Vital signs monitoring for different chest orientations using an FMCW radar
In this work the ability of a frequency modulated continuous wave (FMCW) radar to measure the respiratory rate and the heartbeat of a subject in challenging scenarios is tested. The radar, operating in the 5.8 GHz industrial, scientific and medical (ISM) band, has been suitably designed for the proposed application. Four different orientations of the target with regards to the radar antenna have been considered: the measured subject has been positioned with the breast, the left side, the right side and back facing the antenna. In all the scenarii the vital signs have been successfully extracted from the radar signal and compared with a photoplethysmograph and a respiratory belt. The radar was capable of measuring both the respiratory rate and the heartbeat with high accuracy.