A Doppler radar vital sign detection system using concurrent dual-band hybrid down conversion architecture

Abstract

In this paper, a concurrent dual-band hybrid down conversion architecture based on continuous-wave (CW) Doppler radar is demonstrated. The proposed system operates at 2.05-/1.64-GHz simultaneously. The dual-band can solve the null detection point problem generated at quarter-wavelength distance between the target and antenna. The detection results from different channels can be mutually verified to improve the system accuracy. The vital sign can be detected by the radar through the wooden board at higher transmit power. For satisfying the requirements of dual-band RF transmitters, and a two-stage dual-band power amplifier is designed. Experimental results have demonstrated the feasibility of the system.