声场重构中消除鬼影和提高重构精度的方法

摘要

The ghost images can occur easily in the reconstruction of acoustic fields with the use of beamforming algorithm, which leads to a terrible difficulty for accurate identification of the reconstructed acoustic fields. After detailed deduction of the beamforming algorithm, the relation between the shape parameters of microphone array and the ghost-images occurrence was obtained, and the method for eliminating the ghost images were attained. It was found that after the elimination of ghost images, the reconstruction precision would be improved if the value of D/λwas increased by means of optimization design of the array’s configuration. Finally, the effectiveness and feasibility of this method was verified by some experiments of acoustic-field reconstruction of some pure sound and narrow-band noises.%在利用波束形成算法进行声场重构时，容易出现鬼影现象，给重构声场的准确辨识带来极大困难。在对波束形成算法进行理论推导后，获得麦克风阵列的结构参数与鬼影产生的关系，进而获得消除鬼影的方法；并在此基础上，优化麦克风阵列的布局形式，设计阵列的最大孔径比，可以有效提高重构精度。通过纯音实验和窄带噪声实验，验证了消除鬼影和提高声场重构精度方法的有效性。