Mitigating Motion Artifacts in Non-contact Respiratory Rate Measurement Utilizing mm-Wave FMCW Radar

This paper presents an innovative approach to respiration-rate or breath-rate (BR) measurement using Texas Instruments’ 77 GHz AWR1843BOOST FMCW radar, addressing challenges posed by motion artifacts and external interference. The system employs the Fast Fourier Transform (FFT) for range estimation, followed by phase extraction and unwrapping for accurate respiratory signal capture. Beyond traditional bandpass filtering (BF), advanced signal processing methods, viz. Wavelet Denoising (WD), Savitzky-Golay Filtering (SGF), and Kalman Filtering (KF) are comparatively analyzed. SGF reduces root mean square error (RMSE) in BR by 40%, excelling at noise reduction at short ranges. WD lowers RMSE by 30% at longer ranges, while KF offers the best computational efficiency. These techniques improve non-contact BR measurement in the presence of motion artifacts.