基于实值矩阵的宽带信号DOA估计方法

Wideband Signal DOA Estimation Method Based on Real-Value Matrix

针对传统宽带信号DOA估计算法的高计算复杂度问题,提出使用实值矩阵改进的算法。与传统算法在复数协方差矩阵的基础上进行DOA估计相比,本算法仅使用复数协方差矩阵的虚部构造出一个实值矩阵,并在此实值矩阵的基础上,使用子空间算法进行DOA估计。实值矩阵不仅能够降低特征值分解的计算量,而且得到的噪声子空间与真实DOA和镜像DOA均正交,因此在DOA迭代估计时,仅需要对一半的角度进行谱峰搜索,而对于搜索时出现的角度模糊问题,可通过MUSIC算法去模糊,从而达到正确估计效果。相比于传统宽带信号DOA估计算法,本算法在保持DOA估计精度几乎不变的基础上,有效降低了算法计算量,计算机仿真结果验证了本文算法的有效性。

Aiming at the high computational complexity of traditional wideband signal DOA(direction-of-arrival)estimation algorithm,an improved algorithm using real value matrix is proposed.Compared with the traditional algorithm based on the complex covariance matrix for DOA estimation,the algorithm only uses the imaginary part of the complex covariance matrix to construct a real-valued matrix,and based on the real-valued matrix,the subspace algorithm is used to DOA estimates.The real-valued matrix can reduce the computational complexity of eigenvalue decomposition,and the obtained noise subspace is orthogonal to the real DOA and the mirrored DOA.Therefore,in the DOA iterative estimation,only half of the angle needs to be searched for the peak.The angle ambiguity problem happening in the searching period can be solved by MUSIC algorithm to achieve a correct estimation effect.Compared with the traditional wideband signal DOA estimation algorithm,this algorithm effectively reduces the computational complexity of the algorithm while keeping the DOA estimation accuracy almost unchanged.The computer simulation results verify the effectiveness of the improved algorithm.