基于运动小平台的矢量阵近场强干扰抑制技术研究

Passive detecting sonar based on small moving platforms, UUV, for example, is of significant economic and military value, for its mobility, concealment and the capability to work in extreme and dangerous environment. However, study on reducing the strong near field interference is essential because the self-noise interference resulted from the moving of the platform could cause serious decline in performance of the passive detecing sonar.This project develops the matrix pre-filtering focused beamforming technique, referring to the design idea of bandstop matrix filter in far field plane wave and combining the focused beamforming method based on near field spherical wave assumption. A matrix filter in space domain is designed to preprocess the data of hydrophone array, setting several stop bands in the scope of scanning to shield the strong interference and to ensure the signals pass though distortionlessly as much as possible in other desired areas.The vector beamforming could still be adopted for remote targets passive detection after the data of the array is preprocessed by the matrix pre-filter whose outcome remains the feature of the original data.This project will focuse on discussing the methods and technique of suppressing the strong near field interference effectively and improving the performance of the vector array passive detecting sonar based on small platforms remarkably.

基于UUV等运动小平台的被动探测声纳由于兼具机动性、隐蔽性和可工作于极限或危险作业环境的优点，具有重要的经济和军事价值。但平台运动产生的自噪声干扰会使被动探测声纳的性能严重下降，因此必须研究基于运动小平台的近场强干扰抑制技术。本项目拟借鉴远场平面波中带阻矩阵滤波器的设计思想，结合基于近场球面波假设的聚焦波束形成方法，发展基于矩阵空域预滤波的聚焦波束形成技术。通过设计一个空域的矩阵滤波器对水听器阵列数据进行预处理，在扫描范围内设置多个阻带区，屏蔽该区域内的强干扰信号，且尽量保证其它感兴趣区域内的信号无畸变通过。由于该空域矩阵滤波器的输出保留了阵元域数据的特性，在经过该预滤波器处理后，仍可进行矢量阵波束形成，实现远程目标被动探测。本项目将致力于探讨可有效抑制近场强干扰、显著提高小平台矢量阵被动探测声纳性能的方法和手段。

本课题针对UUV等运动小平台的自噪声干扰抑制问题开展研究，致力于构建可有效抑制近场强干扰、显著提高小平台矢量阵被动探测声纳性能的方法和手段。主要研究工作及进展概括如下：（1）借鉴远场平面波中带阻矩阵滤波器的设计思想，并结合基于近场球面波假设的聚焦波束形成方法，发展了一种基于矩阵空域预滤波的聚焦波束形成方法。（2）通过设计一个空域的矩阵滤波器对水听器阵列数据进行预处理，在扫描范围内设置多个阻带区，屏蔽该区域内的强干扰信号，且尽量保证其它感兴趣区域内的信号无畸变通过。由于该空域矩阵滤波器的输出保留了阵元域数据的特性，在经过该预滤波器处理之后，仍可进行矢量阵波束形成，实现远程目标被动探测。（3）将矩阵滤波算法与波束形成算法结合，构建了一种稳健的鲁棒自适应波束形成算法。该算法的基本思想是：首先根据预定义的感兴趣观测扇面构造一个子空间，并利用该子空间将导向矢量的失配向量分解成两个相互正交的分量，其中之一为失配向量在子空间之内的投影，另一个分量与子空间正交；然后，针对这两部分分量，分别采用子空间约束准则与主瓣畸变最小化约束准则进行搜索，以此来修正导向矢量；最后，利用修正的导向矢量设计自适应波束形成器权系数。将本课题所构建的矩阵滤波方法应用于UUV无人声纳系统之中，可显著提高其被动探测性能，具有重要的经济和军事价值。