阵元位置激励联合优化的低旁瓣自适应波束形成

Low Sidelobe Adaptive Beamforming Based on Joint Optimization Position and Excitation of Array Element

传统波束形成仅通过优化阵元激励权值达到设计目标,忽略了阵元位置对波束形成性能的影响。为进一步提高波束形成性能,文中综合考虑阵元位置和激励对波束目标的影响,提出了一种新的低旁瓣自适应波束形成设计方法。该方法分为两步:第一步,在一定阵元孔径和阵元个数下,以低旁瓣波束图的设计目标,采用正交匹配追踪的方法求解阵元位置及激励;第二步,在保留低旁瓣波束图特征的基础上将静态波束激励权值转化为自适应波束激励权值,抑制了强干扰,提高了输出信干噪比。仿真实验证明:在相同的设计目标下,该方法所设计的阵列相比均匀线阵需要更少的阵元个数,节约了硬件开销,同时文中算法综合了低旁瓣静态波束形成与自适应波束形成的优点,提高了阵列增益,增强了算法稳健性。

Traditional beamforming achieves the design goal only by optimizing the excitation weight of array element,ignoring the influence of the position of the array element on the beamforming performance.In order to further improve the beamforming performance,a new low sidelobe adaptive beamforming design method is proposed by comprehensively considering the influence of position and excitation of array element on beam target,which is divided into two steps.In the first step,under a certain aperture and number of array elements,the position and excitation of array elements are optimized by orthogonal matching pursuit method aiming at the design of low sidelobe beam pattern.In the second step,on the basis of retaining the characteristics of low sidelobe beam pattern,the excitation weight of static beamforming is transformed into the excitation weight of adaptive beamforming,which suppresses strong interferences and improves the output signal-to-interference-to-noise ratio.The simulation results show that the array designed by this method needs less array elements than the uniform linear array with the same design goal,which saves the hardware overhead.At the same time,this algorithm combines the advantages of low sidelobe static beamforming and adaptive beamforming,which improves the gain of the array and enhances the robustness of the algorithm.