中文摘要：

水下传感器网络为水下目标的被动定位提供了新的思路，结合水下声信道的传输特性，研究了基于水下分布式传感器网络目标DOA值估计的最大似然被动定位算法。比较了最大似然定位算法在矩形和菱形网络拓扑结构中不同的定位精度，分析了目标不同声源级及网络规模对定位精度的影响，并与线性和非线性最小二乘定位算法的结果进行了对比，其定位精度优于两者。仿真结果验证了定位算法的有效性，所得结论为水下传感器网络进行目标被动定位提供了参考。

英文摘要：

It is a novel way to localize target based on Underwater Sensor Networks. So a passive source localization algorithm based on DOA （Direction of Arrival） for Underwater Sensor Networks was proposed, which adopted the principle of underwater acoustic to generate the localization model Source location was estimated by maximum-likelihood method. The variety of localization precision was analyzed which changed with different network topology, source level and network scale. Moreover, this method was compared with a linear least square and a nonlinear least square through simulation. The localization performance is better than the others. The results of simulation show the algorithm validity, and achieve some applicable conclusion.