You can use mmWave sensors to monitor presence rather than simply detecting motion.

Consumer devices like cell phones are using more and more sensors to save power and enhance our interaction with them. Some of the latest devices have more than 10 sensors. It is a natural question ...

I recently had to build an infrared close proximity sensor that could tell if something was dropped in a parcel delivery drop box. After some searching, I ended up using a microcontroller and a piece ...