论文部分内容阅读
自适应波束形成在弱目标检测和空域滤波中应用广泛。然而在实际海洋环境中,失配情况比较普遍,往往会导致传统自适应波束形成方法性能明显下降。针对此问题,本文基于特征分析重构观测信号协方差矩阵来抑制干扰对弱目标检测的影响,在此基础上进一步利用凸优化算法来提高波束形成方法的鲁棒性。数值仿真和海试数据处理结果表明,本文所提方法在抑制干扰对弱目标影响的基础上,在阵元位置平均误差不超过入射信号中心频率对应波长的40%的情况下,仍可以鲁棒地检测目标信号。同时,该方法显著提高了自适应波束形成方法的输出信干噪比,且受对角加载量取值的影响较小。
Adaptive beamforming is widely used in weak target detection and spatial filtering. However, in real marine environment, the mismatch situation is relatively common, which often results in the obvious drop of the performance of the traditional adaptive beamforming method. In order to solve this problem, the paper reconstructs the observed signal covariance matrix based on the feature analysis to suppress the influence of interference on the weak target detection. Based on this, the convex optimization algorithm is further used to improve the robustness of the beamforming method. Numerical simulation and sea trial data processing results show that the proposed method can be robust under the condition of suppressing the influence of interference on weak targets and the average error of array element position does not exceed 40% of the corresponding wavelength of the incident signal center frequency To detect the target signal. At the same time, the proposed method significantly improves the output SINR of the adaptive beamforming method and is less affected by the value of the diagonal loading.