The reverberation suppression in wideband diver detection sonar

The reverberation suppression is the foundation of target detection in diver detection sonar. The reverberation caused by the sea bottom is generally strong. Conventional methods with only amplitude cannot remove these reverberations completely because of the random temporal fluctuation of the signal amplitude, which causes false alarms especially in the small target detection. Spatiotemporal stability derived from the variance of phase difference which is independent from the amplitude has been adopt to the reverberation suppression for narrow band signals in diver detection sonar systems, which are more complicated in wide band sonar. Wideband signals have the predominance of narrow band signals, because of the better resolution in range and azimuth. To access the high resolution and low false alarm simultaneously, the reverberation suppression combining amplitude with phase difference in wide band diver detection sonar needs to be achieved. So this paper proposed an improved method to suppression the reverberation for the wideband sonar system. The spatiotemporal stability estimation is proposed to be achieved based on the wavelet cross spectrum after wideband split-beam forming. The estimation algorithm in the wavelet domain is discussed. And the experiment results are given at last.