Hough Transform and Time-Frequency Ridge-Based Interference Mitigation in Automotive FMCW Radars

As frequency modulated continuous wave (FMCW) radars are becoming a key component of autonomous driving technology, mutual interference among automotive FMCW radars is a significant challenge. In this work, we propose a novel signal processing solution to effectively mitigate mutual interference among FMCW radars. The proposed framework distinguishes the target echoes and interference using their characteristics in the time-frequency spectrum, both of which appear as lines but with different slope characteristics. An interference map is generated from the interference contaminated time-frequency spectrum by employing the Hough transform along with slope filtering. The interference map is then used as a mask for interference mitigation. The interference-mitigated signal is reconstructed by applying time-frequency ridge-based mapping to subjugate the power loss associated with the target signals. We carry out extensive simulations to demonstrate the interference mitigation capabilities of the proposed Hough trans-form and time-frequency ridge (HTFR)-based scheme in terms of the signal-to-interference plus noise ratio (SINR), correlation coefficient, and computational efficiency.