Blind deconvolution of low frequency acoustic signals based on mode decomposition using vertical liner array in shallow water

On the base of the idea of blind deconvolution using artificial time reversal, a blind deconvolution method based on normal mode decomposition is proposed in this paper. This method is suitable for the blind deconvolution of the low frequency underwater acoustic signals received by a vertical liner array (VLA) in shallow water. Firstly, the normal modes of acoustic propagation in the shallow water are extracted (estimated) by mode decomposition from the signals received by a vertical liner receiver array (VLA). Then, the blind deconvolution processing to recover or reconstruct the source signal is achieved by mode filtering according to the estimated normal modes. Numerical simulations in typical shallow water environment demonstrate the effectiveness of the proposed method. The simulation results indicate that the normal modes of the low frequency acoustic field in the shallow water can be extracted successfully from the signals received on VLA by mode decomposition, thus the method presented in this paper remedies the shortages of conventional blind deconvolution method using artificial time reversal processing which requires exact normal mode information. And under the condition of certain signal bandwidth, the performance of the blind deconvolution using mode filters presented in this paper is better than that using artificial time reversal.