摘要
针对期望信号导向矢量失配会导致自适应波束形成算法的性能急剧下降这一问题,提出了一种新的基于最坏情况性能优化的稳健自适应宽带波束形成方法。该方法通过将实际期望信号的导向矢量约束于不确定集合中,来提高算法的稳健性;同时增加阵列空间响应偏差的二次型约束,可避免引起信号有较大失真。计算机仿真结果表明:该方法不仅能够抑制导向矢量偏差所带来的影响,有效控制波束主瓣区域内信号的畸变和旁瓣区域电平,还改善了阵列输出的信干噪比,使其更接近最优值。
The performance of adaptive beamforming algorithms is known to undergo substantial degradation in the presence of even slight mismatches between the actual and presumed steering vector to the desired signal. To account for mismatches, a novel robust adaptive broadband beamforming algorithm based on worst-case performance optimization is proposed. For the proposed robust beamformer under the uncertainty set constraint of the steering vector, its weight vector is optimized to involve minimization of a quadratic function subject to the amplitude constraint of the averaged spatial response variation （SRV） in the mainlobe and the sidelobe. Respectively computer simulation results demonstrate that the proposed beam former can obtain the prescribed robustness against steering vector errors, suffer the least distortion from the directions near the steering angle, suppress the sidelobe level and make the output signal-to-interference-plus-noise ratio （SINR） closer to the optimal one.
出处
《电路与系统学报》
CSCD
北大核心
2012年第6期76-83,共8页
Journal of Circuits and Systems
关键词
稳健自适应
宽带波束形成
导向矢量失配
最坏情况性能优化
二阶锥规划
robust adaptive
broadband beamforming
steering vector mismatch
worst case performance optimization
spatialresponse variation
second order cone programming （SOCP）
