High Resolution CMOS IR-UWB Radar for Non-Contact Human Vital Signs Detection

This paper presents an impulse radio ultra-wideband radar transceiver chip for monitoring human vital signs, featuring a spectrum adjustable transmitter and equivalent time sampling based receiver. The radar receiver samples the echo signal at 20.48 GS/s, which corresponds to a 7.4 mm range resolution using high-speed track and hold sampler. The received pulses are added up to increase the SNR of the receiver. With the proposed pseudo 16-bit DAC, an embedded DC-offset cancellation circuit can improve the dynamic range of the receiver according to the gain of integrator. Respiration and heartbeat of humans were detected by the proposed UWB radar transceiver, while consuming 55.2 mW from 1.2 V power supply. The radar transceiver chip was implemented in a 130 nm CMOS technology occupying chip area of 5.04 mm².