BAI Xingyu¹  YANG Desen²  ZHAO Chunhui¹

(1  College of Information & Communication Engineering, Harbin Engineering University  Harbin  150001)

(2  School of Underwater Acoustic Engineering, Harbin Engineering University  Harbin  150001)

Received Jan. 17, 2006

Revised Mar. 8, 2006

Abstract  In order to solve the problem of DOA (Direction of Arrival) estimation of underwater distant wideband targets, a novel coherent signal-subspace method based on the cross spectral matrix of pressure and particle velocity using the Acoustic Vector Sensor Array (AVSA) is proposed in this paper. The proposed method is different from existing AVSA based DOA estimation methods in using particle velocity information of Acoustic Vector Sensor (AVS) as an independent array element. It is entirely based on the combined information processing of pressure and particle velocity, namely, the P-V cross spectrum, has better DOA estimation performance than existing methods in isotropic noise field. By theoretical analysis, both focusing principle and eigendecomposition theory based on the P-V cross spectral matrix are given. At the same time, the corresponding criteria for source number detection is also presented. Computer simulations with data from lake trials demonstrate that the proposed method is effective and obviously outperforms existing methods in resolution and accuracy in the case of low Signal-to-Noise Ratio (SNR).

PACS number: 43.30, 43.60