基于空间傅里叶变换的平面近场声全息中信噪比估计方法研究

The Estimation of the Signal-to-noise Ratio in the Planar Nearfield Acoustic Holography Based on the Spatial Fourier Transform

在近场声全息技术中，信噪比是一个非常重要的参数，但无法直接测量。为解决此问题，给出了基于空间傅里叶变换的平面近场声全息中两种可靠的信噪比估计方法：能量法信噪比估计和幅值法信噪比估计；其中能量法信噪比估计更精确，而幅值法信噪比估计更简单。采用两种方法进行信噪比估计，都可以得到较真实的信噪比结果。数值仿真和实验结果验证了两种方法的正确性和适用性。

The signal to noise ratio （SNR） is a very important parameter in the planar nearfield acoustic holography （NAH）. However, it can not be measured directly by laboratory apparatus. Through the analysis of the NAH process, two estimated methods for planar NAH based on the spatial Fourier transform are given. One is the energy estimated method, the other is the amplitude estimated method. A truthful SNR value could be estimated by those two methods, and the reconstruction error is reduced. The validity and applicability of the proposed research are proved by the numerical simulations and the experiment.