Respiration and heart rates measurement using 77GHz FMCW radar with blind source separation algorithm

This paper presents a blind source separation based signal processing method of measuring respiration and heartbeat rates using frequency modulated continues wave (FMCW) radar with working frequency range 77GHz-81GHz. To improve signal quality, complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN) method is used in preprocessing stage to first decompose the phase signal into several intrinsic mode functions (IMFs) and then the phase signal is reconstructed by adding the selected IMFs. The accurate measurement results can be obtained by the proposed method both in separating respiratory and heartbeat signals of one person (the average deviations are 1.1 beat per minute and 6.8 beat per minute respectively), and in separating respiratory signals of two persons.