基于二维指数脉冲压缩变换的SAR成像算法  

A new SAR imaging algorithm based on two-dimensional exponential pulse compression transform

作　　者：陈熙 刘禄波 季袁冬 张路[1] CHEN Xi;LIU Lu-Bo;JI Yuan-Dong;ZHANG Lu(College of Mathematics,Sichuan University,Chengdu 610064,China;College of Aerospace Science and Engineering,Sichuan University,Chengdu 610064,China)

机构地区：[1]四川大学数学学院,成都610064 [2]四川大学空天科学与工程学院,成都610064

出　　处：《四川大学学报（自然科学版）》2020年第3期425-430,共6页Journal of Sichuan University(Natural Science Edition)

基　　金：国家自然科学基金(11401405,61701329)。

摘　　要：传统的合成孔径雷达(SAR)系统一般采用经典的匹配滤波器实现距离维和方位维的二维脉冲压缩变换,其基于匹配滤波器的系统带宽导致系统分辨率是有限且固定的.当对输出信噪比和目标时延分辨率有不同要求时,具有可变指数的指数滤波器可根据具体需求在充分保证输出信噪比的情况下产生高于匹配滤波器的目标分辨率.本文基于指数滤波器将距离维和方位维上的二维指数脉冲压缩变换应用于SAR成像算法,即先后将信号通过距离维和方位维指数滤波器,以实现SAR高分辨率成像.仿真结果表明,该算法在距离维和方位维两个维度都具有比传统SAR算法处理结果更窄的主瓣宽度和更低的旁瓣高度,有效提高了距离维和方位维的分辨率.In traditional sgnthetic aperture radar(SAR) systems, the classical matched filter is extensively used to achieve the two-dimensional pulse compression of distance and azimuth dimension. The bandwidth of the system is often limited and fixed. In some practical applications, the output signal-to-noise ratio and target delay resolution have different requirements. The exponential filter with variable exponents is a better choise than matched filtering. In this paper, based on the exponential filter, a new two-dimensional exponential pulse compression transform is applied to the high-resolution SAR imaging algorithm. The simulation results show that the algorithm has a narrower main lobe width and lower side lobe height than the traditional SAR algorithm in both distance and azimuth dimension.

关 键 词：脉冲压缩变换 线性调频函数 SAR成像 分辨率 

分 类 号：O29[理学—应用数学]