Angular extent effect of micromotion target in SAR image by polar format algorithm  

作　　者：Bin Deng Yuliang Qin Hongqiang Wang Yanpeng Li 

机构地区：[1]School of Electronic Science and Engineering, National University of Defense Technology

出　　处：《Journal of Systems Engineering and Electronics》2014年第3期428-433,共6页系统工程与电子技术（英文版）

基　　金：supported by the National Natural Science Foundationof China(61302148;61101182)

摘　　要：Target micromotion not only plays an important role in target recognition but also leads to esoteric characteristics in synthetic aperture radar （SAR） imaging. This paper finds out an interesting phenomenon, i.e. the angular extent effect, in micro-motion target images formulated by the polar format algorithm. A micromotion target takes on multiple pairs of paired echoes （PEs） around the true point, and each PE extends for an angle which is exactly equal to the angular extent of the synthetic aperture, regardless of the micromotion frequency. The effect is derived and interpreted by using the characteristics of Bessel functions. Then it is demonstrated by simulation experiments of a target with different micromotion frequencies. The revelation and interpretation of the effect is highly beneficial to micromotion-target SAR image understanding as wel as target recognition.Target micromotion not only plays an important role in target recognition but also leads to esoteric characteristics in synthetic aperture radar （SAR） imaging. This paper finds out an interesting phenomenon, i.e. the angular extent effect, in micro-motion target images formulated by the polar format algorithm. A micromotion target takes on multiple pairs of paired echoes （PEs） around the true point, and each PE extends for an angle which is exactly equal to the angular extent of the synthetic aperture, regardless of the micromotion frequency. The effect is derived and interpreted by using the characteristics of Bessel functions. Then it is demonstrated by simulation experiments of a target with different micromotion frequencies. The revelation and interpretation of the effect is highly beneficial to micromotion-target SAR image understanding as wel as target recognition.

关 键 词：synthetic aperture radar （SAR） MICROMOTION MICRO-DOPPLER polar format algorithm （PFA） angular extent effect. 

分 类 号：TN957.52[电子电信—信号与信息处理]