一种求解GEO星机双基地SAR二维频谱的方法  

A Method of Deriving GEO Spaceborne-airborne Bistatic SAR’s Two-dimensional Spectrum

作　　者：邸雪娜 李元吉 伍光新[1] DI Xuena;LI Yuanji;WU Guangxin(Nanjing Research Institute of Electronics Technology,Nanjing 210039,China;Key Laboratory of IntelliSense Technology,CETC,Nanjing 210039,China)

机构地区：[1]南京电子技术研究所,南京210039 [2]中国电子科技集团公司智能感知技术重点实验室,南京210039

出　　处：《现代雷达》2018年第8期31-35,共5页Modern Radar

摘　　要：求解回波信号的二维频谱是双基地合成孔径雷达（Bi-SAR）系统成像的关键问题,传统方法主要有Loffied双基公式法（LBF）和扩展Loffied双基公式法（扩展LBF）。而对于地球同步轨道星机双基地合成孔径雷达（GEO星机双基地SAR）来说,由于收发平台具有明显的异构性,采用传统方法求解回波信号二维频谱会产生较大的误差。文中针对GEO星机双基地SAR系统的结构特点,提出采用多普勒贡献比加权（DDW）的方法来求解回波信号的二维频谱,并通过仿真分析比较了LBF、扩展LBF、DDW三种方法求解回波信号二维频谱的相位误差;然后,选取GEO星机双基地SAR场景下的点目标,利用求解得到的二维频谱进行仿真成像;最后,比较了成像效果,说明采用DDW方法求解该模式下回波信号二维频谱的优越性。For bistatic synthetic aperture radar（SAR） system,the key of imaging is to derive the echo signal＇ s two-dimensional spectrum,and the main methods are Loffied＇s bistatic formula（LBF） and extended Loffied＇s bistatic formula（ELBF）.While in geosynchronous spaceborne-airborne bistatic SAR system,because of the sending and receiving platform＇s isomerism,using the traditional methods to derive the echo signal＇s two-dimensional spectrum will cause big error.In this paper,according to the structure characteristics of GEO spaceborne-airborne bistatic SAR system,the method of using the Doppler distribution weighed（DDW） to estimate the echo signal＇s two-dimensional spectrum is proposed,and the phase error of LBF、ELBF and DDW is compared by simulation.Finally the advantage of DDW to derive the two-dimensional spectrum is indicated by simulation of point targets imaging.

关 键 词：GEO星机双基地SAR 二维频谱 多普勒贡献比加权 成像 

分 类 号：TN911.7[电子电信—通信与信息系统]