未知互耦条件下相干与非相干混合信号的波达方向估计  

Direction-of-Arrival Estimation of Coherent and Noncoherent Mixed Signals Under Unknown Mutual Coupling

作　　者：毛维平 李国林[2] 谢鑫[2] 

机构地区：[1]海军装备部驻重庆地区军事代表局,四川绵阳621900 [2]海军航空工程学院七系,山东烟台264001

出　　处：《上海交通大学学报》2015年第10期1558-1563,共6页Journal of Shanghai Jiaotong University

基　　金：国家自然科学基金项目(61102165)资助

摘　　要：针对阵列互耦对导向矢量的扰动,以及信号相干性对数据协方差矩阵造成的秩损致使超分辨波达方向(DOA)估计算法性能变差甚至失效的问题,提出了一种在相干与非相干信号混合状态下无需阵列互耦补偿的DOA估计算法.其中:仅截取部分阵元的接收数据,即可达到阵列互耦自抑制的目的;对数据协方差矩阵进行特征分解,利用所得特征矢量重构等效协方差矩阵,并对等效协方差矩阵进行奇异值分解,基于多重信号分类法或信号参数估计的旋转不变子空间技术完成混合信号的DOA估计;并利用计算机进行数值仿真以验证算法的有效性.结果表明,在阵列互耦未知的条件下,所提出的算法能够正确估计信号的DOA,无需互耦参数的估计或补偿.The performance of high resolution direction-of-arrival（DOA）estimation based on the orthogonality of subspaces is degraded by array manifold perturbation resulted from mutual coupling（MC）and rank loss of covariance matrix caused by the coherency of the signal.In this paper,a direction finding method,without any compensation,was proposed for coherent and non-coherent mixed signals in the presence of unknown MC.The method automatically suppressed the effect of unknown MC by calculating the covariance matrix with part of the received data.Then,an equivalent covariance matrix was reconstructed with the eigenvectors gained by eigen-decomposition of the covariance matrix.By performing the singular value decomposition（SVD）of the equivalent covariance matrix,the DOA of mixed signals could be estimated via MUSIC or ESPRIT algorithms.The proposed algorithm improved the conventional SVD method in order to estimating the DOA of coherent and noncoherent mixed signals.Without any array calibration,the algorithm achieves a favourable accuracy of DOA estimation under unknown MC.The simulation re-sults demonstrate the validity of the proposed method.

关 键 词：阵列信号处理 波达方向 相干 互耦 

分 类 号：TN911.23[电子电信—通信与信息系统]