Single Conversion Stepped-Frequency Continuous-Wave Radar Using Self-Injection-Locking Technology

Abstract

This paper presents a single conversion stepped-frequency continuous-wave (SCSFCW) radar that uses self-injection-locking technology to achieve high sensitivity, Doppler resolution and range resolution. Moreover, the radar is capable of extracting tiny Doppler shifts from different range bins, so it has great potential to monitor vital signs of multiple people simultaneously. In the experiment, a 7.95-8.95 GHz SCSFCW prototype radar was constructed by an RF up-down converter pumped with a 5.5-6.5 GHz stepped chirp signal and a 2.45 GHz IF self-injection-locked (SIL) radar to successfully localize and recover two individual Doppler signals, each caused by either a small periodical movement of a metal plate or a physiological movement of a human body.