A research project called DoppleSleep can help a person monitor their sleep, according to the MIT Technology Review.
Radar, often thought of as a tool for tracking missiles and speeding cars, may also be handy as a noninvasive way to monitor sleep.
Researchers at Cornell University, the University of Washington, and Michigan State University recently conducted a study in which they used an off-the-shelf radar device to track body movements and heart and breathing rates, sending the data via Bluetooth to a smartphone app to figure out when and how well people are sleeping.