Comparative Study of Radar Architectures for Human Vital Signs Measurement

Radars can be used as a non-invasive solution to monitor the vital signs of patients. The heart and respiratory rates are generally extracted by analyzing the phase variations of the radar signal, thus motivating the use of millimeter-waves. This, however, comes at the cost of a higher attenuation with the distance of travel, which in turn lowers the signal to noise ratio. While the state-of-the-art considers various architectures of millimeter-wave (mmW) radar for vital signs extraction, they are seldom compared in terms of hardware complexity and power consumption even though these aspects are of utmost importance for autonomous applications. This paper presents a comparative analysis of the state-of-the-art short-range radar solutions and takes into account their respective hardware complexity needed to improve the signal to noise ratio. It aims to select the most relevant low-power architecture for an autonomous application. Analytical models for power estimations are presented and compared with simulation results. Finally, in light of these performances the architectures complexities over their respective hardware limitations are discussed.