稀疏阵列方向不变恒定束宽波束形成优化方法

Optimization Method of Sparse Array Steering-invariant Constant Beamwidth Beamforming

为减少实际阵元数目并保证不同指向角对应的波束主瓣宽度保持恒定,提出一种基于压缩感知(com-pressive sensing,CS)和二阶锥规划(second order cone programming,SOCP)的方向不变波束形成(stcering-invariant beamforming,SIB)优化方法。运用CS恢复算法对阵列虚拟拓展后的稀疏阵列采集到的压缩测量信号进行恢复并计算其虚拟加权矢量。通过虚拟加权矢量设计参考波束,采用设计波束主瓣与参数波束主瓣均方误差最小条件下保证设计波束旁瓣水平最低的准则,基于SOCP方法进行方向不变波束形成优化设计。实验结果表明,提出的方法在保证方向不变恒定束宽波束形成性能的同时,减少了实际阵元数目。

;In order to reduce the number of actual array elements and keep the mainlobe width of beam corresponding to different pointing angles constant,a steering-invariant beamforming(SIB)optimization method based on compressed sensing(CS)and second-order cone programming(SOCP)is proposed.Use CS recovery algorithm to recover the com-pression measurement signals collected by the sparse array after virtual expansion of array and ealculate its virtual weigh-ted vector.The virtual weighted vector is used to design reference beam,the criterion of minimizing the designed beam sidelobe level under the condition of the minimum mainlobe mean square error between the designed beam and the reference beam is adopted,and the SOCP method is used to optimize the design of SIB.The experimental results show that the proposed method can reduce the number of array elements while ensuring the performance of steering-invariant constant beamwidth beamforming.