基于二阶锥规划的相干信号宽零陷自适应波束形成

摘要

针对传统自适应波束形成器在相干干扰位置出现快速变化时，输出性能下降，甚至干扰抑制失效的问题，提出了一种基于二阶锥规划(SOCP)的相干信号宽零陷自适应波束形成算法。该算法首先对接收数据协方差矩阵进行Toeplitz重构，然后重构了干扰加噪声协方差矩阵并对其进行零陷展宽处理；接着在保证期望方向波束无失真前提下，约束主瓣宽度和旁瓣电平，使得波束形成器干扰和噪声的输出功率最小；最后将该问题转化为凸优化中的二阶锥规划问题，并使用凸优化工具箱进行快速求解。仿真实验表明，该算法可以在兼顾全部阵列性能指标的前提下，在相干干扰区域形成宽零陷。%Because the traditional adaptive beamformer suffers from the output performance degradation and e-ven interference suppression failure when the position of the coherent interference moves,a adaptive beam-form-ing of coherent signals with null widening based on second order cone programming (SOCP)was proposed. Firstly,the algorithm formed a Toeplitz matrix based on covariance matrix of received data.Secondly,the inter-ference-plus-noise covariance matrix was reconstructed and optimized,and null widening technique was used in the covariance matrix.Thirdly,the optimum beamforming was designed with this method according to the rule of minimizing the beamformer’s output power of interferences and noise while keeping the distortionless re-sponse in the direction of desired signal and keeping constant side-lobe level and beamwidth.At last,the original problem was translated into SOCP problem,which could be solved effectively via convex optimization toolbox. Simulation results showed that the proposed algorithm could form a wide null in the strong coherent interference position under the premise of taking all the performance of array into account .