Fast Estimation of Underwater Acoustic Multipath Channel Based on LFM Signal

For underwater acoustic communication systems, there are serious multipath effects in underwater acoustic channels. Intersymbol interference caused by multipath effects is a key factor affecting underwater acoustic communication systems. In order to estimate the multipath time-delay characteristics of shallow ocean acoustic channels, a fast underwater acoustic multipath channel estimation algorithm based on linear frequency modulation (LFM) signal is proposed in this paper. Design the LFM frame header at the transmitting end, and use the correlation characteristics of the LFM signal at the receiving end to correlate the received LFM signal. By setting the corresponding decision parameters, the multipath delays of the underwater acoustic channel and the corresponding amplitudes can be quickly estimated. In order to verify the effectiveness and fastness of the algorithm, the experimental results of multipath delay estimation using ideal channel simulation and marine experimental data are given.