bin ]]; then
         install -m 0755 AIS-catcher /usr/local/bin/AIS-catcher
       else
-        sudo install -m 0755 AIS-catcher /usr/local/bin/AIS-catcher
+        refresh_sudo
+        $SUDO install -m 0755 AIS-catcher /usr/local/bin/AIS-catcher
       fi
       ok "AIS-catcher installed successfully from source"
     else
@@ -640,9 +689,24 @@ install_satdump_from_source_debian() {
     cd "$tmp_dir/SatDump"
     mkdir -p build && cd build
 
-    info "Compiling SatDump (this may take a while)..."
+    info "Compiling SatDump (this is a large C++ project and may take 10-30 minutes)..."
-    if cmake -DCMAKE_BUILD_TYPE=Release -DBUILD_GUI=OFF -DCMAKE_INSTALL_LIBDIR=lib .. >/dev/null 2>&1 \
+    build_log="$tmp_dir/satdump-build.log"
-        && make -j "$(nproc)" >/dev/null 2>&1; then
+
+    # Show periodic progress while building so the user knows it's not hung
+    (
+      while true; do
+        sleep 30
+        if [ -f "$build_log" ]; then
+          local_lines=$(wc -l < "$build_log" 2>/dev/null || echo 0)
+          printf "  [*] Still compiling SatDump... (%s lines of build output so far)\n" "$local_lines"
+        fi
+      done
+    ) &
+    progress_pid=$!
+
+    if cmake -DCMAKE_BUILD_TYPE=Release -DBUILD_GUI=OFF -DCMAKE_INSTALL_LIBDIR=lib .. >"$build_log" 2>&1 \
+        && make -j "$(nproc)" >>"$build_log" 2>&1; then
+      kill $progress_pid 2>/dev/null; wait $progress_pid 2>/dev/null
       $SUDO make install >/dev/null 2>&1
       $SUDO ldconfig
 
@@ -659,7 +723,10 @@ install_satdump_from_source_debian() {
 
       ok "SatDump installed successfully."
     else
+      kill $progress_pid 2>/dev/null; wait $progress_pid 2>/dev/null
       warn "Failed to build SatDump from source. Weather satellite decoding will not be available."
+      warn "Build log (last 30 lines):"
+      tail -30 "$build_log" | while IFS= read -r line; do warn "  $line"; done
     fi
   )
 }
@@ -690,22 +757,49 @@ install_satdump_from_source_macos() {
     cd "$tmp_dir/SatDump"
     mkdir -p build && cd build
 
-    info "Compiling SatDump (this may take a while)..."
+    info "Compiling SatDump (this is a large C++ project and may take 10-30 minutes)..."
-    if cmake -DCMAKE_BUILD_TYPE=Release -DBUILD_GUI=OFF .. >/dev/null 2>&1 \
+    build_log="$tmp_dir/satdump-build.log"
-        && make -j "$(sysctl -n hw.ncpu)" >/dev/null 2>&1; then
+
+    # Show periodic progress while building so the user knows it's not hung
+    (
+      while true; do
+        sleep 30
+        if [ -f "$build_log" ]; then
+          local_lines=$(wc -l < "$build_log" 2>/dev/null || echo 0)
+          printf "  [*] Still compiling SatDump... (%s lines of build output so far)\n" "$local_lines"
+        fi
+      done
+    ) &
+    progress_pid=$!
+
+    if cmake -DCMAKE_BUILD_TYPE=Release -DBUILD_GUI=OFF .. >"$build_log" 2>&1 \
+        && make -j "$(sysctl -n hw.ncpu)" >>"$build_log" 2>&1; then
+      kill $progress_pid 2>/dev/null; wait $progress_pid 2>/dev/null
       if [[ -w /usr/local/bin ]]; then
         make install >/dev/null 2>&1
       else
-        sudo make install >/dev/null 2>&1
+        refresh_sudo
+        $SUDO make install >/dev/null 2>&1
       fi
       ok "SatDump installed successfully."
     else
+      kill $progress_pid 2>/dev/null; wait $progress_pid 2>/dev/null
       warn "Failed to build SatDump from source. Weather satellite decoding will not be available."
+      warn "Build log (last 30 lines):"
+      tail -30 "$build_log" | while IFS= read -r line; do warn "  $line"; done
     fi
   )
 }
 
 install_macos_packages() {
+  need_sudo
+
+  # Prime sudo credentials upfront so builds don't prompt mid-compilation
+  if [[ -n "${SUDO:-}" ]]; then
+    info "Some tools require sudo to install. You may be prompted for your password."
+    sudo -v || { fail "sudo authentication failed"; exit 1; }
+  fi
+
   TOTAL_STEPS=19
   CURRENT_STEP=0
 

static/css/index.css

@@ -4119,7 +4119,7 @@ header h1 .tagline {
     border: 1px solid var(--border-color);
     border-radius: 6px;
     flex-shrink: 0;
-    height: 140px;
+    max-height: 340px;
     overflow: hidden;
 }
 
@@ -4140,7 +4140,9 @@ header h1 .tagline {
 
 .bt-detail-body {
     padding: 8px 10px;
-    height: calc(100% - 30px);
+    height: auto;
+    max-height: calc(100% - 30px);
+    overflow-y: auto;
 }
 
 .bt-detail-placeholder {
@@ -4319,6 +4321,110 @@ header h1 .tagline {
     color: #9fffd1;
 }
 
+/* Service Data Inspector */
+.bt-detail-service-inspector {
+    margin-bottom: 6px;
+}
+
+.bt-inspector-toggle {
+    font-size: 10px;
+    color: var(--accent-cyan);
+    cursor: pointer;
+    padding: 3px 0;
+    user-select: none;
+}
+
+.bt-inspector-toggle:hover {
+    color: #fff;
+}
+
+.bt-inspector-arrow {
+    display: inline-block;
+    transition: transform 0.2s;
+    font-size: 9px;
+}
+
+.bt-inspector-arrow.open {
+    transform: rotate(90deg);
+}
+
+.bt-inspector-content {
+    background: var(--bg-secondary);
+    border-radius: 3px;
+    padding: 6px 8px;
+    margin-top: 4px;
+    font-family: var(--font-mono);
+    font-size: 9px;
+    color: var(--text-dim);
+    max-height: 100px;
+    overflow-y: auto;
+    word-break: break-all;
+}
+
+.bt-inspector-row {
+    display: flex;
+    justify-content: space-between;
+    gap: 8px;
+    padding: 2px 0;
+    border-bottom: 1px solid rgba(255,255,255,0.04);
+}
+
+.bt-inspector-row:last-child {
+    border-bottom: none;
+}
+
+.bt-inspector-label {
+    color: var(--text-dim);
+    flex-shrink: 0;
+}
+
+.bt-inspector-value {
+    color: var(--text-primary);
+    text-align: right;
+    min-width: 0;
+    overflow: hidden;
+    text-overflow: ellipsis;
+}
+
+/* MAC Cluster Badge */
+.bt-mac-cluster-badge {
+    display: inline-block;
+    background: rgba(245, 158, 11, 0.2);
+    color: #f59e0b;
+    font-size: 8px;
+    font-weight: 600;
+    padding: 1px 4px;
+    border-radius: 3px;
+    margin-left: 6px;
+    vertical-align: middle;
+}
+
+/* Behavioral Flag Badges */
+.bt-flag-badge {
+    display: inline-block;
+    font-size: 8px;
+    font-weight: 600;
+    padding: 1px 4px;
+    border-radius: 3px;
+    margin-left: 3px;
+    vertical-align: middle;
+}
+
+.bt-flag-badge.persistent {
+    background: rgba(245, 158, 11, 0.15);
+    color: #f59e0b;
+}
+
+.bt-flag-badge.beacon-like {
+    background: rgba(59, 130, 246, 0.15);
+    color: #3b82f6;
+}
+
+.bt-flag-badge.strong-stable {
+    background: rgba(34, 197, 94, 0.15);
+    color: #22c55e;
+}
+
 /* Selected device highlight */
 .bt-device-row.selected {
     background: rgba(0, 212, 255, 0.1);
@@ -4469,14 +4575,15 @@ header h1 .tagline {
 .bt-row-main {
     display: flex;
     justify-content: space-between;
-    align-items: center;
+    align-items: flex-start;
     gap: 12px;
 }
 
 .bt-row-left {
     display: flex;
-    align-items: center;
+    align-items: baseline;
-    gap: 8px;
+    flex-wrap: wrap;
+    gap: 4px 8px;
     min-width: 0;
     flex: 1;
 }
@@ -4521,13 +4628,25 @@ header h1 .tagline {
     color: #22c55e;
 }
 
+.bt-irk-badge {
+    display: inline-block;
+    padding: 1px 4px;
+    border-radius: 3px;
+    font-size: 9px;
+    font-weight: 600;
+    letter-spacing: 0.3px;
+    background: rgba(168, 85, 247, 0.15);
+    color: #a855f7;
+    border: 1px solid rgba(168, 85, 247, 0.3);
+}
+
 .bt-device-name {
     font-size: 13px;
     font-weight: 600;
     color: var(--text-primary);
-    white-space: nowrap;
+    overflow-wrap: break-word;
-    overflow: hidden;
+    word-break: break-word;
-    text-overflow: ellipsis;
+    min-width: 0;
 }
 
 .bt-rssi-container {
@@ -4584,6 +4703,12 @@ header h1 .tagline {
     text-overflow: ellipsis;
 }
 
+.bt-row-actions {
+    display: flex;
+    justify-content: flex-end;
+    padding: 4px 4px 0 42px;
+}
+
 /* Bluetooth Device Modal */
 .bt-modal-overlay {
     position: fixed;

static/css/modes/bt_locate.css

@@ -0,0 +1,430 @@
+/* BT Locate Mode Styles */
+
+/* Environment preset grid */
+.btl-env-grid {
+    display: grid;
+    grid-template-columns: 1fr 1fr 1fr;
+    gap: 6px;
+}
+
+.btl-env-btn {
+    display: flex;
+    flex-direction: column;
+    align-items: center;
+    gap: 2px;
+    padding: 8px 4px;
+    background: rgba(255, 255, 255, 0.03);
+    border: 1px solid rgba(255, 255, 255, 0.1);
+    border-radius: 6px;
+    cursor: pointer;
+    transition: all 0.2s;
+    color: var(--text-secondary);
+}
+
+.btl-env-btn:hover {
+    background: rgba(255, 255, 255, 0.06);
+    border-color: rgba(255, 255, 255, 0.2);
+}
+
+.btl-env-btn.active {
+    background: rgba(0, 255, 136, 0.1);
+    border-color: var(--accent-green, #00ff88);
+    color: var(--text-primary);
+}
+
+.btl-env-icon {
+    font-size: 18px;
+    line-height: 1;
+}
+
+.btl-env-label {
+    font-size: 10px;
+    font-weight: 600;
+    text-transform: uppercase;
+}
+
+.btl-env-n {
+    font-size: 9px;
+    font-family: var(--font-mono);
+    color: var(--text-dim);
+}
+
+/* ============================================
+   PROXIMITY HUD — main visuals area
+   ============================================ */
+
+.btl-hud {
+    display: flex;
+    flex-direction: column;
+    gap: 0;
+    background: rgba(0, 0, 0, 0.5);
+    border: 1px solid rgba(255, 255, 255, 0.08);
+    border-radius: 8px;
+    flex-shrink: 0;
+    overflow: hidden;
+}
+
+.btl-hud-top {
+    display: flex;
+    align-items: center;
+    gap: 20px;
+    padding: 14px 20px;
+}
+
+.btl-hud-band {
+    font-size: 22px;
+    font-weight: 800;
+    font-family: var(--font-mono);
+    letter-spacing: 2px;
+    padding: 14px 20px;
+    border-radius: 8px;
+    background: rgba(255, 255, 255, 0.03);
+    border: 2px solid rgba(255, 255, 255, 0.1);
+    color: var(--text-dim);
+    text-align: center;
+    min-width: 130px;
+    transition: all 0.3s;
+    flex-shrink: 0;
+}
+
+.btl-hud-band.immediate {
+    color: #ef4444;
+    border-color: #ef4444;
+    background: rgba(239, 68, 68, 0.15);
+    box-shadow: 0 0 20px rgba(239, 68, 68, 0.2);
+    animation: btl-pulse 1s ease-in-out infinite;
+}
+
+.btl-hud-band.near {
+    color: #f97316;
+    border-color: #f97316;
+    background: rgba(249, 115, 22, 0.12);
+    box-shadow: 0 0 15px rgba(249, 115, 22, 0.15);
+    animation: btl-pulse 2s ease-in-out infinite;
+}
+
+.btl-hud-band.far {
+    color: #eab308;
+    border-color: #eab308;
+    background: rgba(234, 179, 8, 0.1);
+    box-shadow: 0 0 10px rgba(234, 179, 8, 0.1);
+}
+
+@keyframes btl-pulse {
+    0%, 100% { opacity: 1; }
+    50% { opacity: 0.6; }
+}
+
+.btl-hud-metrics {
+    display: flex;
+    gap: 20px;
+    flex: 1;
+    align-items: flex-start;
+}
+
+.btl-hud-separator {
+    width: 1px;
+    height: 40px;
+    background: rgba(255, 255, 255, 0.08);
+    align-self: center;
+    flex-shrink: 0;
+}
+
+.btl-hud-metric {
+    display: flex;
+    flex-direction: column;
+    align-items: center;
+    min-width: 60px;
+}
+
+.btl-hud-metric-lg .btl-hud-value {
+    font-size: 28px;
+}
+
+.btl-hud-value {
+    font-size: 22px;
+    font-weight: 700;
+    font-family: var(--font-mono);
+    color: var(--text-primary);
+    line-height: 1.1;
+}
+
+.btl-hud-unit {
+    font-size: 10px;
+    color: var(--text-dim);
+    font-family: var(--font-mono);
+}
+
+.btl-hud-label {
+    font-size: 9px;
+    color: var(--text-dim);
+    text-transform: uppercase;
+    letter-spacing: 0.5px;
+    margin-top: 2px;
+}
+
+.btl-hud-controls {
+    display: flex;
+    flex-direction: column;
+    gap: 6px;
+    flex-shrink: 0;
+}
+
+.btl-hud-audio-toggle {
+    display: flex;
+    align-items: center;
+    gap: 5px;
+    font-size: 11px;
+    color: var(--text-secondary);
+    cursor: pointer;
+    white-space: nowrap;
+}
+
+.btl-hud-audio-toggle input[type="checkbox"] {
+    margin: 0;
+}
+
+.btl-hud-clear-btn {
+    padding: 4px 10px;
+    font-size: 10px;
+    background: rgba(255, 255, 255, 0.05);
+    border: 1px solid rgba(255, 255, 255, 0.1);
+    border-radius: 4px;
+    color: var(--text-dim);
+    cursor: pointer;
+    transition: all 0.2s;
+}
+
+.btl-hud-clear-btn:hover {
+    background: rgba(255, 255, 255, 0.1);
+    color: var(--text-secondary);
+}
+
+/* Bottom info bar */
+.btl-hud-bottom {
+    display: flex;
+    justify-content: space-between;
+    align-items: center;
+    padding: 6px 20px;
+    background: rgba(0, 0, 0, 0.3);
+    border-top: 1px solid rgba(255, 255, 255, 0.05);
+}
+
+.btl-hud-info {
+    display: flex;
+    align-items: center;
+    gap: 6px;
+    flex-wrap: wrap;
+}
+
+.btl-hud-info-item {
+    font-size: 10px;
+    font-family: var(--font-mono);
+    color: var(--text-dim);
+}
+
+.btl-hud-info-sep {
+    color: rgba(255, 255, 255, 0.15);
+    font-size: 10px;
+}
+
+.btl-hud-diag {
+    display: none;
+    font-size: 9px;
+    color: var(--text-dim);
+    font-family: var(--font-mono);
+    opacity: 0.5;
+    white-space: nowrap;
+}
+
+.btl-hud-diag:not(:empty) {
+    display: block;
+}
+
+/* ============================================
+   VISUALS AREA — map + chart
+   ============================================ */
+
+.btl-visuals-container {
+    display: flex;
+    flex-direction: column;
+    gap: 8px;
+    height: 100%;
+    padding: 8px;
+}
+
+.btl-map-container {
+    flex: 1;
+    min-height: 250px;
+    border-radius: 8px;
+    overflow: hidden;
+    border: 1px solid rgba(255, 255, 255, 0.1);
+}
+
+#btLocateMap {
+    width: 100%;
+    height: 100%;
+    background: #1a1a2e;
+}
+
+.btl-rssi-chart-container {
+    height: 100px;
+    background: rgba(0, 0, 0, 0.3);
+    border-radius: 8px;
+    border: 1px solid rgba(255, 255, 255, 0.1);
+    padding: 8px;
+    position: relative;
+    flex-shrink: 0;
+}
+
+.btl-rssi-chart-container .btl-chart-label {
+    position: absolute;
+    top: 4px;
+    left: 8px;
+    font-size: 9px;
+    color: var(--text-dim);
+    text-transform: uppercase;
+    letter-spacing: 1px;
+}
+
+#btLocateRssiChart {
+    width: 100%;
+    height: 100%;
+}
+
+/* ============================================
+   LOCATE BUTTON — Bluetooth device cards
+   ============================================ */
+
+.bt-locate-btn {
+    display: inline-flex;
+    align-items: center;
+    gap: 4px;
+    padding: 3px 8px;
+    font-size: 10px;
+    font-weight: 600;
+    text-transform: uppercase;
+    letter-spacing: 0.5px;
+    color: var(--accent-green, #00ff88);
+    background: rgba(0, 255, 136, 0.1);
+    border: 1px solid rgba(0, 255, 136, 0.3);
+    border-radius: 3px;
+    cursor: pointer;
+    transition: all 0.2s;
+}
+
+.bt-locate-btn:hover {
+    background: rgba(0, 255, 136, 0.2);
+    border-color: var(--accent-green, #00ff88);
+}
+
+.bt-locate-btn svg {
+    width: 10px;
+    height: 10px;
+}
+
+/* ============================================
+   IRK DETECT BUTTON + DEVICE PICKER
+   ============================================ */
+
+.btl-detect-irk-btn {
+    padding: 5px 10px;
+    font-size: 10px;
+    font-weight: 600;
+    text-transform: uppercase;
+    letter-spacing: 0.5px;
+    color: var(--accent-cyan, #00d4ff);
+    background: rgba(0, 212, 255, 0.1);
+    border: 1px solid rgba(0, 212, 255, 0.3);
+    border-radius: 4px;
+    cursor: pointer;
+    transition: all 0.2s;
+    white-space: nowrap;
+    flex-shrink: 0;
+}
+
+.btl-detect-irk-btn:hover {
+    background: rgba(0, 212, 255, 0.2);
+    border-color: var(--accent-cyan, #00d4ff);
+}
+
+.btl-detect-irk-btn:disabled {
+    opacity: 0.5;
+    cursor: wait;
+}
+
+.btl-irk-picker {
+    margin-top: 6px;
+    background: rgba(0, 0, 0, 0.3);
+    border: 1px solid rgba(255, 255, 255, 0.1);
+    border-radius: 6px;
+    overflow: hidden;
+}
+
+.btl-irk-picker-status {
+    padding: 8px 10px;
+    font-size: 10px;
+    color: var(--text-dim);
+    text-align: center;
+}
+
+.btl-irk-picker-list {
+    max-height: 160px;
+    overflow-y: auto;
+}
+
+.btl-irk-picker-item {
+    padding: 7px 10px;
+    cursor: pointer;
+    transition: background 0.15s;
+    border-top: 1px solid rgba(255, 255, 255, 0.05);
+}
+
+.btl-irk-picker-item:first-child {
+    border-top: none;
+}
+
+.btl-irk-picker-item:hover {
+    background: rgba(0, 255, 136, 0.08);
+}
+
+.btl-irk-picker-name {
+    font-size: 11px;
+    font-weight: 600;
+    color: var(--text-primary);
+}
+
+.btl-irk-picker-meta {
+    font-size: 9px;
+    font-family: var(--font-mono);
+    color: var(--text-dim);
+    margin-top: 1px;
+}
+
+/* ============================================
+   RESPONSIVE — stack HUD vertically on narrow
+   ============================================ */
+
+@media (max-width: 900px) {
+    .btl-hud {
+        flex-wrap: wrap;
+        gap: 10px;
+    }
+
+    .btl-hud-band {
+        min-width: unset;
+        width: 100%;
+        font-size: 20px;
+    }
+
+    .btl-hud-metrics {
+        width: 100%;
+        justify-content: space-around;
+    }
+
+    .btl-hud-controls {
+        flex-direction: row;
+        width: 100%;
+        justify-content: center;
+    }
+}

static/css/modes/gps.css

@@ -0,0 +1,337 @@
+/* GPS Mode Styles */
+
+/* Sidebar info grid */
+.gps-info-grid {
+    display: grid;
+    grid-template-columns: 1fr 1fr;
+    gap: 6px;
+}
+
+.gps-info-item {
+    display: flex;
+    flex-direction: column;
+    gap: 2px;
+    padding: 4px 6px;
+    background: var(--bg-primary);
+    border: 1px solid var(--border-color);
+    border-radius: 3px;
+}
+
+.gps-info-label {
+    font-size: 9px;
+    color: var(--text-dim);
+    text-transform: uppercase;
+    letter-spacing: 0.5px;
+}
+
+.gps-info-value {
+    font-size: 12px;
+    color: var(--text-primary);
+    font-weight: 600;
+}
+
+.gps-mono {
+    font-family: var(--font-mono);
+}
+
+/* Connection status */
+.gps-connection-status {
+    display: flex;
+    align-items: center;
+    gap: 6px;
+}
+
+.gps-status-dot {
+    width: 8px;
+    height: 8px;
+    border-radius: 50%;
+    background: var(--text-dim);
+    flex-shrink: 0;
+}
+
+.gps-status-dot.connected {
+    background: #00ff88;
+    box-shadow: 0 0 6px rgba(0, 255, 136, 0.4);
+}
+
+.gps-status-dot.waiting {
+    background: #ffaa00;
+    box-shadow: 0 0 6px rgba(255, 170, 0, 0.4);
+}
+
+.gps-status-dot.error {
+    background: #ff4444;
+    box-shadow: 0 0 6px rgba(255, 68, 68, 0.4);
+}
+
+.gps-status-text {
+    font-size: 11px;
+    color: var(--text-secondary);
+    font-family: var(--font-mono);
+}
+
+/* Fix badge */
+.gps-fix-badge {
+    display: inline-block;
+    padding: 1px 6px;
+    border-radius: 3px;
+    font-size: 10px;
+    font-weight: 700;
+    font-family: var(--font-mono);
+}
+
+.gps-fix-badge.no-fix {
+    background: rgba(255, 68, 68, 0.2);
+    color: #ff4444;
+    border: 1px solid rgba(255, 68, 68, 0.3);
+}
+
+.gps-fix-badge.fix-2d {
+    background: rgba(255, 170, 0, 0.2);
+    color: #ffaa00;
+    border: 1px solid rgba(255, 170, 0, 0.3);
+}
+
+.gps-fix-badge.fix-3d {
+    background: rgba(0, 255, 136, 0.2);
+    color: #00ff88;
+    border: 1px solid rgba(0, 255, 136, 0.3);
+}
+
+/* DOP quality indicators */
+.gps-dop-good { color: #00ff88; }
+.gps-dop-moderate { color: #ffaa00; }
+.gps-dop-poor { color: #ff4444; }
+
+/* ===== Visuals Panel ===== */
+
+.gps-visuals-container {
+    display: flex;
+    flex-direction: column;
+    gap: 16px;
+    padding: 16px;
+    height: 100%;
+    overflow-y: auto;
+}
+
+/* Top row: sky view + position info */
+.gps-visuals-top {
+    display: flex;
+    gap: 16px;
+    flex-wrap: wrap;
+}
+
+/* Sky View */
+.gps-skyview-panel {
+    flex: 1;
+    min-width: 320px;
+    background: var(--bg-card);
+    border: 1px solid var(--border-color);
+    border-radius: 6px;
+    padding: 12px;
+}
+
+.gps-skyview-panel h4 {
+    margin: 0 0 8px 0;
+    font-size: 11px;
+    color: var(--text-dim);
+    text-transform: uppercase;
+    letter-spacing: 0.5px;
+}
+
+.gps-skyview-canvas-wrap {
+    display: flex;
+    justify-content: center;
+    align-items: center;
+}
+
+#gpsSkyCanvas {
+    max-width: 100%;
+    height: auto;
+}
+
+/* Position info panel */
+.gps-position-panel {
+    flex: 1;
+    min-width: 280px;
+    background: var(--bg-card);
+    border: 1px solid var(--border-color);
+    border-radius: 6px;
+    padding: 12px;
+    display: flex;
+    flex-direction: column;
+    gap: 12px;
+}
+
+.gps-position-panel h4 {
+    margin: 0;
+    font-size: 11px;
+    color: var(--text-dim);
+    text-transform: uppercase;
+    letter-spacing: 0.5px;
+}
+
+.gps-pos-big {
+    font-family: var(--font-mono);
+    font-size: 20px;
+    font-weight: 700;
+    color: var(--accent-cyan);
+    line-height: 1.3;
+}
+
+.gps-pos-row {
+    display: flex;
+    justify-content: space-between;
+    align-items: center;
+    padding: 4px 0;
+    border-bottom: 1px solid var(--border-color);
+}
+
+.gps-pos-row:last-child {
+    border-bottom: none;
+}
+
+.gps-pos-label {
+    font-size: 10px;
+    color: var(--text-dim);
+    text-transform: uppercase;
+}
+
+.gps-pos-value {
+    font-family: var(--font-mono);
+    font-size: 13px;
+    color: var(--text-primary);
+    font-weight: 600;
+}
+
+/* Signal Strength Bars */
+.gps-signal-panel {
+    background: var(--bg-card);
+    border: 1px solid var(--border-color);
+    border-radius: 6px;
+    padding: 12px;
+}
+
+.gps-signal-panel h4 {
+    margin: 0 0 8px 0;
+    font-size: 11px;
+    color: var(--text-dim);
+    text-transform: uppercase;
+    letter-spacing: 0.5px;
+}
+
+.gps-signal-bars {
+    display: flex;
+    align-items: flex-end;
+    gap: 3px;
+    height: 140px;
+    padding: 0 4px;
+    overflow-x: auto;
+}
+
+.gps-signal-bar-wrap {
+    display: flex;
+    flex-direction: column;
+    align-items: center;
+    gap: 2px;
+    min-width: 18px;
+    height: 100%;
+    justify-content: flex-end;
+}
+
+.gps-signal-bar {
+    width: 14px;
+    border-radius: 2px 2px 0 0;
+    min-height: 2px;
+    transition: height 0.3s ease;
+}
+
+.gps-signal-bar.unused {
+    opacity: 0.4;
+}
+
+.gps-signal-prn {
+    font-size: 8px;
+    font-family: var(--font-mono);
+    color: var(--text-dim);
+    writing-mode: horizontal-tb;
+}
+
+.gps-signal-snr {
+    font-size: 7px;
+    font-family: var(--font-mono);
+    color: var(--text-secondary);
+}
+
+/* Constellation colors */
+.gps-const-gps { background-color: #00d4ff; }
+.gps-const-glonass { background-color: #00ff88; }
+.gps-const-galileo { background-color: #ff8800; }
+.gps-const-beidou { background-color: #ff4466; }
+.gps-const-sbas { background-color: #ffdd00; }
+.gps-const-qzss { background-color: #cc66ff; }
+
+/* Legend */
+.gps-legend {
+    display: flex;
+    gap: 12px;
+    flex-wrap: wrap;
+    margin-top: 8px;
+    padding-top: 8px;
+    border-top: 1px solid var(--border-color);
+}
+
+.gps-legend-item {
+    display: flex;
+    align-items: center;
+    gap: 4px;
+    font-size: 9px;
+    color: var(--text-dim);
+}
+
+.gps-legend-dot {
+    width: 8px;
+    height: 8px;
+    border-radius: 50%;
+    flex-shrink: 0;
+}
+
+/* Empty state */
+.gps-empty-state {
+    display: flex;
+    flex-direction: column;
+    align-items: center;
+    justify-content: center;
+    gap: 12px;
+    padding: 40px;
+    color: var(--text-dim);
+    text-align: center;
+}
+
+.gps-empty-state svg {
+    width: 48px;
+    height: 48px;
+    opacity: 0.3;
+}
+
+.gps-empty-state p {
+    font-size: 12px;
+    max-width: 300px;
+    line-height: 1.5;
+}
+
+/* Responsive */
+@media (max-width: 768px) {
+    .gps-visuals-top {
+        flex-direction: column;
+    }
+
+    .gps-skyview-panel,
+    .gps-position-panel {
+        min-width: unset;
+    }
+
+    .gps-pos-big {
+        font-size: 16px;
+    }
+}

static/js/components/proximity-radar.js

@@ -36,6 +36,7 @@ const ProximityRadar = (function() {
     let isHovered = false;
     let renderPending = false;
     let renderTimer = null;
+    let interactionLockUntil = 0; // timestamp: suppress renders briefly after click
 
     /**
      * Initialize the radar component
@@ -119,6 +120,36 @@ const ProximityRadar = (function() {
 
         svg = container.querySelector('svg');
 
+        // Event delegation on the devices group (survives innerHTML rebuilds)
+        const devicesGroup = svg.querySelector('.radar-devices');
+
+        devicesGroup.addEventListener('click', (e) => {
+            const deviceEl = e.target.closest('.radar-device');
+            if (!deviceEl) return;
+            const deviceKey = deviceEl.getAttribute('data-device-key');
+            if (onDeviceClick && deviceKey) {
+                // Lock out re-renders briefly so the DOM stays stable after click
+                interactionLockUntil = Date.now() + 500;
+                onDeviceClick(deviceKey);
+            }
+        });
+
+        devicesGroup.addEventListener('mouseenter', (e) => {
+            if (e.target.closest('.radar-device')) {
+                isHovered = true;
+            }
+        }, true); // capture phase so we catch enter on child elements
+
+        devicesGroup.addEventListener('mouseleave', (e) => {
+            if (e.target.closest('.radar-device')) {
+                isHovered = false;
+                if (renderPending) {
+                    renderPending = false;
+                    renderDevices();
+                }
+            }
+        }, true);
+
         // Add sweep animation
         animateSweep();
     }
@@ -165,8 +196,8 @@ const ProximityRadar = (function() {
             devices.set(device.device_key, device);
         });
 
-        // Defer render while user is hovering to prevent DOM rebuild flicker
+        // Defer render while user is hovering or interacting to prevent DOM rebuild flicker
-        if (isHovered) {
+        if (isHovered || Date.now() < interactionLockUntil) {
             renderPending = true;
             return;
         }
@@ -229,7 +260,7 @@ const ProximityRadar = (function() {
                        style="cursor: pointer;">
                         <!-- Invisible hit area to prevent hover flicker -->
                         <circle class="radar-device-hitarea" r="${hitAreaSize}" fill="transparent" />
-                        ${isSelected ? `<circle r="${dotSize + 8}" fill="none" stroke="#00d4ff" stroke-width="2" stroke-opacity="0.8">
+                        ${isSelected ? `<circle class="radar-select-ring" r="${dotSize + 8}" fill="none" stroke="#00d4ff" stroke-width="2" stroke-opacity="0.8">
                             <animate attributeName="r" values="${dotSize + 6};${dotSize + 10};${dotSize + 6}" dur="1.5s" repeatCount="indefinite"/>
                             <animate attributeName="stroke-opacity" values="0.8;0.4;0.8" dur="1.5s" repeatCount="indefinite"/>
                         </circle>` : ''}
@@ -244,24 +275,6 @@ const ProximityRadar = (function() {
         }).join('');
 
         devicesGroup.innerHTML = dots;
-
-        // Attach event handlers
-        devicesGroup.querySelectorAll('.radar-device').forEach(el => {
-            el.addEventListener('click', (e) => {
-                const deviceKey = el.getAttribute('data-device-key');
-                if (onDeviceClick && deviceKey) {
-                    onDeviceClick(deviceKey);
-                }
-            });
-            el.addEventListener('mouseenter', () => { isHovered = true; });
-            el.addEventListener('mouseleave', () => {
-                isHovered = false;
-                if (renderPending) {
-                    renderPending = false;
-                    renderDevices();
-                }
-            });
-        });
     }
 
     /**
@@ -345,19 +358,125 @@ const ProximityRadar = (function() {
     }
 
     /**
-     * Highlight a specific device on the radar
+     * Highlight a specific device on the radar (in-place update, no full re-render)
      */
     function highlightDevice(deviceKey) {
+        const prev = selectedDeviceKey;
         selectedDeviceKey = deviceKey;
-        renderDevices();
+
+        if (!svg) { return; }
+        const devicesGroup = svg.querySelector('.radar-devices');
+        if (!devicesGroup) { return; }
+
+        // Remove highlight from previously selected node
+        if (prev && prev !== deviceKey) {
+            const oldEl = devicesGroup.querySelector(`.radar-device[data-device-key="${CSS.escape(prev)}"]`);
+            if (oldEl) {
+                oldEl.classList.remove('selected');
+                // Remove animated selection ring
+                const ring = oldEl.querySelector('.radar-select-ring');
+                if (ring) ring.remove();
+                // Restore dot opacity
+                const dot = oldEl.querySelector('circle:not(.radar-device-hitarea):not(.radar-select-ring)');
+                if (dot && dot.getAttribute('fill') !== 'none' && dot.getAttribute('fill') !== 'transparent') {
+                    const device = devices.get(prev);
+                    const confidence = device ? (device.distance_confidence || 0.5) : 0.5;
+                    dot.setAttribute('fill-opacity', 0.4 + confidence * 0.5);
+                    dot.setAttribute('stroke', dot.getAttribute('fill'));
+                    dot.setAttribute('stroke-width', '1');
+                }
+            }
+        }
+
+        // Add highlight to newly selected node
+        if (deviceKey) {
+            const newEl = devicesGroup.querySelector(`.radar-device[data-device-key="${CSS.escape(deviceKey)}"]`);
+            if (newEl) {
+                applySelectionToElement(newEl, deviceKey);
+            } else {
+                // Node not in DOM yet; full render needed on next cycle
+                renderDevices();
+            }
+        }
     }
 
     /**
-     * Clear device highlighting
+     * Apply selection styling to a radar device element in-place
+     */
+    function applySelectionToElement(el, deviceKey) {
+        el.classList.add('selected');
+        const device = devices.get(deviceKey);
+        const confidence = device ? (device.distance_confidence || 0.5) : 0.5;
+        const dotSize = CONFIG.dotMinSize + (CONFIG.dotMaxSize - CONFIG.dotMinSize) * confidence;
+
+        // Update dot styling
+        const dot = el.querySelector('circle:not(.radar-device-hitarea):not(.radar-select-ring)');
+        if (dot && dot.getAttribute('fill') !== 'none' && dot.getAttribute('fill') !== 'transparent') {
+            dot.setAttribute('fill-opacity', '1');
+            dot.setAttribute('stroke', '#00d4ff');
+            dot.setAttribute('stroke-width', '2');
+        }
+
+        // Add animated selection ring if not already present
+        if (!el.querySelector('.radar-select-ring')) {
+            const ns = 'http://www.w3.org/2000/svg';
+            const ring = document.createElementNS(ns, 'circle');
+            ring.classList.add('radar-select-ring');
+            ring.setAttribute('r', dotSize + 8);
+            ring.setAttribute('fill', 'none');
+            ring.setAttribute('stroke', '#00d4ff');
+            ring.setAttribute('stroke-width', '2');
+            ring.setAttribute('stroke-opacity', '0.8');
+
+            const animR = document.createElementNS(ns, 'animate');
+            animR.setAttribute('attributeName', 'r');
+            animR.setAttribute('values', `${dotSize + 6};${dotSize + 10};${dotSize + 6}`);
+            animR.setAttribute('dur', '1.5s');
+            animR.setAttribute('repeatCount', 'indefinite');
+            ring.appendChild(animR);
+
+            const animO = document.createElementNS(ns, 'animate');
+            animO.setAttribute('attributeName', 'stroke-opacity');
+            animO.setAttribute('values', '0.8;0.4;0.8');
+            animO.setAttribute('dur', '1.5s');
+            animO.setAttribute('repeatCount', 'indefinite');
+            ring.appendChild(animO);
+
+            // Insert after the hit area
+            const hitArea = el.querySelector('.radar-device-hitarea');
+            if (hitArea && hitArea.nextSibling) {
+                el.insertBefore(ring, hitArea.nextSibling);
+            } else {
+                el.insertBefore(ring, el.firstChild);
+            }
+        }
+    }
+
+    /**
+     * Clear device highlighting (in-place update, no full re-render)
      */
     function clearHighlight() {
+        const prev = selectedDeviceKey;
         selectedDeviceKey = null;
-        renderDevices();
+
+        if (!svg || !prev) { return; }
+        const devicesGroup = svg.querySelector('.radar-devices');
+        if (!devicesGroup) { return; }
+
+        const oldEl = devicesGroup.querySelector(`.radar-device[data-device-key="${CSS.escape(prev)}"]`);
+        if (oldEl) {
+            oldEl.classList.remove('selected');
+            const ring = oldEl.querySelector('.radar-select-ring');
+            if (ring) ring.remove();
+            const dot = oldEl.querySelector('circle:not(.radar-device-hitarea):not(.radar-select-ring)');
+            if (dot && dot.getAttribute('fill') !== 'none' && dot.getAttribute('fill') !== 'transparent') {
+                const device = devices.get(prev);
+                const confidence = device ? (device.distance_confidence || 0.5) : 0.5;
+                dot.setAttribute('fill-opacity', 0.4 + confidence * 0.5);
+                dot.setAttribute('stroke', dot.getAttribute('fill'));
+                dot.setAttribute('stroke-width', '1');
+            }
+        }
     }
 
     /**

static/js/components/signal-cards.js

@@ -302,7 +302,13 @@ const SignalCards = (function() {
      */
     function formatRelativeTime(timestamp) {
         if (!timestamp) return '';
-        const date = new Date(timestamp);
+        let date = new Date(timestamp);
+        // Handle time-only strings like "HH:MM:SS" (from pager/sensor backends)
+        if (isNaN(date.getTime()) && /^\d{1,2}:\d{2}(:\d{2})?$/.test(timestamp)) {
+            const today = new Date();
+            date = new Date(today.toDateString() + ' ' + timestamp);
+        }
+        if (isNaN(date.getTime())) return timestamp;
         const now = new Date();
         const diff = Math.floor((now - date) / 1000);
 

static/js/modes/bluetooth.js

@@ -356,7 +356,9 @@ const BluetoothMode = (function() {
 
         // Update panel elements
         document.getElementById('btDetailName').textContent = device.name || formatDeviceId(device.address);
-        document.getElementById('btDetailAddress').textContent = device.address;
+        document.getElementById('btDetailAddress').textContent = isUuidAddress(device)
+            ? 'CB: ' + device.address
+            : device.address;
 
         // RSSI
         const rssiEl = document.getElementById('btDetailRssi');
@@ -458,8 +460,98 @@ const BluetoothMode = (function() {
             ? new Date(device.last_seen).toLocaleTimeString()
             : '--';
 
+        // New stat cells
+        document.getElementById('btDetailTxPower').textContent = device.tx_power != null
+            ? device.tx_power + ' dBm' : '--';
+        document.getElementById('btDetailSeenRate').textContent = device.seen_rate != null
+            ? device.seen_rate.toFixed(1) + '/min' : '--';
+
+        // Stability from variance
+        const stabilityEl = document.getElementById('btDetailStability');
+        if (device.rssi_variance != null) {
+            let stabLabel, stabColor;
+            if (device.rssi_variance <= 5) { stabLabel = 'Stable'; stabColor = '#22c55e'; }
+            else if (device.rssi_variance <= 25) { stabLabel = 'Moderate'; stabColor = '#eab308'; }
+            else { stabLabel = 'Unstable'; stabColor = '#ef4444'; }
+            stabilityEl.textContent = stabLabel;
+            stabilityEl.style.color = stabColor;
+        } else {
+            stabilityEl.textContent = '--';
+            stabilityEl.style.color = '';
+        }
+
+        // Distance with confidence
+        const distEl = document.getElementById('btDetailDistance');
+        if (device.estimated_distance_m != null) {
+            const confPct = Math.round((device.distance_confidence || 0) * 100);
+            distEl.textContent = device.estimated_distance_m.toFixed(1) + 'm ±' + confPct + '%';
+        } else {
+            distEl.textContent = '--';
+        }
+
+        // Appearance badge
+        if (device.appearance_name) {
+            badgesHtml += '<span class="bt-detail-badge flag">' + escapeHtml(device.appearance_name) + '</span>';
+            badgesEl.innerHTML = badgesHtml;
+        }
+
+        // MAC cluster indicator
+        const macClusterEl = document.getElementById('btDetailMacCluster');
+        if (macClusterEl) {
+            if (device.mac_cluster_count > 1) {
+                macClusterEl.textContent = device.mac_cluster_count + ' MACs';
+                macClusterEl.style.display = '';
+            } else {
+                macClusterEl.style.display = 'none';
+            }
+        }
+
+        // Service data inspector
+        const inspectorEl = document.getElementById('btDetailServiceInspector');
+        const inspectorContent = document.getElementById('btInspectorContent');
+        if (inspectorEl && inspectorContent) {
+            const hasData = device.manufacturer_bytes || device.appearance != null ||
+                (device.service_data && Object.keys(device.service_data).length > 0);
+            if (hasData) {
+                inspectorEl.style.display = '';
+                let inspHtml = '';
+                if (device.appearance != null) {
+                    const name = device.appearance_name || '';
+                    inspHtml += '<div class="bt-inspector-row"><span class="bt-inspector-label">Appearance</span><span class="bt-inspector-value">0x' + device.appearance.toString(16).toUpperCase().padStart(4, '0') + (name ? ' (' + escapeHtml(name) + ')' : '') + '</span></div>';
+                }
+                if (device.manufacturer_bytes) {
+                    inspHtml += '<div class="bt-inspector-row"><span class="bt-inspector-label">Mfr Data</span><span class="bt-inspector-value">' + escapeHtml(device.manufacturer_bytes) + '</span></div>';
+                }
+                if (device.service_data) {
+                    Object.entries(device.service_data).forEach(([uuid, hex]) => {
+                        inspHtml += '<div class="bt-inspector-row"><span class="bt-inspector-label">' + escapeHtml(uuid) + '</span><span class="bt-inspector-value">' + escapeHtml(hex) + '</span></div>';
+                    });
+                }
+                inspectorContent.innerHTML = inspHtml;
+            } else {
+                inspectorEl.style.display = 'none';
+            }
+        }
+
         updateWatchlistButton(device);
 
+        // IRK
+        const irkContainer = document.getElementById('btDetailIrk');
+        if (irkContainer) {
+            if (device.has_irk) {
+                irkContainer.style.display = 'block';
+                const irkVal = document.getElementById('btDetailIrkValue');
+                if (irkVal) {
+                    const label = device.irk_source_name
+                        ? device.irk_source_name + ' — ' + device.irk_hex
+                        : device.irk_hex;
+                    irkVal.textContent = label;
+                }
+            } else {
+                irkContainer.style.display = 'none';
+            }
+        }
+
         // Services
         const servicesContainer = document.getElementById('btDetailServices');
         const servicesList = document.getElementById('btDetailServicesList');
@@ -600,9 +692,25 @@ const BluetoothMode = (function() {
         if (parts.length === 6) {
             return parts[0] + ':' + parts[1] + ':...:' + parts[4] + ':' + parts[5];
         }
+        // CoreBluetooth UUID format (8-4-4-4-12)
+        if (/^[0-9A-F]{8}-[0-9A-F]{4}-/i.test(address)) {
+            return address.substring(0, 8) + '...';
+        }
         return address;
     }
 
+    function isUuidAddress(device) {
+        return device.address_type === 'uuid';
+    }
+
+    function formatAddress(device) {
+        if (!device || !device.address) return '--';
+        if (isUuidAddress(device)) {
+            return device.address.substring(0, 8) + '-...' + device.address.slice(-4);
+        }
+        return device.address;
+    }
+
     /**
      * Check system capabilities
      */
@@ -660,6 +768,12 @@ const BluetoothMode = (function() {
                 hideCapabilityWarning();
             }
 
+            // Show/hide Ubertooth option based on capabilities
+            const ubertoothOption = document.getElementById('btScanModeUbertooth');
+            if (ubertoothOption) {
+                ubertoothOption.style.display = data.has_ubertooth ? '' : 'none';
+            }
+
             if (scanModeSelect && data.preferred_backend) {
                 const option = scanModeSelect.querySelector(`option[value="${data.preferred_backend}"]`);
                 if (option) option.selected = true;
@@ -1085,7 +1199,7 @@ const BluetoothMode = (function() {
                             '</div>' +
                         '</div>' +
                         '<div style="display:flex;justify-content:space-between;margin-top:3px;">' +
-                            '<span style="font-size:9px;color:#888;font-family:monospace;">' + t.address + '</span>' +
+                            '<span style="font-size:9px;color:#888;font-family:monospace;">' + (t.address_type === 'uuid' ? formatAddress(t) : t.address) + '</span>' +
                             '<span style="font-size:9px;color:#666;">Seen ' + (t.seen_count || 0) + 'x</span>' +
                         '</div>' +
                         evidenceHtml +
@@ -1142,7 +1256,7 @@ const BluetoothMode = (function() {
 
         const displayName = device.name || formatDeviceId(device.address);
         const name = escapeHtml(displayName);
-        const addr = escapeHtml(device.address || 'Unknown');
+        const addr = escapeHtml(isUuidAddress(device) ? formatAddress(device) : (device.address || 'Unknown'));
         const mfr = device.manufacturer_name ? escapeHtml(device.manufacturer_name) : '';
         const seenCount = device.seen_count || 0;
         const deviceIdEscaped = escapeHtml(device.device_id).replace(/'/g, "\\'");
@@ -1167,6 +1281,12 @@ const BluetoothMode = (function() {
             trackerBadge = '<span class="bt-tracker-badge" style="background:' + confBg + ';color:' + confColor + ';font-size:9px;padding:1px 4px;border-radius:3px;margin-left:4px;font-weight:600;">' + typeLabel + '</span>';
         }
 
+        // IRK badge - show if paired IRK is available
+        let irkBadge = '';
+        if (device.has_irk) {
+            irkBadge = '<span class="bt-irk-badge">IRK</span>';
+        }
+
         // Risk badge - show if risk score is significant
         let riskBadge = '';
         if (riskScore >= 0.3) {
@@ -1184,9 +1304,36 @@ const BluetoothMode = (function() {
             statusDot = '<span class="bt-status-dot known"></span>';
         }
 
+        // Distance display
+        const distM = device.estimated_distance_m;
+        let distStr = '';
+        if (distM != null) {
+            distStr = '~' + distM.toFixed(1) + 'm';
+        }
+
+        // Behavioral flag badges
+        const hFlags = device.heuristic_flags || [];
+        let flagBadges = '';
+        if (device.is_persistent || hFlags.includes('persistent')) {
+            flagBadges += '<span class="bt-flag-badge persistent">PERSIST</span>';
+        }
+        if (device.is_beacon_like || hFlags.includes('beacon_like')) {
+            flagBadges += '<span class="bt-flag-badge beacon-like">BEACON</span>';
+        }
+        if (device.is_strong_stable || hFlags.includes('strong_stable')) {
+            flagBadges += '<span class="bt-flag-badge strong-stable">STABLE</span>';
+        }
+
+        // MAC cluster badge
+        let clusterBadge = '';
+        if (device.mac_cluster_count > 1) {
+            clusterBadge = '<span class="bt-mac-cluster-badge">' + device.mac_cluster_count + ' MACs</span>';
+        }
+
         // Build secondary info line
         let secondaryParts = [addr];
         if (mfr) secondaryParts.push(mfr);
+        if (distStr) secondaryParts.push(distStr);
         secondaryParts.push('Seen ' + seenCount + '×');
         if (seenBefore) secondaryParts.push('<span class="bt-history-badge">SEEN BEFORE</span>');
         // Add agent name if not Local
@@ -1205,7 +1352,10 @@ const BluetoothMode = (function() {
                     protoBadge +
                     '<span class="bt-device-name">' + name + '</span>' +
                     trackerBadge +
+                    irkBadge +
                     riskBadge +
+                    flagBadges +
+                    clusterBadge +
                 '</div>' +
                 '<div class="bt-row-right">' +
                     '<div class="bt-rssi-container">' +
@@ -1216,6 +1366,11 @@ const BluetoothMode = (function() {
                 '</div>' +
             '</div>' +
             '<div class="bt-row-secondary">' + secondaryInfo + '</div>' +
+            '<div class="bt-row-actions">' +
+                '<button class="bt-locate-btn" data-locate-id="' + escapeHtml(device.device_id) + '" onclick="event.stopPropagation(); BluetoothMode.locateById(this.dataset.locateId)">' +
+                    '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><circle cx="12" cy="10" r="3"/><path d="M12 21.7C17.3 17 20 13 20 10a8 8 0 1 0-16 0c0 3 2.7 7 8 11.7z"/></svg>' +
+                    'Locate</button>' +
+            '</div>' +
         '</div>';
     }
 
@@ -1295,6 +1450,18 @@ const BluetoothMode = (function() {
         }
     }
 
+    /**
+     * Toggle the service data inspector panel
+     */
+    function toggleServiceInspector() {
+        const content = document.getElementById('btInspectorContent');
+        const arrow = document.getElementById('btInspectorArrow');
+        if (!content) return;
+        const open = content.style.display === 'none';
+        content.style.display = open ? '' : 'none';
+        if (arrow) arrow.classList.toggle('open', open);
+    }
+
     // ==========================================================================
     // Agent Handling
     // ==========================================================================
@@ -1391,6 +1558,48 @@ const BluetoothMode = (function() {
         updateRadar();
     }
 
+    /**
+     * Hand off a device to BT Locate mode by device_id lookup.
+     */
+    function locateById(deviceId) {
+        console.log('[BT] locateById called with:', deviceId);
+        const device = devices.get(deviceId);
+        if (!device) {
+            console.warn('[BT] Device not found in map for id:', deviceId);
+            return;
+        }
+        doLocateHandoff(device);
+    }
+
+    /**
+     * Hand off the currently selected device to BT Locate mode.
+     */
+    function locateDevice() {
+        if (!selectedDeviceId) return;
+        const device = devices.get(selectedDeviceId);
+        if (!device) return;
+        doLocateHandoff(device);
+    }
+
+    function doLocateHandoff(device) {
+        console.log('[BT] doLocateHandoff, BtLocate defined:', typeof BtLocate !== 'undefined');
+        if (typeof BtLocate !== 'undefined') {
+            BtLocate.handoff({
+                device_id: device.device_id,
+                mac_address: device.address,
+                address_type: device.address_type || null,
+                irk_hex: device.irk_hex || null,
+                known_name: device.name || null,
+                known_manufacturer: device.manufacturer_name || null,
+                last_known_rssi: device.rssi_current,
+                tx_power: device.tx_power || null,
+                appearance_name: device.appearance_name || null,
+                fingerprint_id: device.fingerprint_id || null,
+                mac_cluster_count: device.mac_cluster_count || 0
+            });
+        }
+    }
+
     // Public API
     return {
         init,
@@ -1404,6 +1613,9 @@ const BluetoothMode = (function() {
         clearSelection,
         copyAddress,
         toggleWatchlist,
+        locateDevice,
+        locateById,
+        toggleServiceInspector,
 
         // Agent handling
         handleAgentChange,

static/js/modes/bt_locate.js

@@ -0,0 +1,749 @@
+/**
+ * BT Locate — Bluetooth SAR Device Location Mode
+ * GPS-tagged signal trail mapping with proximity audio alerts.
+ */
+const BtLocate = (function() {
+    'use strict';
+
+    let eventSource = null;
+    let map = null;
+    let mapMarkers = [];
+    let trailLine = null;
+    let rssiHistory = [];
+    const MAX_RSSI_POINTS = 60;
+    let chartCanvas = null;
+    let chartCtx = null;
+    let currentEnvironment = 'OUTDOOR';
+    let audioCtx = null;
+    let audioEnabled = false;
+    let beepTimer = null;
+    let initialized = false;
+    let handoffData = null;
+    let pollTimer = null;
+    let durationTimer = null;
+    let sessionStartedAt = null;
+    let lastDetectionCount = 0;
+
+    function init() {
+        if (initialized) {
+            // Re-invalidate map on re-entry and ensure tiles are present
+            if (map) {
+                setTimeout(() => {
+                    map.invalidateSize();
+                    // Re-apply user's tile layer if tiles were lost
+                    let hasTiles = false;
+                    map.eachLayer(layer => {
+                        if (layer instanceof L.TileLayer) hasTiles = true;
+                    });
+                    if (!hasTiles && typeof Settings !== 'undefined' && Settings.createTileLayer) {
+                        Settings.createTileLayer().addTo(map);
+                    }
+                }, 150);
+            }
+            checkStatus();
+            return;
+        }
+
+        // Init map
+        const mapEl = document.getElementById('btLocateMap');
+        if (mapEl && typeof L !== 'undefined') {
+            map = L.map('btLocateMap', {
+                center: [0, 0],
+                zoom: 2,
+                zoomControl: true,
+            });
+            // Use tile provider from user settings
+            if (typeof Settings !== 'undefined' && Settings.createTileLayer) {
+                Settings.createTileLayer().addTo(map);
+                Settings.registerMap(map);
+            } else {
+                L.tileLayer('https://{s}.basemaps.cartocdn.com/dark_all/{z}/{x}/{y}{r}.png', {
+                    maxZoom: 19,
+                    attribution: '© OSM © CARTO'
+                }).addTo(map);
+            }
+            setTimeout(() => map.invalidateSize(), 100);
+        }
+
+        // Init RSSI chart canvas
+        chartCanvas = document.getElementById('btLocateRssiChart');
+        if (chartCanvas) {
+            chartCtx = chartCanvas.getContext('2d');
+        }
+
+        checkStatus();
+        initialized = true;
+    }
+
+    function checkStatus() {
+        fetch('/bt_locate/status')
+            .then(r => r.json())
+            .then(data => {
+                if (data.active) {
+                    sessionStartedAt = data.started_at ? new Date(data.started_at).getTime() : Date.now();
+                    showActiveUI();
+                    updateScanStatus(data);
+                    if (!eventSource) connectSSE();
+                    // Restore trail from server
+                    fetch('/bt_locate/trail')
+                        .then(r => r.json())
+                        .then(trail => {
+                            if (trail.gps_trail) {
+                                trail.gps_trail.forEach(p => addMapMarker(p));
+                            }
+                            updateStats(data.detection_count, data.gps_trail_count);
+                        });
+                }
+            })
+            .catch(() => {});
+    }
+
+    function start() {
+        const mac = document.getElementById('btLocateMac')?.value.trim();
+        const namePattern = document.getElementById('btLocateNamePattern')?.value.trim();
+        const irk = document.getElementById('btLocateIrk')?.value.trim();
+
+        const body = { environment: currentEnvironment };
+        if (mac) body.mac_address = mac;
+        if (namePattern) body.name_pattern = namePattern;
+        if (irk) body.irk_hex = irk;
+        if (handoffData?.device_id) body.device_id = handoffData.device_id;
+        if (handoffData?.known_name) body.known_name = handoffData.known_name;
+        if (handoffData?.known_manufacturer) body.known_manufacturer = handoffData.known_manufacturer;
+        if (handoffData?.last_known_rssi) body.last_known_rssi = handoffData.last_known_rssi;
+
+        // Include user location as fallback when GPS unavailable
+        const userLat = localStorage.getItem('observerLat');
+        const userLon = localStorage.getItem('observerLon');
+        if (userLat && userLon) {
+            body.fallback_lat = parseFloat(userLat);
+            body.fallback_lon = parseFloat(userLon);
+        }
+
+        console.log('[BtLocate] Starting with body:', body);
+
+        if (!body.mac_address && !body.name_pattern && !body.irk_hex && !body.device_id) {
+            alert('Please provide at least a MAC address, name pattern, IRK, or use hand-off from Bluetooth mode.');
+            return;
+        }
+
+        fetch('/bt_locate/start', {
+            method: 'POST',
+            headers: { 'Content-Type': 'application/json' },
+            body: JSON.stringify(body),
+        })
+            .then(r => r.json())
+            .then(data => {
+                if (data.status === 'started') {
+                    sessionStartedAt = data.session?.started_at ? new Date(data.session.started_at).getTime() : Date.now();
+                    showActiveUI();
+                    connectSSE();
+                    rssiHistory = [];
+                    updateScanStatus(data.session);
+                    // Restore any existing trail (e.g. from a stop/start cycle)
+                    restoreTrail();
+                }
+            })
+            .catch(err => console.error('[BtLocate] Start error:', err));
+    }
+
+    function stop() {
+        fetch('/bt_locate/stop', { method: 'POST' })
+            .then(r => r.json())
+            .then(() => {
+                showIdleUI();
+                disconnectSSE();
+                stopAudio();
+            })
+            .catch(err => console.error('[BtLocate] Stop error:', err));
+    }
+
+    function showActiveUI() {
+        const startBtn = document.getElementById('btLocateStartBtn');
+        const stopBtn = document.getElementById('btLocateStopBtn');
+        if (startBtn) startBtn.style.display = 'none';
+        if (stopBtn) stopBtn.style.display = 'inline-block';
+        show('btLocateHud');
+    }
+
+    function showIdleUI() {
+        const startBtn = document.getElementById('btLocateStartBtn');
+        const stopBtn = document.getElementById('btLocateStopBtn');
+        if (startBtn) startBtn.style.display = 'inline-block';
+        if (stopBtn) stopBtn.style.display = 'none';
+        hide('btLocateHud');
+        hide('btLocateScanStatus');
+    }
+
+    function updateScanStatus(statusData) {
+        const el = document.getElementById('btLocateScanStatus');
+        const dot = document.getElementById('btLocateScanDot');
+        const text = document.getElementById('btLocateScanText');
+        if (!el) return;
+
+        el.style.display = '';
+        if (statusData && statusData.scanner_running) {
+            if (dot) dot.style.background = '#22c55e';
+            if (text) text.textContent = 'BT scanner active';
+        } else {
+            if (dot) dot.style.background = '#f97316';
+            if (text) text.textContent = 'BT scanner not running — waiting...';
+        }
+    }
+
+    function show(id) { const el = document.getElementById(id); if (el) el.style.display = ''; }
+    function hide(id) { const el = document.getElementById(id); if (el) el.style.display = 'none'; }
+
+    function connectSSE() {
+        if (eventSource) eventSource.close();
+        console.log('[BtLocate] Connecting SSE stream');
+        eventSource = new EventSource('/bt_locate/stream');
+
+        eventSource.addEventListener('detection', function(e) {
+            try {
+                const event = JSON.parse(e.data);
+                console.log('[BtLocate] Detection event:', event);
+                handleDetection(event);
+            } catch (err) {
+                console.error('[BtLocate] Parse error:', err);
+            }
+        });
+
+        eventSource.addEventListener('session_ended', function() {
+            showIdleUI();
+            disconnectSSE();
+        });
+
+        eventSource.onerror = function() {
+            console.warn('[BtLocate] SSE error, polling fallback active');
+        };
+
+        // Start polling fallback (catches data even if SSE fails)
+        startPolling();
+    }
+
+    function disconnectSSE() {
+        if (eventSource) {
+            eventSource.close();
+            eventSource = null;
+        }
+        stopPolling();
+    }
+
+    function startPolling() {
+        stopPolling();
+        lastDetectionCount = 0;
+        pollTimer = setInterval(pollStatus, 3000);
+        startDurationTimer();
+    }
+
+    function stopPolling() {
+        if (pollTimer) {
+            clearInterval(pollTimer);
+            pollTimer = null;
+        }
+        stopDurationTimer();
+    }
+
+    function startDurationTimer() {
+        stopDurationTimer();
+        durationTimer = setInterval(updateDuration, 1000);
+    }
+
+    function stopDurationTimer() {
+        if (durationTimer) {
+            clearInterval(durationTimer);
+            durationTimer = null;
+        }
+    }
+
+    function updateDuration() {
+        if (!sessionStartedAt) return;
+        const elapsed = Math.round((Date.now() - sessionStartedAt) / 1000);
+        const mins = Math.floor(elapsed / 60);
+        const secs = elapsed % 60;
+        const timeEl = document.getElementById('btLocateSessionTime');
+        if (timeEl) timeEl.textContent = mins + ':' + String(secs).padStart(2, '0');
+    }
+
+    function pollStatus() {
+        fetch('/bt_locate/status')
+            .then(r => r.json())
+            .then(data => {
+                if (!data.active) {
+                    showIdleUI();
+                    disconnectSSE();
+                    return;
+                }
+
+                updateScanStatus(data);
+                updateHudInfo(data);
+
+                // Show diagnostics
+                const diagEl = document.getElementById('btLocateDiag');
+                if (diagEl) {
+                    let diag = 'Polls: ' + (data.poll_count || 0) +
+                        (data.poll_thread_alive === false ? ' DEAD' : '') +
+                        ' | Scan: ' + (data.scanner_running ? 'Y' : 'N') +
+                        ' | Devices: ' + (data.scanner_device_count || 0) +
+                        ' | Det: ' + (data.detection_count || 0);
+                    // Show debug device sample if no detections
+                    if (data.detection_count === 0 && data.debug_devices && data.debug_devices.length > 0) {
+                        const matched = data.debug_devices.filter(d => d.match);
+                        const sample = data.debug_devices.slice(0, 3).map(d =>
+                            (d.name || '?') + '|' + (d.id || '').substring(0, 12) + ':' + (d.match ? 'Y' : 'N')
+                        ).join(', ');
+                        diag += ' | Match:' + matched.length + '/' + data.debug_devices.length + ' [' + sample + ']';
+                    }
+                    diagEl.textContent = diag;
+                }
+
+                // If detection count increased, fetch new trail points
+                if (data.detection_count > lastDetectionCount) {
+                    lastDetectionCount = data.detection_count;
+                    fetch('/bt_locate/trail')
+                        .then(r => r.json())
+                        .then(trail => {
+                            if (trail.trail && trail.trail.length > 0) {
+                                const latest = trail.trail[trail.trail.length - 1];
+                                handleDetection({ data: latest });
+                            }
+                            updateStats(data.detection_count, data.gps_trail_count);
+                        });
+                }
+            })
+            .catch(() => {});
+    }
+
+    function updateHudInfo(data) {
+        // Target info
+        const targetEl = document.getElementById('btLocateTargetInfo');
+        if (targetEl && data.target) {
+            const t = data.target;
+            const name = t.known_name || t.name_pattern || '';
+            const addr = t.mac_address || t.device_id || '';
+            const addrDisplay = formatAddr(addr);
+            targetEl.textContent = name ? (name + (addrDisplay ? ' (' + addrDisplay + ')' : '')) : addrDisplay || '--';
+        }
+
+        // Environment info
+        const envEl = document.getElementById('btLocateEnvInfo');
+        if (envEl) {
+            const envNames = { FREE_SPACE: 'Open Field', OUTDOOR: 'Outdoor', INDOOR: 'Indoor', CUSTOM: 'Custom' };
+            envEl.textContent = (envNames[data.environment] || data.environment) + ' n=' + (data.path_loss_exponent || '?');
+        }
+
+        // GPS status
+        const gpsEl = document.getElementById('btLocateGpsStatus');
+        if (gpsEl) {
+            const src = data.gps_source || 'none';
+            if (src === 'live') gpsEl.textContent = 'GPS: Live';
+            else if (src === 'manual') gpsEl.textContent = 'GPS: Manual';
+            else gpsEl.textContent = 'GPS: None';
+        }
+
+        // Last seen
+        const lastEl = document.getElementById('btLocateLastSeen');
+        if (lastEl) {
+            if (data.last_detection) {
+                const ago = Math.round((Date.now() - new Date(data.last_detection).getTime()) / 1000);
+                lastEl.textContent = 'Last: ' + (ago < 60 ? ago + 's ago' : Math.floor(ago / 60) + 'm ago');
+            } else {
+                lastEl.textContent = 'Last: --';
+            }
+        }
+
+        // Session start time (duration handled by 1s timer)
+        if (data.started_at && !sessionStartedAt) {
+            sessionStartedAt = new Date(data.started_at).getTime();
+        }
+    }
+
+    function handleDetection(event) {
+        const d = event.data;
+        if (!d) return;
+
+        // Update proximity UI
+        const bandEl = document.getElementById('btLocateBand');
+        const distEl = document.getElementById('btLocateDistance');
+        const rssiEl = document.getElementById('btLocateRssi');
+        const rssiEmaEl = document.getElementById('btLocateRssiEma');
+
+        if (bandEl) {
+            bandEl.textContent = d.proximity_band;
+            bandEl.className = 'btl-hud-band ' + d.proximity_band.toLowerCase();
+        }
+        if (distEl) distEl.textContent = d.estimated_distance.toFixed(1);
+        if (rssiEl) rssiEl.textContent = d.rssi;
+        if (rssiEmaEl) rssiEmaEl.textContent = d.rssi_ema.toFixed(1);
+
+        // RSSI sparkline
+        rssiHistory.push(d.rssi);
+        if (rssiHistory.length > MAX_RSSI_POINTS) rssiHistory.shift();
+        drawRssiChart();
+
+        // Map marker
+        if (d.lat != null && d.lon != null) {
+            addMapMarker(d);
+        }
+
+        // Update stats
+        const detCountEl = document.getElementById('btLocateDetectionCount');
+        const gpsCountEl = document.getElementById('btLocateGpsCount');
+        if (detCountEl) {
+            const cur = parseInt(detCountEl.textContent) || 0;
+            detCountEl.textContent = cur + 1;
+        }
+        if (gpsCountEl && d.lat != null) {
+            const cur = parseInt(gpsCountEl.textContent) || 0;
+            gpsCountEl.textContent = cur + 1;
+        }
+
+        // Audio
+        if (audioEnabled) playProximityTone(d.rssi);
+    }
+
+    function updateStats(detections, gpsPoints) {
+        const detCountEl = document.getElementById('btLocateDetectionCount');
+        const gpsCountEl = document.getElementById('btLocateGpsCount');
+        if (detCountEl) detCountEl.textContent = detections || 0;
+        if (gpsCountEl) gpsCountEl.textContent = gpsPoints || 0;
+    }
+
+    function addMapMarker(point) {
+        if (!map || point.lat == null || point.lon == null) return;
+
+        const band = (point.proximity_band || 'FAR').toLowerCase();
+        const colors = { immediate: '#ef4444', near: '#f97316', far: '#eab308' };
+        const sizes = { immediate: 8, near: 6, far: 5 };
+        const color = colors[band] || '#eab308';
+        const radius = sizes[band] || 5;
+
+        const marker = L.circleMarker([point.lat, point.lon], {
+            radius: radius,
+            fillColor: color,
+            color: '#fff',
+            weight: 1,
+            opacity: 0.9,
+            fillOpacity: 0.8,
+        }).addTo(map);
+
+        marker.bindPopup(
+            '<div style="font-family:monospace;font-size:11px;">' +
+            '<b>' + point.proximity_band + '</b><br>' +
+            'RSSI: ' + point.rssi + ' dBm<br>' +
+            'Distance: ~' + point.estimated_distance.toFixed(1) + ' m<br>' +
+            'Time: ' + new Date(point.timestamp).toLocaleTimeString() +
+            '</div>'
+        );
+
+        mapMarkers.push(marker);
+        map.panTo([point.lat, point.lon]);
+
+        // Update trail line
+        const latlngs = mapMarkers.map(m => m.getLatLng());
+        if (trailLine) {
+            trailLine.setLatLngs(latlngs);
+        } else if (latlngs.length >= 2) {
+            trailLine = L.polyline(latlngs, {
+                color: 'rgba(0,255,136,0.5)',
+                weight: 2,
+                dashArray: '4 4',
+            }).addTo(map);
+        }
+    }
+
+    function restoreTrail() {
+        fetch('/bt_locate/trail')
+            .then(r => r.json())
+            .then(trail => {
+                if (trail.gps_trail && trail.gps_trail.length > 0) {
+                    clearMapMarkers();
+                    trail.gps_trail.forEach(p => addMapMarker(p));
+                }
+                if (trail.trail && trail.trail.length > 0) {
+                    // Restore RSSI history from trail
+                    rssiHistory = trail.trail.map(p => p.rssi).slice(-MAX_RSSI_POINTS);
+                    drawRssiChart();
+                    // Update HUD with latest detection
+                    const latest = trail.trail[trail.trail.length - 1];
+                    handleDetection({ data: latest });
+                }
+            })
+            .catch(() => {});
+    }
+
+    function clearMapMarkers() {
+        mapMarkers.forEach(m => map?.removeLayer(m));
+        mapMarkers = [];
+        if (trailLine) {
+            map?.removeLayer(trailLine);
+            trailLine = null;
+        }
+    }
+
+    function drawRssiChart() {
+        if (!chartCtx || !chartCanvas) return;
+
+        const w = chartCanvas.width = chartCanvas.parentElement.clientWidth - 16;
+        const h = chartCanvas.height = chartCanvas.parentElement.clientHeight - 24;
+        chartCtx.clearRect(0, 0, w, h);
+
+        if (rssiHistory.length < 2) return;
+
+        // RSSI range: -100 to -20
+        const minR = -100, maxR = -20;
+        const range = maxR - minR;
+
+        // Grid lines
+        chartCtx.strokeStyle = 'rgba(255,255,255,0.05)';
+        chartCtx.lineWidth = 1;
+        [-30, -50, -70, -90].forEach(v => {
+            const y = h - ((v - minR) / range) * h;
+            chartCtx.beginPath();
+            chartCtx.moveTo(0, y);
+            chartCtx.lineTo(w, y);
+            chartCtx.stroke();
+        });
+
+        // Draw RSSI line
+        const step = w / (MAX_RSSI_POINTS - 1);
+        chartCtx.beginPath();
+        chartCtx.strokeStyle = '#00ff88';
+        chartCtx.lineWidth = 2;
+
+        rssiHistory.forEach((rssi, i) => {
+            const x = i * step;
+            const y = h - ((rssi - minR) / range) * h;
+            if (i === 0) chartCtx.moveTo(x, y);
+            else chartCtx.lineTo(x, y);
+        });
+        chartCtx.stroke();
+
+        // Fill under
+        const lastIdx = rssiHistory.length - 1;
+        chartCtx.lineTo(lastIdx * step, h);
+        chartCtx.lineTo(0, h);
+        chartCtx.closePath();
+        chartCtx.fillStyle = 'rgba(0,255,136,0.08)';
+        chartCtx.fill();
+    }
+
+    // Audio proximity tone (Web Audio API)
+    function playTone(freq, duration) {
+        if (!audioCtx || audioCtx.state !== 'running') return;
+        const osc = audioCtx.createOscillator();
+        const gain = audioCtx.createGain();
+        osc.connect(gain);
+        gain.connect(audioCtx.destination);
+        osc.frequency.value = freq;
+        osc.type = 'sine';
+        gain.gain.value = 0.2;
+        gain.gain.exponentialRampToValueAtTime(0.001, audioCtx.currentTime + duration);
+        osc.start();
+        osc.stop(audioCtx.currentTime + duration);
+    }
+
+    function playProximityTone(rssi) {
+        if (!audioCtx || audioCtx.state !== 'running') return;
+        // Stronger signal = higher pitch and shorter beep
+        const strength = Math.max(0, Math.min(1, (rssi + 100) / 70));
+        const freq = 400 + strength * 800;  // 400-1200 Hz
+        const duration = 0.06 + (1 - strength) * 0.12;
+        playTone(freq, duration);
+    }
+
+    function toggleAudio() {
+        const cb = document.getElementById('btLocateAudioEnable');
+        audioEnabled = cb?.checked || false;
+        if (audioEnabled) {
+            // Create AudioContext on user gesture (required by browser policy)
+            if (!audioCtx) {
+                try {
+                    audioCtx = new (window.AudioContext || window.webkitAudioContext)();
+                } catch (e) {
+                    console.error('[BtLocate] AudioContext creation failed:', e);
+                    return;
+                }
+            }
+            // Resume must happen within a user gesture handler
+            const ctx = audioCtx;
+            ctx.resume().then(() => {
+                console.log('[BtLocate] AudioContext state:', ctx.state);
+                // Confirmation beep so user knows audio is working
+                playTone(600, 0.08);
+            });
+        } else {
+            stopAudio();
+        }
+    }
+
+    function stopAudio() {
+        audioEnabled = false;
+        const cb = document.getElementById('btLocateAudioEnable');
+        if (cb) cb.checked = false;
+    }
+
+    function setEnvironment(env) {
+        currentEnvironment = env;
+        document.querySelectorAll('.btl-env-btn').forEach(btn => {
+            btn.classList.toggle('active', btn.dataset.env === env);
+        });
+        // Push to running session if active
+        fetch('/bt_locate/status').then(r => r.json()).then(data => {
+            if (data.active) {
+                fetch('/bt_locate/environment', {
+                    method: 'POST',
+                    headers: { 'Content-Type': 'application/json' },
+                    body: JSON.stringify({ environment: env }),
+                }).then(r => r.json()).then(res => {
+                    console.log('[BtLocate] Environment updated:', res);
+                });
+            }
+        }).catch(() => {});
+    }
+
+    function isUuid(addr) {
+        return addr && /^[0-9A-F]{8}-[0-9A-F]{4}-/i.test(addr);
+    }
+
+    function formatAddr(addr) {
+        if (!addr) return '';
+        if (isUuid(addr)) return addr.substring(0, 8) + '-...' + addr.slice(-4);
+        return addr;
+    }
+
+    function handoff(deviceInfo) {
+        console.log('[BtLocate] Handoff received:', deviceInfo);
+        handoffData = deviceInfo;
+
+        // Populate fields
+        if (deviceInfo.mac_address) {
+            const macInput = document.getElementById('btLocateMac');
+            if (macInput) macInput.value = deviceInfo.mac_address;
+        }
+
+        // Show handoff card
+        const card = document.getElementById('btLocateHandoffCard');
+        const nameEl = document.getElementById('btLocateHandoffName');
+        const metaEl = document.getElementById('btLocateHandoffMeta');
+        if (card) card.style.display = '';
+        if (nameEl) nameEl.textContent = deviceInfo.known_name || formatAddr(deviceInfo.mac_address) || 'Unknown';
+        if (metaEl) {
+            const parts = [];
+            if (deviceInfo.mac_address) parts.push(formatAddr(deviceInfo.mac_address));
+            if (deviceInfo.known_manufacturer) parts.push(deviceInfo.known_manufacturer);
+            if (deviceInfo.last_known_rssi != null) parts.push(deviceInfo.last_known_rssi + ' dBm');
+            metaEl.textContent = parts.join(' \u00b7 ');
+        }
+
+        // Auto-fill IRK if available from scanner
+        if (deviceInfo.irk_hex) {
+            const irkInput = document.getElementById('btLocateIrk');
+            if (irkInput) irkInput.value = deviceInfo.irk_hex;
+        }
+
+        // Switch to bt_locate mode
+        if (typeof switchMode === 'function') {
+            switchMode('bt_locate');
+        }
+    }
+
+    function clearHandoff() {
+        handoffData = null;
+        const card = document.getElementById('btLocateHandoffCard');
+        if (card) card.style.display = 'none';
+    }
+
+    function fetchPairedIrks() {
+        const picker = document.getElementById('btLocateIrkPicker');
+        const status = document.getElementById('btLocateIrkPickerStatus');
+        const list = document.getElementById('btLocateIrkPickerList');
+        const btn = document.getElementById('btLocateDetectIrkBtn');
+        if (!picker || !status || !list) return;
+
+        // Toggle off if already visible
+        if (picker.style.display !== 'none') {
+            picker.style.display = 'none';
+            return;
+        }
+
+        picker.style.display = '';
+        list.innerHTML = '';
+        status.textContent = 'Scanning paired devices...';
+        status.style.display = '';
+        if (btn) btn.disabled = true;
+
+        fetch('/bt_locate/paired_irks')
+            .then(r => r.json())
+            .then(data => {
+                if (btn) btn.disabled = false;
+                const devices = data.devices || [];
+
+                if (devices.length === 0) {
+                    status.textContent = 'No paired devices with IRKs found';
+                    return;
+                }
+
+                status.style.display = 'none';
+                list.innerHTML = '';
+
+                devices.forEach(dev => {
+                    const item = document.createElement('div');
+                    item.className = 'btl-irk-picker-item';
+                    item.innerHTML =
+                        '<div class="btl-irk-picker-name">' + (dev.name || 'Unknown Device') + '</div>' +
+                        '<div class="btl-irk-picker-meta">' + dev.address + ' \u00b7 ' + (dev.address_type || '') + '</div>';
+                    item.addEventListener('click', function() {
+                        selectPairedIrk(dev);
+                    });
+                    list.appendChild(item);
+                });
+            })
+            .catch(err => {
+                if (btn) btn.disabled = false;
+                console.error('[BtLocate] Failed to fetch paired IRKs:', err);
+                status.textContent = 'Failed to read paired devices';
+            });
+    }
+
+    function selectPairedIrk(dev) {
+        const irkInput = document.getElementById('btLocateIrk');
+        const nameInput = document.getElementById('btLocateNamePattern');
+        const picker = document.getElementById('btLocateIrkPicker');
+
+        if (irkInput) irkInput.value = dev.irk_hex;
+        if (nameInput && dev.name && !nameInput.value) nameInput.value = dev.name;
+        if (picker) picker.style.display = 'none';
+    }
+
+    function clearTrail() {
+        fetch('/bt_locate/clear_trail', { method: 'POST' })
+            .then(r => r.json())
+            .then(() => {
+                clearMapMarkers();
+                rssiHistory = [];
+                drawRssiChart();
+                updateStats(0, 0);
+            })
+            .catch(err => console.error('[BtLocate] Clear trail error:', err));
+    }
+
+    function invalidateMap() {
+        if (map) map.invalidateSize();
+    }
+
+    return {
+        init,
+        start,
+        stop,
+        handoff,
+        clearHandoff,
+        setEnvironment,
+        toggleAudio,
+        clearTrail,
+        handleDetection,
+        invalidateMap,
+        fetchPairedIrks,
+    };
+})();

static/js/modes/gps.js

@@ -0,0 +1,406 @@
+/**
+ * GPS Mode
+ * Live GPS data display with satellite sky view, signal strength bars,
+ * position/velocity/DOP readout. Connects to gpsd via backend SSE stream.
+ */
+
+const GPS = (function() {
+    let connected = false;
+    let lastPosition = null;
+    let lastSky = null;
+
+    // Constellation color map
+    const CONST_COLORS = {
+        'GPS':     '#00d4ff',
+        'GLONASS': '#00ff88',
+        'Galileo': '#ff8800',
+        'BeiDou':  '#ff4466',
+        'SBAS':    '#ffdd00',
+        'QZSS':    '#cc66ff',
+    };
+
+    function init() {
+        drawEmptySkyView();
+        connect();
+    }
+
+    function connect() {
+        updateConnectionUI(false, false, 'connecting');
+        fetch('/gps/auto-connect', { method: 'POST' })
+            .then(r => r.json())
+            .then(data => {
+                if (data.status === 'connected') {
+                    connected = true;
+                    updateConnectionUI(true, data.has_fix);
+                    if (data.position) {
+                        lastPosition = data.position;
+                        updatePositionUI(data.position);
+                    }
+                    if (data.sky) {
+                        lastSky = data.sky;
+                        updateSkyUI(data.sky);
+                    }
+                    subscribeToStream();
+                    // Ensure the global GPS stream is running
+                    if (typeof startGpsStream === 'function' && !gpsEventSource) {
+                        startGpsStream();
+                    }
+                } else {
+                    connected = false;
+                    updateConnectionUI(false, false, 'error', data.message || 'gpsd not available');
+                }
+            })
+            .catch(() => {
+                connected = false;
+                updateConnectionUI(false, false, 'error', 'Connection failed — is the server running?');
+            });
+    }
+
+    function disconnect() {
+        unsubscribeFromStream();
+        fetch('/gps/stop', { method: 'POST' })
+            .then(() => {
+                connected = false;
+                updateConnectionUI(false);
+            });
+    }
+
+    function onGpsStreamData(data) {
+        if (!connected) return;
+        if (data.type === 'position') {
+            lastPosition = data;
+            updatePositionUI(data);
+            updateConnectionUI(true, true);
+        } else if (data.type === 'sky') {
+            lastSky = data;
+            updateSkyUI(data);
+        }
+    }
+
+    function subscribeToStream() {
+        // Subscribe to the global GPS stream instead of opening a separate SSE connection
+        if (typeof addGpsStreamSubscriber === 'function') {
+            addGpsStreamSubscriber(onGpsStreamData);
+        }
+    }
+
+    function unsubscribeFromStream() {
+        if (typeof removeGpsStreamSubscriber === 'function') {
+            removeGpsStreamSubscriber(onGpsStreamData);
+        }
+    }
+
+    // ========================
+    // UI Updates
+    // ========================
+
+    function updateConnectionUI(isConnected, hasFix, state, message) {
+        const dot = document.getElementById('gpsStatusDot');
+        const text = document.getElementById('gpsStatusText');
+        const connectBtn = document.getElementById('gpsConnectBtn');
+        const disconnectBtn = document.getElementById('gpsDisconnectBtn');
+        const devicePath = document.getElementById('gpsDevicePath');
+
+        if (dot) {
+            dot.className = 'gps-status-dot';
+            if (state === 'connecting') dot.classList.add('waiting');
+            else if (state === 'error') dot.classList.add('error');
+            else if (isConnected && hasFix) dot.classList.add('connected');
+            else if (isConnected) dot.classList.add('waiting');
+        }
+        if (text) {
+            if (state === 'connecting') text.textContent = 'Connecting...';
+            else if (state === 'error') text.textContent = message || 'Connection failed';
+            else if (isConnected && hasFix) text.textContent = 'Connected (Fix)';
+            else if (isConnected) text.textContent = 'Connected (No Fix)';
+            else text.textContent = 'Disconnected';
+        }
+        if (connectBtn) {
+            connectBtn.style.display = isConnected ? 'none' : '';
+            connectBtn.disabled = state === 'connecting';
+        }
+        if (disconnectBtn) disconnectBtn.style.display = isConnected ? '' : 'none';
+        if (devicePath) devicePath.textContent = isConnected ? 'gpsd://localhost:2947' : '';
+    }
+
+    function updatePositionUI(pos) {
+        // Sidebar fields
+        setText('gpsLat', pos.latitude != null ? pos.latitude.toFixed(6) + '\u00b0' : '---');
+        setText('gpsLon', pos.longitude != null ? pos.longitude.toFixed(6) + '\u00b0' : '---');
+        setText('gpsAlt', pos.altitude != null ? pos.altitude.toFixed(1) + ' m' : '---');
+        setText('gpsSpeed', pos.speed != null ? (pos.speed * 3.6).toFixed(1) + ' km/h' : '---');
+        setText('gpsHeading', pos.heading != null ? pos.heading.toFixed(1) + '\u00b0' : '---');
+        setText('gpsClimb', pos.climb != null ? pos.climb.toFixed(2) + ' m/s' : '---');
+
+        // Fix type
+        const fixEl = document.getElementById('gpsFixType');
+        if (fixEl) {
+            const fq = pos.fix_quality;
+            if (fq === 3) fixEl.innerHTML = '<span class="gps-fix-badge fix-3d">3D FIX</span>';
+            else if (fq === 2) fixEl.innerHTML = '<span class="gps-fix-badge fix-2d">2D FIX</span>';
+            else fixEl.innerHTML = '<span class="gps-fix-badge no-fix">NO FIX</span>';
+        }
+
+        // Error estimates
+        const eph = (pos.epx != null && pos.epy != null) ? Math.sqrt(pos.epx * pos.epx + pos.epy * pos.epy) : null;
+        setText('gpsEph', eph != null ? eph.toFixed(1) + ' m' : '---');
+        setText('gpsEpv', pos.epv != null ? pos.epv.toFixed(1) + ' m' : '---');
+        setText('gpsEps', pos.eps != null ? pos.eps.toFixed(2) + ' m/s' : '---');
+
+        // GPS time
+        if (pos.timestamp) {
+            const t = new Date(pos.timestamp);
+            setText('gpsTime', t.toISOString().replace('T', ' ').replace(/\.\d+Z$/, ' UTC'));
+        }
+
+        // Visuals: position panel
+        setText('gpsVisPosLat', pos.latitude != null ? pos.latitude.toFixed(6) + '\u00b0' : '---');
+        setText('gpsVisPosLon', pos.longitude != null ? pos.longitude.toFixed(6) + '\u00b0' : '---');
+        setText('gpsVisPosAlt', pos.altitude != null ? pos.altitude.toFixed(1) + ' m' : '---');
+        setText('gpsVisPosSpeed', pos.speed != null ? (pos.speed * 3.6).toFixed(1) + ' km/h' : '---');
+        setText('gpsVisPosHeading', pos.heading != null ? pos.heading.toFixed(1) + '\u00b0' : '---');
+        setText('gpsVisPosClimb', pos.climb != null ? pos.climb.toFixed(2) + ' m/s' : '---');
+
+        // Visuals: fix badge
+        const visFixEl = document.getElementById('gpsVisFixBadge');
+        if (visFixEl) {
+            const fq = pos.fix_quality;
+            if (fq === 3) { visFixEl.textContent = '3D FIX'; visFixEl.className = 'gps-fix-badge fix-3d'; }
+            else if (fq === 2) { visFixEl.textContent = '2D FIX'; visFixEl.className = 'gps-fix-badge fix-2d'; }
+            else { visFixEl.textContent = 'NO FIX'; visFixEl.className = 'gps-fix-badge no-fix'; }
+        }
+
+        // Visuals: GPS time
+        if (pos.timestamp) {
+            const t = new Date(pos.timestamp);
+            setText('gpsVisTime', t.toISOString().replace('T', ' ').replace(/\.\d+Z$/, ' UTC'));
+        }
+    }
+
+    function updateSkyUI(sky) {
+        // Sidebar sat counts
+        setText('gpsSatUsed', sky.usat != null ? sky.usat : '-');
+        setText('gpsSatTotal', sky.nsat != null ? sky.nsat : '-');
+
+        // DOP values
+        setDop('gpsHdop', sky.hdop);
+        setDop('gpsVdop', sky.vdop);
+        setDop('gpsPdop', sky.pdop);
+        setDop('gpsTdop', sky.tdop);
+        setDop('gpsGdop', sky.gdop);
+
+        // Visuals
+        drawSkyView(sky.satellites || []);
+        drawSignalBars(sky.satellites || []);
+    }
+
+    function setDop(id, val) {
+        const el = document.getElementById(id);
+        if (!el) return;
+        if (val == null) { el.textContent = '---'; el.className = 'gps-info-value gps-mono'; return; }
+        el.textContent = val.toFixed(1);
+        let cls = 'gps-info-value gps-mono ';
+        if (val <= 2) cls += 'gps-dop-good';
+        else if (val <= 5) cls += 'gps-dop-moderate';
+        else cls += 'gps-dop-poor';
+        el.className = cls;
+    }
+
+    function setText(id, val) {
+        const el = document.getElementById(id);
+        if (el) el.textContent = val;
+    }
+
+    // ========================
+    // Sky View Polar Plot
+    // ========================
+
+    function drawEmptySkyView() {
+        const canvas = document.getElementById('gpsSkyCanvas');
+        if (!canvas) return;
+        drawSkyViewBase(canvas);
+    }
+
+    function drawSkyView(satellites) {
+        const canvas = document.getElementById('gpsSkyCanvas');
+        if (!canvas) return;
+
+        const ctx = canvas.getContext('2d');
+        const w = canvas.width;
+        const h = canvas.height;
+        const cx = w / 2;
+        const cy = h / 2;
+        const r = Math.min(cx, cy) - 24;
+
+        drawSkyViewBase(canvas);
+
+        // Plot satellites
+        satellites.forEach(sat => {
+            if (sat.elevation == null || sat.azimuth == null) return;
+
+            const elRad = (90 - sat.elevation) / 90;
+            const azRad = (sat.azimuth - 90) * Math.PI / 180; // N = up
+            const px = cx + r * elRad * Math.cos(azRad);
+            const py = cy + r * elRad * Math.sin(azRad);
+
+            const color = CONST_COLORS[sat.constellation] || CONST_COLORS['GPS'];
+            const dotSize = sat.used ? 6 : 4;
+
+            // Draw dot
+            ctx.beginPath();
+            ctx.arc(px, py, dotSize, 0, Math.PI * 2);
+            if (sat.used) {
+                ctx.fillStyle = color;
+                ctx.fill();
+            } else {
+                ctx.strokeStyle = color;
+                ctx.lineWidth = 1.5;
+                ctx.stroke();
+            }
+
+            // PRN label
+            ctx.fillStyle = color;
+            ctx.font = '8px JetBrains Mono, monospace';
+            ctx.textAlign = 'center';
+            ctx.textBaseline = 'bottom';
+            ctx.fillText(sat.prn, px, py - dotSize - 2);
+
+            // SNR value
+            if (sat.snr != null) {
+                ctx.fillStyle = 'rgba(255,255,255,0.4)';
+                ctx.font = '7px JetBrains Mono, monospace';
+                ctx.textBaseline = 'top';
+                ctx.fillText(Math.round(sat.snr), px, py + dotSize + 1);
+            }
+        });
+    }
+
+    function drawSkyViewBase(canvas) {
+        const ctx = canvas.getContext('2d');
+        const w = canvas.width;
+        const h = canvas.height;
+        const cx = w / 2;
+        const cy = h / 2;
+        const r = Math.min(cx, cy) - 24;
+
+        ctx.clearRect(0, 0, w, h);
+
+        // Background
+        const bgStyle = getComputedStyle(document.documentElement).getPropertyValue('--bg-card').trim();
+        ctx.fillStyle = bgStyle || '#0d1117';
+        ctx.fillRect(0, 0, w, h);
+
+        // Elevation rings (0, 30, 60, 90)
+        ctx.strokeStyle = '#2a3040';
+        ctx.lineWidth = 0.5;
+        [90, 60, 30].forEach(el => {
+            const gr = r * (1 - el / 90);
+            ctx.beginPath();
+            ctx.arc(cx, cy, gr, 0, Math.PI * 2);
+            ctx.stroke();
+            // Label
+            ctx.fillStyle = '#555';
+            ctx.font = '9px JetBrains Mono, monospace';
+            ctx.textAlign = 'left';
+            ctx.textBaseline = 'middle';
+            ctx.fillText(el + '\u00b0', cx + gr + 3, cy - 2);
+        });
+
+        // Horizon circle
+        ctx.strokeStyle = '#3a4050';
+        ctx.lineWidth = 1;
+        ctx.beginPath();
+        ctx.arc(cx, cy, r, 0, Math.PI * 2);
+        ctx.stroke();
+
+        // Cardinal directions
+        ctx.fillStyle = '#888';
+        ctx.font = 'bold 11px JetBrains Mono, monospace';
+        ctx.textAlign = 'center';
+        ctx.textBaseline = 'middle';
+        ctx.fillText('N', cx, cy - r - 12);
+        ctx.fillText('S', cx, cy + r + 12);
+        ctx.fillText('E', cx + r + 12, cy);
+        ctx.fillText('W', cx - r - 12, cy);
+
+        // Crosshairs
+        ctx.strokeStyle = '#2a3040';
+        ctx.lineWidth = 0.5;
+        ctx.beginPath();
+        ctx.moveTo(cx, cy - r);
+        ctx.lineTo(cx, cy + r);
+        ctx.moveTo(cx - r, cy);
+        ctx.lineTo(cx + r, cy);
+        ctx.stroke();
+
+        // Zenith dot
+        ctx.fillStyle = '#333';
+        ctx.beginPath();
+        ctx.arc(cx, cy, 2, 0, Math.PI * 2);
+        ctx.fill();
+    }
+
+    // ========================
+    // Signal Strength Bars
+    // ========================
+
+    function drawSignalBars(satellites) {
+        const container = document.getElementById('gpsSignalBars');
+        if (!container) return;
+
+        container.innerHTML = '';
+
+        if (satellites.length === 0) return;
+
+        // Sort: used first, then by PRN
+        const sorted = [...satellites].sort((a, b) => {
+            if (a.used !== b.used) return a.used ? -1 : 1;
+            return a.prn - b.prn;
+        });
+
+        const maxSnr = 50; // dB-Hz typical max for display
+
+        sorted.forEach(sat => {
+            const snr = sat.snr || 0;
+            const heightPct = Math.min(snr / maxSnr * 100, 100);
+            const color = CONST_COLORS[sat.constellation] || CONST_COLORS['GPS'];
+            const constClass = 'gps-const-' + (sat.constellation || 'GPS').toLowerCase();
+
+            const wrap = document.createElement('div');
+            wrap.className = 'gps-signal-bar-wrap';
+
+            const snrLabel = document.createElement('span');
+            snrLabel.className = 'gps-signal-snr';
+            snrLabel.textContent = snr > 0 ? Math.round(snr) : '';
+
+            const bar = document.createElement('div');
+            bar.className = 'gps-signal-bar ' + constClass + (sat.used ? '' : ' unused');
+            bar.style.height = Math.max(heightPct, 2) + '%';
+            bar.title = `PRN ${sat.prn} (${sat.constellation}) - ${Math.round(snr)} dB-Hz${sat.used ? ' [USED]' : ''}`;
+
+            const prn = document.createElement('span');
+            prn.className = 'gps-signal-prn';
+            prn.textContent = sat.prn;
+
+            wrap.appendChild(snrLabel);
+            wrap.appendChild(bar);
+            wrap.appendChild(prn);
+            container.appendChild(wrap);
+        });
+    }
+
+    // ========================
+    // Cleanup
+    // ========================
+
+    function destroy() {
+        unsubscribeFromStream();
+    }
+
+    return {
+        init: init,
+        connect: connect,
+        disconnect: disconnect,
+        destroy: destroy,
+    };
+})();

templates/adsb_dashboard.html

@@ -3869,7 +3869,9 @@ sudo make install</code>
         }
 
         function startAcars() {
-            const device = document.getElementById('acarsDeviceSelect').value;
+            const acarsSelect = document.getElementById('acarsDeviceSelect');
+            const device = acarsSelect.value;
+            const sdr_type = acarsSelect.selectedOptions[0]?.dataset.sdrType || 'rtlsdr';
             const frequencies = getAcarsRegionFreqs();
 
             // Check if using agent mode
@@ -3895,7 +3897,7 @@ sudo make install</code>
             fetch(endpoint, {
                 method: 'POST',
                 headers: { 'Content-Type': 'application/json' },
-                body: JSON.stringify({ device, frequencies, gain: '40' })
+                body: JSON.stringify({ device, frequencies, gain: '40', sdr_type })
             })
             .then(r => r.json())
             .then(data => {
@@ -4101,6 +4103,7 @@ sudo make install</code>
                         devices.forEach((d, i) => {
                             const opt = document.createElement('option');
                             opt.value = d.index || i;
+                            opt.dataset.sdrType = d.sdr_type || 'rtlsdr';
                             opt.textContent = `SDR ${d.index || i}: ${d.name || d.type || 'SDR'}`;
                             select.appendChild(opt);
                         });
@@ -4880,6 +4883,7 @@ sudo make install</code>
                     devices.forEach(device => {
                         const opt = document.createElement('option');
                         opt.value = device.index;
+                        opt.dataset.sdrType = device.sdr_type || 'rtlsdr';
                         opt.textContent = `SDR ${device.index}: ${device.name || device.type || 'SDR'}`;
                         select.appendChild(opt);
                     });

templates/index.html

@@ -63,7 +63,9 @@
     <link rel="stylesheet" href="{{ url_for('static', filename='css/modes/sstv.css') }}">
     <link rel="stylesheet" href="{{ url_for('static', filename='css/modes/weather-satellite.css') }}">
     <link rel="stylesheet" href="{{ url_for('static', filename='css/modes/sstv-general.css') }}">
+    <link rel="stylesheet" href="{{ url_for('static', filename='css/modes/gps.css') }}">
     <link rel="stylesheet" href="{{ url_for('static', filename='css/modes/subghz.css') }}?v={{ version }}&r=subghz_layout9">
+    <link rel="stylesheet" href="{{ url_for('static', filename='css/modes/bt_locate.css') }}?v={{ version }}&r=btlocate2">
     <link rel="stylesheet" href="{{ url_for('static', filename='css/settings.css') }}">
     <link rel="stylesheet" href="{{ url_for('static', filename='css/components/function-strip.css') }}">
     <link rel="stylesheet" href="{{ url_for('static', filename='css/components/toast.css') }}">
@@ -214,6 +216,10 @@
                                 <span class="mode-icon icon"><svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><polyline points="6.5 6.5 17.5 17.5 12 22 12 2 17.5 6.5 6.5 17.5"/></svg></span>
                                 <span class="mode-name">Bluetooth</span>
                             </button>
+                            <button class="mode-card mode-card-sm" onclick="selectMode('bt_locate')">
+                                <span class="mode-icon icon"><svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><circle cx="12" cy="10" r="3"/><path d="M12 21.7C17.3 17 20 13 20 10a8 8 0 1 0-16 0c0 3 2.7 7 8 11.7z"/><path d="M9.5 8.5l3 3 2-4-2 4-3 3"/></svg></span>
+                                <span class="mode-name">BT Locate</span>
+                            </button>
                         </div>
                     </div>
 
@@ -248,6 +254,10 @@
                                 <span class="mode-icon icon"><svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><rect x="3" y="3" width="18" height="18" rx="2"/><circle cx="12" cy="12" r="3"/><path d="M16.24 7.76a6 6 0 0 1 0 8.49m-8.48-.01a6 6 0 0 1 0-8.49"/></svg></span>
                                 <span class="mode-name">HF SSTV</span>
                             </button>
+                            <button class="mode-card mode-card-sm" onclick="selectMode('gps')">
+                                <span class="mode-icon icon"><svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><circle cx="12" cy="10" r="3"/><path d="M12 21.7C17.3 17 20 13 20 10a8 8 0 1 0-16 0c0 3 2.7 7 8 11.7z"/></svg></span>
+                                <span class="mode-name">GPS</span>
+                            </button>
                         </div>
                     </div>
                 </div>
@@ -433,6 +443,7 @@
                         <label style="font-size: 11px; color: #888; margin-bottom: 4px;">Hardware Type</label>
                         <select id="sdrTypeSelect" onchange="onSDRTypeChanged()">
                             <option value="rtlsdr">RTL-SDR</option>
+                            <option value="sdrplay">SDRplay</option>
                             <option value="limesdr">LimeSDR</option>
                             <option value="hackrf">HackRF</option>
                             <option value="airspy">Airspy</option>
@@ -538,6 +549,8 @@
 
                 {% include 'partials/modes/sstv-general.html' %}
 
+                {% include 'partials/modes/gps.html' %}
+
                 {% include 'partials/modes/listening-post.html' %}
 
                 {% include 'partials/modes/tscm.html' %}
@@ -554,6 +567,8 @@
 
                 {% include 'partials/modes/subghz.html' %}
 
+                {% include 'partials/modes/bt_locate.html' %}
+
                 <button class="preset-btn" onclick="killAll()"
                     style="width: 100%; margin-top: 10px; border-color: #ff3366; color: #ff3366;">
                     Kill All Processes
@@ -780,7 +795,10 @@
                                     <div class="bt-detail-top-row">
                                         <div class="bt-detail-identity">
                                             <div class="bt-detail-name" id="btDetailName">Device Name</div>
-                                            <div class="bt-detail-address" id="btDetailAddress">00:00:00:00:00:00</div>
+                                            <div class="bt-detail-address">
+                                                <span id="btDetailAddress">00:00:00:00:00:00</span>
+                                                <span class="bt-mac-cluster-badge" id="btDetailMacCluster" style="display:none;"></span>
+                                            </div>
                                         </div>
                                         <div class="bt-detail-rssi-display">
                                             <span class="bt-detail-rssi-value" id="btDetailRssi">--</span>
@@ -821,13 +839,42 @@
                                             <span class="bt-detail-stat-label">Mfr ID</span>
                                             <span class="bt-detail-stat-value" id="btDetailMfrId">--</span>
                                         </div>
+                                        <div class="bt-detail-stat">
+                                            <span class="bt-detail-stat-label">TX Power</span>
+                                            <span class="bt-detail-stat-value" id="btDetailTxPower">--</span>
+                                        </div>
+                                        <div class="bt-detail-stat">
+                                            <span class="bt-detail-stat-label">Seen Rate</span>
+                                            <span class="bt-detail-stat-value" id="btDetailSeenRate">--</span>
+                                        </div>
+                                        <div class="bt-detail-stat">
+                                            <span class="bt-detail-stat-label">Stability</span>
+                                            <span class="bt-detail-stat-value" id="btDetailStability">--</span>
+                                        </div>
+                                        <div class="bt-detail-stat">
+                                            <span class="bt-detail-stat-label">Distance</span>
+                                            <span class="bt-detail-stat-value" id="btDetailDistance">--</span>
+                                        </div>
+                                    </div>
+                                    <!-- Service Data Inspector (collapsible) -->
+                                    <div class="bt-detail-service-inspector" id="btDetailServiceInspector" style="display:none;">
+                                        <div class="bt-inspector-toggle" onclick="BluetoothMode.toggleServiceInspector()">
+                                            <span class="bt-inspector-arrow" id="btInspectorArrow">&#9656;</span> Raw Data
+                                        </div>
+                                        <div class="bt-inspector-content" id="btInspectorContent" style="display:none;">
+                                        </div>
                                     </div>
                                     <div class="bt-detail-bottom-row">
+                                        <div class="bt-detail-irk" id="btDetailIrk" style="display: none;">
+                                            <span class="bt-irk-badge">IRK</span>
+                                            <span class="bt-detail-irk-value" id="btDetailIrkValue" style="font-size:10px;color:var(--text-dim);font-family:var(--font-mono);margin-left:6px;word-break:break-all;"></span>
+                                        </div>
                                         <div class="bt-detail-services" id="btDetailServices" style="display: none;">
                                             <span class="bt-detail-services-list" id="btDetailServicesList"></span>
                                         </div>
                                         <button class="bt-detail-btn" id="btDetailWatchBtn" onclick="BluetoothMode.toggleWatchlist()">Watchlist</button>
                                         <button class="bt-detail-btn" id="btDetailCopyBtn" onclick="BluetoothMode.copyAddress()">Copy</button>
+                                        <button class="bt-detail-btn bt-locate-btn" id="btDetailLocateBtn" onclick="BluetoothMode.locateDevice()">Locate</button>
                                     </div>
                                 </div>
                             </div>
@@ -1043,6 +1090,67 @@
                     </div>
                 </div>
 
+                <!-- GPS Receiver Dashboard -->
+                <div id="gpsVisuals" class="gps-visuals-container" style="display: none;">
+                    <div class="gps-visuals-top">
+                        <!-- Sky View Polar Plot -->
+                        <div class="gps-skyview-panel">
+                            <h4>Satellite Sky View</h4>
+                            <div class="gps-skyview-canvas-wrap">
+                                <canvas id="gpsSkyCanvas" width="400" height="400"></canvas>
+                            </div>
+                            <div class="gps-legend">
+                                <div class="gps-legend-item"><span class="gps-legend-dot" style="background:#00d4ff;"></span> GPS</div>
+                                <div class="gps-legend-item"><span class="gps-legend-dot" style="background:#00ff88;"></span> GLONASS</div>
+                                <div class="gps-legend-item"><span class="gps-legend-dot" style="background:#ff8800;"></span> Galileo</div>
+                                <div class="gps-legend-item"><span class="gps-legend-dot" style="background:#ff4466;"></span> BeiDou</div>
+                                <div class="gps-legend-item"><span class="gps-legend-dot" style="background:#ffdd00;"></span> SBAS</div>
+                                <div class="gps-legend-item"><span class="gps-legend-dot" style="background:#cc66ff;"></span> QZSS</div>
+                                <div class="gps-legend-item"><span class="gps-legend-dot" style="background:#00d4ff;"></span> Used (filled)</div>
+                                <div class="gps-legend-item"><span class="gps-legend-dot" style="background:transparent; border:1.5px solid #00d4ff;"></span> Unused (hollow)</div>
+                            </div>
+                        </div>
+                        <!-- Position Info -->
+                        <div class="gps-position-panel">
+                            <h4>Position</h4>
+                            <div class="gps-pos-big">
+                                <div id="gpsVisPosLat">---</div>
+                                <div id="gpsVisPosLon">---</div>
+                            </div>
+                            <div style="margin-top: 4px;">
+                                <span class="gps-fix-badge no-fix" id="gpsVisFixBadge">NO FIX</span>
+                            </div>
+                            <div style="margin-top: 12px;">
+                                <div class="gps-pos-row">
+                                    <span class="gps-pos-label">Altitude</span>
+                                    <span class="gps-pos-value" id="gpsVisPosAlt">---</span>
+                                </div>
+                                <div class="gps-pos-row">
+                                    <span class="gps-pos-label">Speed</span>
+                                    <span class="gps-pos-value" id="gpsVisPosSpeed">---</span>
+                                </div>
+                                <div class="gps-pos-row">
+                                    <span class="gps-pos-label">Heading</span>
+                                    <span class="gps-pos-value" id="gpsVisPosHeading">---</span>
+                                </div>
+                                <div class="gps-pos-row">
+                                    <span class="gps-pos-label">Climb</span>
+                                    <span class="gps-pos-value" id="gpsVisPosClimb">---</span>
+                                </div>
+                            </div>
+                            <div style="margin-top: auto; padding-top: 12px; border-top: 1px solid var(--border-color);">
+                                <div class="gps-pos-label">GPS TIME</div>
+                                <div class="gps-pos-value" id="gpsVisTime" style="font-size: 14px; color: var(--accent-cyan);">---</div>
+                            </div>
+                        </div>
+                    </div>
+                    <!-- Signal Strength Bars -->
+                    <div class="gps-signal-panel">
+                        <h4>Signal Strength (SNR dB-Hz)</h4>
+                        <div class="gps-signal-bars" id="gpsSignalBars"></div>
+                    </div>
+                </div>
+
                 <!-- Listening Post Visualizations - Professional Ham Radio Scanner -->
                 <div class="wifi-visuals" id="listeningPostVisuals" style="display: none;">
 
@@ -2064,6 +2172,75 @@
 
                 </div>
 
+                <!-- BT Locate SAR Dashboard -->
+                <div id="btLocateVisuals" class="btl-visuals-container" style="display: none;">
+                    <!-- Proximity HUD -->
+                    <div class="btl-hud" id="btLocateHud" style="display: none;">
+                        <div class="btl-hud-top">
+                            <div class="btl-hud-band" id="btLocateBand">---</div>
+                            <div class="btl-hud-metrics">
+                                <div class="btl-hud-metric btl-hud-metric-lg">
+                                    <span class="btl-hud-value" id="btLocateDistance">--</span>
+                                    <span class="btl-hud-unit">m</span>
+                                    <span class="btl-hud-label">Est. Distance</span>
+                                </div>
+                                <div class="btl-hud-metric">
+                                    <span class="btl-hud-value" id="btLocateRssi">--</span>
+                                    <span class="btl-hud-unit">dBm</span>
+                                    <span class="btl-hud-label">RSSI</span>
+                                </div>
+                                <div class="btl-hud-metric">
+                                    <span class="btl-hud-value" id="btLocateRssiEma">--</span>
+                                    <span class="btl-hud-unit">dBm</span>
+                                    <span class="btl-hud-label">RSSI avg</span>
+                                </div>
+                                <div class="btl-hud-separator"></div>
+                                <div class="btl-hud-metric">
+                                    <span class="btl-hud-value" id="btLocateDetectionCount">0</span>
+                                    <span class="btl-hud-unit">&nbsp;</span>
+                                    <span class="btl-hud-label">Detections</span>
+                                </div>
+                                <div class="btl-hud-metric">
+                                    <span class="btl-hud-value" id="btLocateGpsCount">0</span>
+                                    <span class="btl-hud-unit">&nbsp;</span>
+                                    <span class="btl-hud-label">GPS pts</span>
+                                </div>
+                                <div class="btl-hud-metric">
+                                    <span class="btl-hud-value" id="btLocateSessionTime">0:00</span>
+                                    <span class="btl-hud-unit">&nbsp;</span>
+                                    <span class="btl-hud-label">Duration</span>
+                                </div>
+                            </div>
+                            <div class="btl-hud-controls">
+                                <label class="btl-hud-audio-toggle">
+                                    <input type="checkbox" id="btLocateAudioEnable" onchange="BtLocate.toggleAudio()">
+                                    <span>Audio</span>
+                                </label>
+                                <button class="btl-hud-clear-btn" onclick="BtLocate.clearTrail()">Clear Trail</button>
+                            </div>
+                        </div>
+                        <div class="btl-hud-bottom">
+                            <div class="btl-hud-info">
+                                <span class="btl-hud-info-item" id="btLocateTargetInfo">--</span>
+                                <span class="btl-hud-info-sep">&middot;</span>
+                                <span class="btl-hud-info-item" id="btLocateEnvInfo">--</span>
+                                <span class="btl-hud-info-sep">&middot;</span>
+                                <span class="btl-hud-info-item" id="btLocateGpsStatus">GPS: --</span>
+                                <span class="btl-hud-info-sep">&middot;</span>
+                                <span class="btl-hud-info-item" id="btLocateLastSeen">Last: --</span>
+                            </div>
+                            <div id="btLocateDiag" class="btl-hud-diag"></div>
+                        </div>
+                    </div>
+                    <div class="btl-map-container">
+                        <div id="btLocateMap"></div>
+                    </div>
+                    <div class="btl-rssi-chart-container">
+                        <span class="btl-chart-label">RSSI History</span>
+                        <canvas id="btLocateRssiChart"></canvas>
+                    </div>
+                </div>
+
                 <!-- WebSDR Dashboard -->
                 <div id="websdrVisuals" style="display: none; padding: 12px; flex-direction: column; gap: 12px; flex: 1; min-height: 0; overflow: hidden;">
                     <!-- Audio Control Bar (hidden until connected) -->
@@ -2831,7 +3008,7 @@
     <script src="{{ url_for('static', filename='js/components/device-card.js') }}"></script>
     <script src="{{ url_for('static', filename='js/components/proximity-radar.js') }}"></script>
     <script src="{{ url_for('static', filename='js/components/timeline-heatmap.js') }}"></script>
-    <script src="{{ url_for('static', filename='js/modes/bluetooth.js') }}"></script>
+    <script src="{{ url_for('static', filename='js/modes/bluetooth.js') }}?v={{ version }}&r=btlocate1"></script>
     <!-- WiFi v2 components -->
     <script src="{{ url_for('static', filename='js/components/channel-chart.js') }}"></script>
     <script src="{{ url_for('static', filename='js/modes/wifi.js') }}"></script>
@@ -2841,9 +3018,11 @@
     <script src="{{ url_for('static', filename='js/modes/sstv.js') }}"></script>
     <script src="{{ url_for('static', filename='js/modes/weather-satellite.js') }}"></script>
     <script src="{{ url_for('static', filename='js/modes/sstv-general.js') }}"></script>
+    <script src="{{ url_for('static', filename='js/modes/gps.js') }}"></script>
     <script src="{{ url_for('static', filename='js/modes/dmr.js') }}"></script>
     <script src="{{ url_for('static', filename='js/modes/websdr.js') }}"></script>
     <script src="{{ url_for('static', filename='js/modes/subghz.js') }}?v={{ version }}&r=subghz_layout9"></script>
+    <script src="{{ url_for('static', filename='js/modes/bt_locate.js') }}?v={{ version }}&r=btlocate2"></script>
 
     <script>
         // ============================================
@@ -2978,8 +3157,8 @@
         let pendingStartMode = null;
         const validModes = new Set([
             'pager', 'sensor', 'rtlamr', 'aprs', 'listening',
-            'spystations', 'meshtastic', 'wifi', 'bluetooth',
+            'spystations', 'meshtastic', 'wifi', 'bluetooth', 'bt_locate',
-            'tscm', 'satellite', 'sstv', 'weathersat', 'sstv_general', 'websdr', 'subghz'
+            'tscm', 'satellite', 'sstv', 'weathersat', 'sstv_general', 'gps', 'websdr', 'subghz'
         ]);
 
         function getModeFromQuery() {
@@ -3435,11 +3614,11 @@
             const modeGroups = {
                 'pager': 'sdr', 'sensor': 'sdr',
                 'aprs': 'sdr', 'listening': 'sdr',
-                'wifi': 'wireless', 'bluetooth': 'wireless',
+                'wifi': 'wireless', 'bluetooth': 'wireless', 'bt_locate': 'wireless',
                 'tscm': 'security',
                 'rtlamr': 'sdr', 'ais': 'sdr', 'spystations': 'sdr',
                 'meshtastic': 'sdr',
-                'satellite': 'space', 'sstv': 'space', 'weathersat': 'space', 'sstv_general': 'space',
+                'satellite': 'space', 'sstv': 'space', 'weathersat': 'space', 'sstv_general': 'space', 'gps': 'space',
                 'subghz': 'sdr'
             };
 
@@ -3513,7 +3692,7 @@
             document.querySelectorAll('.mode-nav-btn').forEach(btn => btn.classList.remove('active'));
             const modeMap = {
                 'pager': 'pager', 'sensor': '433',
-                'satellite': 'satellite', 'wifi': 'wifi', 'bluetooth': 'bluetooth',
+                'satellite': 'satellite', 'wifi': 'wifi', 'bluetooth': 'bluetooth', 'bt_locate': 'bt locate',
                 'listening': 'listening', 'aprs': 'aprs', 'tscm': 'tscm', 'meshtastic': 'meshtastic',
                 'dmr': 'dmr', 'websdr': 'websdr', 'sstv_general': 'hf sstv'
             };
@@ -3530,8 +3709,10 @@
             document.getElementById('sstvMode')?.classList.toggle('active', mode === 'sstv');
             document.getElementById('weatherSatMode')?.classList.toggle('active', mode === 'weathersat');
             document.getElementById('sstvGeneralMode')?.classList.toggle('active', mode === 'sstv_general');
+            document.getElementById('gpsMode')?.classList.toggle('active', mode === 'gps');
             document.getElementById('wifiMode')?.classList.toggle('active', mode === 'wifi');
             document.getElementById('bluetoothMode')?.classList.toggle('active', mode === 'bluetooth');
+            document.getElementById('btLocateMode')?.classList.toggle('active', mode === 'bt_locate');
             document.getElementById('listeningPostMode')?.classList.toggle('active', mode === 'listening');
             document.getElementById('aprsMode')?.classList.toggle('active', mode === 'aprs');
             document.getElementById('tscmMode')?.classList.toggle('active', mode === 'tscm');
@@ -3569,8 +3750,10 @@
                 'sstv': 'ISS SSTV',
                 'weathersat': 'WEATHER SAT',
                 'sstv_general': 'HF SSTV',
+                'gps': 'GPS',
                 'wifi': 'WIFI',
                 'bluetooth': 'BLUETOOTH',
+                'bt_locate': 'BT LOCATE',
                 'listening': 'LISTENING POST',
                 'aprs': 'APRS',
                 'tscm': 'TSCM',
@@ -3594,9 +3777,11 @@
             const sstvVisuals = document.getElementById('sstvVisuals');
             const weatherSatVisuals = document.getElementById('weatherSatVisuals');
             const sstvGeneralVisuals = document.getElementById('sstvGeneralVisuals');
+            const gpsVisuals = document.getElementById('gpsVisuals');
             const dmrVisuals = document.getElementById('dmrVisuals');
             const websdrVisuals = document.getElementById('websdrVisuals');
             const subghzVisuals = document.getElementById('subghzVisuals');
+            const btLocateVisuals = document.getElementById('btLocateVisuals');
             if (wifiLayoutContainer) wifiLayoutContainer.style.display = mode === 'wifi' ? 'flex' : 'none';
             if (btLayoutContainer) btLayoutContainer.style.display = mode === 'bluetooth' ? 'flex' : 'none';
             if (satelliteVisuals) satelliteVisuals.style.display = mode === 'satellite' ? 'block' : 'none';
@@ -3608,9 +3793,11 @@
             if (sstvVisuals) sstvVisuals.style.display = mode === 'sstv' ? 'flex' : 'none';
             if (weatherSatVisuals) weatherSatVisuals.style.display = mode === 'weathersat' ? 'flex' : 'none';
             if (sstvGeneralVisuals) sstvGeneralVisuals.style.display = mode === 'sstv_general' ? 'flex' : 'none';
+            if (gpsVisuals) gpsVisuals.style.display = mode === 'gps' ? 'flex' : 'none';
             if (dmrVisuals) dmrVisuals.style.display = mode === 'dmr' ? 'flex' : 'none';
             if (websdrVisuals) websdrVisuals.style.display = mode === 'websdr' ? 'flex' : 'none';
             if (subghzVisuals) subghzVisuals.style.display = mode === 'subghz' ? 'flex' : 'none';
+            if (btLocateVisuals) btLocateVisuals.style.display = mode === 'bt_locate' ? 'flex' : 'none';
 
             // Hide sidebar by default for Meshtastic mode, show for others
             const mainContent = document.querySelector('.main-content');
@@ -3637,8 +3824,10 @@
                 'sstv': 'ISS SSTV Decoder',
                 'weathersat': 'Weather Satellite Decoder',
                 'sstv_general': 'HF SSTV Decoder',
+                'gps': 'GPS Receiver',
                 'wifi': 'WiFi Scanner',
                 'bluetooth': 'Bluetooth Scanner',
+                'bt_locate': 'BT Locate — SAR Tracker',
                 'listening': 'Listening Post',
                 'aprs': 'APRS Tracker',
                 'tscm': 'TSCM Counter-Surveillance',
@@ -3665,7 +3854,7 @@
             const reconBtn = document.getElementById('reconBtn');
             const intelBtn = document.querySelector('[onclick="exportDeviceDB()"]');
             const reconPanel = document.getElementById('reconPanel');
-            if (mode === 'satellite' || mode === 'sstv' || mode === 'weathersat' || mode === 'sstv_general' || mode === 'listening' || mode === 'aprs' || mode === 'tscm' || mode === 'spystations' || mode === 'meshtastic' || mode === 'dmr' || mode === 'websdr' || mode === 'subghz') {
+            if (mode === 'satellite' || mode === 'sstv' || mode === 'weathersat' || mode === 'sstv_general' || mode === 'gps' || mode === 'listening' || mode === 'aprs' || mode === 'tscm' || mode === 'spystations' || mode === 'meshtastic' || mode === 'dmr' || mode === 'websdr' || mode === 'subghz') {
                 if (reconPanel) reconPanel.style.display = 'none';
                 if (reconBtn) reconBtn.style.display = 'none';
                 if (intelBtn) intelBtn.style.display = 'none';
@@ -3758,6 +3947,8 @@
                 }, 100);
             } else if (mode === 'sstv_general') {
                 SSTVGeneral.init();
+            } else if (mode === 'gps') {
+                GPS.init();
             } else if (mode === 'dmr') {
                 if (typeof checkDmrTools === 'function') checkDmrTools();
                 if (typeof checkDmrStatus === 'function') checkDmrStatus();
@@ -3766,6 +3957,8 @@
                 if (typeof initWebSDR === 'function') initWebSDR();
             } else if (mode === 'subghz') {
                 SubGhz.init();
+            } else if (mode === 'bt_locate') {
+                BtLocate.init();
             }
         }
 
@@ -3773,6 +3966,7 @@
         window.addEventListener('resize', function () {
             if (aprsMap) aprsMap.invalidateSize();
             if (typeof Meshtastic !== 'undefined') Meshtastic.invalidateMap();
+            if (typeof BtLocate !== 'undefined') BtLocate.invalidateMap();
         });
 
         window.addEventListener('popstate', function () {
@@ -4784,8 +4978,10 @@
         // SDR hardware capabilities
         const sdrCapabilities = {
             'rtlsdr': { name: 'RTL-SDR', freq_min: 24, freq_max: 1766, gain_min: 0, gain_max: 50 },
+            'sdrplay': { name: 'SDRplay', freq_min: 0.001, freq_max: 2000, gain_min: 0, gain_max: 59 },
             'limesdr': { name: 'LimeSDR', freq_min: 0.1, freq_max: 3800, gain_min: 0, gain_max: 73 },
-            'hackrf': { name: 'HackRF', freq_min: 1, freq_max: 6000, gain_min: 0, gain_max: 62 }
+            'hackrf': { name: 'HackRF', freq_min: 1, freq_max: 6000, gain_min: 0, gain_max: 62 },
+            'airspy': { name: 'Airspy', freq_min: 24, freq_max: 1800, gain_min: 0, gain_max: 21 }
         };
 
         // Current device list with SDR type info
@@ -10012,6 +10208,20 @@
 
         let gpsReconnectTimeout = null;
 
+        // GPS subscriber callbacks - modules can register to receive GPS stream data
+        const gpsStreamSubscribers = [];
+
+        function addGpsStreamSubscriber(fn) {
+            if (!gpsStreamSubscribers.includes(fn)) {
+                gpsStreamSubscribers.push(fn);
+            }
+        }
+
+        function removeGpsStreamSubscriber(fn) {
+            const idx = gpsStreamSubscribers.indexOf(fn);
+            if (idx !== -1) gpsStreamSubscribers.splice(idx, 1);
+        }
+
         function startGpsStream() {
             if (gpsEventSource) {
                 gpsEventSource.close();
@@ -10029,6 +10239,8 @@
                         gpsLastPosition = data;
                         updateLocationFromGps(data);
                     }
+                    // Dispatch to all subscribers (e.g. GPS mode UI)
+                    gpsStreamSubscribers.forEach(fn => fn(data));
                 } catch (e) {
                     console.error('GPS parse error:', e);
                 }
@@ -10621,10 +10833,7 @@
         }
 
         // Satellite management
-        let trackedSatellites = [
+        let trackedSatellites = [];
-            { id: 'ISS', name: 'ISS (ZARYA)', norad: '25544', builtin: true, checked: true },
-            { id: 'METEOR-M2', name: 'Meteor-M 2', norad: '40069', builtin: true, checked: true }
-        ];
 
         function renderSatelliteList() {
             const list = document.getElementById('satTrackingList');
@@ -10643,14 +10852,27 @@
         }
 
         function toggleSatellite(idx) {
-            trackedSatellites[idx].checked = !trackedSatellites[idx].checked;
+            const sat = trackedSatellites[idx];
+            sat.checked = !sat.checked;
+            fetch(`/satellite/tracked/${sat.norad}`, {
+                method: 'PUT',
+                headers: { 'Content-Type': 'application/json' },
+                body: JSON.stringify({ enabled: sat.checked })
+            }).catch(() => {});
         }
 
         function removeSatellite(idx) {
-            if (!trackedSatellites[idx].builtin) {
+            const sat = trackedSatellites[idx];
-                trackedSatellites.splice(idx, 1);
+            if (sat.builtin) return;
-                renderSatelliteList();
+            fetch(`/satellite/tracked/${sat.norad}`, { method: 'DELETE' })
-            }
+                .then(r => r.json())
+                .then(data => {
+                    if (data.status === 'success') {
+                        trackedSatellites.splice(idx, 1);
+                        renderSatelliteList();
+                    }
+                })
+                .catch(() => {});
         }
 
         function getSelectedSatellites() {
@@ -10686,7 +10908,7 @@
             }
 
             const lines = tleText.split('\\n').map(l => l.trim()).filter(l => l);
-            let added = 0;
+            const toAdd = [];
 
             for (let i = 0; i < lines.length; i += 3) {
                 if (i + 2 < lines.length) {
@@ -10696,32 +10918,33 @@
 
                     if (line1.startsWith('1 ') && line2.startsWith('2 ')) {
                         const norad = line1.substring(2, 7).trim();
-                        const id = name.replace(/[^a-zA-Z0-9]/g, '-').toUpperCase();
-
-                        // Check if already exists
                         if (!trackedSatellites.find(s => s.norad === norad)) {
-                            trackedSatellites.push({
+                            toAdd.push({ norad_id: norad, name: name, tle1: line1, tle2: line2, enabled: true });
-                                id: id,
-                                name: name,
-                                norad: norad,
-                                builtin: false,
-                                checked: true,
-                                tle: [name, line1, line2]
-                            });
-                            added++;
                         }
                     }
                 }
             }
 
-            if (added > 0) {
+            if (toAdd.length === 0) {
-                renderSatelliteList();
-                document.getElementById('tleInput').value = '';
-                closeSatModal();
-                showInfo(`Added ${added} satellite(s)`);
-            } else {
                 alert('No valid TLE data found. Format: Name, Line 1, Line 2 (3 lines per satellite)');
+                return;
             }
+
+            fetch('/satellite/tracked', {
+                method: 'POST',
+                headers: { 'Content-Type': 'application/json' },
+                body: JSON.stringify(toAdd)
+            })
+            .then(r => r.json())
+            .then(data => {
+                if (data.status === 'success') {
+                    _loadSatellitesFromAPI();
+                    document.getElementById('tleInput').value = '';
+                    closeSatModal();
+                    showInfo(`Added ${data.added} satellite(s)`);
+                }
+            })
+            .catch(() => alert('Failed to save satellites'));
         }
 
         function fetchCelestrak() {
@@ -10737,35 +10960,76 @@
                 .then(r => r.json())
                 .then(data => {
                     if (data.status === 'success' && data.satellites) {
-                        let added = 0;
+                        const toAdd = data.satellites
-                        data.satellites.forEach(sat => {
+                            .filter(sat => !trackedSatellites.find(s => s.norad === String(sat.norad)))
-                            const noradStr = String(sat.norad);
+                            .map(sat => ({
-                            if (!trackedSatellites.find(s => s.norad === noradStr)) {
+                                norad_id: String(sat.norad),
-                                trackedSatellites.push({
+                                name: sat.name,
-                                    id: sat.name.replace(/[^a-zA-Z0-9-]/g, '-'),
+                                tle1: sat.tle1,
-                                    name: sat.name,
+                                tle2: sat.tle2,
-                                    norad: noradStr,
+                                enabled: false
-                                    builtin: false,
+                            }));
-                                    checked: false, // Don't auto-select
+
-                                    tle: [sat.name, sat.tle1, sat.tle2]
+                        if (toAdd.length === 0) {
-                                });
+                            status.innerHTML = `<span style="color: var(--accent-green);">All ${data.satellites.length} satellites already tracked</span>`;
-                                added++;
+                            return;
+                        }
+
+                        fetch('/satellite/tracked', {
+                            method: 'POST',
+                            headers: { 'Content-Type': 'application/json' },
+                            body: JSON.stringify(toAdd)
+                        })
+                        .then(r => r.json())
+                        .then(result => {
+                            if (result.status === 'success') {
+                                _loadSatellitesFromAPI();
+                                status.innerHTML = `<span style="color: var(--accent-green);">Added ${result.added} satellites (${data.satellites.length} total in category)</span>`;
                             }
+                        })
+                        .catch(() => {
+                            status.innerHTML = `<span style="color: var(--accent-red);">Failed to save satellites</span>`;
                         });
-                        renderSatelliteList();
-                        status.innerHTML = `<span style="color: var(--accent-green);">Added ${added} satellites (${data.satellites.length} total in category)</span>`;
                     } else {
                         status.innerHTML = `<span style="color: var(--accent-red);">Error: ${data.message || 'Failed to fetch'}</span>`;
                     }
                 })
-                .catch(err => {
+                .catch(() => {
                     status.innerHTML = `<span style="color: var(--accent-red);">Network error</span>`;
                 });
         }
 
+        function _loadSatellitesFromAPI() {
+            fetch('/satellite/tracked')
+                .then(r => r.json())
+                .then(data => {
+                    if (data.status === 'success' && data.satellites) {
+                        trackedSatellites = data.satellites.map(sat => ({
+                            id: sat.name.replace(/[^a-zA-Z0-9]/g, '-').toUpperCase(),
+                            name: sat.name,
+                            norad: sat.norad_id,
+                            builtin: sat.builtin,
+                            checked: sat.enabled,
+                            tle: sat.tle_line1 ? [sat.name, sat.tle_line1, sat.tle_line2] : null
+                        }));
+                        renderSatelliteList();
+                    }
+                })
+                .catch(() => {
+                    // Fallback to hardcoded defaults if API fails
+                    if (trackedSatellites.length === 0) {
+                        trackedSatellites = [
+                            { id: 'ISS', name: 'ISS (ZARYA)', norad: '25544', builtin: true, checked: true },
+                            { id: 'METEOR-M2', name: 'Meteor-M 2', norad: '40069', builtin: true, checked: true }
+                        ];
+                        renderSatelliteList();
+                    }
+                });
+        }
+
         // Initialize satellite list when satellite mode is loaded
         function initSatelliteList() {
-            renderSatelliteList();
+            _loadSatellitesFromAPI();
         }
 
         // Utility function

templates/partials/modes/bluetooth.html

@@ -26,6 +26,7 @@
                                 <option value="bleak">Bleak Library</option>
                                 <option value="hcitool">hcitool (Linux)</option>
                                 <option value="bluetoothctl">bluetoothctl (Linux)</option>
+                                <option value="ubertooth" id="btScanModeUbertooth" style="display:none;">Ubertooth One</option>
                             </select>
                         </div>
                         <div class="form-group">

templates/partials/modes/bt_locate.html

@@ -0,0 +1,72 @@
+<!-- BT LOCATE MODE -->
+<div id="btLocateMode" class="mode-content">
+    <div class="section">
+        <h3>BT Locate</h3>
+        <p class="info-text" style="font-size: 11px; color: var(--text-dim); margin-bottom: 12px;">
+            SAR Bluetooth device location &mdash; GPS-tagged signal trail mapping with proximity alerts for locating missing persons' devices.
+        </p>
+    </div>
+
+    <!-- Target Lock -->
+    <div class="section">
+        <h3>Target</h3>
+        <div id="btLocateHandoffCard" style="display: none; background: rgba(0,255,136,0.08); border: 1px solid rgba(0,255,136,0.3); border-radius: 6px; padding: 8px; margin-bottom: 8px;">
+            <div style="display: flex; justify-content: space-between; align-items: center;">
+                <span style="font-size: 10px; color: var(--accent-green); text-transform: uppercase; font-weight: 600;">Handed off from BT</span>
+                <button onclick="BtLocate.clearHandoff()" style="background: none; border: none; color: var(--text-dim); cursor: pointer; font-size: 10px;">&times;</button>
+            </div>
+            <div id="btLocateHandoffName" style="font-size: 12px; font-weight: 600; color: var(--text-primary); margin-top: 4px;"></div>
+            <div id="btLocateHandoffMeta" style="font-size: 10px; color: var(--text-dim); font-family: var(--font-mono);"></div>
+        </div>
+
+        <label class="input-label">MAC Address</label>
+        <input type="text" id="btLocateMac" class="text-input" placeholder="AA:BB:CC:DD:EE:FF" style="font-family: var(--font-mono); font-size: 11px;">
+
+        <label class="input-label" style="margin-top: 6px;">Name Pattern</label>
+        <input type="text" id="btLocateNamePattern" class="text-input" placeholder="iPhone, Galaxy, etc.">
+
+        <label class="input-label" style="margin-top: 6px;">IRK (hex, optional)</label>
+        <div style="display: flex; gap: 4px; align-items: center;">
+            <input type="text" id="btLocateIrk" class="text-input" placeholder="32 hex chars for RPA resolution" style="font-family: var(--font-mono); font-size: 10px; flex: 1;">
+            <button class="btl-detect-irk-btn" id="btLocateDetectIrkBtn" onclick="BtLocate.fetchPairedIrks()" title="Detect IRKs from paired devices">Detect</button>
+        </div>
+        <div id="btLocateIrkPicker" class="btl-irk-picker" style="display: none;">
+            <div id="btLocateIrkPickerStatus" class="btl-irk-picker-status"></div>
+            <div id="btLocateIrkPickerList" class="btl-irk-picker-list"></div>
+        </div>
+    </div>
+
+    <!-- Environment Preset -->
+    <div class="section">
+        <h3>Environment</h3>
+        <div class="btl-env-grid">
+            <button class="btl-env-btn" data-env="FREE_SPACE" onclick="BtLocate.setEnvironment('FREE_SPACE')">
+                <span class="btl-env-icon">&#127968;</span>
+                <span class="btl-env-label">Open Field</span>
+                <span class="btl-env-n">n=2.0</span>
+            </button>
+            <button class="btl-env-btn active" data-env="OUTDOOR" onclick="BtLocate.setEnvironment('OUTDOOR')">
+                <span class="btl-env-icon">&#127795;</span>
+                <span class="btl-env-label">Outdoor</span>
+                <span class="btl-env-n">n=2.2</span>
+            </button>
+            <button class="btl-env-btn" data-env="INDOOR" onclick="BtLocate.setEnvironment('INDOOR')">
+                <span class="btl-env-icon">&#127970;</span>
+                <span class="btl-env-label">Indoor</span>
+                <span class="btl-env-n">n=3.0</span>
+            </button>
+        </div>
+    </div>
+
+    <!-- Controls -->
+    <div class="section">
+        <div style="display: flex; gap: 6px;">
+            <button class="run-btn" id="btLocateStartBtn" onclick="BtLocate.start()">Start Locate</button>
+            <button class="stop-btn" id="btLocateStopBtn" onclick="BtLocate.stop()" style="display: none;">Stop</button>
+        </div>
+        <div id="btLocateScanStatus" style="display: none; margin-top: 6px; font-size: 10px; color: var(--text-dim);">
+            <span id="btLocateScanDot" style="display: inline-block; width: 6px; height: 6px; border-radius: 50%; background: #22c55e; margin-right: 4px; vertical-align: middle;"></span>
+            <span id="btLocateScanText">BT scanner active</span>
+        </div>
+    </div>
+</div>

templates/partials/modes/gps.html

@@ -0,0 +1,126 @@
+<!-- GPS MODE -->
+<div id="gpsMode" class="mode-content">
+    <div class="section">
+        <h3>GPS Receiver</h3>
+        <p class="info-text" style="font-size: 11px; color: var(--text-dim); margin-bottom: 12px;">
+            Display live GPS data from gpsd &mdash; satellite sky view, signal strengths, position, velocity, DOP values, and timing.
+        </p>
+    </div>
+
+    <!-- Connection -->
+    <div class="section">
+        <h3>Connection</h3>
+        <div class="gps-connection-status">
+            <span class="gps-status-dot" id="gpsStatusDot"></span>
+            <span class="gps-status-text" id="gpsStatusText">Disconnected</span>
+        </div>
+        <div id="gpsDevicePath" style="font-size: 10px; color: var(--text-dim); margin-top: 4px; font-family: var(--font-mono);"></div>
+        <div style="display: flex; gap: 6px; margin-top: 8px;">
+            <button class="run-btn" id="gpsConnectBtn" onclick="GPS.connect()">Connect</button>
+            <button class="stop-btn" id="gpsDisconnectBtn" onclick="GPS.disconnect()" style="display: none;">Disconnect</button>
+        </div>
+    </div>
+
+    <!-- Fix Info -->
+    <div class="section">
+        <h3>Fix</h3>
+        <div class="gps-info-grid">
+            <div class="gps-info-item">
+                <span class="gps-info-label">Fix Type</span>
+                <span class="gps-info-value" id="gpsFixType">---</span>
+            </div>
+            <div class="gps-info-item">
+                <span class="gps-info-label">Satellites</span>
+                <span class="gps-info-value"><span id="gpsSatUsed">-</span> / <span id="gpsSatTotal">-</span></span>
+            </div>
+        </div>
+    </div>
+
+    <!-- Position -->
+    <div class="section">
+        <h3>Position</h3>
+        <div class="gps-info-grid">
+            <div class="gps-info-item">
+                <span class="gps-info-label">Latitude</span>
+                <span class="gps-info-value gps-mono" id="gpsLat">---</span>
+            </div>
+            <div class="gps-info-item">
+                <span class="gps-info-label">Longitude</span>
+                <span class="gps-info-value gps-mono" id="gpsLon">---</span>
+            </div>
+            <div class="gps-info-item">
+                <span class="gps-info-label">Altitude</span>
+                <span class="gps-info-value gps-mono" id="gpsAlt">---</span>
+            </div>
+            <div class="gps-info-item">
+                <span class="gps-info-label">Speed</span>
+                <span class="gps-info-value gps-mono" id="gpsSpeed">---</span>
+            </div>
+            <div class="gps-info-item">
+                <span class="gps-info-label">Heading</span>
+                <span class="gps-info-value gps-mono" id="gpsHeading">---</span>
+            </div>
+            <div class="gps-info-item">
+                <span class="gps-info-label">Climb</span>
+                <span class="gps-info-value gps-mono" id="gpsClimb">---</span>
+            </div>
+        </div>
+    </div>
+
+    <!-- DOP Values -->
+    <div class="section">
+        <h3>Dilution of Precision</h3>
+        <div class="gps-info-grid">
+            <div class="gps-info-item">
+                <span class="gps-info-label">HDOP</span>
+                <span class="gps-info-value gps-mono" id="gpsHdop">---</span>
+            </div>
+            <div class="gps-info-item">
+                <span class="gps-info-label">VDOP</span>
+                <span class="gps-info-value gps-mono" id="gpsVdop">---</span>
+            </div>
+            <div class="gps-info-item">
+                <span class="gps-info-label">PDOP</span>
+                <span class="gps-info-value gps-mono" id="gpsPdop">---</span>
+            </div>
+            <div class="gps-info-item">
+                <span class="gps-info-label">TDOP</span>
+                <span class="gps-info-value gps-mono" id="gpsTdop">---</span>
+            </div>
+            <div class="gps-info-item">
+                <span class="gps-info-label">GDOP</span>
+                <span class="gps-info-value gps-mono" id="gpsGdop">---</span>
+            </div>
+        </div>
+    </div>
+
+    <!-- Error Estimates -->
+    <div class="section">
+        <h3>Error Estimates</h3>
+        <div class="gps-info-grid">
+            <div class="gps-info-item">
+                <span class="gps-info-label">EPH (horiz)</span>
+                <span class="gps-info-value gps-mono" id="gpsEph">---</span>
+            </div>
+            <div class="gps-info-item">
+                <span class="gps-info-label">EPV (vert)</span>
+                <span class="gps-info-value gps-mono" id="gpsEpv">---</span>
+            </div>
+            <div class="gps-info-item">
+                <span class="gps-info-label">EPS (speed)</span>
+                <span class="gps-info-value gps-mono" id="gpsEps">---</span>
+            </div>
+        </div>
+    </div>
+
+    <!-- Timing -->
+    <div class="section">
+        <h3>GPS Time</h3>
+        <div class="gps-info-grid">
+            <div class="gps-info-item" style="grid-column: 1 / -1;">
+                <span class="gps-info-label">UTC</span>
+                <span class="gps-info-value gps-mono" id="gpsTime" style="font-size: 14px;">---</span>
+            </div>
+        </div>
+    </div>
+</div>

templates/partials/nav.html

@@ -87,6 +87,7 @@
         <div class="mode-nav-dropdown-menu">
             {{ mode_item('wifi', 'WiFi', '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><path d="M5 12.55a11 11 0 0 1 14.08 0"/><path d="M1.42 9a16 16 0 0 1 21.16 0"/><path d="M8.53 16.11a6 6 0 0 1 6.95 0"/><circle cx="12" cy="20" r="1" fill="currentColor" stroke="none"/></svg>') }}
             {{ mode_item('bluetooth', 'Bluetooth', '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><polyline points="6.5 6.5 17.5 17.5 12 22 12 2 17.5 6.5 6.5 17.5"/></svg>') }}
+            {{ mode_item('bt_locate', 'BT Locate', '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><circle cx="12" cy="10" r="3"/><path d="M12 21.7C17.3 17 20 13 20 10a8 8 0 1 0-16 0c0 3 2.7 7 8 11.7z"/><path d="M9.5 8.5l3 3 2-4-2 4-3 3"/></svg>') }}
         </div>
     </div>
 
@@ -120,6 +121,7 @@
             {{ mode_item('sstv', 'ISS SSTV', '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><rect x="3" y="3" width="18" height="18" rx="2"/><circle cx="12" cy="12" r="3"/><path d="M3 9h2"/><path d="M19 9h2"/><path d="M3 15h2"/><path d="M19 15h2"/></svg>') }}
             {{ mode_item('weathersat', 'Weather Sat', '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><circle cx="12" cy="12" r="10"/><path d="M2 12h20"/><path d="M12 2a15.3 15.3 0 0 1 4 10 15.3 15.3 0 0 1-4 10 15.3 15.3 0 0 1-4-10 15.3 15.3 0 0 1 4-10z"/></svg>') }}
             {{ mode_item('sstv_general', 'HF SSTV', '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><rect x="3" y="3" width="18" height="18" rx="2"/><circle cx="12" cy="12" r="3"/><path d="M16.24 7.76a6 6 0 0 1 0 8.49m-8.48-.01a6 6 0 0 1 0-8.49"/></svg>') }}
+            {{ mode_item('gps', 'GPS', '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><circle cx="12" cy="10" r="3"/><path d="M12 21.7C17.3 17 20 13 20 10a8 8 0 1 0-16 0c0 3 2.7 7 8 11.7z"/></svg>') }}
         </div>
     </div>
 
@@ -179,6 +181,7 @@
     {{ mobile_item('aprs', 'APRS', '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><path d="M20 10c0 6-8 12-8 12s-8-6-8-12a8 8 0 0 1 16 0Z"/><circle cx="12" cy="10" r="3"/></svg>') }}
     {{ mobile_item('wifi', 'WiFi', '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><path d="M5 12.55a11 11 0 0 1 14.08 0"/><path d="M8.53 16.11a6 6 0 0 1 6.95 0"/><circle cx="12" cy="20" r="1" fill="currentColor"/></svg>') }}
     {{ mobile_item('bluetooth', 'BT', '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><polyline points="6.5 6.5 17.5 17.5 12 22 12 2 17.5 6.5 6.5 17.5"/></svg>') }}
+    {{ mobile_item('bt_locate', 'Locate', '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><circle cx="12" cy="10" r="3"/><path d="M12 21.7C17.3 17 20 13 20 10a8 8 0 1 0-16 0c0 3 2.7 7 8 11.7z"/></svg>') }}
     {{ mobile_item('tscm', 'TSCM', '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><circle cx="11" cy="11" r="8"/><line x1="21" y1="21" x2="16.65" y2="16.65"/></svg>') }}
     {% if is_index_page %}
     {{ mobile_item('satellite', 'Sat', '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><path d="M13 7L9 3 5 7l4 4"/><path d="m17 11 4 4-4 4-4-4"/><path d="m8 12 4 4 6-6-4-4-6 6"/></svg>') }}
@@ -188,6 +191,7 @@
     {{ mobile_item('sstv', 'SSTV', '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><rect x="3" y="3" width="18" height="18" rx="2"/><circle cx="12" cy="12" r="3"/></svg>') }}
     {{ mobile_item('weathersat', 'WxSat', '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><circle cx="12" cy="12" r="10"/><path d="M2 12h20"/><path d="M12 2a15.3 15.3 0 0 1 4 10 15.3 15.3 0 0 1-4 10 15.3 15.3 0 0 1-4-10 15.3 15.3 0 0 1 4-10z"/></svg>') }}
     {{ mobile_item('sstv_general', 'HF SSTV', '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><rect x="3" y="3" width="18" height="18" rx="2"/><circle cx="12" cy="12" r="3"/></svg>') }}
+    {{ mobile_item('gps', 'GPS', '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><circle cx="12" cy="10" r="3"/><path d="M12 21.7C17.3 17 20 13 20 10a8 8 0 1 0-16 0c0 3 2.7 7 8 11.7z"/></svg>') }}
     {{ mobile_item('listening', 'Scanner', '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><rect x="3" y="3" width="18" height="18" rx="2"/><path d="M3 9h18"/><path d="M9 21V9"/></svg>') }}
     {{ mobile_item('spystations', 'Spy', '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><path d="M4.9 19.1C1 15.2 1 8.8 4.9 4.9"/><circle cx="12" cy="12" r="2"/><path d="M19.1 4.9C23 8.8 23 15.1 19.1 19"/></svg>') }}
     {{ mobile_item('meshtastic', 'Mesh', '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><circle cx="12" cy="12" r="10"/><circle cx="12" cy="12" r="3"/><path d="M12 2v4m0 12v4M2 12h4m12 0h4"/></svg>') }}

templates/satellite_dashboard.html

@@ -269,12 +269,42 @@
         let currentLocationSource = 'local';
         let agents = [];
 
-        const satellites = {
+        let satellites = {
             25544: { name: 'ISS (ZARYA)', color: '#00ffff' },
             40069: { name: 'METEOR-M2', color: '#9370DB' },
             57166: { name: 'METEOR-M2-3', color: '#ff00ff' }
         };
 
+        const satColors = ['#00ffff', '#9370DB', '#ff00ff', '#00ff00', '#ff6600', '#ffff00', '#ff69b4', '#7b68ee'];
+
+        function loadDashboardSatellites() {
+            fetch('/satellite/tracked?enabled=true')
+                .then(r => r.json())
+                .then(data => {
+                    if (data.status === 'success' && data.satellites && data.satellites.length > 0) {
+                        const newSats = {};
+                        const select = document.getElementById('satSelect');
+                        select.innerHTML = '';
+                        data.satellites.forEach((sat, i) => {
+                            const norad = parseInt(sat.norad_id);
+                            newSats[norad] = {
+                                name: sat.name,
+                                color: satellites[norad]?.color || satColors[i % satColors.length]
+                            };
+                            const opt = document.createElement('option');
+                            opt.value = norad;
+                            opt.textContent = sat.name;
+                            select.appendChild(opt);
+                        });
+                        satellites = newSats;
+                        // Default to ISS if available
+                        if (newSats[25544]) select.value = '25544';
+                        selectedSatellite = parseInt(select.value);
+                    }
+                })
+                .catch(() => {});
+        }
+
         function onSatelliteChange() {
             const select = document.getElementById('satSelect');
             selectedSatellite = parseInt(select.value);
@@ -331,6 +361,7 @@
         }
 
         document.addEventListener('DOMContentLoaded', () => {
+            loadDashboardSatellites();
             setupEmbeddedMode();
             const usedShared = applySharedObserverLocation();
             initGroundMap();

tests/test_bt_locate.py

@@ -0,0 +1,278 @@
+"""Tests for BT Locate — Bluetooth SAR Device Location System."""
+
+from unittest.mock import MagicMock, patch
+
+import pytest
+
+try:
+    from cryptography.hazmat.primitives.ciphers import Cipher, algorithms
+    from cryptography.hazmat.primitives.ciphers import modes as cipher_modes
+    HAS_CRYPTOGRAPHY = True
+except ImportError:
+    HAS_CRYPTOGRAPHY = False
+
+from utils.bt_locate import (
+    DistanceEstimator,
+    Environment,
+    LocateSession,
+    LocateTarget,
+    get_locate_session,
+    resolve_rpa,
+    start_locate_session,
+    stop_locate_session,
+)
+
+
+class TestResolveRPA:
+    """Test BLE Resolvable Private Address resolution."""
+
+    @pytest.mark.skipif(not HAS_CRYPTOGRAPHY, reason="cryptography not installed")
+    def test_resolve_rpa_valid_match(self):
+        """Test RPA resolution with known IRK/address pair.
+
+        Uses test vector: IRK = all zeros, we generate matching address.
+        """
+        # The ah() function: encrypt(IRK, 0x00..00 || prand) then take last 3 bytes
+
+        irk = b'\x00' * 16
+        # Choose prand with upper 2 bits = 01 (resolvable)
+        prand = bytes([0x40, 0x00, 0x01])
+        plaintext = b'\x00' * 13 + prand
+        c = Cipher(algorithms.AES(irk), cipher_modes.ECB())
+        enc = c.encryptor()
+        encrypted = enc.update(plaintext) + enc.finalize()
+        hash_bytes = encrypted[13:16]
+
+        # Build address: prand || hash
+        addr_bytes = prand + hash_bytes
+        address = ':'.join(f'{b:02X}' for b in addr_bytes)
+
+        assert resolve_rpa(irk, address) is True
+
+    def test_resolve_rpa_invalid_address(self):
+        """Test RPA resolution with non-matching address."""
+        irk = b'\x00' * 16
+        # Non-resolvable address (upper 2 bits != 01)
+        assert resolve_rpa(irk, 'FF:FF:FF:FF:FF:FF') is False
+
+    @pytest.mark.skipif(not HAS_CRYPTOGRAPHY, reason="cryptography not installed")
+    def test_resolve_rpa_wrong_irk(self):
+        """Test RPA resolution with wrong IRK."""
+        irk = b'\x00' * 16
+        prand = bytes([0x40, 0x00, 0x01])
+        plaintext = b'\x00' * 13 + prand
+        c = Cipher(algorithms.AES(irk), cipher_modes.ECB())
+        enc = c.encryptor()
+        encrypted = enc.update(plaintext) + enc.finalize()
+        hash_bytes = encrypted[13:16]
+        addr_bytes = prand + hash_bytes
+        address = ':'.join(f'{b:02X}' for b in addr_bytes)
+
+        # Different IRK should fail
+        wrong_irk = b'\x01' * 16
+        assert resolve_rpa(wrong_irk, address) is False
+
+    def test_resolve_rpa_short_address(self):
+        """Test with invalid short address."""
+        irk = b'\x00' * 16
+        assert resolve_rpa(irk, 'AA:BB') is False
+
+    def test_resolve_rpa_empty(self):
+        """Test with empty inputs."""
+        assert resolve_rpa(b'\x00' * 16, '') is False
+
+
+class TestDistanceEstimator:
+    """Test RSSI-to-distance estimation."""
+
+    def test_free_space_distance(self):
+        estimator = DistanceEstimator(path_loss_exponent=2.0, rssi_at_1m=-59)
+        # At 1m, RSSI should be -59, so distance should be ~1m
+        d = estimator.estimate(-59)
+        assert abs(d - 1.0) < 0.01
+
+    def test_weaker_signal_farther(self):
+        estimator = DistanceEstimator(path_loss_exponent=2.0)
+        d1 = estimator.estimate(-50)
+        d2 = estimator.estimate(-70)
+        assert d2 > d1
+
+    def test_indoor_closer_estimate(self):
+        """Indoor (n=3) should estimate closer distance for same RSSI."""
+        free_space = DistanceEstimator(path_loss_exponent=2.0)
+        indoor = DistanceEstimator(path_loss_exponent=3.0)
+        rssi = -75
+        d_free = free_space.estimate(rssi)
+        d_indoor = indoor.estimate(rssi)
+        # With higher path loss exponent, same RSSI means closer distance
+        assert d_indoor < d_free
+
+    def test_proximity_band_immediate(self):
+        assert DistanceEstimator.proximity_band(0.5) == 'IMMEDIATE'
+
+    def test_proximity_band_near(self):
+        assert DistanceEstimator.proximity_band(3.0) == 'NEAR'
+
+    def test_proximity_band_far(self):
+        assert DistanceEstimator.proximity_band(10.0) == 'FAR'
+
+
+class TestLocateTarget:
+    """Test target matching."""
+
+    def test_match_by_mac(self):
+        target = LocateTarget(mac_address='AA:BB:CC:DD:EE:FF')
+        device = MagicMock()
+        device.device_id = 'other'
+        device.address = 'AA:BB:CC:DD:EE:FF'
+        device.name = None
+        assert target.matches(device) is True
+
+    def test_match_by_mac_case_insensitive(self):
+        target = LocateTarget(mac_address='aa:bb:cc:dd:ee:ff')
+        device = MagicMock()
+        device.device_id = 'other'
+        device.address = 'AA:BB:CC:DD:EE:FF'
+        device.name = None
+        assert target.matches(device) is True
+
+    def test_match_by_name_pattern(self):
+        target = LocateTarget(name_pattern='iPhone')
+        device = MagicMock()
+        device.device_id = 'other'
+        device.address = '00:00:00:00:00:00'
+        device.name = "John's iPhone 15"
+        assert target.matches(device) is True
+
+    def test_no_match(self):
+        target = LocateTarget(mac_address='AA:BB:CC:DD:EE:FF')
+        device = MagicMock()
+        device.device_id = 'other'
+        device.address = '11:22:33:44:55:66'
+        device.name = None
+        assert target.matches(device) is False
+
+    def test_match_by_device_id(self):
+        target = LocateTarget(device_id='my-device-123')
+        device = MagicMock()
+        device.device_id = 'my-device-123'
+        device.address = '00:00:00:00:00:00'
+        device.name = None
+        assert target.matches(device) is True
+
+    def test_to_dict(self):
+        target = LocateTarget(mac_address='AA:BB:CC:DD:EE:FF', known_name='Test')
+        d = target.to_dict()
+        assert d['mac_address'] == 'AA:BB:CC:DD:EE:FF'
+        assert d['known_name'] == 'Test'
+
+
+class TestLocateSession:
+    """Test locate session lifecycle."""
+
+    @patch('utils.bt_locate.get_bluetooth_scanner')
+    def test_start_stop(self, mock_get_scanner):
+        mock_scanner = MagicMock()
+        mock_get_scanner.return_value = mock_scanner
+
+        target = LocateTarget(mac_address='AA:BB:CC:DD:EE:FF')
+        session = LocateSession(target, Environment.OUTDOOR)
+        session.start()
+
+        assert session.active is True
+        mock_scanner.add_device_callback.assert_called_once()
+
+        session.stop()
+        assert session.active is False
+        mock_scanner.remove_device_callback.assert_called_once()
+
+    @patch('utils.bt_locate.get_bluetooth_scanner')
+    @patch('utils.bt_locate.get_current_position')
+    def test_detection_creates_trail_point(self, mock_gps, mock_get_scanner):
+        mock_scanner = MagicMock()
+        mock_get_scanner.return_value = mock_scanner
+        mock_gps.return_value = None  # No GPS
+
+        target = LocateTarget(mac_address='AA:BB:CC:DD:EE:FF')
+        session = LocateSession(target, Environment.OUTDOOR)
+        session.start()
+
+        # Simulate device callback
+        device = MagicMock()
+        device.device_id = 'test'
+        device.address = 'AA:BB:CC:DD:EE:FF'
+        device.name = 'Test Device'
+        device.rssi_current = -65
+
+        session._on_device(device)
+
+        assert session.detection_count == 1
+        assert len(session.trail) == 1
+        assert session.trail[0].rssi == -65
+
+    @patch('utils.bt_locate.get_bluetooth_scanner')
+    def test_non_matching_device_ignored(self, mock_get_scanner):
+        mock_scanner = MagicMock()
+        mock_get_scanner.return_value = mock_scanner
+
+        target = LocateTarget(mac_address='AA:BB:CC:DD:EE:FF')
+        session = LocateSession(target, Environment.OUTDOOR)
+        session.start()
+
+        device = MagicMock()
+        device.device_id = 'other'
+        device.address = '11:22:33:44:55:66'
+        device.name = None
+        device.rssi_current = -70
+
+        session._on_device(device)
+        assert session.detection_count == 0
+
+    @patch('utils.bt_locate.get_bluetooth_scanner')
+    def test_get_status(self, mock_get_scanner):
+        mock_scanner = MagicMock()
+        mock_get_scanner.return_value = mock_scanner
+
+        target = LocateTarget(mac_address='AA:BB:CC:DD:EE:FF')
+        session = LocateSession(target, Environment.FREE_SPACE)
+        session.start()
+
+        status = session.get_status()
+        assert status['active'] is True
+        assert status['environment'] == 'FREE_SPACE'
+        assert status['detection_count'] == 0
+
+
+class TestModuleLevelSessionManagement:
+    """Test module-level session functions."""
+
+    @patch('utils.bt_locate.get_bluetooth_scanner')
+    def test_start_and_get_session(self, mock_get_scanner):
+        mock_scanner = MagicMock()
+        mock_get_scanner.return_value = mock_scanner
+
+        target = LocateTarget(mac_address='AA:BB:CC:DD:EE:FF')
+        session = start_locate_session(target)
+
+        assert get_locate_session() is session
+        assert session.active is True
+
+        stop_locate_session()
+        assert get_locate_session() is None
+
+    @patch('utils.bt_locate.get_bluetooth_scanner')
+    def test_start_replaces_existing_session(self, mock_get_scanner):
+        mock_scanner = MagicMock()
+        mock_get_scanner.return_value = mock_scanner
+
+        target1 = LocateTarget(mac_address='AA:BB:CC:DD:EE:FF')
+        session1 = start_locate_session(target1)
+
+        target2 = LocateTarget(mac_address='11:22:33:44:55:66')
+        session2 = start_locate_session(target2)
+
+        assert get_locate_session() is session2
+        assert session1.active is False
+        assert session2.active is True
+
+        stop_locate_session()

tests/test_dsc.py

@@ -313,8 +313,9 @@ class TestDSCDecoder:
     def test_decode_mmsi_with_leading_zeros(self, decoder):
         """Test MMSI decoding handles leading zeros."""
         # Coast station: 002320001
-        # 00-23-20-00-01 -> [0, 23, 20, 0, 1]
+        # Padded to 10 digits: 0002320001
-        symbols = [0, 23, 20, 0, 1]
+        # BCD pairs: 00-02-32-00-01 -> [0, 2, 32, 0, 1]
+        symbols = [0, 2, 32, 0, 1]
         result = decoder._decode_mmsi(symbols)
         assert result == '002320001'
 
@@ -328,14 +329,16 @@ class TestDSCDecoder:
         # Symbols > 99 should be treated as 0
         symbols = [100, 32, 12, 34, 56]
         result = decoder._decode_mmsi(symbols)
-        # First symbol becomes 00
+        # First symbol (100) becomes 00, padded result "0032123456",
-        assert result == '003212345'[-9:]
+        # trim leading pad digit -> "032123456"
+        assert result == '032123456'
 
     def test_decode_position_northeast(self, decoder):
         """Test position decoding for NE quadrant."""
         # Quadrant 10 = NE (lat+, lon+)
         # Position: 51°30'N, 0°10'E
-        symbols = [10, 51, 30, 0, 10, 0, 0, 0, 0, 0]
+        # lon_deg = symbols[3]*100 + symbols[4] = 0, lon_min = symbols[5] = 10
+        symbols = [10, 51, 30, 0, 0, 10, 0, 0, 0, 0]
         result = decoder._decode_position(symbols)
 
         assert result is not None

utils/bluetooth/aggregator.py

@@ -606,6 +606,12 @@ class DeviceAggregator:
 
         return result
 
+    def get_fingerprint_mac_count(self, fingerprint_id: str) -> int:
+        """Return how many distinct device_ids share a fingerprint."""
+        with self._lock:
+            device_ids = self._fingerprint_to_devices.get(fingerprint_id)
+            return len(device_ids) if device_ids else 0
+
     def prune_ring_buffer(self) -> int:
         """Prune old observations from ring buffer."""
         return self._ring_buffer.prune_old()

utils/bluetooth/constants.py

@@ -101,6 +101,7 @@ ADDRESS_TYPE_RANDOM = 'random'
 ADDRESS_TYPE_RANDOM_STATIC = 'random_static'
 ADDRESS_TYPE_RPA = 'rpa'  # Resolvable Private Address
 ADDRESS_TYPE_NRPA = 'nrpa'  # Non-Resolvable Private Address
+ADDRESS_TYPE_UUID = 'uuid'  # CoreBluetooth platform UUID (macOS, no real MAC available)
 
 # =============================================================================
 # PROTOCOL TYPES
@@ -278,3 +279,59 @@ MINOR_WEARABLE = {
     0x04: 'Helmet',
     0x05: 'Glasses',
 }
+
+# =============================================================================
+# BLE APPEARANCE CODES (GAP Appearance values)
+# =============================================================================
+
+BLE_APPEARANCE_NAMES: dict[int, str] = {
+    0: 'Unknown',
+    64: 'Phone',
+    128: 'Computer',
+    192: 'Watch',
+    193: 'Sports Watch',
+    256: 'Clock',
+    320: 'Display',
+    384: 'Remote Control',
+    448: 'Eye Glasses',
+    512: 'Tag',
+    576: 'Keyring',
+    640: 'Media Player',
+    704: 'Barcode Scanner',
+    768: 'Thermometer',
+    832: 'Heart Rate Sensor',
+    896: 'Blood Pressure',
+    960: 'HID',
+    961: 'Keyboard',
+    962: 'Mouse',
+    963: 'Joystick',
+    964: 'Gamepad',
+    965: 'Digitizer Tablet',
+    966: 'Card Reader',
+    967: 'Digital Pen',
+    968: 'Barcode Scanner (HID)',
+    1024: 'Glucose Monitor',
+    1088: 'Running Speed Sensor',
+    1152: 'Cycling',
+    1216: 'Control Device',
+    1280: 'Network Device',
+    1344: 'Sensor',
+    1408: 'Light Fixture',
+    1472: 'Fan',
+    1536: 'HVAC',
+    1600: 'Access Control',
+    1664: 'Motorized Device',
+    1728: 'Power Device',
+    1792: 'Light Source',
+    3136: 'Pulse Oximeter',
+    3200: 'Weight Scale',
+    3264: 'Personal Mobility',
+    5184: 'Outdoor Sports Activity',
+}
+
+
+def get_appearance_name(code: int | None) -> str | None:
+    """Look up a human-readable name for a BLE appearance code."""
+    if code is None:
+        return None
+    return BLE_APPEARANCE_NAMES.get(code)

utils/bluetooth/device_key.py

@@ -12,6 +12,7 @@ from typing import Optional
 from .constants import (
     ADDRESS_TYPE_PUBLIC,
     ADDRESS_TYPE_RANDOM_STATIC,
+    ADDRESS_TYPE_UUID,
 )
 
 
@@ -46,10 +47,14 @@ def generate_device_key(
     if identity_address:
         return f"id:{identity_address.upper()}"
 
-    # Priority 2: Use public or random_static addresses directly
+    # Priority 2: Use public or random_static addresses directly (not platform UUIDs)
     if address_type in (ADDRESS_TYPE_PUBLIC, ADDRESS_TYPE_RANDOM_STATIC):
         return f"mac:{address.upper()}"
 
+    # Priority 2b: CoreBluetooth UUIDs are stable per-system, use as identifier
+    if address_type == ADDRESS_TYPE_UUID:
+        return f"uuid:{address.upper()}"
+
     # Priority 3: Generate fingerprint hash for random addresses
     return _generate_fingerprint_key(address, name, manufacturer_id, service_uuids)
 
@@ -102,7 +107,7 @@ def is_randomized_mac(address_type: str) -> bool:
     Returns:
         True if the address is randomized, False otherwise.
     """
-    return address_type not in (ADDRESS_TYPE_PUBLIC, ADDRESS_TYPE_RANDOM_STATIC)
+    return address_type not in (ADDRESS_TYPE_PUBLIC, ADDRESS_TYPE_RANDOM_STATIC, ADDRESS_TYPE_UUID)
 
 
 def extract_key_type(device_key: str) -> str:

utils/bluetooth/fallback_scanner.py

@@ -24,8 +24,12 @@ from .constants import (
     BLUETOOTHCTL_TIMEOUT,
     ADDRESS_TYPE_PUBLIC,
     ADDRESS_TYPE_RANDOM,
+    ADDRESS_TYPE_UUID,
     MANUFACTURER_NAMES,
 )
+
+# CoreBluetooth UUID pattern: 8-4-4-4-12 hex digits
+_CB_UUID_RE = re.compile(r'^[0-9A-Fa-f]{8}-[0-9A-Fa-f]{4}-[0-9A-Fa-f]{4}-[0-9A-Fa-f]{4}-[0-9A-Fa-f]{12}$')
 from .models import BTObservation
 
 logger = logging.getLogger(__name__)
@@ -132,7 +136,10 @@ class BleakScanner:
         """Convert bleak device to BTObservation."""
         # Determine address type from address format
         address_type = ADDRESS_TYPE_PUBLIC
-        if device.address and ':' in device.address:
+        if device.address and _CB_UUID_RE.match(device.address):
+            # macOS CoreBluetooth returns a platform UUID instead of a real MAC
+            address_type = ADDRESS_TYPE_UUID
+        elif device.address and ':' in device.address:
             # Check if first byte indicates random address
             first_byte = int(device.address.split(':')[0], 16)
             if (first_byte & 0xC0) == 0xC0:  # Random static

utils/bluetooth/irk_extractor.py

@@ -0,0 +1,198 @@
+"""
+IRK Extractor — Extract Identity Resolving Keys from paired Bluetooth devices.
+
+Supports macOS (com.apple.Bluetooth.plist) and Linux (BlueZ info files).
+"""
+
+from __future__ import annotations
+
+import logging
+import platform
+import time
+from pathlib import Path
+
+logger = logging.getLogger('intercept.bt.irk_extractor')
+
+# Cache paired IRKs for 30 seconds to avoid repeated disk reads
+_cache: list[dict] | None = None
+_cache_time: float = 0
+_CACHE_TTL = 30.0
+
+
+def get_paired_irks() -> list[dict]:
+    """Return paired Bluetooth devices that have IRKs.
+
+    Each entry is a dict with keys:
+        - name: Device name (str or None)
+        - address: Bluetooth address (str)
+        - irk_hex: 32-char hex string of the 16-byte IRK
+        - address_type: 'random' or 'public' (str or None)
+
+    Results are cached for 30 seconds.
+    """
+    global _cache, _cache_time
+
+    now = time.monotonic()
+    if _cache is not None and (now - _cache_time) < _CACHE_TTL:
+        return _cache
+
+    system = platform.system()
+    try:
+        if system == 'Darwin':
+            results = _extract_macos()
+        elif system == 'Linux':
+            results = _extract_linux()
+        else:
+            logger.debug(f"IRK extraction not supported on {system}")
+            results = []
+    except Exception:
+        logger.exception("Failed to extract paired IRKs")
+        results = []
+
+    _cache = results
+    _cache_time = now
+    return results
+
+
+def _extract_macos() -> list[dict]:
+    """Extract IRKs from macOS Bluetooth plist."""
+    import plistlib
+
+    plist_path = Path('/Library/Preferences/com.apple.Bluetooth.plist')
+    if not plist_path.exists():
+        logger.debug("macOS Bluetooth plist not found")
+        return []
+
+    with open(plist_path, 'rb') as f:
+        plist = plistlib.load(f)
+
+    devices = []
+
+    cache_data = plist.get('CoreBluetoothCache', {})
+
+    # CoreBluetoothCache contains BLE device info including IRKs
+    for device_uuid, device_info in cache_data.items():
+        if not isinstance(device_info, dict):
+            continue
+
+        irk = device_info.get('IRK')
+        if irk is None:
+            continue
+
+        # IRK is stored as bytes (16 bytes)
+        if isinstance(irk, bytes) and len(irk) == 16:
+            irk_hex = irk.hex()
+        elif isinstance(irk, str):
+            irk_hex = irk.replace('-', '').replace(' ', '')
+            if len(irk_hex) != 32:
+                continue
+        else:
+            continue
+
+        name = device_info.get('Name') or device_info.get('DeviceName')
+        address = device_info.get('DeviceAddress', device_uuid)
+        addr_type = 'random' if device_info.get('AddressType', 1) == 1 else 'public'
+
+        devices.append({
+            'name': name,
+            'address': str(address),
+            'irk_hex': irk_hex,
+            'address_type': addr_type,
+        })
+
+    # Also check LEPairedDevices / PairedDevices structures
+    for section_key in ('LEPairedDevices', 'PairedDevices'):
+        section = plist.get(section_key, {})
+        if not isinstance(section, dict):
+            continue
+        for addr, dev_info in section.items():
+            if not isinstance(dev_info, dict):
+                continue
+            irk = dev_info.get('IRK') or dev_info.get('IdentityResolvingKey')
+            if irk is None:
+                continue
+
+            if isinstance(irk, bytes) and len(irk) == 16:
+                irk_hex = irk.hex()
+            elif isinstance(irk, str):
+                irk_hex = irk.replace('-', '').replace(' ', '')
+                if len(irk_hex) != 32:
+                    continue
+            else:
+                continue
+
+            # Skip if we already have this IRK
+            if any(d['irk_hex'] == irk_hex for d in devices):
+                continue
+
+            name = dev_info.get('Name') or dev_info.get('DeviceName')
+            addr_type = 'random' if dev_info.get('AddressType', 1) == 1 else 'public'
+
+            devices.append({
+                'name': name,
+                'address': str(addr),
+                'irk_hex': irk_hex,
+                'address_type': addr_type,
+            })
+
+    logger.info(f"Extracted {len(devices)} IRK(s) from macOS paired devices")
+    return devices
+
+
+def _extract_linux() -> list[dict]:
+    """Extract IRKs from Linux BlueZ info files.
+
+    BlueZ stores paired device info at:
+    /var/lib/bluetooth/<adapter_mac>/<device_mac>/info
+    """
+    import configparser
+
+    bt_root = Path('/var/lib/bluetooth')
+    if not bt_root.exists():
+        logger.debug("BlueZ bluetooth directory not found")
+        return []
+
+    devices = []
+
+    for adapter_dir in bt_root.iterdir():
+        if not adapter_dir.is_dir():
+            continue
+        for device_dir in adapter_dir.iterdir():
+            if not device_dir.is_dir():
+                continue
+
+            info_file = device_dir / 'info'
+            if not info_file.exists():
+                continue
+
+            config = configparser.ConfigParser()
+            try:
+                config.read(str(info_file))
+            except (configparser.Error, OSError):
+                continue
+
+            if not config.has_section('IdentityResolvingKey'):
+                continue
+
+            irk_hex = config.get('IdentityResolvingKey', 'Key', fallback=None)
+            if not irk_hex:
+                continue
+
+            # BlueZ stores as hex string, may or may not have separators
+            irk_hex = irk_hex.replace(' ', '').replace('-', '')
+            if len(irk_hex) != 32:
+                continue
+
+            name = config.get('General', 'Name', fallback=None)
+            address = device_dir.name  # Directory name is the MAC address
+            addr_type = config.get('General', 'AddressType', fallback=None)
+
+            devices.append({
+                'name': name,
+                'address': address,
+                'irk_hex': irk_hex,
+                'address_type': addr_type,
+            })
+
+    logger.info(f"Extracted {len(devices)} IRK(s) from BlueZ paired devices")
+    return devices

utils/bluetooth/models.py

@@ -18,6 +18,7 @@ from .constants import (
     RANGE_UNKNOWN,
     PROTOCOL_BLE,
     PROXIMITY_UNKNOWN,
+    get_appearance_name,
 )
 
 # Import tracker types (will be available after tracker_signatures module loads)
@@ -165,6 +166,10 @@ class BTDeviceAggregate:
     risk_score: float = 0.0  # 0.0 to 1.0
     risk_factors: list[str] = field(default_factory=list)
 
+    # IRK (Identity Resolving Key) from paired device database
+    irk_hex: Optional[str] = None  # 32-char hex if known
+    irk_source_name: Optional[str] = None  # Name from paired DB
+
     # Payload fingerprint (survives MAC randomization)
     payload_fingerprint_id: Optional[str] = None
     payload_fingerprint_stability: float = 0.0
@@ -296,6 +301,11 @@ class BTDeviceAggregate:
                 'risk_factors': self.risk_factors,
             },
 
+            # IRK
+            'has_irk': self.irk_hex is not None,
+            'irk_hex': self.irk_hex,
+            'irk_source_name': self.irk_source_name,
+
             # Fingerprint
             'fingerprint': {
                 'id': self.payload_fingerprint_id,
@@ -319,15 +329,32 @@ class BTDeviceAggregate:
             'rssi_current': self.rssi_current,
             'rssi_median': round(self.rssi_median, 1) if self.rssi_median else None,
             'rssi_ema': round(self.rssi_ema, 1) if self.rssi_ema else None,
+            'rssi_min': self.rssi_min,
+            'rssi_max': self.rssi_max,
+            'rssi_variance': round(self.rssi_variance, 2) if self.rssi_variance else None,
             'range_band': self.range_band,
             'proximity_band': self.proximity_band,
             'estimated_distance_m': round(self.estimated_distance_m, 2) if self.estimated_distance_m else None,
             'distance_confidence': round(self.distance_confidence, 2),
             'is_randomized_mac': self.is_randomized_mac,
             'last_seen': self.last_seen.isoformat(),
+            'first_seen': self.first_seen.isoformat(),
             'age_seconds': self.age_seconds,
+            'duration_seconds': self.duration_seconds,
             'seen_count': self.seen_count,
+            'seen_rate': round(self.seen_rate, 2),
+            'tx_power': self.tx_power,
+            'manufacturer_id': self.manufacturer_id,
+            'appearance': self.appearance,
+            'appearance_name': get_appearance_name(self.appearance),
+            'is_connectable': self.is_connectable,
+            'service_uuids': self.service_uuids,
+            'service_data': {k: v.hex() for k, v in self.service_data.items()},
+            'manufacturer_bytes': self.manufacturer_bytes.hex() if self.manufacturer_bytes else None,
             'heuristic_flags': self.heuristic_flags,
+            'is_persistent': self.is_persistent,
+            'is_beacon_like': self.is_beacon_like,
+            'is_strong_stable': self.is_strong_stable,
             'in_baseline': self.in_baseline,
             'seen_before': self.seen_before,
             # Tracker info for list view
@@ -336,7 +363,12 @@ class BTDeviceAggregate:
             'tracker_name': self.tracker_name,
             'tracker_confidence': self.tracker_confidence,
             'tracker_confidence_score': round(self.tracker_confidence_score, 2),
+            'tracker_evidence': self.tracker_evidence,
             'risk_score': round(self.risk_score, 2),
+            'risk_factors': self.risk_factors,
+            'has_irk': self.irk_hex is not None,
+            'irk_hex': self.irk_hex,
+            'irk_source_name': self.irk_source_name,
             'fingerprint_id': self.payload_fingerprint_id,
         }
 

utils/bluetooth/scanner.py

@@ -24,7 +24,9 @@ from .constants import (
 )
 from .dbus_scanner import DBusScanner
 from .fallback_scanner import FallbackScanner
+from .ubertooth_scanner import UbertoothScanner
 from .heuristics import HeuristicsEngine
+from .irk_extractor import get_paired_irks
 from .models import BTDeviceAggregate, BTObservation, ScanStatus, SystemCapabilities
 
 logger = logging.getLogger(__name__)
@@ -57,6 +59,7 @@ class BluetoothScanner:
         # Scanner backends
         self._dbus_scanner: Optional[DBusScanner] = None
         self._fallback_scanner: Optional[FallbackScanner] = None
+        self._ubertooth_scanner: Optional[UbertoothScanner] = None
         self._active_backend: Optional[str] = None
 
         # Event queue for SSE streaming
@@ -66,7 +69,7 @@ class BluetoothScanner:
         self._scan_timer: Optional[threading.Timer] = None
 
         # Callbacks
-        self._on_device_updated: Optional[Callable[[BTDeviceAggregate], None]] = None
+        self._on_device_updated_callbacks: list[Callable[[BTDeviceAggregate], None]] = []
 
         # Capability check result
         self._capabilities: Optional[SystemCapabilities] = None
@@ -113,6 +116,8 @@ class BluetoothScanner:
 
             if mode == 'dbus':
                 started, backend_used = self._start_dbus(adapter, transport, rssi_threshold)
+            elif mode == 'ubertooth':
+                started, backend_used = self._start_ubertooth()
 
             # Fallback: try non-DBus methods if DBus failed or wasn't requested
             if not started and (original_mode == 'auto' or mode in ('bleak', 'hcitool', 'bluetoothctl')):
@@ -168,6 +173,18 @@ class BluetoothScanner:
             logger.warning(f"DBus scanner failed: {e}")
         return False, None
 
+    def _start_ubertooth(self) -> tuple[bool, Optional[str]]:
+        """Start Ubertooth One scanner."""
+        try:
+            self._ubertooth_scanner = UbertoothScanner(
+                on_observation=self._handle_observation,
+            )
+            if self._ubertooth_scanner.start():
+                return True, 'ubertooth'
+        except Exception as e:
+            logger.warning(f"Ubertooth scanner failed: {e}")
+        return False, None
+
     def _start_fallback(self, adapter: str, preferred: str) -> tuple[bool, Optional[str]]:
         """Start fallback scanner."""
         try:
@@ -204,6 +221,10 @@ class BluetoothScanner:
                 self._fallback_scanner.stop()
                 self._fallback_scanner = None
 
+            if self._ubertooth_scanner:
+                self._ubertooth_scanner.stop()
+                self._ubertooth_scanner = None
+
             # Update status
             self._status.is_scanning = False
             self._active_backend = None
@@ -216,6 +237,47 @@ class BluetoothScanner:
 
             logger.info("Bluetooth scan stopped")
 
+    def _match_irk(self, device: BTDeviceAggregate) -> None:
+        """Check if a device address resolves against any paired IRK."""
+        if device.irk_hex is not None:
+            return  # Already matched
+
+        address = device.address
+        if not address or len(address.replace(':', '').replace('-', '')) not in (12, 32):
+            return
+
+        # Only attempt RPA resolution on 6-byte addresses
+        addr_clean = address.replace(':', '').replace('-', '')
+        if len(addr_clean) != 12:
+            return
+
+        try:
+            paired = get_paired_irks()
+        except Exception:
+            return
+
+        if not paired:
+            return
+
+        try:
+            from utils.bt_locate import resolve_rpa
+        except ImportError:
+            return
+
+        for entry in paired:
+            irk_hex = entry.get('irk_hex', '')
+            if not irk_hex or len(irk_hex) != 32:
+                continue
+            try:
+                irk = bytes.fromhex(irk_hex)
+                if resolve_rpa(irk, address):
+                    device.irk_hex = irk_hex
+                    device.irk_source_name = entry.get('name')
+                    logger.debug(f"IRK match for {address}: {entry.get('name', 'unnamed')}")
+                    return
+            except Exception:
+                continue
+
     def _handle_observation(self, observation: BTObservation) -> None:
         """Handle incoming observation from scanner backend."""
         try:
@@ -225,20 +287,35 @@ class BluetoothScanner:
             # Evaluate heuristics
             self._heuristics.evaluate(device)
 
+            # Check for IRK match
+            self._match_irk(device)
+
             # Update device count
             with self._lock:
                 self._status.devices_found = self._aggregator.device_count
 
+            # Build summary with MAC cluster count
+            summary = device.to_summary_dict()
+            if device.payload_fingerprint_id:
+                summary['mac_cluster_count'] = self._aggregator.get_fingerprint_mac_count(
+                    device.payload_fingerprint_id
+                )
+            else:
+                summary['mac_cluster_count'] = 0
+
             # Queue event
             self._queue_event({
                 'type': 'device',
                 'action': 'update',
-                'device': device.to_summary_dict(),
+                'device': summary,
             })
 
-            # Callback
+            # Callbacks
-            if self._on_device_updated:
+            for cb in self._on_device_updated_callbacks:
-                self._on_device_updated(device)
+                try:
+                    cb(device)
+                except Exception as cb_err:
+                    logger.error(f"Device callback error: {cb_err}")
 
         except Exception as e:
             logger.error(f"Error handling observation: {e}")
@@ -368,13 +445,40 @@ class BluetoothScanner:
         return self._capabilities
 
     def set_on_device_updated(self, callback: Callable[[BTDeviceAggregate], None]) -> None:
-        """Set callback for device updates."""
+        """Set callback for device updates (legacy, adds to callback list)."""
-        self._on_device_updated = callback
+        self.add_device_callback(callback)
+
+    def add_device_callback(self, callback: Callable[[BTDeviceAggregate], None]) -> None:
+        """Add a callback for device updates."""
+        if callback not in self._on_device_updated_callbacks:
+            self._on_device_updated_callbacks.append(callback)
+
+    def remove_device_callback(self, callback: Callable[[BTDeviceAggregate], None]) -> None:
+        """Remove a device update callback."""
+        if callback in self._on_device_updated_callbacks:
+            self._on_device_updated_callbacks.remove(callback)
 
     @property
     def is_scanning(self) -> bool:
-        """Check if scanning is active."""
+        """Check if scanning is active.
-        return self._status.is_scanning
+
+        Cross-checks the backend scanner state, since bleak scans can
+        expire silently without calling stop_scan().
+        """
+        if not self._status.is_scanning:
+            return False
+
+        # Detect backends that finished on their own (e.g. bleak timeout)
+        backend_alive = (
+            (self._dbus_scanner and self._dbus_scanner.is_scanning)
+            or (self._fallback_scanner and self._fallback_scanner.is_scanning)
+            or (self._ubertooth_scanner and self._ubertooth_scanner.is_scanning)
+        )
+        if not backend_alive:
+            self._status.is_scanning = False
+            return False
+
+        return True
 
     @property
     def device_count(self) -> int:

utils/bt_locate.py

@@ -0,0 +1,562 @@
+"""
+BT Locate — Bluetooth SAR Device Location System.
+
+Provides GPS-tagged signal trail mapping, RPA resolution, environment-aware
+distance estimation, and proximity alerts for search and rescue operations.
+"""
+
+from __future__ import annotations
+
+import logging
+import queue
+import threading
+from dataclasses import dataclass
+from datetime import datetime
+from enum import Enum
+
+from utils.bluetooth.models import BTDeviceAggregate
+from utils.bluetooth.scanner import BluetoothScanner, get_bluetooth_scanner
+from utils.gps import get_current_position
+
+logger = logging.getLogger('intercept.bt_locate')
+
+# Maximum trail points to retain
+MAX_TRAIL_POINTS = 500
+
+# EMA smoothing factor for RSSI
+EMA_ALPHA = 0.3
+
+
+class Environment(Enum):
+    """RF propagation environment presets."""
+    FREE_SPACE = 2.0
+    OUTDOOR = 2.2
+    INDOOR = 3.0
+    CUSTOM = 0.0  # user-provided exponent
+
+
+def resolve_rpa(irk: bytes, address: str) -> bool:
+    """
+    Resolve a BLE Resolvable Private Address against an Identity Resolving Key.
+
+    Implements the Bluetooth Core Spec ah() function using AES-128-ECB.
+
+    Args:
+        irk: 16-byte Identity Resolving Key.
+        address: BLE address string (e.g. 'AA:BB:CC:DD:EE:FF').
+
+    Returns:
+        True if the address resolves against the IRK.
+    """
+    try:
+        from cryptography.hazmat.primitives.ciphers import Cipher, algorithms, modes
+    except ImportError:
+        logger.error("cryptography package required for RPA resolution")
+        return False
+
+    # Parse address bytes (remove colons, convert to bytes)
+    addr_bytes = bytes.fromhex(address.replace(':', '').replace('-', ''))
+    if len(addr_bytes) != 6:
+        return False
+
+    # RPA: upper 2 bits of MSB must be 01 (resolvable)
+    if (addr_bytes[0] >> 6) != 1:
+        return False
+
+    # prand = upper 3 bytes (MSB first), hash = lower 3 bytes
+    prand = addr_bytes[0:3]
+    expected_hash = addr_bytes[3:6]
+
+    # ah(k, r) = e(k, r') mod 2^24
+    # r' is prand zero-padded to 16 bytes (MSB)
+    plaintext = b'\x00' * 13 + prand
+
+    cipher = Cipher(algorithms.AES(irk), modes.ECB())
+    encryptor = cipher.encryptor()
+    encrypted = encryptor.update(plaintext) + encryptor.finalize()
+
+    # Take last 3 bytes as hash
+    computed_hash = encrypted[13:16]
+
+    return computed_hash == expected_hash
+
+
+@dataclass
+class LocateTarget:
+    """Target device specification for locate session."""
+    mac_address: str | None = None
+    name_pattern: str | None = None
+    irk_hex: str | None = None
+    device_id: str | None = None
+    # Hand-off metadata from Bluetooth mode
+    known_name: str | None = None
+    known_manufacturer: str | None = None
+    last_known_rssi: int | None = None
+
+    def matches(self, device: BTDeviceAggregate) -> bool:
+        """Check if a device matches this target."""
+        # Match by device_id (exact)
+        if self.device_id and device.device_id == self.device_id:
+            return True
+
+        # Match by device_id address portion (without :address_type suffix)
+        if self.device_id and ':' in self.device_id:
+            target_addr_part = self.device_id.rsplit(':', 1)[0].upper()
+            dev_addr = (device.address or '').upper()
+            if target_addr_part and dev_addr == target_addr_part:
+                return True
+
+        # Match by MAC/address (case-insensitive, normalize separators)
+        if self.mac_address:
+            dev_addr = (device.address or '').upper().replace('-', ':')
+            target_addr = self.mac_address.upper().replace('-', ':')
+            if dev_addr == target_addr:
+                return True
+
+        # Match by RPA resolution
+        if self.irk_hex:
+            try:
+                irk = bytes.fromhex(self.irk_hex)
+                if len(irk) == 16 and device.address and resolve_rpa(irk, device.address):
+                    return True
+            except (ValueError, TypeError):
+                pass
+
+        # Match by name pattern
+        if self.name_pattern and device.name and self.name_pattern.lower() in device.name.lower():
+            return True
+
+        # Match by known_name from handoff (exact name match)
+        return bool(self.known_name and device.name and self.known_name.lower() == device.name.lower())
+
+    def to_dict(self) -> dict:
+        return {
+            'mac_address': self.mac_address,
+            'name_pattern': self.name_pattern,
+            'irk_hex': self.irk_hex,
+            'device_id': self.device_id,
+            'known_name': self.known_name,
+            'known_manufacturer': self.known_manufacturer,
+            'last_known_rssi': self.last_known_rssi,
+        }
+
+
+class DistanceEstimator:
+    """Estimate distance from RSSI using log-distance path loss model."""
+
+    # Reference RSSI at 1 meter (typical BLE)
+    RSSI_AT_1M = -59
+
+    def __init__(self, path_loss_exponent: float = 2.0, rssi_at_1m: int = -59):
+        self.n = path_loss_exponent
+        self.rssi_at_1m = rssi_at_1m
+
+    def estimate(self, rssi: int) -> float:
+        """Estimate distance in meters from RSSI."""
+        if rssi >= 0 or self.n <= 0:
+            return 0.0
+        return 10 ** ((self.rssi_at_1m - rssi) / (10 * self.n))
+
+    @staticmethod
+    def proximity_band(distance: float) -> str:
+        """Classify distance into proximity band."""
+        if distance <= 1.0:
+            return 'IMMEDIATE'
+        elif distance <= 5.0:
+            return 'NEAR'
+        else:
+            return 'FAR'
+
+
+@dataclass
+class DetectionPoint:
+    """A single GPS-tagged BLE detection."""
+    timestamp: str
+    rssi: int
+    rssi_ema: float
+    estimated_distance: float
+    proximity_band: str
+    lat: float | None = None
+    lon: float | None = None
+    gps_accuracy: float | None = None
+    rpa_resolved: bool = False
+
+    def to_dict(self) -> dict:
+        return {
+            'timestamp': self.timestamp,
+            'rssi': self.rssi,
+            'rssi_ema': round(self.rssi_ema, 1),
+            'estimated_distance': round(self.estimated_distance, 2),
+            'proximity_band': self.proximity_band,
+            'lat': self.lat,
+            'lon': self.lon,
+            'gps_accuracy': self.gps_accuracy,
+            'rpa_resolved': self.rpa_resolved,
+        }
+
+
+class LocateSession:
+    """Active locate session tracking a target device."""
+
+    def __init__(
+        self,
+        target: LocateTarget,
+        environment: Environment = Environment.OUTDOOR,
+        custom_exponent: float | None = None,
+        fallback_lat: float | None = None,
+        fallback_lon: float | None = None,
+    ):
+        self.target = target
+        self.environment = environment
+        self.fallback_lat = fallback_lat
+        self.fallback_lon = fallback_lon
+        self._lock = threading.Lock()
+
+        # Distance estimator
+        n = custom_exponent if environment == Environment.CUSTOM and custom_exponent else environment.value
+        self.estimator = DistanceEstimator(path_loss_exponent=n)
+
+        # Signal trail
+        self.trail: list[DetectionPoint] = []
+
+        # RSSI EMA state
+        self._rssi_ema: float | None = None
+
+        # SSE event queue
+        self.event_queue: queue.Queue = queue.Queue(maxsize=500)
+
+        # Session state
+        self.active = False
+        self.started_at: datetime | None = None
+        self.detection_count = 0
+        self.last_detection: datetime | None = None
+
+        # Debug counters
+        self.callback_call_count = 0
+        self.poll_count = 0
+        self._last_seen_device: str | None = None
+
+        # Scanner reference
+        self._scanner: BluetoothScanner | None = None
+        self._poll_thread: threading.Thread | None = None
+        self._stop_event = threading.Event()
+        # Track last RSSI per device to detect changes
+        self._last_cb_rssi: dict[str, int] = {}  # Dedup for rapid callbacks only
+
+    def start(self) -> bool:
+        """Start the locate session.
+
+        Subscribes to scanner callbacks AND runs a polling thread that
+        checks the aggregator directly (handles bleak scan timeout).
+        """
+        self._scanner = get_bluetooth_scanner()
+        self._scanner.add_device_callback(self._on_device)
+
+        # Ensure BLE scanning is active
+        if not self._scanner.is_scanning:
+            logger.info("BT scanner not running, starting scan for locate session")
+            self._scanner_started_by_us = True
+            if not self._scanner.start_scan(mode='auto'):
+                logger.warning("Failed to start BT scanner for locate session")
+        else:
+            self._scanner_started_by_us = False
+
+        self.active = True
+        self.started_at = datetime.now()
+        self._stop_event.clear()
+
+        # Start polling thread as reliable fallback
+        self._poll_thread = threading.Thread(
+            target=self._poll_loop, daemon=True, name='bt-locate-poll'
+        )
+        self._poll_thread.start()
+
+        logger.info(f"Locate session started for target: {self.target.to_dict()}")
+        return True
+
+    def stop(self) -> None:
+        """Stop the locate session."""
+        self.active = False
+        self._stop_event.set()
+        if self._scanner:
+            self._scanner.remove_device_callback(self._on_device)
+            if getattr(self, '_scanner_started_by_us', False) and self._scanner.is_scanning:
+                self._scanner.stop_scan()
+                logger.info("Stopped BT scanner (was started by locate session)")
+        if self._poll_thread:
+            self._poll_thread.join(timeout=3.0)
+        logger.info("Locate session stopped")
+
+    def _poll_loop(self) -> None:
+        """Poll scanner aggregator for target device updates."""
+        while not self._stop_event.is_set():
+            self._stop_event.wait(timeout=1.5)
+            if self._stop_event.is_set():
+                break
+            try:
+                self._check_aggregator()
+            except Exception as e:
+                logger.error(f"Locate poll error: {e}")
+
+    def _check_aggregator(self) -> None:
+        """Check the scanner's aggregator for the target device."""
+        if not self._scanner:
+            return
+
+        self.poll_count += 1
+
+        # Restart scan if it expired (bleak 10s timeout)
+        if not self._scanner.is_scanning:
+            logger.info("Scanner stopped, restarting for locate session")
+            self._scanner.start_scan(mode='auto')
+
+        # Check devices seen within a recent window.  Using a short window
+        # (rather than the aggregator's full 120s) so that once a device
+        # goes silent its stale RSSI stops producing detections.  The window
+        # must survive bleak's 10s scan cycle + restart gap (~3s).
+        devices = self._scanner.get_devices(max_age_seconds=15)
+        found_target = False
+        for device in devices:
+            if not self.target.matches(device):
+                continue
+            found_target = True
+            rssi = device.rssi_current
+            if rssi is None:
+                continue
+            self._record_detection(device, rssi)
+            break  # One match per poll cycle is sufficient
+
+        # Log periodically for debugging
+        if self.poll_count % 20 == 0 or (self.poll_count <= 5) or not found_target:
+            logger.info(
+                f"Poll #{self.poll_count}: {len(devices)} devices, "
+                f"target_found={found_target}, "
+                f"detections={self.detection_count}, "
+                f"scanning={self._scanner.is_scanning}"
+            )
+
+    def _on_device(self, device: BTDeviceAggregate) -> None:
+        """Scanner callback: check if device matches target."""
+        if not self.active:
+            return
+
+        self.callback_call_count += 1
+        self._last_seen_device = f"{device.device_id}|{device.name}"
+
+        if not self.target.matches(device):
+            return
+
+        rssi = device.rssi_current
+        if rssi is None:
+            return
+
+        # Dedup rapid callbacks (bleak can fire many times per second)
+        prev = self._last_cb_rssi.get(device.device_id)
+        if prev == rssi:
+            return
+        self._last_cb_rssi[device.device_id] = rssi
+        self._record_detection(device, rssi)
+
+    def _record_detection(self, device: BTDeviceAggregate, rssi: int) -> None:
+        """Record a target detection with GPS tagging."""
+        logger.info(f"Target detected: {device.address} RSSI={rssi} name={device.name}")
+
+        # Update EMA
+        if self._rssi_ema is None:
+            self._rssi_ema = float(rssi)
+        else:
+            self._rssi_ema = EMA_ALPHA * rssi + (1 - EMA_ALPHA) * self._rssi_ema
+
+        # Estimate distance
+        distance = self.estimator.estimate(rssi)
+        band = DistanceEstimator.proximity_band(distance)
+
+        # Check RPA resolution
+        rpa_resolved = False
+        if self.target.irk_hex and device.address:
+            try:
+                irk = bytes.fromhex(self.target.irk_hex)
+                rpa_resolved = resolve_rpa(irk, device.address)
+            except (ValueError, TypeError):
+                pass
+
+        # GPS tag — prefer live GPS, fall back to user-set coordinates
+        gps_pos = get_current_position()
+        lat = gps_pos.latitude if gps_pos else None
+        lon = gps_pos.longitude if gps_pos else None
+        gps_acc = None
+        if gps_pos:
+            epx = gps_pos.epx or 0
+            epy = gps_pos.epy or 0
+            if epx or epy:
+                gps_acc = round(max(epx, epy), 1)
+        elif self.fallback_lat is not None and self.fallback_lon is not None:
+            lat = self.fallback_lat
+            lon = self.fallback_lon
+
+        now = datetime.now()
+        point = DetectionPoint(
+            timestamp=now.isoformat(),
+            rssi=rssi,
+            rssi_ema=self._rssi_ema,
+            estimated_distance=distance,
+            proximity_band=band,
+            lat=lat,
+            lon=lon,
+            gps_accuracy=gps_acc,
+            rpa_resolved=rpa_resolved,
+        )
+
+        with self._lock:
+            self.trail.append(point)
+            if len(self.trail) > MAX_TRAIL_POINTS:
+                self.trail = self.trail[-MAX_TRAIL_POINTS:]
+            self.detection_count += 1
+            self.last_detection = now
+
+        # Queue SSE event
+        event = {
+            'type': 'detection',
+            'data': point.to_dict(),
+            'device_name': device.name,
+            'device_address': device.address,
+        }
+        try:
+            self.event_queue.put_nowait(event)
+        except queue.Full:
+            try:
+                self.event_queue.get_nowait()
+                self.event_queue.put_nowait(event)
+            except queue.Empty:
+                pass
+
+    def get_trail(self) -> list[dict]:
+        """Get the full detection trail."""
+        with self._lock:
+            return [p.to_dict() for p in self.trail]
+
+    def get_gps_trail(self) -> list[dict]:
+        """Get only trail points that have GPS coordinates."""
+        with self._lock:
+            return [p.to_dict() for p in self.trail if p.lat is not None]
+
+    def get_status(self) -> dict:
+        """Get session status."""
+        gps_pos = get_current_position()
+
+        # Collect scanner/aggregator data OUTSIDE self._lock to avoid ABBA
+        # deadlock: get_status would hold self._lock then wait on
+        # aggregator._lock, while _poll_loop holds aggregator._lock then
+        # waits on self._lock in _record_detection.
+        debug_devices = self._debug_device_sample()
+        scanner_running = self._scanner.is_scanning if self._scanner else False
+        scanner_device_count = self._scanner.device_count if self._scanner else 0
+        callback_registered = (
+            self._on_device in self._scanner._on_device_updated_callbacks
+            if self._scanner else False
+        )
+
+        with self._lock:
+            return {
+                'active': self.active,
+                'target': self.target.to_dict(),
+                'environment': self.environment.name,
+                'path_loss_exponent': self.estimator.n,
+                'started_at': self.started_at.isoformat() if self.started_at else None,
+                'detection_count': self.detection_count,
+                'gps_trail_count': sum(1 for p in self.trail if p.lat is not None),
+                'last_detection': self.last_detection.isoformat() if self.last_detection else None,
+                'scanner_running': scanner_running,
+                'scanner_device_count': scanner_device_count,
+                'callback_registered': callback_registered,
+                'event_queue_size': self.event_queue.qsize(),
+                'callback_call_count': self.callback_call_count,
+                'poll_count': self.poll_count,
+                'poll_thread_alive': self._poll_thread.is_alive() if self._poll_thread else False,
+                'last_seen_device': self._last_seen_device,
+                'gps_available': gps_pos is not None,
+                'gps_source': 'live' if gps_pos else (
+                    'manual' if self.fallback_lat is not None else 'none'
+                ),
+                'fallback_lat': self.fallback_lat,
+                'fallback_lon': self.fallback_lon,
+                'latest_rssi': self.trail[-1].rssi if self.trail else None,
+                'latest_rssi_ema': round(self.trail[-1].rssi_ema, 1) if self.trail else None,
+                'latest_distance': round(self.trail[-1].estimated_distance, 2) if self.trail else None,
+                'latest_band': self.trail[-1].proximity_band if self.trail else None,
+                'debug_devices': debug_devices,
+            }
+
+    def set_environment(self, environment: Environment, custom_exponent: float | None = None) -> None:
+        """Update the environment and recalculate distance estimator."""
+        with self._lock:
+            self.environment = environment
+            n = custom_exponent if environment == Environment.CUSTOM and custom_exponent else environment.value
+            self.estimator = DistanceEstimator(path_loss_exponent=n)
+
+    def _debug_device_sample(self) -> list[dict]:
+        """Return a sample of scanner devices for debugging matching issues."""
+        if not self._scanner:
+            return []
+        try:
+            devices = self._scanner.get_devices(max_age_seconds=30)
+            return [
+                {
+                    'id': d.device_id,
+                    'addr': d.address,
+                    'name': d.name,
+                    'rssi': d.rssi_current,
+                    'match': self.target.matches(d),
+                }
+                for d in devices[:8]
+            ]
+        except Exception:
+            return []
+
+    def clear_trail(self) -> None:
+        """Clear the detection trail."""
+        with self._lock:
+            self.trail.clear()
+            self.detection_count = 0
+
+
+# Module-level session management (single active session)
+_session: LocateSession | None = None
+_session_lock = threading.Lock()
+
+
+def start_locate_session(
+    target: LocateTarget,
+    environment: Environment = Environment.OUTDOOR,
+    custom_exponent: float | None = None,
+    fallback_lat: float | None = None,
+    fallback_lon: float | None = None,
+) -> LocateSession:
+    """Start a new locate session, stopping any existing one."""
+    global _session
+
+    with _session_lock:
+        if _session and _session.active:
+            _session.stop()
+
+        _session = LocateSession(
+            target, environment, custom_exponent, fallback_lat, fallback_lon
+        )
+        _session.start()
+        return _session
+
+
+def stop_locate_session() -> None:
+    """Stop the active locate session."""
+    global _session
+
+    with _session_lock:
+        if _session:
+            _session.stop()
+            _session = None
+
+
+def get_locate_session() -> LocateSession | None:
+    """Get the current locate session (if any)."""
+    with _session_lock:
+        return _session

utils/database.py

@@ -531,6 +531,30 @@ def init_db() -> None:
             ON push_payloads(agent_id, received_at)
         ''')
 
+        # Tracked satellites table for persistent satellite management
+        conn.execute('''
+            CREATE TABLE IF NOT EXISTS tracked_satellites (
+                id INTEGER PRIMARY KEY AUTOINCREMENT,
+                norad_id TEXT UNIQUE NOT NULL,
+                name TEXT NOT NULL,
+                tle_line1 TEXT,
+                tle_line2 TEXT,
+                enabled BOOLEAN DEFAULT 1,
+                builtin BOOLEAN DEFAULT 0,
+                added_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+            )
+        ''')
+
+        # Seed builtin satellites if not already present
+        conn.execute('''
+            INSERT OR IGNORE INTO tracked_satellites (norad_id, name, tle_line1, tle_line2, enabled, builtin)
+            VALUES ('25544', 'ISS (ZARYA)', NULL, NULL, 1, 1)
+        ''')
+        conn.execute('''
+            INSERT OR IGNORE INTO tracked_satellites (norad_id, name, tle_line1, tle_line2, enabled, builtin)
+            VALUES ('40069', 'METEOR-M2', NULL, NULL, 1, 1)
+        ''')
+
         logger.info("Database initialized successfully")
 
 
@@ -2170,3 +2194,111 @@ def cleanup_old_payloads(max_age_hours: int = 24) -> int:
         ''', (f'-{max_age_hours} hours',))
         return cursor.rowcount
 
+
+# =============================================================================
+# Tracked Satellites Functions
+# =============================================================================
+
+def get_tracked_satellites(enabled_only: bool = False) -> list[dict]:
+    """Return all tracked satellites, optionally filtered to enabled only."""
+    with get_db() as conn:
+        if enabled_only:
+            rows = conn.execute(
+                'SELECT norad_id, name, tle_line1, tle_line2, enabled, builtin, added_at '
+                'FROM tracked_satellites WHERE enabled = 1 ORDER BY builtin DESC, name'
+            ).fetchall()
+        else:
+            rows = conn.execute(
+                'SELECT norad_id, name, tle_line1, tle_line2, enabled, builtin, added_at '
+                'FROM tracked_satellites ORDER BY builtin DESC, name'
+            ).fetchall()
+        return [
+            {
+                'norad_id': r[0],
+                'name': r[1],
+                'tle_line1': r[2],
+                'tle_line2': r[3],
+                'enabled': bool(r[4]),
+                'builtin': bool(r[5]),
+                'added_at': r[6],
+            }
+            for r in rows
+        ]
+
+
+def add_tracked_satellite(
+    norad_id: str,
+    name: str,
+    tle_line1: str | None = None,
+    tle_line2: str | None = None,
+    enabled: bool = True,
+    builtin: bool = False,
+) -> bool:
+    """Insert a tracked satellite. Returns True if inserted, False if duplicate."""
+    with get_db() as conn:
+        try:
+            conn.execute(
+                'INSERT OR IGNORE INTO tracked_satellites '
+                '(norad_id, name, tle_line1, tle_line2, enabled, builtin) '
+                'VALUES (?, ?, ?, ?, ?, ?)',
+                (str(norad_id), name, tle_line1, tle_line2, int(enabled), int(builtin)),
+            )
+            return conn.total_changes > 0
+        except sqlite3.Error as e:
+            logger.error(f"Error adding tracked satellite {norad_id}: {e}")
+            return False
+
+
+def bulk_add_tracked_satellites(satellites_list: list[dict]) -> int:
+    """Insert many tracked satellites at once. Returns count of newly inserted."""
+    added = 0
+    with get_db() as conn:
+        for sat in satellites_list:
+            try:
+                cursor = conn.execute(
+                    'INSERT OR IGNORE INTO tracked_satellites '
+                    '(norad_id, name, tle_line1, tle_line2, enabled, builtin) '
+                    'VALUES (?, ?, ?, ?, ?, ?)',
+                    (
+                        str(sat['norad_id']),
+                        sat['name'],
+                        sat.get('tle_line1'),
+                        sat.get('tle_line2'),
+                        int(sat.get('enabled', True)),
+                        int(sat.get('builtin', False)),
+                    ),
+                )
+                if cursor.rowcount > 0:
+                    added += 1
+            except (sqlite3.Error, KeyError) as e:
+                logger.warning(f"Error bulk-adding satellite: {e}")
+    return added
+
+
+def update_tracked_satellite(norad_id: str, enabled: bool) -> bool:
+    """Toggle enabled state for a tracked satellite."""
+    with get_db() as conn:
+        cursor = conn.execute(
+            'UPDATE tracked_satellites SET enabled = ? WHERE norad_id = ?',
+            (int(enabled), str(norad_id)),
+        )
+        return cursor.rowcount > 0
+
+
+def remove_tracked_satellite(norad_id: str) -> tuple[bool, str]:
+    """Delete a tracked satellite by NORAD ID. Refuses to delete builtins."""
+    with get_db() as conn:
+        row = conn.execute(
+            'SELECT builtin FROM tracked_satellites WHERE norad_id = ?',
+            (str(norad_id),),
+        ).fetchone()
+        if row is None:
+            return False, 'Satellite not found'
+        if row[0]:
+            return False, 'Cannot remove builtin satellite'
+        conn.execute(
+            'DELETE FROM tracked_satellites WHERE norad_id = ?',
+            (str(norad_id),),
+        )
+        return True, 'Removed'
+

utils/dsc/decoder.py

@@ -264,6 +264,20 @@ class DSCDecoder:
                 symbol_value = self._bits_to_symbol(symbol_bits)
                 symbols.append(symbol_value)
 
+        # Strip phasing sequence (RX/DX symbols 120-126) from the
+        # start of the message. Per ITU-R M.493, after the dot pattern
+        # there are 7 phasing symbols before the format specifier.
+        msg_start = 0
+        for i, sym in enumerate(symbols):
+            if 120 <= sym <= 126:
+                msg_start = i + 1
+            else:
+                break
+        symbols = symbols[msg_start:]
+
+        if len(symbols) < 5:
+            return None
+
         # Look for EOS (End of Sequence) - symbol 127
         eos_found = False
         eos_index = -1
@@ -404,9 +418,10 @@ class DSCDecoder:
             digits.append(f'{sym:02d}')
 
         mmsi = ''.join(digits)
-        # MMSI is 9 digits, might need to trim leading zero
+        # MMSI is 9 digits - trim the leading digit from the 10-digit
+        # BCD result since the first symbol's high digit is always 0
         if len(mmsi) > 9:
-            mmsi = mmsi[-9:]
+            mmsi = mmsi[1:]
 
         return mmsi.zfill(9)
 

utils/gps.py

@@ -6,28 +6,86 @@ Provides GPS location data by connecting to the gpsd daemon.
 
 from __future__ import annotations
 
+import contextlib
 import logging
+import socket as _socket_mod
 import threading
-import time
+from dataclasses import dataclass, field
-from dataclasses import dataclass
 from datetime import datetime
-from typing import Optional, Callable
+from typing import Callable
 
 logger = logging.getLogger('intercept.gps')
 
 
+@dataclass
+class GPSSatellite:
+    """Individual satellite data from gpsd SKY message."""
+    prn: int
+    elevation: float | None = None  # degrees
+    azimuth: float | None = None  # degrees
+    snr: float | None = None  # dB-Hz
+    used: bool = False
+    constellation: str = 'GPS'  # GPS, GLONASS, Galileo, BeiDou, SBAS, QZSS
+
+    def to_dict(self) -> dict:
+        return {
+            'prn': self.prn,
+            'elevation': self.elevation,
+            'azimuth': self.azimuth,
+            'snr': self.snr,
+            'used': self.used,
+            'constellation': self.constellation,
+        }
+
+
+@dataclass
+class GPSSkyData:
+    """Sky view data from gpsd SKY message."""
+    satellites: list[GPSSatellite] = field(default_factory=list)
+    hdop: float | None = None
+    vdop: float | None = None
+    pdop: float | None = None
+    tdop: float | None = None
+    gdop: float | None = None
+    xdop: float | None = None
+    ydop: float | None = None
+    nsat: int = 0  # total visible
+    usat: int = 0  # total used
+
+    def to_dict(self) -> dict:
+        return {
+            'satellites': [s.to_dict() for s in self.satellites],
+            'hdop': self.hdop,
+            'vdop': self.vdop,
+            'pdop': self.pdop,
+            'tdop': self.tdop,
+            'gdop': self.gdop,
+            'xdop': self.xdop,
+            'ydop': self.ydop,
+            'nsat': self.nsat,
+            'usat': self.usat,
+        }
+
+
 @dataclass
 class GPSPosition:
     """GPS position data."""
     latitude: float
     longitude: float
-    altitude: Optional[float] = None
+    altitude: float | None = None
-    speed: Optional[float] = None  # m/s
+    speed: float | None = None  # m/s
-    heading: Optional[float] = None  # degrees
+    heading: float | None = None  # degrees
-    satellites: Optional[int] = None
+    climb: float | None = None  # m/s vertical speed
+    satellites: int | None = None
     fix_quality: int = 0  # 0=unknown, 1=no fix, 2=2D fix, 3=3D fix
-    timestamp: Optional[datetime] = None
+    timestamp: datetime | None = None
-    device: Optional[str] = None
+    device: str | None = None
+    # Error estimates
+    epx: float | None = None  # lon error (m)
+    epy: float | None = None  # lat error (m)
+    epv: float | None = None  # vertical error (m)
+    eps: float | None = None  # speed error (m/s)
+    ept: float | None = None  # time error (s)
 
     def to_dict(self) -> dict:
         """Convert to dictionary for JSON serialization."""
@@ -37,13 +95,45 @@ class GPSPosition:
             'altitude': self.altitude,
             'speed': self.speed,
             'heading': self.heading,
+            'climb': self.climb,
             'satellites': self.satellites,
             'fix_quality': self.fix_quality,
             'timestamp': self.timestamp.isoformat() if self.timestamp else None,
             'device': self.device,
+            'epx': self.epx,
+            'epy': self.epy,
+            'epv': self.epv,
+            'eps': self.eps,
+            'ept': self.ept,
         }
 
 
+def _classify_constellation(prn: int, gnssid: int | None = None) -> str:
+    """Classify satellite constellation from PRN or gnssid."""
+    if gnssid is not None:
+        mapping = {
+            0: 'GPS', 1: 'SBAS', 2: 'Galileo', 3: 'BeiDou',
+            4: 'IMES', 5: 'QZSS', 6: 'GLONASS', 7: 'NavIC',
+        }
+        return mapping.get(gnssid, 'GPS')
+    # Fall back to PRN range heuristic
+    if 1 <= prn <= 32:
+        return 'GPS'
+    elif 33 <= prn <= 64:
+        return 'SBAS'
+    elif 65 <= prn <= 96:
+        return 'GLONASS'
+    elif 120 <= prn <= 158:
+        return 'SBAS'
+    elif 201 <= prn <= 264:
+        return 'BeiDou'
+    elif 301 <= prn <= 336:
+        return 'Galileo'
+    elif 193 <= prn <= 200:
+        return 'QZSS'
+    return 'GPS'
+
+
 class GPSDClient:
     """
     Connects to gpsd daemon for GPS data.
@@ -58,35 +148,43 @@ class GPSDClient:
     def __init__(self, host: str = DEFAULT_HOST, port: int = DEFAULT_PORT):
         self.host = host
         self.port = port
-        self._position: Optional[GPSPosition] = None
+        self._position: GPSPosition | None = None
+        self._sky: GPSSkyData | None = None
         self._lock = threading.Lock()
         self._running = False
-        self._thread: Optional[threading.Thread] = None
+        self._thread: threading.Thread | None = None
-        self._socket: Optional['socket.socket'] = None
+        self._socket: _socket_mod.socket | None = None
-        self._last_update: Optional[datetime] = None
+        self._last_update: datetime | None = None
-        self._error: Optional[str] = None
+        self._error: str | None = None
         self._callbacks: list[Callable[[GPSPosition], None]] = []
-        self._device: Optional[str] = None
+        self._sky_callbacks: list[Callable[[GPSSkyData], None]] = []
+        self._device: str | None = None
 
     @property
-    def position(self) -> Optional[GPSPosition]:
+    def position(self) -> GPSPosition | None:
         """Get the current GPS position."""
         with self._lock:
             return self._position
 
+    @property
+    def sky(self) -> GPSSkyData | None:
+        """Get the current sky view data."""
+        with self._lock:
+            return self._sky
+
     @property
     def is_running(self) -> bool:
         """Check if the client is running."""
         return self._running
 
     @property
-    def last_update(self) -> Optional[datetime]:
+    def last_update(self) -> datetime | None:
         """Get the time of the last position update."""
         with self._lock:
             return self._last_update
 
     @property
-    def error(self) -> Optional[str]:
+    def error(self) -> str | None:
         """Get any error message."""
         with self._lock:
             return self._error
@@ -105,6 +203,15 @@ class GPSDClient:
         if callback in self._callbacks:
             self._callbacks.remove(callback)
 
+    def add_sky_callback(self, callback: Callable[[GPSSkyData], None]) -> None:
+        """Add a callback to be called on sky data updates."""
+        self._sky_callbacks.append(callback)
+
+    def remove_sky_callback(self, callback: Callable[[GPSSkyData], None]) -> None:
+        """Remove a sky data update callback."""
+        if callback in self._sky_callbacks:
+            self._sky_callbacks.remove(callback)
+
     def start(self) -> bool:
         """Start receiving GPS data from gpsd."""
         import socket
@@ -135,10 +242,8 @@ class GPSDClient:
             self._error = str(e)
             logger.error(f"Failed to connect to gpsd at {self.host}:{self.port}: {e}")
             if self._socket:
-                try:
+                with contextlib.suppress(Exception):
                     self._socket.close()
-                except Exception:
-                    pass
                 self._socket = None
             return False
 
@@ -169,7 +274,7 @@ class GPSDClient:
         buffer = ""
         message_count = 0
 
-        print(f"[GPS] gpsd read loop started", flush=True)
+        print("[GPS] gpsd read loop started", flush=True)
 
         while self._running and self._socket:
             try:
@@ -202,6 +307,8 @@ class GPSDClient:
 
                         if msg_class == 'TPV':
                             self._handle_tpv(msg)
+                        elif msg_class == 'SKY':
+                            self._handle_sky(msg)
                         elif msg_class == 'DEVICES':
                             # Track connected device
                             devices = msg.get('devices', [])
@@ -239,11 +346,9 @@ class GPSDClient:
         timestamp = None
         time_str = msg.get('time')
         if time_str:
-            try:
+            with contextlib.suppress(ValueError, AttributeError):
                 # gpsd uses ISO format: 2024-01-01T12:00:00.000Z
                 timestamp = datetime.fromisoformat(time_str.replace('Z', '+00:00'))
-            except (ValueError, AttributeError):
-                pass
 
         position = GPSPosition(
             latitude=lat,
@@ -251,14 +356,58 @@ class GPSDClient:
             altitude=msg.get('alt'),
             speed=msg.get('speed'),  # m/s in gpsd
             heading=msg.get('track'),
+            climb=msg.get('climb'),
             fix_quality=mode,
             timestamp=timestamp,
             device=self._device or f"gpsd://{self.host}:{self.port}",
+            epx=msg.get('epx'),
+            epy=msg.get('epy'),
+            epv=msg.get('epv'),
+            eps=msg.get('eps'),
+            ept=msg.get('ept'),
         )
 
         print(f"[GPS] gpsd FIX: {lat:.6f}, {lon:.6f} (mode: {mode})", flush=True)
         self._update_position(position)
 
+    def _handle_sky(self, msg: dict) -> None:
+        """Handle SKY (satellite sky view) message from gpsd."""
+        sats = []
+        for sat in msg.get('satellites', []):
+            prn = sat.get('PRN', 0)
+            gnssid = sat.get('gnssid')
+            sats.append(GPSSatellite(
+                prn=prn,
+                elevation=sat.get('el'),
+                azimuth=sat.get('az'),
+                snr=sat.get('ss'),
+                used=sat.get('used', False),
+                constellation=_classify_constellation(prn, gnssid),
+            ))
+
+        sky_data = GPSSkyData(
+            satellites=sats,
+            hdop=msg.get('hdop'),
+            vdop=msg.get('vdop'),
+            pdop=msg.get('pdop'),
+            tdop=msg.get('tdop'),
+            gdop=msg.get('gdop'),
+            xdop=msg.get('xdop'),
+            ydop=msg.get('ydop'),
+            nsat=len(sats),
+            usat=sum(1 for s in sats if s.used),
+        )
+
+        with self._lock:
+            self._sky = sky_data
+
+        # Notify sky callbacks
+        for callback in self._sky_callbacks:
+            try:
+                callback(sky_data)
+            except Exception as e:
+                logger.error(f"GPS sky callback error: {e}")
+
     def _update_position(self, position: GPSPosition) -> None:
         """Update the current position and notify callbacks."""
         with self._lock:
@@ -275,18 +424,19 @@ class GPSDClient:
 
 
 # Global GPS client instance
-_gps_client: Optional[GPSDClient] = None
+_gps_client: GPSDClient | None = None
 _gps_lock = threading.Lock()
 
 
-def get_gps_reader() -> Optional[GPSDClient]:
+def get_gps_reader() -> GPSDClient | None:
     """Get the global GPS client instance."""
     with _gps_lock:
         return _gps_client
 
 
 def start_gpsd(host: str = 'localhost', port: int = 2947,
-               callback: Optional[Callable[[GPSPosition], None]] = None) -> bool:
+               callback: Callable[[GPSPosition], None] | None = None,
+               sky_callback: Callable[[GPSSkyData], None] | None = None) -> bool:
     """
     Start the global GPS client connected to gpsd.
 
@@ -294,6 +444,7 @@ def start_gpsd(host: str = 'localhost', port: int = 2947,
         host: gpsd host (default localhost)
         port: gpsd port (default 2947)
         callback: Optional callback for position updates
+        sky_callback: Optional callback for sky data updates
 
     Returns:
         True if started successfully
@@ -307,9 +458,11 @@ def start_gpsd(host: str = 'localhost', port: int = 2947,
 
         _gps_client = GPSDClient(host, port)
 
-        # Register callback BEFORE starting to avoid race condition
+        # Register callbacks BEFORE starting to avoid race condition
         if callback:
             _gps_client.add_callback(callback)
+        if sky_callback:
+            _gps_client.add_sky_callback(sky_callback)
 
         return _gps_client.start()
 
@@ -324,9 +477,187 @@ def stop_gps() -> None:
             _gps_client = None
 
 
-def get_current_position() -> Optional[GPSPosition]:
+def get_current_position() -> GPSPosition | None:
     """Get the current GPS position from the global client."""
     client = get_gps_reader()
     if client:
         return client.position
     return None
+
+
+# ============================================
+# GPS device detection and gpsd auto-start
+# ============================================
+
+_gpsd_process: 'subprocess.Popen | None' = None
+_gpsd_process_lock = threading.Lock()
+
+
+def detect_gps_devices() -> list[dict]:
+    """
+    Detect connected GPS serial devices.
+
+    Returns list of dicts with 'path' and 'description' keys.
+    """
+    import glob
+    import os
+    import platform
+
+    devices: list[dict] = []
+    system = platform.system()
+
+    if system == 'Linux':
+        # Common USB GPS device paths
+        patterns = ['/dev/ttyUSB*', '/dev/ttyACM*']
+        for pattern in patterns:
+            for path in sorted(glob.glob(pattern)):
+                desc = _describe_device_linux(path)
+                devices.append({'path': path, 'description': desc})
+
+        # Also check /dev/serial/by-id for descriptive names
+        serial_dir = '/dev/serial/by-id'
+        if os.path.isdir(serial_dir):
+            for name in sorted(os.listdir(serial_dir)):
+                full = os.path.join(serial_dir, name)
+                real = os.path.realpath(full)
+                # Skip if we already found this device
+                if any(d['path'] == real for d in devices):
+                    # Update description with the more descriptive name
+                    for d in devices:
+                        if d['path'] == real:
+                            d['description'] = name
+                    continue
+                devices.append({'path': real, 'description': name})
+
+    elif system == 'Darwin':
+        # macOS: USB serial devices (prefer cu. over tty. for outgoing)
+        patterns = ['/dev/cu.usbmodem*', '/dev/cu.usbserial*']
+        for pattern in patterns:
+            for path in sorted(glob.glob(pattern)):
+                desc = _describe_device_macos(path)
+                devices.append({'path': path, 'description': desc})
+
+    # Sort: devices with GPS-related descriptions first
+    gps_keywords = ('gps', 'gnss', 'u-blox', 'ublox', 'nmea', 'sirf', 'navigation')
+    devices.sort(key=lambda d: (
+        0 if any(k in d['description'].lower() for k in gps_keywords) else 1
+    ))
+
+    return devices
+
+
+def _describe_device_linux(path: str) -> str:
+    """Get a human-readable description of a Linux serial device."""
+    import os
+    basename = os.path.basename(path)
+    # Try to read from sysfs
+    try:
+        # /sys/class/tty/ttyUSB0/device/../product
+        sysfs = f'/sys/class/tty/{basename}/device/../product'
+        if os.path.exists(sysfs):
+            with open(sysfs) as f:
+                return f.read().strip()
+    except Exception:
+        pass
+    return basename
+
+
+def _describe_device_macos(path: str) -> str:
+    """Get a description of a macOS serial device."""
+    import os
+    return os.path.basename(path)
+
+
+def is_gpsd_running(host: str = 'localhost', port: int = 2947) -> bool:
+    """Check if gpsd is reachable."""
+    import socket
+    try:
+        sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+        sock.settimeout(1.0)
+        sock.connect((host, port))
+        sock.close()
+        return True
+    except Exception:
+        return False
+
+
+def start_gpsd_daemon(device_path: str, host: str = 'localhost',
+                      port: int = 2947) -> tuple[bool, str]:
+    """
+    Start gpsd daemon pointing at the given device.
+
+    Returns (success, message) tuple.
+    """
+    import shutil
+    import subprocess
+
+    global _gpsd_process
+
+    with _gpsd_process_lock:
+        # Already running?
+        if is_gpsd_running(host, port):
+            return True, 'gpsd already running'
+
+        gpsd_bin = shutil.which('gpsd')
+        if not gpsd_bin:
+            return False, 'gpsd not installed'
+
+        # Stop any existing managed process
+        stop_gpsd_daemon()
+
+        try:
+            import os
+            if not os.path.exists(device_path):
+                return False, f'Device {device_path} not found'
+
+            cmd = [gpsd_bin, '-N', '-n', '-S', str(port), device_path]
+            logger.info(f"Starting gpsd: {' '.join(cmd)}")
+            print(f"[GPS] Starting gpsd: {' '.join(cmd)}", flush=True)
+
+            _gpsd_process = subprocess.Popen(
+                cmd,
+                stdout=subprocess.DEVNULL,
+                stderr=subprocess.PIPE,
+            )
+
+            # Give gpsd a moment to start
+            import time
+            time.sleep(1.5)
+
+            if _gpsd_process.poll() is not None:
+                stderr = ''
+                if _gpsd_process.stderr:
+                    stderr = _gpsd_process.stderr.read().decode('utf-8', errors='ignore').strip()
+                msg = f'gpsd exited with code {_gpsd_process.returncode}'
+                if stderr:
+                    msg += f': {stderr}'
+                return False, msg
+
+            # Verify it's listening
+            if is_gpsd_running(host, port):
+                return True, f'gpsd started on {device_path}'
+            else:
+                return False, 'gpsd started but not accepting connections'
+
+        except Exception as e:
+            logger.error(f"Failed to start gpsd: {e}")
+            return False, str(e)
+
+
+def stop_gpsd_daemon() -> None:
+    """Stop the managed gpsd daemon process."""
+    global _gpsd_process
+
+    with _gpsd_process_lock:
+        if _gpsd_process and _gpsd_process.poll() is None:
+            try:
+                _gpsd_process.terminate()
+                _gpsd_process.wait(timeout=3.0)
+            except Exception:
+                try:
+                    _gpsd_process.kill()
+                except Exception:
+                    pass
+            logger.info("Stopped gpsd daemon")
+            print("[GPS] Stopped gpsd daemon", flush=True)
+        _gpsd_process = None

utils/process.py

@@ -2,11 +2,14 @@ from __future__ import annotations
 
 import atexit
 import logging
+import os
+import platform
 import signal
 import subprocess
 import re
 import threading
 import time
+from pathlib import Path
 from typing import Any, Callable
 
 from .dependencies import check_tool
@@ -117,6 +120,93 @@ def cleanup_stale_processes() -> None:
             pass
 
 
+_DUMP1090_PID_FILE = Path(__file__).resolve().parent.parent / 'instance' / 'dump1090.pid'
+
+
+def write_dump1090_pid(pid: int) -> None:
+    """Write the PID of an app-spawned dump1090 process to a PID file."""
+    try:
+        _DUMP1090_PID_FILE.parent.mkdir(parents=True, exist_ok=True)
+        _DUMP1090_PID_FILE.write_text(str(pid))
+        logger.debug(f"Wrote dump1090 PID file: {pid}")
+    except OSError as e:
+        logger.warning(f"Failed to write dump1090 PID file: {e}")
+
+
+def clear_dump1090_pid() -> None:
+    """Remove the dump1090 PID file."""
+    try:
+        _DUMP1090_PID_FILE.unlink(missing_ok=True)
+        logger.debug("Cleared dump1090 PID file")
+    except OSError as e:
+        logger.warning(f"Failed to clear dump1090 PID file: {e}")
+
+
+def _is_dump1090_process(pid: int) -> bool:
+    """Check if the given PID is actually a dump1090/readsb process."""
+    try:
+        if platform.system() == 'Linux':
+            cmdline_path = Path(f'/proc/{pid}/cmdline')
+            if cmdline_path.exists():
+                cmdline = cmdline_path.read_bytes().replace(b'\x00', b' ').decode('utf-8', errors='ignore')
+                return 'dump1090' in cmdline or 'readsb' in cmdline
+        # macOS or fallback
+        result = subprocess.run(
+            ['ps', '-p', str(pid), '-o', 'comm='],
+            capture_output=True, text=True, timeout=5
+        )
+        comm = result.stdout.strip()
+        return 'dump1090' in comm or 'readsb' in comm
+    except Exception:
+        return False
+
+
+def cleanup_stale_dump1090() -> None:
+    """Kill a stale app-spawned dump1090 using the PID file.
+
+    Safe no-op if no PID file exists, process is dead, or PID was reused
+    by another program.
+    """
+    if not _DUMP1090_PID_FILE.exists():
+        return
+
+    try:
+        pid = int(_DUMP1090_PID_FILE.read_text().strip())
+    except (ValueError, OSError) as e:
+        logger.warning(f"Invalid dump1090 PID file: {e}")
+        clear_dump1090_pid()
+        return
+
+    # Verify this PID is still a dump1090/readsb process
+    if not _is_dump1090_process(pid):
+        logger.debug(f"PID {pid} is not dump1090/readsb (dead or reused), removing stale PID file")
+        clear_dump1090_pid()
+        return
+
+    # Kill the process group
+    logger.info(f"Killing stale app-spawned dump1090 (PID {pid})")
+    try:
+        pgid = os.getpgid(pid)
+        os.killpg(pgid, signal.SIGTERM)
+        # Brief wait for graceful shutdown
+        for _ in range(10):
+            try:
+                os.kill(pid, 0)  # Check if still alive
+                time.sleep(0.2)
+            except OSError:
+                break
+        else:
+            # Still alive, force kill
+            try:
+                os.killpg(pgid, signal.SIGKILL)
+            except OSError:
+                pass
+    except OSError as e:
+        logger.debug(f"Error killing stale dump1090 PID {pid}: {e}")
+
+    clear_dump1090_pid()
+
+
 def is_valid_mac(mac: str | None) -> bool:
     """Validate MAC address format."""
     if not mac: