中文摘要：

针对最小均方误差准则下（Minimum Mean SquareError，MMSE）判决反馈信道估计算法在多输入多输出正交频分复用（Multiple—input Multiple-output Orthogonal Frequency Division Multiplexing，MIMO—OFDM）低信噪比水声通信环境下存在误码遗传缺陷，提出了一种基于压缩感知理论的改进的MMSE判决反馈信道估计算法。通过结合浅海水声信道的稀疏性特点，利用编码校验后的信息与原始信息实现了对信道估计的判决反馈更新，采用匹配追踪算法改进MMSE判决反馈追踪信道估计技术，实现了抑制传统判决反馈信道估计算法在迭代更新及传递过程中存在的误码遗传的目的。仿真和水池实验结果证实：改进的MMSE判决反馈追踪信道估计算法不仅可以有效的抑制误码遗传，对抗突发噪声，跟踪信道的缓慢时变，同时大幅降低了导频占用率，提高了通信质量。

英文摘要：

To overcome the disadvantage of error propagation, an improved decision feedback channel estimation al- gorithm based on compressed sensing technology is proposed for multiple-input multiple-output orthogonal frequency division multiplexing communication in low signal-to-noise ratio underwater acoustic environment. The corrected and the original information are used to contrive the decision feedback channel estimation. And taking advantage of neritic channel＇s sparse characters, the channels can be constructed by matching pursuit ameliorated minimum mean square error decision feedback channel estimation algorithm without error propagation. Experiment results performed with numerical simulation and tank-trial data are provided, demonstrating that the proposed algorithm can effectively reduce the occupancy of pilots, abate the burst noise effect, offer confined error propagation and significantly increase the quality of the system.