DOI: 10.1109/TMTT.2023.3324444   IEEEXplore: https://ieeexplore.ieee.org/document/10297954

CW quadrature Doppler radar with a 100 Hz sampling rate

2.4 GHz

1) The respiration harmonics content of the heart signal is significantly reduced with arctangent demodulation of the I and Q channel signals. 2) The heart signal is extracted from the AD signal with signal processing techniques incorporating multiresolution analysis, maximal overlap discrete wavelet transform (MODWT) and a template matching filter (TMF).

Up to 87.14% reduction in respiration harmonic content of the I-channel signal and 83.03% reduction for Q-channel by arctangent demodulation; 12.43 ms mean absolute error (MAE) of the beat-to-beat interval (BBI).