Wi-Fi CSI Looked Like a Sensor Hidden Inside the Radio
Channel State Information exposes how multipath changes, which turns ordinary Wi-Fi links into crude environmental sensors.
Channel State Information exposes how multipath changes, which turns ordinary Wi-Fi links into crude environmental sensors.
Someone enters a room and the graph changes. It is a compelling demo, but it is not yet evidence of reliable presence detection. Signals can change for reasons other than a person entering the space.
Setting a calibration value does not guarantee that every future measurement will remain correct. The environment, reference, and operating range in which that value was created are part of its meaning. Calibration is a rule for interpreting a measurement.
Keeping the ESP32 focused on reliable CSI capture and moving heavier analysis elsewhere made the sensing pipeline easier to debug.