摘要
针对共形阵列天线自适应波束形成中存在的主瓣保形困难、旁瓣电平高等问题,该文提出基于波束响应矢量优化的自适应波束形成方法。在主瓣波束保形约束条件下,通过自适应地调整波束响应矢量,求得最优的响应矢量,进而求得准最优自适应权。该方法将非凸的二次约束二阶优化问题转化到高维空间进行求解,并通过半正定松弛(SDR)转化为凸优化问题,高效求得准最优解。该方法不仅保持了期望的主瓣响应,同时克服了传统线性约束最小方差(LCMV)自适应波束形成方法旁瓣高的缺点,并且对阵列构型具有稳健性。仿真实验验证了该方法的有效性。
The mainbeam is difficult to maintain in adaptive beamforming for conformal array, and even worse, the sidelobe is very high. To alleviate these problems, an adaptive beamforming method is proposed based on the response vector optimization. Through adaptively adjusting the response vector under the well-maintained mainbeam constraint, the optimal response vector is derived, thus the sub-optimal adaptive weight is obtained. The proposed method converts the non-convex quadratically constrained quadratic optimizing problem into a higher-dimension subspace, then the problem is transformed into a convex optimization problem via SemiDefinite Relaxation （SDR）, and then its sub-optimal solution is efficiently achieved. The method not only maintains the desired response of the mainbeam, but also overcomes the disadvantages of high sidelobe resulting from the conventional Linearly Constrained Minimum Variance （LCMV） adaptive approach. Moreover, it is robust against the geometry of the array. Simulation results demonstrate the effectiveness of the proposed method.
出处
《电子与信息学报》
EI
CSCD
北大核心
2014年第9期2220-2226,共7页
Journal of Electronics & Information Technology
基金
国家自然科学基金(61072021)资助课题
关键词
阵列天线
响应矢量优化
共形阵
半正定松弛
稳健波束形成
Array antenna
Response vector optimization
Conformal array
SemiDefinite Relaxation （SDR）
Robust beamforming
