|Doppler Radar Tracking Babies - Science Insider
Reported March 2009
HOW DOES IT WORK? The monitor is about the size of a small book. It attaches to the crib, while parents keep a remote station with lights to indicate the status of the baby's vital signs, battery life, and wireless connection status. The monitor sends radar waves toward the baby to measure the constant rising and falling of the breathing baby's chest. If the monitor measures that the breathing falls below a certain threshold or stops, the remote station flashes and sounds an alarm. Adding a higher frequency signal to the monitor could allow it to measure heartbeat.
WHAT IS DOPPLER RADAR: Doppler radar uses a well-known effect of light and sound called the Doppler shift. Just as the pitch of a train whistle will sound higher as it approaches a platform and then become lower in pitch as it moves away, light emitted by a moving object is perceived to increase in frequency (a blue shift) if it is moving toward the observer; if the object is moving away from us, it will be shifted toward the red end of the spectrum. Doppler radar sends out radio waves that bounce off objects in the air, such as raindrops or snow crystals, and then measures how much the frequency changes in returning radio waves to better determine wind direction and speed
The Institute of Electrical and Electronics Engineers, Inc.-USA, contributed to the information contained in the TV portion of this report.
If you would like more information, please contact:
Jacob Neil Boger Foundation
Institute of Electrical and Electronics Engineers, Inc. IEEE-USA
Washington, DC 20036-5104