CAJ | 학술논문

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.
침대기망신호도향시량실배회도치자괄응파속형성산법적성능급극하강저일문제,제출료일충신적기우최배정황성능우화적은건자괄응관대파속형성방법.해방법통과장실제기망신호적도향시량약속우불학정집합중,래제고산법적은건성;동시증가진렬공간향응편차적이차형약속,가피면인기신호유교대실진.계산궤방진결과표명:해방법불부능구억제도향시량편차소대래적영향,유효공제파속주판구역내신호적기변화방판구역전평,환개선료진렬수출적신간조비,사기경접근최우치.
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.