基于机载多通道雷达迭代超分辨估计的前视成像  

Forward-looking Imaging via Iterative Super-resolution Estimation in Airborne Multi-channel Radar

作　　者：任凌云 吴迪[1] 朱岱寅[1] 孙伟杰 REN Lingyun;WU Di;ZHU Daiyin;SUN Weijie(College of Electronic Information Engineering,Nanjing University of Aeronautics and Astronautics,Nanjing 211106,China)

机构地区：[1]南京航空航天大学电子信息工程学院,南京211106

出　　处：《雷达学报（中英文）》2023年第6期1166-1178,共13页Journal of Radars

基　　金：国家自然科学基金(62271252)。

摘　　要：波达角估计算法用于机载多通道雷达前视成像时可以突破瑞利极限,实现同一波束主瓣宽度内的多目标分辨,改善成像的方位向分辨率,然而天线波束覆盖有限且其快速扫描使得可用于协方差矩阵估计的数据样本缺乏,导致对目标位置和幅度估计出现误差。该文提出了一种基于单快拍迭代超分辨处理的多通道雷达前视成像算法,通过对单个空域快拍的迭代谱估计可获得目标的准确位置和幅度信息,再通过多个脉冲的非相干累积得到前视方位高分辨成像。仿真和实测数据处理结果表明,所提算法具有分辨多目标的能力,相较于传统前视成像算法显著提高了前视图像的方位分辨率,同时保证了点目标的精确重构和面目标的轮廓重构。The direction of arrival estimation algorithm can overcome the Rayleigh limit,effectively separate multiple targets within the main lobe,and improve the azimuth resolution when applied to forward-looking imaging in airborne multi-channel radar.However,the limited antenna beam coverage and rapid scanning result in a scarcity of data samples available for covariance matrix estimation,leading to direction and amplitude estimation errors.Herein,we propose a forward-looking imaging algorithm based on single-snapshot iterative super-resolution estimation.The algorithm performs single-snapshot iterative spectral estimation to accurately determine the azimuth and amplitude of the target.Subsequently,a high-resolution image is achieved through non-coherent accumulation.Simulation and experimental data processing results show that the proposed algorithm can resolve multiple targets,significantly improving the azimuth resolution of the forward-looking image compared with traditional forward-looking imaging algorithms.Moreover,it ensures the accurate reconstruction of point targets and contour reconstruction of area targets.

关 键 词：波达角估计 前视成像 单快拍 迭代超分辨 迭代最小均方误差 

分 类 号：TN957.5[电子电信—信号与信息处理] TN959.4[电子电信—信息与通信工程]