Integrating Millimeter-Wave FMCW Radar for Investigating Multi-Height Vital Sign Monitoring

The millimetre-wave (mmWave) based frequency-modulated continuous wave (FMCW) radar is a pioneering technique for non-invasive vital sign monitoring, specifically designed for integration within 5G/Beyond 5G (B5G) network environments. In this study, we focus on evaluating the accuracy of the FMCW radar in measuring heart rate (HR) and respiratory rate (RR) at various heights relative to the subject's chest. To harness the low-latency benefits of advanced wireless technologies, the mmWave radar operates in tandem with the real-time data-capture adapter (DCA1000) evaluation module, facilitating the high-speed transmission of vital sign data. We employed two signal-processing methodologies, fast fourier transform (FFT) and peak count, to analyze and validate the radar's precision and consistency against reference sensors. Our results underscore the effectiveness of the peak count method, which demonstrates superior accuracy, with mean absolute error (MAE) values of 5.33 breaths/min for RR and 4.03 beats/min for HR, along with root mean square error (RMSE) values of 5.30 breaths/min for RR and 4.30 beats/min for HR, consistent across all tested heights. The proposed system significantly enhances the reliability and responsiveness of next-generation healthcare systems, offering a robust solution for patient monitoring in various interactive and intelligent real-time settings.