evilSDR

Overview

A lightweight, performant SDR receiver focused on stability and audio quality. This is a ground-up rewrite to address previous performance issues (audio skipping).

Features

• High Performance: Optimized DSP pipeline using FIR filters and polyphase decimation.
• Stable Streaming: Minimal latency and no audio skipping (ring buffer implemented).
• Audio & IQ Recording:
  • Record demodulated audio to WAV.
  • Capture raw IQ data for offline analysis.
• Scanning:
  • Frequency Scanning: Sweep a range of frequencies (Start/End/Step) to find active signals.
  • Memory Scanning: Cycle through saved bookmarks.
• Demodulation:
  • WBFM: Wideband FM (Broadcast Radio).
  • NBFM: Narrowband FM (Walkie Talkies, Emergency Services).
  • AM: Amplitude Modulation (Air Traffic).
• Configuration: User-space configuration via src/backend/config.json.

Structure

• src/backend: Python-based SDR interface and DSP pipeline.
• src/frontend: Web-based visualization (Waterfall/Spectrum).
• src/shared: Common utilities.
• tests: Unit and integration tests.
• docs: Project documentation.
• scripts: Utility scripts for setup/running.
• recordings: Directory where Audio/IQ files are saved.

Roadmap

• Phase 1 (Complete): Stable RTL-TCP connection, minimal DSP, basic waterfall/spectrum visualization.
• Phase 2 (Complete): Audio demodulation (WBFM/NBFM), Audio/IQ Recording, and upgraded FIR-based DSP.
• Phase 3 (In Progress): Advanced decoders (ADSB, TV/ATV), Plugin Architecture.

Getting Started

Prerequisites

• Python 3.9+
• RTL-SDR dongle (and rtl_tcp running or accessible)

Installation

1. Clone the repository:

   git clone https://github.com/google-deepmind/evilSDR.git
   cd evilSDR

2. Create a virtual environment (recommended):

   python -m venv venv
   source venv/bin/activate  # On Windows: venv\Scripts\activate

3. Install dependencies:

   pip install -r requirements.txt

Configuration

1. Copy the example configuration:

   cp src/backend/config.json.example src/backend/config.json

2. Edit src/backend/config.json to match your environment (e.g., rtl_host, rtl_port).

Running

1. Start the backend server:

   python src/backend/server.py

2. Open the frontend in your browser:

   http://localhost:5555