A pilot-free channel estimation algorithm for orthogonal multicarrier spread spectrum communication via sparse underwater acoustic channel

A pilot-free channel estimation algorithm is proposed.This algorithm utilizes the sparseness of underwater acoustic channel to effectively recognize the spread spectrum signal.Then the channel response is estimated using decision feedback scheme according to the result of recognition,thereby realizing the robust reconstruction for underwater acoustic channel.The results obtained by Monte Carlo simulation and lake-trial are provided,demonstrating that the proposed algorithm can realize a reliable equalization and effectively improves the efficiency of underwater acoustic communication without losing the robustness.