有限快拍下的小尺度矢量阵DOA算法

针对小尺度矢量水听器阵条件下ESPRIT算法目标方位估计精度低、多目标分辨能力弱的缺点,提出了一种基于酉变换的DOA改进算法.该方法无需计算观测数据的协方差矩阵,利用阵列的观测数据及共轭信息构造一中心Hermitian对称矩阵,根据酉变换原理将其转化为实数矩阵并用实值ESPRIT方法估计目标方位.由于利用了观测数据的共轭信息,相当于虚拟增加了阵元个数,改进算法有更高的DOA估计精度和多目标分辨能力,在快拍数与阵元数相当时改进算法比协方差方法有更小的计算复杂度.仿真分析结果证明了算法的有效性.

A DOA Estimation Algorithm Suitable to Small Vector Hydrophone Array with Finite Snapshots

Direction-Of-Arrival(DOA) estimation accuracy and resolution of ESPRIT algorithm are low when the array’s scale is small.An improved algorithm based on unitary transformation and the conjugate data is proposed.By taking use of the conjugate data of the vector hydrophone array’s output,a centro-Hermitian complex matrix can be gotten.Then,unitary transformation is employed to transform the complex matrix into real.Instead of calculating the covariance matrix,the real matrix is used to estimate the DOA directly through ESPRIT method.By using the conjugate data and unitary transformation,the new algorithm has a higher DOA estimation accuracy and resolution.Even when the snapshot number is comparable to the array elements,the improved algorithm has a smaller computational complexity compared to the covariance method.The simulations prove the effectiveness of the algorithm.