基于虚拟时间反转镜的噪声源近场定位方法研究

通过辐射噪声源的空间分布，确定主要噪声源的位置，从而为减震降噪提供有力依据。在近场条件下，辐射噪声源往往不可再被视为点源处理。本文通过聚焦波束形成的聚焦声图技术，建立了近场线列阵定位模型，它可以对空间多目标进行定位，因此有效解决了非点源目标的辐射噪声源定位问题。在浅海，水声信道可看作是相干多途信道，由于多途的影响，声图很容易出现“多峰”“伪峰”以及高的旁瓣级，使定位性能受到很大影响。本文采用虚拟时‘间反转镜技术，充分利用近场条件下信道特征与各信源到基阵相对位置之间的关系，有效对非点源目标的信道进行准确估计，并能良好匹配实际信道。最后通过仿真和实测数据分析，充分验证了这种方法的有效性。

Radiated Noise Sources Near-field Location Based on Virtual Time Reversal Mirror

The location of major noise source can be determined by noise source spacial distribution im?age to provide powerful basis for damping and denoismg. For radiated noise source can not be treated as point source in near-field, the locating model of line array was established by the sound image tech?nique based on focused beamforming to solve the location of non-point source. In the shallow sea, due to the influence of multi-path, the false peaks, multi peaks and high side lobe are appeared, which make the locating result seriously. The channel of non-point source target was precisely estimated and matched with the actual channel by the virtual time reversal mirror (VlRM) which can fully use the relation between the channel characteristic and the relative position of both the sources and the receiv?ing arrays. The analysis of both simulation and test data results proved the method to be valid.