平面阵列下的二维角度和频率联合估计

摘要

在均匀面阵列结构基础上提出一种二维角度和频率联合估计新方法.对阵列天线输出的信号进行建模分析,表明阵列接收信号具有平行因子四线性模型特征.利用该模型低秩分解的唯一性条件,从分解得到的矩阵中联合估计出信源的参数.该算法首先利用四线性交替最小二乘算法估计出方向矩阵和频率矩阵,然后利用频率矩阵的Vandermonde特征和方向矩阵的结构特点及最小二乘法计算频率和二维角度.该方法无需谱峰搜索即可实现参数同时估计与配对,与现有的基于三线性分解的算法和ESPRIT算法相比具有更高的估计精度,而且在小样本数情况下也能较好地工作.仿真结果验证了该方法的有效性.%A novel joint two-dimensional angle and frequency estimation method based on a uniform square array is presented. The output signal of the antenna array is analyzed, showing quadrilinear model characteristics. The source parameters can be estimated from the matrices via low-rank decomposition based on uniqueness of PARAFAC decomposition. The algorithm first uses the quadrilinear alternating least square (QALS) algorithm to estimate the direction and frequency matrices. It then estimates frequencies according to Vandermonde characteristics of frequency matrix and least square principle. DOAs are estimated from the characteristics of direction matrix and the least square principle. The method does not need to search spectral peaks or parameter pairs. Compared with ESPRIT and the trilinear model, the proposed algorithm has high precision in parameter estimation, and works well with small sizes. Simulation results verify its effectiveness.