This ESP32 Antenna Array Can See WiFi

Author here. I agree with you, "full spectrum" is a generous marketing phrase for what might more accurately be called _extended_ spectrum. People way smarter than me have been able to achieve DIY spatial imaging with x-rays via compressed sensing [1] and with microwaves via phased arrays [2]. Optical wavelengths seem to be at a sweet spot of good angular resolution, varied natural sources, and harmless to humans. [1] link [2] ▶ this video

I was really impressed that a ESP32 Antenna Array Can essentially make a WiFi camera - it uses both time and phase differences to localize based on MAC addresses (which are sent plaintext) ▶ this video

As shared elsewhere in this thread: ▶ this video TL;DW: the ESP’s WiFi driver provides per incoming packet the carrier’s phase and amplitude. All ESPs are calibrated relatively to each other.

This project uses an array of ESP32s and some clever calibration techniques to do pretty accurate localisation of WiFi signals. There's an excellent companion video here: ▶ this video