基于FMCW的大斜视SAR成像研究  

Imaging Study of High Squint SAR Based on FMCW

作　　者：梁毅[1] 王虹现[1] 邢孟道[1] 保铮[1] 

机构地区：[1]西安电子科技大学雷达信号处理重点实验室,西安710071

出　　处：《电子与信息学报》2009年第4期776-780,共5页Journal of Electronics & Information Technology

基　　金：国家自然科学青年基金(60502044);教育部重点项目(20051009)资助课题

摘　　要：针对调频连续波SAR与脉冲式SAR工作体制的不同,从而带来不同的回波信号形式,该文对基于调频连续波的大斜视SAR回波信号进行建模,分析信号的特征,揭示平台的连续运动在距离向产生一个多普勒频移的特性,从而导致目标的径向移动。同时,针对调频连续波SAR大斜视Dechirp数据,提出了时域走动校正、频域多普勒频移校正、距离弯曲校正的改进R-D算法,仿真数据处理结果验证了该文分析的正确性和所提算法的有效性。另外,对于平台连续运动引入的多普勒频移,该文也分析了其对成像造成的影响。Based on the differences of work mechanism between Frequency Modulated Continuous Wave （FMCW） Synthetic Aperture Radar （SAR） and Pulsed Synthetic Aperture Radar, which leads to different form of received signal, this paper establishes the model of high squint FMCW SAR echo, analyzes its characteristics, and reveals the Doppler frequency shift effect induced by the continuous motion in range direction while radar transmitting and receiving signal. Meanwhile, this paper proposes a modified RD Algorithm （RDA） for high squint FMCW SAR dechirp data, which compensates for range walk in time domain, Doppler frequency shift and range curvature in frequency domain. Point target simulation verifies the analysis and validity of the algorithm. In addition, for the Doppler frequency shift induced by the platform continuous motion, this paper also analyses its effect on imaging.

关 键 词：调频连续波 大斜视SAR 改进R-D算法 

分 类 号：TN957.52[电子电信—信号与信息处理]