Aitrip 8pcs Microwave Radar Sensor RCWL-0516 Switch Module Human Board Induction Board Detector 5-7M Detection Distance 4-28V Compatible with Arduino Raspberry PI,Human Rat Cat Detector

Easy to attach and configure as a motion sensor for raspberry pi. Very sensitive and instantly switches ON or OFF.

Super easy to use, but after trying to get an analog signal from the onboard chip it became apparent that you cannot use this to do radar imaging and you cannot detect distance/speed like true doppler.Still works great as a motion detection module and you can customize the deadtime with resistors or by adding a potentiometer to tune it on the fly.

The price is right, worked OK with an ESP32 CPU and ESPHome firmware, to act as reliable occupancy/presence sensor. Using these outside (at a weather-protected doorway) to sense people near my doorway; and indoors to sense people sitting with only slight motion in front of the TV (PIR sensors were giving me too many false positives outside, and failing for indoor seated people). Still needs some "tuning" of the ESPHome software (or maybe I'll need to add a Lambda filter) to "de-bounce" the occupancy triggers.

I only had one of the 8 work. Not sure what the issue was, but I soldered a couple and I had coworkers solder some as well in case I was just inept. Nope, I got one working and no one could get any others to work.

These are much smaller than infrared detectors and can be hidden in plastic containers and/or behind walls.They're just as easy to connect to an Arduino-type device and just as easy to program as a PIR.

For a fully functioning radar module, youre going to have to spend many hours trying to tweak this module. If you dont have any resistors, might want to consider purchasing...otherwise the sensitivity is all over. When you also consider its non-directional, (360degrees) be prepared to get out the tin foil to limit detection directions.A better design would have included the resistors and capacitors need to change sensitivity, and then change with jumpers or solder pads.Wish I could say this was the answer.. But it's not- I have more accurate PIR sensors.

Every single board had resistors and caps destroyed on it. And some the IC on the back was broken off. Only got one working board. I recommend not using this brand

I built an Arduino-based temperature/humidity/pressure monitoring system for my radio shack. I used an OLED display, and they will eventually burn up if they are left "lit" all the time. So I added this device to sense my presence, wake up the Nano, and display the information for a limited amount of time. It saves energy, greatly increases the display's life, and works like a charm.Great little device.