①Key Lab of Mobile Communications, Chongqing University of Posts and Telecommunications, Chongqing 400065, China; ②School of Communication and Information Engineering, University of Electronic Science and Technology of China, Chengdu 610054, China; ③School of Automation Engineering, University of Electronic Science and Technology of China, Chengdu 610054, China
Abstract：In environment with coherent interferences, performance of adaptive array will decline dramatically, and the general solution is spatial smoothing. However, adaptive array utilizing conventional Uniform Spatial Smoothing (USS) has poor ability to suppress coherent interferences, and it will lose the aperture of array. In the paper, an improved approach to suppress coherent interferences is proposed. Firstly, the paper presents an adaptive Weighted-Spatial-Smoothing (WSS) algorithm, which, through weighted averaging of the correlation matrices of each sub-array, can de-correlate the coherent interferences effectively. And then, based on WSS, using the Linear-Constrained-Minimum-Variance (LCMV) criterion, the optimal weight vector of sub-array beamformer can be obtained. Finally, considering the phase relationship of each sub-array, an approach for full array beamforming is proposed. The approach highly improvs the array’s ability to suppress the coherent interferences, and avoids the loss of aperture caused by conventional spatial smoothing. Theoretical analysis and computer simulation confirm the availability and robustness of the algorithm.
2007, Vol. 29 
