水声OFDM通信系统中一种新的信道估计方法

A new channel estimation method for underwater acoustic OFDM communication systems

研究了水声正交频分复用(OFDM)通信系统中的信道估计问题。通过分析水声信道的稀疏性结构特点及其统计特性,获得了基于最小误判的最优筛选门限。利用该门限能够最大限度地判别非零值信道抽头位置。在此基础上,采用结构LS方法进一步对非零值抽头进行精确估计,从而获得水声信道的精确估计值。通过计算机仿真,在两种不同稀疏信道情况下,验证了文中算法的有效性。该算法简单、快速,便于实际应用。

The method of sparse channel estimation was investigated for underwater acoustic OFDM communi- cation systems. After analyzing the sparse structure of underwater acoustic channels and their statistical properties, an optimal threshold of sparse channel estimation was obtained by minimizing the probability of error of detecting the nonzero channel taps and zero-value taps. Then the nonzero channel taps were acurately estimated by using the structured least square method. Through the computer simulations, the effectiveness of the proposed estimation method was validated under two different channel conditions. The proposed method is comparatively simple and fast, and it is more suitable for practical application compared with other estimation methods.