单次快拍波达方向矩阵法

Single snapshot DOA matrix method

提出了一种新的基于阵列系统单次快拍数据的相干信源二维波达方向(direction of arrival,DOA)快速估计方法——单次快拍波达方向矩阵法(single snapshot DOA matrix method,SS-DOAM)。该方法保持了原DOA矩阵法无需二维谱峰搜索和参数配对的优点,利用阵列系统结构特点,构建单次快拍数据矩阵,通过对单次快拍波达方向矩阵进行特征分解,解决了二维DOA估计问题并实现了相干信源完全解相干。由于该算法只利用一次快拍数据,不需要快拍累计和进行相关运算,计算复杂度大幅降低,适用于对二维DOA估计实时性要求高的应用背景。针对单快拍算法在低信噪比时估计误差较大的问题,进一步提出了利用同相数据叠加来改善估计精度的对策。仿真结果证明了该方法的有效性。

Based on one single snapshot from array systems, a novel single snapshot direction of arrival ma- trix method （SS-DOAM） is proposed for estimating two-dimensional DOA （2-D DOA） of coherent signal sources. The algorithm can retain the advantages of the traditional DOA matrix method, such as automatic pa- rameter alignment and no need of 2-D search spectrum peak. Utilizing the characteristics of array systems, the proposed algorithm constitutes data matrices which use the observed data vector directly. The problem of 2-D DOA estimation and decorrelation can be solved via the eigen-decomposition of the single snapshot DOA matrix. Because of using single snapshot, the algorithm does not need correlation calculation and the cumulation of snap- shots, so the complexity of the algorithm is very low, and it can be applicable for high calculation speed scenari- os. Furthermore, the countermeasure for improving estimation accuracy by using in-phase data is discussed. The simulation results show the effectiveness of the method.