提高近场声全息重建精度方法

The Method of Improving the Reconstruction Accuracy of Near-Field Acoustic Holography

在近场声全息中利用扫描法进行全息面测量时,全息面上的测点信号与参考信号会不可避免地受到一些噪声的影响,降低重建精度,影响重建的实现。在噪声与声源信号以及噪声相互之间非相关的假设下,首先引入两种传递函数估计方法求解全息面复声压,然后再进行近场声全息重建。仿真和实验结果表明,该方法可以有效抑制非相关噪声对全息面复声压计算的影响。近场声全息重建结果表明,该方法减少了测量噪声带来的误差,提高了扫描法近场声全息的重建精度。

In the practical measurement of scanning near-field acoustic holography(NAH),measured signals on holographic grids and reference points are inevitably contaminated by some noises.These noises will be amplified in the process of NAH back reconstruction,and source reconstruction accuracy is degraded.On the assumption that the noises are uncorrelated with each other and the source,two new transfer functions is introduced in NAH to obtain the complex sound pressure on hologram,and then the NAH is implemented.Both numerical and experimental results show that the effects of uncorrelated noises on calculating holographic complex pressure can be suppressed in the proposed method.Furthermore,the reconstruction results show that the error induced by the measurement noise is reduced,and the reconstruction accuracy is improved.