ESTIMATION OF TIME REVERSAL TARGET DOA OVER UNDERWATER ACOUSTIC MULTIPATH TIME-VARYING CHANNELS

When the channel characteristics between uniform motion target and uniformed linear array (ULA) are changed, how to get the target DOA estimation using time reversal (TR) is discussed in this paper. First, based on the research of underwater acoustic multipath time-varying channel, the model of receiving array signal is analyzed, and then characteristics of time-delay spread are improved by TR of receiving array signal; Based on frequency reversal (FR), a TR method of each path recovered source signal is proposed; Finally, target DOA model is built by TR combined with FR (TR-FR). Simulation results show that the signal frequency offsets caused by multipath channel is involved with the number of array and multipath, and the performance of target DOA estimation based on TR-FR over underwater acoustic multipath time-varying channel is better than conventional TR methods.