电讯技术2017，Vol.57Issue(5)：510-517,8.DOI:10.3969/j.issn.1001-893x.2017.05.004
基于分数阶傅里叶变换的运动舰船聚焦算法
Moving Ship Refocusing Using Fractional Fourier Transform Algorithm
摘要
Abstract
In order to refocus the image of moving ship in synthetic aperture radar(SAR),a detection approach called contrast fractional Fourier transform(CFRFT) is presented.This algorithm is used to process SAR image by using contrast maximum and fractional Fourier transform(FRFT) method.Based on FRFT method,the signature can be represented in a rotated jointed time-frequency plane and the optimal rotated degree can be found.Taking advantage of the optimal degree,the quadratic phase error is estimated by a parametric model processing and the residual phase error can be obtained by a nonparametric model processing.The defocusing SAR image can then be compensated easily.Compared with traditional phase gradient autofocus(PGA) algorithm,the CFRFT can compensate the defocusing caused by moving ship target more effectively.The resolution and side lobe rate are also improved.The simulation and the processing results of moving ship show that this algorithm can get well focused SAR images with robustness,effectivity and high precision.关键词
合成孔径雷达/自聚焦/对比度分数阶傅里叶变换/相位误差补偿Key words
synthetic aperture radar(SAR)/autofocus/contrast fractional Fourier transform algorithm/phase error correction分类
信息技术与安全科学引用本文复制引用
孙玉鑫,丁娟娟,刘鹏..基于分数阶傅里叶变换的运动舰船聚焦算法[J].电讯技术,2017,57(5):510-517,8.基金项目
国家自然科学基金资助项目(61179022) （61179022）
