基于非圆信号的互质阵列欠定DOA估计方法

针对欠定波达方向（direction of arrival，DOA）估计问题，研究了一种基于非圆信号的互质阵列DOA估计方法.对互质阵列输出互协方差矩阵和椭圆协方差矩阵进行向量化处理，通过数据重新链接并去冗余得到一个虚拟均匀线阵输出数据，实现阵列的充分扩展且扩展后的虚拟阵元进一步得到增加；结合入射信号的空域稀疏性，在连续角度域将DOA估计问题转化为一个连续稀疏重构问题，有效避免了传统稀疏重构算法中由于角度域离散化所导致的基不匹配问题对估计性能的影响；通过求解相应的凸优化问题以及多项式求根实现DOA的估计.理论分析和仿真结果表明，该方法具有阵列扩展能力强、估计精度和分辨性能高等优良性能. 

Underdetermined DOA Estimation for Coprime Array Based on Noncircular Signal

For underdetermined direction of arrival (DOA)estimation problems,a novel DOA estimation method was proposed for coprime array based on noncircular signals.Firstly,the cross covariance and elliptic covariance matrix of the coprime array output were vectorized,a virtual uniform array output was formed by reconnecting the data and wiping off the redundancy, making array aperture full expanded and the number of virtual array elements further increased. Then,according to the spatial sparsity of the incident signals,the DOA estimation problem was transformed into a continuous sparse recovery problem in continuous angle region,so as to eliminate the basis mismatch due to angle region discretizing with traditional sparse recovery arithmetic.Finally,the correlative convex optimization and polynomial root were solved to carry out the estimation of DOA.Theoretical analysis and simulation results show that,the proposed method can achieve excellent array expanding,high estimation accuracy and resolution capability.