Heart Rate Variability Assessment Using Single Channel CW Doppler Radar
Heart Rate Variability (HRV) represents the variation in the interbeat interval of a heart signal and is also a reflection of the adaptability of the cardiovascular system to unexpected physiological and psychological changes. Radar-based non-contact HRV measurement can play a significant role in monitoring the health of an individual in a non-contact and unobtrusive manner. Prior research on HRV measurement mostly focused on using quadrature channel Continuous Wave (CW) radar, Frequency Modulated CW (FMCW) radar, and IR Ultra Wide Band (UWB) radar. A single-channel CW radar has a simpler architecture and fewer signal processing steps than the quadrature radar. This paper investigates the feasibility of utilizing a single-channel CW radar in ultra-short-term HRV analysis. Preliminary results showed a strong correlation of the HRV time and frequency domain metrics from the radar signal with that of an ECG signal and thus proved to be reliable in the accurate assessment of HRV.
