Theoretical and experimental investigation of holographic reconstruction and prediction of multi-source hybrid acoustic field

Study on a multi-source hybrid acoustic field is very important for nearfield acoustic holography (NAH) to be applied in the practical engineering field. In this paper, two methods based on the distributed source boundary point method (DSBPM) for holographic reconstruction and prediction of multi-source hybrid acoustic field, namely combination method with single surface measurement and combination method with multi-surface measurement, are proposed. Then, an experiment on two coherent speakers is carried out. By comparison of the reconstructed and predicted results and the actual measured results, the validity of the two methods and the superiority of the combination method with multi-surface measurement are proved. Considering the high sensitivity of the reconstructed results to measurement errors, the Tikhonov regularization method is proposed to stabilize the reconstruction procedure and restrict the influence of errors. And then, the optimal reconstructed results can be obtained and the reliability of holographic reconstruction and prediction is assured.