基于数字波束锐化的高速前视合成孔径雷达成像算法  

Imaging algorithm of high velocity forward-looking SAR based on digital beam sharpening

作　　者：庞礴[1] 王雪松[1] 代大海[1] 邢世其[1] 李永祯[1] 

机构地区：[1]国防科学技术大学电子信息系统复杂电磁环境效应国家重点实验室,湖南长沙410073

出　　处：《电波科学学报》2014年第1期92-98,共7页Chinese Journal of Radio Science

基　　金：国家自然科学基金资助项目(No.61302143);863资助项目(No.2013AA122202)

摘　　要：针对目前前视合成孔径雷达(Synthetic Aperture Radar,SAR)成像算法都基于平台前向运动速度较低,无法应用于高速运动平台的问题,以单发多收的机载前视SAR系统为研究对象,分析了高速前视SAR的空间几何模型和回波信号模型,提出了一种适合于高速前视SAR的多普勒波束锐化(Digital Beam Sharpening,DBS)成像算法.同时,为了解决高速运动带来的成像模糊问题,提出了相应的距离徙动校正方案,显著提高了DBS算法的成像质量.最后,模拟了点目标阵列的前视SAR回波数据,并利用所提出的算法进行了成像.成像结果验证了算法的有效性.Aiming at the problem that existing imaging algorithms of forward-looking synthetic aperture radar（SAR）which is all based on the situation that the platform is moving in low velocity,and thus can not be applied to platform of high velocity,taking airborne forward-looking SAR system using single transmitting and multiple receiving antennas as the research object,the model of spatial geometry and echo signal of high velocity forward-looking SAR is analyzed and the digital beam sharpening（DBS）imaging algorithm which is suitable for high velocity forward-looking SAR is proposed.Meanwhile,in order to solve the imaging problem brought by high velocity,corresponding range migration correction scheme is proposed,and imaging quality of DBS algorithm is remarkably improved after correction.Finally,the raw echo data of an array of point targets is simulated,and the focused images are obtained using the proposed algorithm.Imaging results demonstrate the validity of the algorithm.

关 键 词：合成孔径雷达 前视 成像 高速 多普勒波束锐化 

分 类 号：TN95[电子电信—信号与信息处理]