基于最大非圆率信号的改进SWEDE算法  

Improved SWEDE for Signals with Maximum Noncircularity Rate

作　　者：赵悦[1] 孙明磊[1] 谢俊好[1] 

机构地区：[1]哈尔滨工业大学电子与信息工程学院,黑龙江哈尔滨150001

出　　处：《信号处理》2011年第5期697-702,共6页Journal of Signal Processing

基　　金：总装预研项目(513210403);全国优秀博士学位论文作者专项资金资助项目(200340)

摘　　要：SWEDE(subspace method without eigendecomposition)算法是一种不需要协方差阵分解的波达方向估计算法。该方法能降低传统超分辨算法的计算量和复杂度,但也同时降低了均匀线性阵的可测最大信号数。本文基于非圆信号具有椭圆协方差矩阵不为零的特征,并结合SWEDE算法的基本思想,提出了一种改进SWEDE算法:NC-SWEDE算法。该算法利用最大非圆率信号的增维数据模型,相当于将线性阵的可利用阵元数加倍,因而提高了SWEDE算法可测的最大信源数,并提高了算法的分辨力和估计精度。由于引入了非圆信号的相位参数,该算法需要进行二维谱峰搜索,本文采用求极值方法达到了降维的目的。本文分别进行了NC-SWEDE算法最大可分辨信号数、不同D矩阵取法下的算法性能及与传统SWEDE算法性能比较的仿真实验,结果验证了该算法的优越性。SWEDE（subspace method without eigendecomposition）algorithm is one kind of DOA（direction of arrival）algorithms. This algorithm doesn＇t need eigenvalue decomposition to obtain the signal subspace and noise subspace,which greatly reduce the computation complexity.However the weakness of this algorithm is to reduce the maximum number of the signals detected by the ULA（Uniform linear array）.This paper proposes an improved SWEDE algorithm：NC-SWEDE algorithm by the combination of the nature of signals with maximum noncircularity rate and SWEDE algorithm.NC-SWEDE algorithm uses the augmented data model of the non-circular signals with maximum rate,which is equivalent to double the number of array elements to increase the maximum number of sources measured by SWEDE algorithm.Originally this algorithm should resort to 2D search for spatial spectrum due to the phase of the non-circular signals.By getting the extremes of the phase,we can reduce dimension and the computation complexity.Several computer simulations are conducted to compare performance of NC-SWEDE with SWEDE algorithm respectively.Simulation results verify that NC-SWEDE algorithm can improve the resolution performance and the estimation accuracy compared with SWEDE algorithm.

关 键 词：阵列信号处理 波达方向 非圆信号 SWEDE算法 

分 类 号：TN953[电子电信—信号与信息处理]