基于近场聚焦波束形成方法的声场定位研究

Research of Sound Field Localization Based on Near-Field Focusing Beamforming

海洋环境中的声场定位,是水声学研究领域中的一个经典问题,尤其是用于海区警戒来监听敌方潜艇的近场定位问题。以往的近场定位研究,通常使用线列阵模型,利用常规聚焦波束形成方法进行定位处理,不仅出现了"左右舷模糊"问题,而且对信号定位不甚理想。为此提出基于半圆阵的四阶累积量MUSIC近场聚焦波束形成算法。通过仿真比较了多种聚焦波束形成在近场线列阵和圆阵条件下的定位性能,结果表明,半圆阵成功地解决了直线阵列出现的"左右舷模糊"问题,基于四阶累积量的MUSIC近场聚焦波束形成可以达到更为平滑的背景以及较小的旁瓣级,定位性能明显优于基于MVDR算法的聚焦波束形成高分辨率被动定位方法。

The sound field localization propagation in the ocean, especially the near - field positioning, is a clas- sical underwater acoustic research problem. Previous studies commonly used the linear array model for the positioning process and used the conventional focusing beamforming method in the near - field positioning, but there is “port and starboard ambiguity” problem, and it is not ideal for the signal positioning. Aim at to solve the above - mentioned problems, by using high - order cumulant and high resolution technology in the near field target beating estimation, a positioning algorithm is put forward based on fourth -order cumulant MUSIC near- field focusing beamforming. The simulation results show that the semi - circular array can solve the “port and starboard ambiguity” problem which ap- pear in the linear array, the focusing beamforming based on fourth - order cumulant MUSIC near - field can achieve the smoother background as well as the smaller side - lobe level, and it＇s positioning performance uis significantly better than the algorithm based on MVDR focused beamforming resolution passive localization method.