Time-Frequency DOA Estimation Based on Radon-Wigner Transform

In the studies of DOA estimation based on time-frequency analysis, eliminating cross interference terms is the key to improve DOA estimation performance for the multi-signal sources situation. PWVD is the most commonly used time-frequency analysis tool for suppressing cross interference terms in WVD. However, the cross terms improvement of PWVD is not so ideal and the estimated results are not so reliable. SPWVD can suppress cross terms better, but the time-frequency concentration performance of signal drops largely. This paper employs RWT (Radon-Wigner transform) as a time-frequency transform tool which is very suitable to describe LFM signals. This method can suppress cross terms in the background of multi sources effectively, possesses good time-frequency concentration performance, and consequently it can improve the accuracy of DOA estimation much more greatly. Simulation results demonstrate that the performances of DOA estimation based on RWT are notably improved compared with those ones based on PWVD and SPWVD