Your WiFi Router Can Now Track Your Body Through Walls

WiFi-DensePose is an open-source system that turns a commodity WiFi router into a through-wall body tracking sensor. By analyzing Channel State Information (CSI) — per-subcarrier amplitude and phase data — it reconstructs your full body pose map in real time as signals bounce off your body.

The tech traces back to CMU's 2023 paper "DensePose From WiFi" (arXiv:2301.00250), but a recent Rust rewrite pushed performance to 54,000 frames/sec with sub-50ms latency — roughly 800x faster than the original Python impl. It runs on a $9 ESP32 chip, no cloud, no internet required. Vital sign monitoring (breathing rate, heartbeat) comes included.

The GitHub repo went viral, pulling tens of thousands of stars in a single day. Privacy researchers are already raising flags — any apartment building with multiple WiFi networks is now, theoretically, a sensor array.

Why it matters: passive, camera-free pose tracking at this cost and accuracy redraws the line between smart home and surveillance — and it's already in everyone's hands.