机载UWB SAR图像中残余相位误差的补偿算法  

A Compensating Algorithm for Residual Phase Error in Airborne UWB SAR Images

作　　者：王亮[1] 杨磊 安道祥[1] 黄晓涛[1] 

机构地区：[1]国防科学技术大学电子科学与工程学院,湖南长沙410073 [2]空军军械通用装备军事代表局,北京100071

出　　处：《雷达科学与技术》2007年第4期269-277,共9页Radar Science and Technology

基　　金：国防预研项目(No.408010202)

摘　　要：已经初步聚焦的超宽带合成孔径雷达图像需要补偿残余的相位误差,才能进一步提高图像的聚焦性能。首先建立了适合机载UWB SAR成像几何的相位误差模型,并分析了其特点;然后针对模型特点,对条带式相位梯度自聚焦算法作出改进,同时提出一种基于空不变因子估计的加权相位梯度自聚焦算法。最后,由一段实测UWB SAR图像补偿结果检验了算法的可行性。Ultra wideband synthetic aperture radar（UWB SAR） images that have been focused elementarily need further compensation for residual phase errors to improve focusing performance. In this paper, a residual phase error model fitting for the imaging geometry of the airborne UWB SAR is founded, and the model characteristics are analyzed. And then, the strip phase gradient autofocus（PGA） algorithm is ameliorated. An improved PWE-PGA（phase weight estimation--PGA） algorithm based on the range-independency factors estimating is proposed. Finally, the feasibility of the new algorithm is verified by use of real UWB SAR data.

关 键 词：信号处理 超宽带合成孔径雷达 相位梯度自聚焦 残余相位误差 

分 类 号：TN957.51[电子电信—信号与信息处理] TN958[电子电信—信息与通信工程]