Heart rate measurement method based on wavelet transform noise reduction for low power millimeter wave radar platform

Abstract

In recent years, non-contact vital sign estimation using millimeter wave radar technology has gotten much attention. Most studies are based on radar platforms that were not built for home scenarios and had high transmitting power and colossal volume. This work employs a low-power millimeter wave radar system produced using Antenna in Package technology (AiP) with a transmit power of less than 6 dBm, significantly lower than that commonly utilized in related research. However, in application scenarios, the echo intensity cannot be maintained at an optimal level with these low-power devices, making accurate and reliable monitoring difficult to obtain. To further reduce the noise component and improve the signal-to-noise ratio, a heartbeat monitoring algorithm based on wavelet transform noise reduction is suggested in this study. The low-frequency terms of the wavelet transform of the chest wall micro-motion signal are interpreted as body random swinging and breathing, and the remaining terms are interpreted as the heartbeat signal. In a 20-minute monitoring experiment, 96.96% accuracy is reached by the method proposed in this study in the context of home scenario monitoring.