任意阵列双基地MIMO雷达的半实值MUSIC目标DOD和DOA联合估计  

Joint DOD and DOA estimation for bistatic MIMO radar with arbitrary array using semi-real-valued MUSIC

作　　者：张秦[1,2] 张林让[1] 郑桂妹[2] 李兴成[2] 

机构地区：[1]西安电子科技大学雷达信号处理国家重点实验室,陕西西安710071 [2]空军工程大学防空反导学院,陕西西安710051

出　　处：《系统工程与电子技术》2016年第3期532-538,共7页Systems Engineering and Electronics

基　　金：国家自然科学基金(61501504);中国博士后科学基金(2015M581097)资助课题

摘　　要：实值处理具有降低高自由度多输入多输出(multiple-input multiple-output,MIMO)雷达角度估计大计算量的优势。但受制于阵列的共轭对称性,对于任意阵列结构的双基地MIMO雷达发射角(direction of departure,DOD)和接收角(direction of arrival,DOA)联合估计,若不做附加的预处理则无法实现实值操作,故将常规阵列实值处理的多重信号分类(multiple signal classification,MUSIC)超分辨算法推广至任意阵列结构的双基地MIMO雷达。首先根据MIMO雷达的导向矢量共轭与镜像的对等性,提取接收信号协方差矩阵的实部,并对其进行特征分解得到"目标加倍"的信号子空间及其应对的噪声子空间;然后利用Kronecker积的特性对其进行降维处理,得到搜索区域减半的一维半实值域MUSIC谱,取出目标DOD真值与其镜像代入降维Capon算法来剔除虚拟峰值得到目标DOD估计真值;最后利用特征矢量得到模糊DOA估计值,采用方向余弦差最小范数方法得到目标DOA无模糊估计值。本文算法估计性能与一维搜索复数域MUSIC相当,计算量约降50%,且能够实现DOD和DOA的自动配对。仿真结果证明了该算法的有效性。Real-valued domain processing has the advantage of reducing the heavy computational complexity for multiple-input multiple-output（MIMO）radar angle estimation with large degrees of freedom.Unfortunately,real-valued domain processing cannot be applied to bistatic MIMO radar with the arbitrary array structure for direction of departure（DOD）and direction of arrival（DOA）estimation except additional pre-processing because the array do not have the characteristic of conjugate symmetry.Therefore,the multiple signal classification（MUSIC）super resolution algorithm for conventional array with the real-valued domain processing extends to the bistatic MIMO radar with the arbitrary array structure.According to the equivalent characteristic between conjugation and image of the steering vector of MIMO radar,the real part of the received signal covariance matrix is firstly extracted and an eigen-decomposition is performed to obtain the signal subspace with＂double targets＂and its corresponding noise subspace.Then the characteristic of Kronecker product is used to reduce the dimension of the process to achieve one dimensional search MUSIC spectrum in the semi-real-valued domain.The true DOD and its images estimations are substituted into reduced-dimensional Capon spectrum to eliminate the peaks of images.Finally,the eigenvectors are utilized to obtain ambiguous DOA estimations and the minimum norm of the direction-cosines difference method is used to disambiguate the DOA estimations.The proposed algorithm has the similar estimation performance and half computational complexity compared with the one dimensional search complex domain MUSIC algorithm.Moreover,the proposed algorithm can realize auto-matic pairing between DOAs and DODs.Simulation results verify the effectiveness of the proposed algorithm.

关 键 词：半实值多重信号分类 多输入多输出雷达 任意阵列 发射角估计 接收角估计 

分 类 号：TN958[电子电信—信号与信息处理]