针对回波数据异常时的雷达前视超分辨快速成像方法  

Fast Radar Forward-looking Super-resolution Imaging for Abnormal Echo Data

作　　者：李维新 李明[2] 陈洪猛[3] 左磊[2] 王东 杨磊 辛东金 LI Weixin;LI Ming;CHEN Hongmeng;ZUO Lei;WANG Dong;YANG Lei;XIN Dongjin(School of Information Science and Engineering,University of Jinan,Jinan 250022,China;National Laboratory of Radar Signal Processing,Xidian University,Xi’an 710071,China;Beijing Institute of Radio Measurement,Beijing 100854,China)

机构地区：[1]济南大学信息科学与工程学院,济南250022 [2]西安电子科技大学雷达信号处理国家重点实验室,西安710071 [3]北京无线电测量研究所,北京100854

出　　处：《雷达学报（中英文）》2024年第3期667-681,共15页Journal of Radars

基　　金：山东省科技型中小企业创新能力提升工程(2023TSGC0332,2023TSGC0141)。

摘　　要：机载扫描雷达前视成像可广泛应用于态势感知、自主导航和地形跟随。在雷达扫描过程中受到不经意的电磁脉冲干扰或设备性能异常等影响时,雷达回波数据出现异常值。已有的超分辨方法可以抑制回波中的异常值、提高角度分辨率,但没有考虑计算实时性问题。针对上述问题,该文提出了一种机载雷达超分辨方法实现回波数据异常时的快速前视成像。为了更好地拟合回波噪声,引入对异常值更加鲁棒的学生t分布,并采用期望最大化方法对成像参数进行估计。受截断奇异值分解方法的启发,将截断的酉矩阵引入目标散射系数的估计公式中。通过矩阵变换降低了求逆矩阵的尺寸,从而降低了参数估计的计算复杂度。仿真结果表明该文提出加速方法可以用更短的时间提高前视成像的角度分辨率,抑制回波数据中的异常值。Forward-looking imaging of airborne scanning radar is widely used in situation awareness,autonomous navigation and terrain following.When the radar is influenced by unintentional temporally sporadic electromagnetic interference or abnormal equipment performance,the echo signal contains outliers.Existing super-resolution methods can suppress outliers and improve azimuth resolution,but the real-time computing problem is not considered.In this study,we propose an airborne scanning radar super-resolution method to achieve fast forward-looking imaging when echo data are abnormal.First,we propose using the Student-t distribution to model noise.Then,the expectation-maximization method is used to estimate the parameters.Inspired by the truncated singular value decomposition method,we introduce the truncated unitary matrix into the estimation formula of the target scattering coefficient.Finally,the size of inverse matrix is reduced and the computational complexity of parameter estimation is reduced through matrix transformation.The simulation results show that the proposed method can improve the azimuth resolution of forward-looking imaging in a shorter time,and suppress outliers in echo data.

关 键 词：前视成像 超分辨 数据异常 矩阵变换 

分 类 号：TN957[电子电信—信号与信息处理]