論文摘要
Abstract—This work presents a 60-GHz fully integrated 90-nm CMOS
direct-conversion vital-signs Doppler radar RF sensor with a quasi-circulator and clutter canceller for single-antenna noncontact vital-signs detection. To achieve a high-sensitivity vital-signs radar sensor, a clutter canceller circuit (consists of a VGA and full 360°adjustable continuous phase-shifter) is very important to cancel the Tx leakage and background reflected clutter. The radar chip consists of 60-GHz VCO, divided-by-2 divider, PA, quasi-circulator (QC), clutter canceller (VGA and 360o phase-shifter), LNA, I/Q sub-harmonic mixer (SHM), and couplers. The measurement shows that the transmitting power is 3 dBm. The conversion gain and input P1dB of the sub-harmonic receiver are 10.5 dB and -23 dBm, respectively. In the human subject vital-signs detection measurement at 75 cm with a 60-GHz patch-array antenna of equivalent gain 10 dBi, the detected heartbeat (1-1.3Hz) and respiratory signals (0.35-0.45 Hz) can be clearly observed. The radar chip size is 2 mm × 2 mm with a consuming power of 217 mW. The developed integrated CMOS vital-signs Doppler RF sensor can be integrated in a handheld device (like smartphone) for wireless health-care application.
Keywords— 60-GHz, circulator, clutter canceller, Doppler radar, millimeter-wave,
