Reflected acoustic wave suppression method based on the cepstrum clip and its application in noise field reconstruction

In order to suppress the reflected acoustic waves of wide band noise in a narrow and enclosed space, this article introduces a reflected acoustic wave suppression method based on the cepstrum clip. In the proposed method, firstly, the reflected part in the cepstrum of noise is divided by the environmental impulse response duration; secondly, abnormal points in the reflected part are determined by the theory; finally, the abnormal points are assigned to normal values again, thereby the reflected components are suppressed without breaking the direct components of noise. To validate the proposed method, experiments were performed in an ordinary room, which is a weak reflection environment, and in an experimental module, which is a strong reflection environment. Experimental results show that the proposed method can effectively suppress the reflected acoustic waves. The error of sound field reconstruction brought by the reflected acoustic waves is decreased from 90% to 35%, indicating that the proposed method improves the accuracy of sound field reconstruction.