一种相干分布源中心DOA快速跟踪算法  

A Fast Algorithm for the Central DOA Tracking of Coherently Distributed Sources

作　　者：郑植[1,2] 李广军[1] 

机构地区：[1]电子科技大学通信与信息工程学院,四川成都611731 [2]电子科技大学电子科学技术研究院,四川成都611731

出　　处：《信号处理》2011年第4期529-533,共5页Journal of Signal Processing

基　　金：国家自然科学基金资助项目(No.60971081);中央高校基本科研业务费专项资金资助(No.ZYGX2009J092)

摘　　要：在智能天线和无线定位等技术中,精确跟踪目标的波达方向(DOA)十分重要。大多数传统的DOA跟踪方法都将目标信号看成是点源。但在密集的移动通讯环境中,信号的多径散射将引起信号能量的扩散,采用分布式信源模型更适合。因此,研究分布源的DOA跟踪技术更有意义和价值。针对相干分布源,本文基于均匀线阵提出了一种中心DOA快速跟踪算法。该算法首先通过正交紧缩近似投影子空间跟踪(OPASTD)算法实时更新信号子空间,然后利用一种低复杂度的方法估计分布源的中心DOA。本文算法避免了对样本协方差矩阵进行重复的特征分解,计算复杂度较低。算法的跟踪性能良好,并能有效跟踪多个分布源。此外,算法不需要分布源角分布形式的先验知识,稳健性好。仿真结果证实了算法的有效性。In some techniques,such as smart antenna and wireless location etc.,it is very important to track accurately the direction -of-arrival（DOA） of aim signal.Most conventional DOA tracking algorithms are based on the assumption that the aim signal is point sources.However,in dense mobile communication environments,signal multipath scattering will result in angular spreading of the source energy,a distributed source model may be more appropriate.Hence,it is more significant and valuable to research the DOA tracking technique of distributed sources.Aiming at coherently distributed sources,this paper presents a fast algorithm for the central DOA tracking by using uniform linear arrays（ULA）.The presented algorithm firstly updates the signal subspace in real-time by adopting the orthonormal projection approximation subspace tracking with deflation（OPASTD） algorithm,and then a low-complexity DOA method is used to estimate the central DOA of distributed sources.The algorithm avoids the decompositions of the sample eovariance matrix which must be repeated in the classical DOA estimation algorithms and has lower computational complexity,and it provides excellent tracking performance and can track effectively multiple sources.In addition,without the prior knowledge about the angular distribution shapes of distributed sources,the robustness of our algorithm is good.Simulation results validated the efficiency of the presented algorithm.

关 键 词：分布式信号源 波达方向跟踪 均匀线阵 正交紧缩近似投影子空间跟踪算法 

分 类 号：TN911.7[电子电信—通信与信息系统]