Active Breathing Suppression for Improved Sleep Monitoring Heartbeat Detection Using UWB Radar

In this paper, we present a new observation when processing backscattered radar signals from a sleeping subject on a normal mattress. A breathing motion magnification effect is observed because of mattress surface displacement due to human respiratory activity. This undesirable motion artifact causes existing methods for accurate heart-rate estimation to fail. We therefore propose a novel active motion cancellation technique to deal with this problem by intelligently selecting slow-time series from multiple ranges and examining the corresponding phase difference. Finally, we validate our approach through experimental study.