声矢量阵远程定向技术(一)——新的协方差矩阵生成方法

Acoustic vector sensor array based DOA estimation for long-range targets——Part I :A novel method to construct covariance matrix

MUSIC等子空间类DOA(direction of arrival)估计算法,以其较高的分辨能力和相对较小的计算量而颇受关注．但如果将其简单引用到声矢量阵中,将矢量传感器(AVS)的振速信息仅仅作为独立的阵元来处理,则并没有充分利用AVS 中声压和振速的相干性,以及由此带来的抗各向同性噪声能力．基于AVS中声压和振速的相干性原理,提出了一种新的声矢量阵协方差矩阵牛成方法．该方法完全利用了AVS的平均声强抗噪原理,具有较强的抗各向同性噪声能力,可将子空间类DOA估计方法与声矢量阵技术更为有效地结合起来,实现远程高分辩DOA估计．理论分析和基于湖试数据的仿真实验证明了新方法的有效性．

Subspace based DOA estimation algorithms such as MUSIC, have attracted a lot of attention in recent years due to its high resolution and low computational complexity. In order to apply them to a uniform linear acoustic vector sensor arrays（AVSA） more efficiently, a novel method to construct covariance matrix of AVSA, which is different from the traditional method using particle velocity informations of acoustic vector sensor（ AVS） as an independent array element, is proposed in this paper. The new method is based on principle of the coherency between pressure and particle velocity, has better DOA estimation performance than other methods in isotropic noise field. Both theoretical analysis and computer simulations based on real data show,the proposed method is effective and superior to traditional methods in resolution and the accuracy when signal -to- noise ratio（ SNR）is small.