RCWL-0516 Microwave Radar Sensor Experiences?

Hardware
61

If I could correct you: Microwaves do not need a metal surface to be reflected. Any EM wave is partially reflected when travelling into a medium that has a different refractive index - eg a human body. Although I agree it is FULLY reflected from a metal surface.

Secondly, if I could comment on my use of these RCWL devices, I found them very susceptible to 2.5GHz emissions - ie those emitted by the CPU in the wifi band. I got very fewer spurious detections if I separately mounted the RCWL about a meter away from the ESP cpu. This could be a good reason why the newer mm microwave sensors which operate at ~60GHz, will be less susceptible to wifi signals.

62

Just been exploring this sensor to trigger my camera to record on motion. But it seems that it cannot be relied upon due ot heat build up. I am using it with the Raspberry Pi Zero2 and there is no way I can create enough distance in the camera case I am using, I hear what you say about influencing the sensitivity of the sensor using a resistor but you say not all sensors are the same because they are cheaply mass produced. Very useful research by you which saves me a lot of time of development. I wish your findings were more common knowledge. Thanks