Signal Decomposition Based Mutual Interference Suppression in FMCW Radars

Abstract

With the increasing use of frequency modulated continuous wave (FMCW) radars in autonomous vehicles, mutual interference among FMCW radars poses a serious challenge. In this work, we present a novel approach to effectively and elegantly suppress mutual interference in FMCW radars. We first decompose the received signal into modes using variational mode decomposition (VMD) and perform time-frequency analysis using Fourier synchrosqueezed transform (FSST). The interference-suppressed signal is then reconstructed by applying a proposed energy-entropy-based thresholding operation on the time-frequency spectra of the VMD modes. The effectiveness of the proposed method is measured in terms of signal-to-interference plus noise ratio (SINR), correlation coefficient, and probability of detection in the presence of FMCW interference. Furthermore, the interference suppression ability of the proposed VAFER scheme is evaluated for stationary and moving target scenarios by performing a range Doppler analysis in the presence of interference. Compared to the existing literature, the proposed method demonstrates significant improvement in the output SINR by at least 15.46 dB for simulated data and 9.87 dB for experimental data.