Performance analysis of DOA estimation for MIMO sonar based on experiments

In this paper, a Multiple Input Multiple Output (MIMO) monostatic sonar scheme that can deal with multiple targets is presented, where orthogonal waveforms are transmitted simultaneously. Meanwhile the Capon estimator for this sonar system is derived in detail. And the performance of the MIMO sonar is analyzed via experiments in an anechoic water tank, as compared with its phased-array counterpart. The used sonar array is a uniform linear array with 10 closely spaced elements. Experimental results show that, by orthogonal transmit, this sonar system could achieve 12~15 dB additional array gains over its phased-array counterpart, which means the maximum detection range could be doubled; also, the angle resolution capability could be significantly improved at lower SNR.