基于多普勒分辨的连续波合成孔径雷达成像方法  

Doppler resolution based imaging method for synthetic aperture radar using continuous waveforms

作　　者：汪玲[1] 张璇[2] 韦渊斐 

机构地区：[1]南京航空航天大学电子信息工程学院雷达成像与微波光子技术教育部重点实验室,江苏南京210016 [2]上海微小卫星工程中心,上海201203

出　　处：《系统工程与电子技术》2014年第6期1057-1061,共5页Systems Engineering and Electronics

基　　金：航空科学基金(20132052035);江苏高校优势学科建设工程;南京航空航天大学科研基地创新基金(NJ20140008)资助课题

摘　　要：提出一种新的连续波(continuous waveform,CW)体制合成孔径雷达(synthetic aperture radar,SAR)成像方法。有别于脉冲波形SAR和调频连续波SAR通过发射宽带信号获得高距离分辨率,CW-SAR成像利用CW波形的高多普勒分辨率进行成像,通过将回波信号与尺度变换后的发射信号进行相关构造成像数据模型,该相关信号实际为场景散射系数在等多普勒线上的投影,基于该相关信号,采用滤波反投影图像重建算法进行场景反射率重建。该CW-SAR成像方法不仅适用于宽带和窄带CW发射波形,而且也适用于单/双基SAR和任意载机飞行轨迹。以双基情形为例,分析成像方法的性能,并进行仿真验证。A novel imaging method for synthetic aperture radar（SAR）using the continuous waveform（CW） is presented.Compared with the traditional pulse-waveform SAR and frequency-modulated CW （FM-CW） SAR,which rely on wideband signal transmission to achieve high range resolution,the CW-SAR uses the high Doppler resolution provided by the CW signals to perform the imaging.The data model for the imaging processing is formed by correlating the received signal with a scaled or frequency-shifted version of the transmitted CW signal,where the correlated signal is in fact the projection of the scene reflectivity onto the iso-Doppler curves. A filtered-backprojection image reconstruction method is presented to reconstruct the scene reflectivity using the correlated signals.The proposed imaging method for CW-SAR is applicable to wideband and narrowband CW transmission,and monostatic or bistatic SAR systems.It can also accommodate arbitrary radar platform flight trajectories.The imaging method is discussed in the framework of bistatic configuration,including the performance analysis and the demonstration using numerical simulations.

关 键 词：合成孔径雷达 成像 滤波反投影 连续波 多普勒 

分 类 号：TN957.52[电子电信—信号与信息处理]