摘要
针对期望信号导向矢量失配时传统宽带波束形成器性能恶化的问题,提出一种稳健的宽带恒定束宽波束形成算法。首先结合空间响应变化(Spatial response variation,SRV)约束,将算法在信号带宽内不同频点的阵列响应约束简化为对某一参考频点的约束,实现具有恒定束宽特性的宽带波束形成,再通过对权矢量模值施加二次不等式约束,抑制指向误差及传感器参数随机扰动误差,提高算法的稳健性,并通过拉格朗日乘子法,在约束边界上求得最优权矢量的解析解。实验结果表明算法可有效克服信号指向误差引起的波束形成器性能恶化问题,且具有良好的恒定束宽特性及较高的阵列输出性能。
A robust wideband constant beamwidth beamforming algorithm is proposed to solve the prob- lem of performance degrade of traditional wideband beamforminers when there exists steering vector er- ror. With the spatial response variation （SRV） constrain, a wideband constant beamwidth beamforming algorithm can be obtained by simplifying the response at different frequencies as a reference frequency. Then the robustness of beamformer can be improved by imposing the quadratic constraint for the weight vector. Finally, the optimal weight with a closed form can be solved on the boundary of uncertainty set using the Lagrangian method. Experiments illustrate that the algorithm obtains a desired result to against the look direction estimation error, and achieves a preferable constant beamwidth performance and a high output signal to interference plus noise ratio.
出处
《数据采集与处理》
CSCD
北大核心
2016年第4期815-822,共8页
Journal of Data Acquisition and Processing
基金
国家高技术研究发展计划("八六三"计划)(2011AA7031015)资助项目
关键词
宽带波束形成
稳健性
恒定束宽
空间响应变化约束
二次型约束
wideband beamforming
robustness
constant beamwidth
spatial response variation（SRV） constrain
quadratic constraint
