AetherLink-SDR-MCP: Software Defined Radio Model Context Protocol Server

Control Software Defined Radios and decode radio protocols through an AI-friendly Model Context Protocol interface.

🚀 Features

• Protocol Decoders: ADS-B aircraft tracking, POCSAG pagers, AIS ship tracking, Meteor-M LRPT satellites, ISM band devices

• Weather Satellites: Meteor-M2-3/M2-4 LRPT decoding with SatDump (NOAA APT deprecated - decommissioned Aug 2025)

• Advanced Analysis: Real-time spectrum analysis, waterfall displays, signal detection, frequency scanning

• Audio Recording: Demodulate and record FM/AM audio as WAV files

• ISM Band Scanning: Decode 433MHz/315MHz devices (weather stations, sensors, doorbells, tire pressure monitors)

• MCP Integration: Seamless integration with Claude Desktop and other MCP clients

• 27 MCP Tools: Complete SDR control through natural language

Related MCP server: MCP Hardware Access Library

📦 Installation

Prerequisites

1. RTL-SDR Drivers:

2. RTL-SDR Tools:

3. SatDump for Meteor-M LRPT decoding (required for weather satellites):

4. rtl_433 for ISM band decoding (optional but recommended):

5. POCSAG Decoder (optional):

5. Python 3.10+

Install from Source

Required Python Packages

The following are installed automatically:

• pyrtlsdr - RTL-SDR hardware interface

• numpy - Signal processing

• scipy - Filtering and demodulation

• mcp - Model Context Protocol server

• Pillow - Image processing for NOAA satellite images

• pyModeS - ADS-B decoding (optional)

🎯 Quick Start

1. Configure Claude Desktop

Edit ~/Library/Application Support/Claude/claude_desktop_config.json (macOS) or equivalent:

Important: Use absolute paths for the Python interpreter.

2. Restart Claude Desktop

Quit and restart Claude Desktop to load the MCP server.

3. Test the Connection

In Claude Desktop:

You should see: "Successfully connected to RTL-SDR"

📡 Supported Hardware

📊 Protocol Support

Protocol Details

ADS-B (1090 MHz):

• Uses rtl_adsb subprocess for demodulation

• pyModeS for message decoding

• Tracks aircraft position, speed, altitude, callsign

• FULLY TESTED AND WORKING

POCSAG (152/454/929 MHz):

• Uses multimon-ng for professional decoding

• Supports 512/1200/2400 baud

• Alphanumeric and numeric messages

• Common frequencies: 152.240 MHz, 454 MHz, 929-931 MHz

AIS (161.975/162.025 MHz):

• GMSK demodulation (simplified)

• Decodes ship position, speed, type

• Requires coastal location

Meteor-M LRPT (137 MHz):

• Uses satdump subprocess for OQPSK demodulation

• Digital LRPT transmission with error correction

• Decodes visible and infrared channels

• Active satellites: Meteor-M2-3 (137.9 MHz), Meteor-M2-4 (137.9 MHz primary, 137.1 MHz backup)

• CURRENT WEATHER SATELLITE STANDARD (replaced NOAA APT)

NOAA APT (137 MHz) - DEPRECATED:

• AM demodulation (analog)

• All NOAA APT satellites decommissioned August 2025

• Tool remains for historical/testing purposes

• ⚠️ Use Meteor-M LRPT for current weather satellite imaging

ISM Band (433/315/868/915 MHz):

• Uses rtl_433 subprocess for decoding

• Multi-frequency hopping support

• Decodes 200+ device types automatically

• Weather stations, sensors, doorbells, tire pressure monitors, remote controls

• Common frequencies: 433.92 MHz (EU/Asia), 315 MHz (NA), 868 MHz (EU), 915 MHz (NA)

🛠️ Available MCP Tools (27 Total)

Core SDR Control (5 tools)

• sdr_connect - Connect to RTL-SDR or HackRF

• sdr_disconnect - Disconnect from SDR

• sdr_set_frequency - Set center frequency in Hz

• sdr_set_gain - Set gain (dB or 'auto')

• sdr_get_status - Get hardware status

Aviation (3 tools)

• aviation_track_aircraft - Start ADS-B tracking on 1090 MHz

• aviation_stop_tracking - Stop tracking

• aviation_get_aircraft - Get list of tracked aircraft

Pager Decoding (3 tools)

• pager_start_decoding - Start POCSAG decoder

• pager_stop_decoding - Stop decoding

• pager_get_messages - Get decoded messages

Marine (3 tools)

• marine_track_vessels - Start AIS ship tracking

• marine_stop_tracking - Stop tracking

• marine_get_vessels - Get vessel list

Weather Satellites (2 tools)

• satellite_decode_meteor - Decode Meteor-M2-3/M2-4 LRPT satellite pass (CURRENT)

• satellite_decode_noaa - Decode NOAA APT satellite pass (DEPRECATED - satellites decommissioned)

ISM Band Devices (3 tools)

• ism_start_scanning - Start scanning ISM bands (433/315/868/915 MHz) with multi-frequency hopping

• ism_stop_scanning - Stop ISM band scanning

• ism_get_devices - Get detected devices (weather stations, sensors, etc.)

Analysis (5 tools)

• spectrum_analyze - Analyze RF spectrum (FFT, signal detection)

• spectrum_scan - Scan frequency range

• recording_start/recording_stop - Record raw IQ samples (saved to /tmp/sdr_recordings/)

• audio_record_start/audio_record_stop - Record demodulated audio as WAV (FM/AM)

HackRF Transmit (2 tools)

• hackrf_set_tx_gain - Set transmit gain

• signal_generator - Generate and transmit signals

📖 Usage Examples

Track Aircraft

After 30-60 seconds:

Decode Pagers

Wait a few minutes, then:

Note: Check RadioReference.com for active pager frequencies in your area.

Analyze Spectrum

Scan for Signals

Record Audio from FM Radio

Wait for desired duration (e.g., 30 seconds), then:

Files saved to: /tmp/sdr_recordings/audio_YYYYMMDD_HHMMSS_XXXMHz_FM.wav

Record Raw IQ Samples

Wait for desired duration, then:

Files saved to: /tmp/sdr_recordings/recording_YYYYMMDD_HHMMSS_XXXMHz.iq

Use case: Advanced analysis, replay, or processing with GNU Radio/SDR#

Meteor-M Weather Satellite (when overhead)

Requirements:

• SatDump installed (brew install satdump)

• Satellite pass overhead (use tools like Gpredict, N2YO, or Heavens-Above to predict passes)

• Ideally a V-dipole antenna tuned for 137 MHz

What you get:

• Visible light channel images

• Infrared channel images

• Composite RGB images

• Saved to /tmp/sdr_recordings/meteor_METEOR-M2-4_*/

Tips:

• Meteor-M2-4 transmits on 137.9 MHz (primary) or 137.1 MHz (backup)

• Best results with satellite elevation >30°

• Full pass is typically 10-15 minutes

• Use higher gain (40-49 dB) for weak signals

NOAA Satellite - DEPRECATED

⚠️ Note: All NOAA APT satellites were decommissioned in August 2025. This tool remains for historical purposes only. Use satellite_decode_meteor for current weather satellite imaging.

Scan ISM Band Devices

Wait 1-2 minutes for devices to transmit, then:

Common devices detected:

• Weather stations (temperature, humidity, wind, rain)

• Wireless thermometers

• Tire pressure monitoring systems (TPMS)

• Door/window sensors

• Doorbells and remote controls

• Soil moisture sensors

Tips:

• Weather stations typically transmit every 30-60 seconds

• 433.92 MHz is common in Europe/Asia

• 315 MHz is common in North America

• Try different frequency combinations: [433.92, 315] or [868, 915]

• Increase hop interval for more dwell time per frequency

🔧 Development

Project Structure

Architecture

Device Management:

• RTL-SDR and subprocess decoders use exclusive device access

• Python SDR control and subprocess tools (rtl_adsb, rtl_433) cannot run simultaneously

• Subprocess-based decoders automatically disconnect Python SDR

• Stopping decoder reconnects Python SDR control

Decoders:

• ADS-B: rtl_adsb subprocess + pyModeS

• ISM Band: rtl_433 subprocess with JSON output + multi-frequency hopping

• POCSAG: rtl_fm + multimon-ng pipeline

• AIS: Built-in GMSK demodulator (simplified)

• NOAA: Built-in AM demodulator + sync detection