基于线性正则变换的复杂运动目标的3-D InISAR成像  

3-D InISAR imaging for targets with complex motion based on linear canonical transform

作　　者：辛红彩 李炳照 Hongcai XIN;Bingzhao LI(Department of Cryptology Science and Technology,Beijing Electronic Science and Technology Institute,Beijing 100070,China;School of Mathematics and Statistics,Beijing Institute of Technology,Beijing 100081,China;Beijing Key Laboratory on Mathematical Characterization Analysis and Application of Complex Information,Beijing Institute of Technology,Beijing 100081,China)

机构地区：[1]北京电子科技学院密码科学与技术系,北京100070 [2]北京理工大学数学与统计学院,北京100081 [3]北京理工大学复杂信息数学表征分析与应用北京市重点实验室,北京100081

出　　处：《中国科学：信息科学》2023年第10期1994-2015,共22页Scientia Sinica(Informationis)

基　　金：国家自然科学基金(批准号:62171041);中央高校基本科研业务费专项资金(批准号:328202201)资助项目。

摘　　要：二维的逆合成孔径雷达(two-dimensional inverse synthetic aperture radar,2-D ISAR)成像是目标三维(three-dimensional,3-D)几何结构在成像平面的投影,逐渐难以满足现代工程中目标识别与分类的需求,特别是复杂运动目标.近年来,干涉ISAR(interferometric ISAR,InISAR)成像技术能够高分辨地重构3-D目标的几何结构而颇受关注.本文提出一种基于线性正则变换(linear canonical transform,LCT)的复杂运动目标的3-D InISAR成像算法.首先,结合目标复杂运动分析,给出了目标所产生的原始回波信号.经过运动补偿和图像对准后,将方位向回波建模为线性调频(linear frequency modulation,LFM)信号.其次,根据LFM信号的时频特性,本文提出了基于LCT的2-D ISAR成像算法.该算法不仅能够获取聚焦的多通道2-D ISAR图像,而且很好地保留了相位信息.最后,利用干涉技术,提出了新的3-D InISAR成像算法,实现了目标的高分辨3-D几何结构重建.此外,文中讨论并分析了所提算法的时频聚集性、计算量和基线长度影响.不同的仿真实验和结果证明了所提算法的优越性能.The two-dimensional inverse synthetic aperture radar(2-D ISAR)image is a 2-D projection of the three-dimensional(3-D)shape of the target,and it is difficult to meet the demand of recognition and classification,especially of targets with complex motion.Recently,interferometric ISAR(InISAR)has been receiving increasing attention since it can reconstruct the 3-D shape of the target with high resolution.This paper proposes a novel 3-D InISAR imaging algorithm based on linear canonical transform(LCT)for targets with complex motion.In this method,the initial echo signal model is generated after analyzing the complex motion of the target.After motion compensation and image coregistration,the azimuth echo is modeled as linear frequency modulation(LFM)signal.Given the time-frequency characteristics of LFM signal,then a new 2-D ISAR imaging algorithm based on LCT is developed to obtain well-focused and multi-channel 2-D ISAR images as well as preserve the phase information of images.Finally,employing the interferometric technique,a novel 3-D InISAR imaging method is proposed and the high-resolution 3-D shape of the target can be reconstructed.In addition,the time-frequency concentration,moderate computation cost and effect of baseline are discussed,and different simulation experiments and results verify the superior performance of the proposed method.

关 键 词：复杂运动目标 InISAR 线性正则变换 成像算法 三维坐标重构 

分 类 号：TN957.52[电子电信—信号与信息处理]