基于凸优化的时域宽带旁瓣控制自适应波束形成

Convex optimization based adaptive broadband FIR beamforming with sidelobe control

提出了基于凸优化的时域宽带旁瓣控制自适应波束形成方法。首先将基阵波束响应表达成一组FIR滤波器系数的线性函数,然后采用如下的优化准则来设计FIR滤波器组:在保证波束形成器对期望方向信号无失真输出且波束旁瓣低于设定值的条件下,使波束输出功率最小化。同时通过对滤波器系数的范数进行约束来保证波束形成器的稳健性。该波束形成器设计问题被表述成二阶锥规划的凸优化问题来求解。仿真结果验证了所提出方法的有效性。

An approach to time-domain broadband beamforming with sidelobe control is proposed. The array response is expressed as a linear function of the finite impulse response （FIR） filters tap weights. The filters are designed by minimizing array output power while maintaining the distortionless response in the direction of the desired signal and guaranteeing the sidelobes to be below some given threshold values. Norm constraint on tap weights is also imposed to improve the robustness of the beamformer. Computationally efficient convex formulation for the beamformer design problem is derived using second-order cone programming （SOCP）. Simulation results demonstrate the satisfactory performance of the proposed approach.