FMCW Radar-based Vital Signal Monitoring Technique Using Adaptive Range-bin Selection

This paper aims to propose a signal processing technique for non-contact sensing of vital signs such as respiration and heart-rate using FMCW radar. Existing studies have limitation of only detecting vital signs for a fixed target, but in this study, we propose vital signs sensing technique for a moving target. We propose a novel algorithm that tracks the optimal distance information through the correlation between the distance information from the moving target and the magnitude and energy density of the phase information that responds to vital signs. The novel algorithm is based on signals from FMCW radar sensors that can extract range information from moving objects. The proposed algorithm is verified through a compact module through a 60GHz commercial FMCW radar sensor and a radar signal processor. The experimental results show that the proposed algorithm has a 4.5 bpm error in heart rate, while conventional techniques have an error of 11.4 bpm.