ESPectre is an open-source motion detection system that transforms ordinary Wi-Fi signals into an ambient sensor capable of detecting movement without using cameras, microphones, or additional radio hardware, making it a privacy-preserving and cost-effective alternative for presence sensing and smart home automation. At its core, it analyzes Wi-Fi Channel State Information (CSI) — detailed measurements of how Wi-Fi waves change as they propagate — to mathematically detect disturbances caused by human movement between a Wi-Fi router and an ESP32 microcontroller, eliminating the need for machine learning or training data to operate effectively. Designed to integrate natively with Home Assistant through ESPHome, ESPectre exposes motion and movement intensity sensors directly to home automation dashboards, allowing users to trigger automations like lighting, heating, or security alerts when motion is detected.
Features
- Movement detection using Wi-Fi CSI rather than cameras or PIR sensors
- Native integration with Home Assistant via ESPHome (YAML configuration)
- Uses inexpensive ESP32 hardware (e.g., S3, C6, C3) for affordable deployment
- Automatic subcarrier calibration and adaptive threshold tuning
- Dual support for mathematical algorithms (MVS and PCA) for motion analysis
- Research-oriented Micro-ESPectre component for advanced CSI experimentation