An injection-locked detector for concurrent spectrum and vital sign sensing

This paper proposes a concurrent spectrum and vital sign sensor using an injection-locked detector. To achieve this goal, two different sensing mechanisms are involved. One is to employ the injection locking and pulling effects in an oscillator to fast detect the frequency and power of a wireless communication signal. The other is to use a self-injection-locked oscillator to detect Doppler shift for measuring the breathing and heartbeat rate of a target. A prototype system operating in S-band has been implemented to validate the proposed sensor architecture.