DOA Estimation Method Based on EMD and MUSIC for Mutual Interference in FMCW Automotive Radars

Abstract

Mutual interference in automotive radar will reduce the signal-to-noise ratio (SNR) of the received signals. It is difficult to accurately distinguish the signal subspace and the noise subspace for low SNR signals, which will degrade the direction of arrival (DOA) estimation performance of the multiple signal classification (MUSIC) algorithm. To solve this problem, this letter proposes a DOA estimation method for automotive radar based on empirical mode decomposition (EMD) and MUSIC in the case of interference. In our method, the interference signals are suppressed before the DOA estimation. The received signals of the receiving antennas affected by the interference are decomposed into several components by using EMD, and then the interference signals in the interference components are suppressed. Finally, all the received signals are used for the DOA estimation. The results of the simulation and field experiments show that the proposed method can obtain an accurate DOA estimation when the received signals contain the interference signals, and the performance of the proposed method is better than the existing DOA estimation algorithms.