压缩感知等效源法对板件近场重构精度改进的研究

Improvement of Near-field Reconstruction Accuracy of Plate Using Compressed Sensing Equivalent Source Method

为改进目前板件压缩感知等效源法近场声全息中存在的稀疏基稀疏度不足、适用范围小等问题,提出一种优化等效源面范围的方法。使用板件振动模态与声辐射模态对板件倏逝波分布区域进行联合研究。利用板件振动模态得到高波数倏逝波分布情况,结合声辐射模态得到等效源向量在波数域分布情况,提出减小等效源范围从而达到过滤高波数倏逝波,减小重建误差的效果。数值模拟实验结果表明,该方法增加了等效源向量的稀疏度,对重建精度有大幅度的改善作用,扩大了压缩感知等效源法的使用范围。

In order to improve the existing problems in the compressed sensing equivalent source method for plates nearfield acoustic holography such as insufficient sparsity,small scope of application,a method of optimizing the range of equivalent source surface to filter the high wavenumber evanescent wave is proposed and the reconstruction error reduces.In this method,the plate vibration mode and the acoustic radiation mode are used to study the evanescent wave distribution area of the plate.The high wavenumber evanescent wave distribution is obtained by using the plate vibration mode,and the distribution of the equivalent source vector in the wavenumber domain is obtained by the acoustic radiation mode.The numerical simulation experimental results show that the present method increases the sparsity of the equivalent source vector,improves the reconstruction accuracy greatly and expands the application scope of compressed equivalent source method.