A Study of Subsidiary Source Image Reduction in Acoustic Double Holography Method.

Abstract

A sound source identification technique based on the acoustic double holography method was proposed in the previous paper. This method can achieve high resolution in sound source identification compared with the acoustic holography method. Furthermore, this method is more convenient than the nearfield acoustic holography method for measurement and calculation. However, this method still has the problem that comparatively high-level subsidiary source images appeared in the reconstructed image patterns which might have caused misjudgment. In this paper, a specific zone filtering technique applied to reconstructive calculation for reducing the subsidiary source image is proposed. By this technique, the level of subsidiary source image can be reduced without decrease in resolution of a real noise source image. Finally, in order to examine the effectiveness of the filtering technique, computer simulation and experimentation are carried out.