Slow-Time Waveform Randomization Performance under Incoherent FMCW Radar Interference

With the rising utilization of radars on vehicles, interference among vehicular radars in dense traffic scenarios is an emerging problem awaiting innovative solutions. In this work, we consider incoherent FMCW radar interference cases where different FMCW radars use different chirp slopes. Our simulation shows that under the simplest spectrum access scheme - random frequency division multiplexing (RFDM), the false alarm caused by incoherent interference is a serious issue. We study the interference mitigation performance of three slow-time waveform randomization schemes: frequency hopping (FH), joint RFDM and phase coding (PC), and joint FH and PC. Our comparative study shows that not all slow-time waveform randomization schemes perform well under incoherent interference. FH even achieves worse false alarm performance than RFDM. Joint RFDM and PC achieve the best trade-off between the probability of false alarm and the probability of target detection.