Multi-Target Vital-Signs Monitoring Using a Dual-Beam Hybrid Doppler Radar

This paper presents the preliminary results of a novel approach for multi-target vital-signs monitoring using an electromagnetic-based Doppler radar. The fundamentals of the proposed approach are based on multi-beam antennas, phased arrays systems, and beam-forming networks. For the purpose of demonstration, we have designed and implemented a prototype dual-beam phased-array continuous-wave Doppler radar operating at 2.4 GHz. Measurement results confirmed the feasibility of the proposed method. Experimental measurements showed that for the first time, the breathing rates of two individuals can be monitored at the same time and using the same frequency. The proposed dual-beam system prevents the phase collision of the signatures of the targets and hence provides multi-person detection capability for the system.