CS-ECE Seminar: Non-Contact Vital Sign Detection and Monitoring
The vital sign detection based on microwave Doppler radar has the capability of measuring vital sign signals, such as heartbeat and respiration, without directly attaching electrodes to the skin, and can measure the vital sign at a distance or even through an obstacle. However, for this non-contact vital sign detection approach, phase noise of the received signal can have serious adverse effects on the detection capability and accuracy since the chest displacement caused by breathing and heart beating, especially heart beating, is small and the vital sign is contained in the phase of microwave signals. We have developed a dual-carrier vital sign detection and monitoring technology that is capable of suppressing the residual phase noise and transmission path noise. The system can automatically adapt to a new environment and adjust the transmitted signals to suppress the noise. The experimental results demonstrate that the heartbeat detection distance of our vital sign detection system is more than doubled comparing with a system without the proposed noise suppression scheme. In addition, we have investigated using the non-contact system for measuring cardiac waveforms and for extracting relevant parameters that may reflect health conditions of the human heart.