Circuit, Antenna, and Algorithm Co-Design of CMOS-Integrated Coherent FMCW Radar Sensor for Edge Vital Signs Monitoring

This paper presents a chip-based Ku-band coherent frequency modulated continuous wave (FMCW) radar sensing platform operating at the 15-GHz center frequency for realizing telemedicine and vital signs monitoring at the edge with the specifically designed antenna and interferometric phase analysis algorithm. A configurable chirp synthesizer is implemented with a direct digital synthesizer (DDS) for ensuring the chirp signal generation with high phase accuracy and excellent power efficiency. Empowered by the specifically designed antenna with high gain and phase-domain processing, accurate vital signs monitoring can be achieved. Fabricated in a 65-nm CMOS process, the prototype radar chip operates with smaller than 250-mW at a 1.2-V power supply, which ensured the low-power operation for long-term edge health status monitoring. Experiments on discerning vital signs were conducted based on the FMCW radar chip platform with a specific antenna and DE-10 edge processing unit. Further, the radar platform can be integrated into a more compact level with AI-based signal processing implemented on-chip to attain more efficient performance on multimodal health status monitoring at the edge with enhanced energy efficiency.