提出一种极化干涉SAR数据滤波方法.通过结合最优干涉相干系数和Freeman-Durden分解的非监督分类方法,利用干涉信息对极化信息不敏感的体散射区域进行进一步的划分;再选择与中心像素同类且干涉相位相近的像素参与滤波,达到在滤波的同时更好地保护数据极化信息和干涉信息的目的.利用ESAR数据进行实验,证明2种改进算法在抑制相干斑的同时,能有效保持目标散射特性、数据极化信息和干涉信息.
A speckle filter for polarimetric synthetic aperture radar interferometry data is proposed. By using the unsupervised classification method which combines optimal polarimetric interference coherence with Freeman-Durden decomposition and by selecting the pixels belonging to the same classification as the central pixel and having simiar interferometric phase to the center pixel, the filter can suppress speckle noise well while protect data polarization information and interference information. ESAR data are used in experiment.
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