基于稀疏表示的OFDM信号的DOA估计

针对正交频分复用（OFDM）, 宽带信号波达方向(DOA)估计问题, 提出一种基于宽带信号协方差矩阵稀疏表示的DOA估计方法。该方法是在协方差矩阵主对角线下对左下角三角形元素按各条对角线取平均值后形成一个新的向量, 然后将该向量写成冗余字典形式。在冗余字典下对信号进行稀疏性约束形成二阶锥约束优化问题, 再用工具箱SeDuMi来实现DOA估计。理论分析和仿真结果表明, 该方法在低信噪比和少快拍数下分辨率很高, 是一种有效的宽带信号DOA估计算法, 此方法优于基于高阶累积量算法和宽带聚焦算法的DOA估计方法。

DOA estimation of OFDM signal based on sparse representation

In order to solve the problem of the OFDM broadband signal processing, this paper introduced a algorithm for the direction of arrival (DOA) estimation of OFDM signal based on the wideband signal covariance matrix sparse representation. It averaged the triangle elements in the lower left corner of the main diagonal of the covariance matrix to form a new vector, and wrote the vector in the form of a redundant dictionary. The signal in a redundant dictionary the sparsity constraints formed a second-order cone constrained optimization problems, and then used toolbox SeDuMi to do DOA estimation. Theoretical analysis and simulation results show that the proposed method is an effective wideband signal DOA estimation algorithm and has high resolution in low signal-to-noise ratio and less number of snapshots, it is better than higher order cumulant algorithm and wideband focused matrix algorithm DOA estimation method.