无需预延迟补偿的宽带Frost波束形成算法

Wideband Frost Beamforming without Pre-Steering Delays

针对宽带Frost波束形成算法存在预延迟补偿误差时性能急剧下降的问题,提出一种无需预延迟补偿的宽带Frost波束形成算法。该算法利用离散空间响应变化约束,将带宽内不同频点的一组约束条件改写为参考频点的单个约束条件,有效简化了宽带LCMV算法约束矩阵的设计,推导出最优权系数的闭式表达式,实现宽带恒定束宽波束形成。仿真实验与理论分析表明,该算法无需预延迟补偿,恒定束宽特性较好,旁瓣较低且具有较高的输出信干噪比。

Any error in implementing pre-steering delays will drastically degrade the performance of wideband beamformers. To resolve this problem, a novel wideband Frost beamforming algorithm is proposed without pre-steering delays. Starting with constant beamwidth, a group of constraints imposed on the sampled frequency points can be replaced by one single constraint at a reference sampled frequency point, and a simple design of constraint matrix can be obtained. Then, a close-form expression of weight vector optimization has been presented and the wideband constant beamwidth beamforming can be achieved. The simulations illustrate that the proposed method has the lower sidelobe level, the higher output SINR, and the beampattern with constant beamwidth can be obtained.