We present a variational message passing (VMP) approach to detect the presence of a person based on their respiratory chest motion using multistatic ultra-wideband (UWB) radar. In the process, the respiratory motion is estimated for contact-free vital sign monitoring. The received signal is modeled by a backscatter channel and the respiratory motion and propagation channels are estimated using VMP. We use the evidence lower bound (ELBO) to approximate the model evidence for the detection. Numerical analyses and measurements demonstrate that the proposed method leads to a significant improvement in the detection performance compared to a fast Fourier transform (FFT)-based detector or an estimator-correlator, since the multipath components (MPCs) are better incorporated into the detection procedure. Specifically, the proposed method has a detection probability of 0.95 at -20 dB signal-to-noise ratio (SNR), while the estimator-correlator and FFT-based detector have 0.32 and 0.05, respectively.
@article{arxiv.2210.07619,
title = {Variational Message Passing-Based Respiratory Motion Estimation and Detection Using Radar Signals},
author = {Jakob Möderl and Erik Leitinger and Franz Pernkopf and Klaus Witrisal},
journal= {arXiv preprint arXiv:2210.07619},
year = {2022}
}
Comments
29.10.22: Updated with extension to multistatic radar systems. Submitted to ICASSP 2023, 4 pages + references, 4 figures, UWB radar rar occupancy detection, variational message passing