Reduction Effects of Correlated Measurement Noise in Near-field Acoustic Holography Based on Bispectrum

In the practical measurement of near-field acoustic holography (NAH), measured signals on holographic grids and reference point are inevitably contaminated by some noises. These noises will be amplified in the process of NAH back reconstruction, and source reconstruction accuracy degrades. As we can assumed that the measurement noise obeys Gaussian distribution, a method based on bispectrum is presented in this paper to overcome the shortage of convention cross spectrum based NAH. The point source model simulation shows that the influence of Gaussian correlated noise can be removed effectively, and the reconstruction accuracy is improved