基于双水听器的目标深度辨识

Source depth discrimination based on double hydrophones

随着水下目标越来越安静,探测并区分水下目标变得越来越困难。现在对目标的深度辨识多采用匹配场的方法,但其需要大量的先验知识,由于海洋情况多变复杂,这种方法并不适合进行工程实践。本文旨在探索出一种适用于浅海波导的目标深度辨识方法,并减轻工程实践的复杂度。此方法基于Pekeris波导模型,应用了数值仿真技术对垂直双水听器声压互谱的有功分量进行了分析,发现当声源深度变化时互谱有功分量符号随之变化,这个变化规律可以用于目标深度辨识。本文总结了简正波阶数以及水听器深度变化对目标深度辨识结果的影响。通过实验验证,此方法可以较好的对浅海目标进行深度辨识,方法较为可靠,有一定的应用前景。

As underwater targets become more and more quiet, detecting and distinguishing underwater targets become more and more difficult. Nowadays we often use the matched field processing to estimate the depth of a target, but the matched field processing needs a great deal of prior knowledge. Since the complexity of ocean environment, the matched field processing is not suitable for engineering practices. This paper aims to realize a method which can discriminate the depth of shallow water targets, and reduce the complexity of the engineering practice. This method is based on the Pekeris waveguide model, and uses the numerical simulation technology to analyze the active component of double acoustic vertical pressure cross-spectrum. The sign of an active component changes along with the depth of sound source. This can be used to discriminate target depth. This paper has summarized how the normal mode number and the hydrophone depth affect the target depth discrimination. In the lake experiment, this method is excellent for the depth discrimination of shallow water targets. The method is reliable, and has the certain application prospects.