雷达成像和衍射层析的内在联系梳理  

Relationship between radar imaging and diffraction tomography

作　　者：江舸[1] 经文 成彬彬[1,2] 周剑雄[3] 张健[1,2] JIANG Ge1, JING Wen1 , CHENG Bin-Bin1,2 , ZHOU Jian-Xiong3, ZHANG Jian1,2.(1. Institute of Electronic Engineering, China Academy of Engineering Physics, Mianyang 621999, China; 2. Mierosystem and Terahertz Research Center, China Academy of Engineering Physics, Mianyang 621999, China; 3. ATR Laboratary, School of Electronics Science and Engineering, National University of Defense Technology, Changsha 410073, Chin)

机构地区：[1]中国工程物理研究院电子工程研究所 [2]中国工程物理研究院微系统与太赫兹研究中心 [3]国防科技大学电子科学与工程学院ATR实验室

出　　处：《红外与毫米波学报》2018年第4期486-492,500,共8页Journal of Infrared and Millimeter Waves

基　　金：国家自然科学基金(61601424);国家自然科学基金委员会与中国工程物理研究院联合基金(U1630101);国家重点基础研究发展计划(2015CB755406)~~

摘　　要：从方程描述、方程求解和方程解析解三个层面,对雷达成像和衍射层析的内在联系进行了系统性梳理.首先,介绍了描述成像问题的电磁散射方程,发现描述雷达的方程是二维的面积分方程,而描述衍射层析的方程是三维的体积分方程.指出成像对象不同是导致方程不同的根源,并利用等效原理建立了两种成像间的联系.其次,指出两种成像的相同点是,对非线性的电磁散射方程的线性化近似求解.最后,指出两种成像的回波信号(在空间谱域)和成像目标(在空间域)均构成一组傅里叶变换对.给出了两种成像的解析解的统一数学模型,即成像结果可表示为观测点(散射系数或散射势)卷积点扩展函数(PSF)的形式.通过PSF对两者的成像性能进行了比较.Although the similarities betw een radar imaging and diffraction tomography have been recognized,the connection betw een them is often surprising to practitioners in these fields. The main goal of this paper is to consider together tw o imaging techniques and clarify the similarities and differences that exist betw een them. First,Tw o imaging techniques are derived from Stratton-Chu formula of the inverse scattering problem,w hich allow s a clear understanding of the relationship betw een the imaging equations and the imaging targets. The targets reconstructed by radar imaging are the perfectly conducting bodies,the targets reconstructed by diffraction tomography are the dielectric bodies. Then,this derivation brings out the similarities of the solution to the unlinear imaging problem w hich are hidden by the linear approximation method,radar imaging from high frequency asymptotic approximation,diffraction tomography from w eak scattering approximation. Finally,Tw o imaging techniques are discribed as Fourier imaging,w hich is used to identify the unknow n image profile as the inverse Fourier Transform of some composite function constructed from the received data signals.

关 键 词：雷达成像 衍射层析成像 电磁逆散射 等效原理 线性化近似 傅里叶成像 点扩展函数 

分 类 号：TN957.52[电子电信—信号与信息处理] TP722.6[电子电信—信息与通信工程]