浅海中水平线列阵深度对匹配场定位性能的影响

以浅海声传播模型为基础，通过计算机仿真观察到以下物理现象：浅海中海底水平线列阵的匹配场定位性能优于其他深度水平线列阵.利用简正波建模方法揭示了这一现象的物理机理.按照简正波理论，各号模式的形状是海水深度的函数.通过比较不同深度上各号模式幅度的变化，发现海底模式幅值接近零的模式号数明显小于其他深度.这说明海底水平线列阵可以对更多号模式进行采样，进而获得更多的目标声源信息，取得更好的匹配场定位效果. 关键词： 水平线列阵 匹配场定位 基阵深度

The performance of matched-field localization with a horizontal line array at different depths in shallow water

The performance of matched-field localization with a horizontal line array (HLA) at different depths in shallow water is investigated by normal mode modeling and computer simulation. It is observed that the matched-field localization performance of a bottom-mounted HLA is better than that of a HLA at other depths in shallow water. The normal mode modeling is used to explain this result. According to the normal mode theory, the mode shape is a function of water depth. The absolute values of the modes at different depths are compared. It is shown that the number of modes whose absolute values close to zero is smaller at the bottom than at other depths. It means that the HLA deployed at the bottom can sample more modes，obtain more information of the source and achieve better localization performance.