A Study on Adaptively Adjusting Phases Accumulative Number for Remote Heart-Rate Sensing with mm-wave Multi-Chirp FMCW Radar

We proposed a phase accumulation to improve the SNR and accuracy on remote heartrate measurement based on multiple chirps mm-wave FMCW radar. However, specification of radar module has continued to be upgraded and it has become clear that increasing number of the accumulative phases may actually worsen the heartrate estimation accuracy, depending on subject and time of experiment. Therefore, this article proposes adaptive adjusting accumulative number of phases, for remote heartrate measurement based on mm-wave multiple chirps FMCW radar. The method adaptively adjusts accumulative number of phases of the received multiple chirps in each observation window according to a SNR criterion. Experimental result shows effect of the proposed method compared with single chirp and 32-phase accumulated cases, for eight subjects.