Abstract: Adaptive equalization and blind equalization used in underwater acoustic communication and some representative algorithms are briefly introduced. The computer simulations of adaptive and blind algorithms about Mean Square Error（MSE） ability are carried out respectively under sparse multi-paths and mixed phase underwater acoustic channels, the simulation results demonstrate that the algorithms using Decision Feedback Equalizer（DFE） structure have better equalization result in above complex underwater acoustic environment；and then the simulation comparison of some representative adaptive and blind equalization algorithms are carried out under sparse multi-paths phase rotation complex channels, the results show that the affected degree of adaptive equalization algorithm to phase is smaller than that of blind equalization algorithms and the convergence speed of adaptive equalization algorithm is faster than that of blind equalization algorithms. At the same time, the anechoic tank experiment is carried out to verify the performance of algorithms about carrier recovery, the experiments verify that equalization algorithms with second order Digital Phase-Locked Loop（DPLL） and DFE structure have better performance and realize the tracking ability of phase deviation, overcome multi-path effect and improve the compensation ability of Doppler shift.

Key words: underwater acoustic channel, adaptive equalization, blind equalization, decision feedback, Digital Phase-Locked Loop（DPLL）

摘要： 简述了自适应均衡算法和盲均衡算法在水声通信中的应用现状，以及典型的几种均衡算法。分别采用稀疏多径信道和混合相位信道对几种典型的自适应算法和盲均衡算法的均方误差（MSE）性能进行了仿真比较，结果显示，判决反馈均衡器（DFE）结构的算法在以上复杂水声环境中均衡效果良好；采用稀疏多径相位旋转复信道对典型的自适应、盲均衡算法进行了仿真比较，结果表明，在相同的条件下，自适应算法受相位的影响较小，收敛速度快于盲均衡算法。消声水池实验表明了带二阶数字锁相环（DPLL）和DFE结构的均衡算法均具有较好的载波恢复性能，实现了对相位偏差的跟踪，提高了克服多径效应和多普勒频移补偿的能力。

关键词: 水声信道, 自适应均衡, 盲均衡, 判决反馈, 数字锁相环