Vital Sign Detection and Clutter Discrimination Method Based on MIMO FMCW radar

Multi-input multi-output (MIMO) frequency-modulated continuous-wave (FMCW) radar can sense minute body motions, enabling non-contact vital-sign monitoring for applications such as sleep tracking, elderly care, and healthcare. While conventional radar imaging can localize multiple targets, it is limited in distinguishing human subjects from surrounding clutter. In this work, a vital-sign detection and clutter discrimination method using a 77-GHz MIMO FMCW radar is proposed. Range–Doppler maps are constructed by applying a two-dimensional fast Fourier transform (2D FFT) along the fast-time (range) and slow-time (Doppler) dimensions, revealing low-frequency micro-Doppler signatures induced by respiration and heartbeat. Simulations verify that the proposed approach effectively separates human targets from static clutter, and experimental validation using a real radar prototype confirms consistent performance in practical environments. The results demonstrate reliable extraction of vital-sign components and robust human–clutter discrimination, highlighting the feasibility of the method for non-contact bio-sensing applications.