A Centimeter Resolution, 10 m Range CMOS Impulse Radio Radar for Human Motion Monitoring

A single-chip impulse radio radar transceiver that enables high-resolution reception with enhanced signal to noise ratio (SNR) is proposed. The radar transceiver, consisting of a spectrum adjustable transmitter and a 100-ps resolution 4-channel sampling receiver, successfully demonstrates in/outdoor human walk tracing, stride-rate, and respiration measurements. The 4-channel sampling receiver, which is robust against pulse distortion, utilizes track and hold samplers and integrators while sharing a single low noise amplifier. By adopting embedded control logic, the sampling receiver achieves control flexibility as well as improved performance. A repetitive reception mode can proportionally increase the SNR of the receive pulse at the cost of a longer pulse acquisition time. DC offset and low-frequency coherent noise problems caused by on-board control clock signals are resolved with the radar architecture. The single chip radar transceiver is fabricated in a 130-nm CMOS technology occupying a chip area of 3.27 mm ². The measured results show that echo pulses are recovered with a centimeter range resolution while consuming 80 mA from a supply voltage of 1.2 V.