可用于快速搜索卫星信号的降维空时波束形成算法  

Improved Reduced-Rank Space-Time Adaptive Processing Beamforming Algorithm for Fast Search of Satellite Signal

作　　者：王立兵[1,2] 韩宁 龚文飞[4] 

机构地区：[1]军械工程学院光学与电子工程系 [2]63961部队 [3]军械技术研究所 [4]北京交通大学电子信息工程学院

出　　处：《南京航空航天大学学报》2013年第3期402-409,共8页Journal of Nanjing University of Aeronautics & Astronautics

摘　　要：针对功率倒置空时抗干扰算法性能低以及传统线性约束空时抗干扰算法运算大的问题,在未知信号来向的前提下,研究了可用于快速搜索卫星信号的降维空时波束形成算法。首先,该算法不需要估计输入数据的协方差矩阵,利用多级嵌套维纳滤波直接对输入数据进行处理,在多级嵌套维纳滤波的前向迭代过程中得到干扰子空间矩阵;其次,对干扰子空间矩阵进行QR分解,求出该矩阵的一组正交基,依据该正交基矩阵,利用最小二乘算法,求出最接近期望信号导向矢量的正交基,作为空时二维最优权值;最后,在搜索不同卫星来向的过程中,仅需要少量乘法运算即可求出最优权值,实现当前方向上卫星信号的搜索。理论分析和仿真结果表明,本文提出的算法的性能远好于功率倒置空时抗干扰算法,虽然性能稍逊于传统约束空时抗干扰算法,但运算量大大降低,可以实现空间中卫星信号的快速搜索。To improve the performance of the anti-jamming method of traditional power inversion space- time adaptive processing and to reduce the computational burden of traditional linearly constrained mini- mum variance space-time adaptive processing（STAP）, an improved reduced-rank space-time adaptive processing beamforming algorithm is proposed for fast search of satellite signal without the direction knowledge of desired satellites. Firstly, in the process of the proposed algorithm, the multistage nested Wiener filter （MSNWF） implemented in the data domain is employed. Then the matrix of interference space can be obtained in the forward recursion of MSNWF. Secondly, a group of orthogonal basis can be calculated. Then the space-time weight vector can be obtained with least square method through the lin- ear combination of orthogonal basis. And the weight vector is closest to the steering vector of the expec- ted satellite signal and deeply depresses the interference signals simultaneously. Finally, the direction of the expected satellite signal can be searched with low computational complexity in calculating the space- time weight vector of one direction. Theory analysis and results of the experiment demonstrate the supe-riority ofthe proposed algorithm.

关 键 词：功率倒置 线性约束空时算法 降维 波束形成 多级嵌套维纳滤波 

分 类 号：TN914.42[电子电信—通信与信息系统]