干涉雷达永久散射体识别方法的对比分析

基于永久散射体的干涉测量技术可以克服卫星合成孔径雷达应用于区域地表形变探测所面临的时空失相关和大气影响.永久散射体的有效识别是干涉系统中的一个关键环节.本文对永久散射体的两种识别方法, 即相关系数阈值法和振幅离差指数阈值法进行了理论上的分析和实验上的对比.以上海市局部地区作为研究对象, 采用26幅欧洲空间局的ERS-1/2卫星C波段SAR影像为源数据, 使用两种识别方法分别进行了永久散射体的提取, 结果表明, 振幅离差指数方法具有更为稳健的抗噪能力.

Comparison and Evaluation of Identification Methods of Permanent Scatterers in Radar Interferometry

Satellite synthetic aperture radar interferometry with permanent scatterers(PS) can overcome the limitation of spatio-temporal decorrelation and atmospheric delay,and thus enhance the reliability of radar interferometry when applied in regional deformation mapping.How to identify effectively PS from SAR images is one of the crucial procedures in data reduction of the PS interferometric system.With theoretical analysis and experimental comparison,this paper evaluates two methods for PS identification,i.e.correlation coefficient thresholding and amplitude dispersion index thresholding.Using 26 C-band SAR images over Shanghai from satellites ERS-1 and ERS-2 of European Space Agency,both of the methods have been validated for PS detection.The testing results show that the amplitude dispersion index thresholding algorithm can identify PS from SAR images more effectively and reliably.