引入旋转二面角模型的极化SAR七分量分解方法  

Seven-component decomposition method with extend rotated dihedral model for polarimetric SAR

作　　者：宋晴 付海强[1] 朱建军[1] 张舒蓉 SONG Qing;FU Haiqiang;ZHU Jianjun;ZHANG Shurong(School of Geosciences and Info-Physics,Central South University,Changsha 410083,China)

机构地区：[1]中南大学地球科学与信息物理学院,长沙410083

出　　处：《测绘工程》2024年第4期16-22,28,共8页Engineering of Surveying and Mapping

基　　金：国家自然科学基金重点国际(地区)合作研究项目(41820104005);国家自然科学基金资助项目(42030112)。

摘　　要：在排列方向与传感器飞行方向不平行的建筑物区域(即非平行建筑),常规的二面角散射模型基于反射对称的条件,无法准确描述非反射对称成分的电磁波散射过程,相干矩阵中的T 33项被归因于体散射成分,造成城区建筑物体散射高估的现象。现有极化分解模型大多采用扩展体散射模型的方式来构建倾斜城区非反射对称分量,此类方法能降低建筑物区域体散射,但同时也会导致森林区体散射的低估。从对倾斜城区建筑物建模的角度出发,在不改变已有体散射模型的基础上,提出一种定向角补偿的各向同性二面角模型,该模型能解释极化相干矩阵T 23项的实部,且能描述城区具有不同方位角的建筑物的散射过程。在此基础上,将此二面角散射模型与Singh提出的六分量分解模型相结合,扩展一种新的七分量分解模型。文中选取L波段ALOS-2/PALSAR-2全极化数据,分别在旧金山实验区、长沙实验区进行引入旋转二面角模型的七分量分解实验。实验结果表明,在倾斜的建筑物区域,文中提出的方法能有效改善体散射高估的情况,并能有效地区分倾斜建筑物和森林,对识别和提取城区建筑物具有重要的意义。In the area of buildings whose orientation is not parallel to the flight direction of sensors(referred to as non-parallel buildings),the conventional dihedral Angle scattering model is based on the condition of reflection symmetry,which cannot accurately describe the electromagnetic wave scattering process of non-reflection symmetry component.The T 33 term in the coherence matrix is attributed to the volume scattering component,resulting in overestimation of the scattering of urban buildings.Most of the existing polarimetric decomposition models use the extended volume scattering model to construct the non-reflective symmetric components in inclined urban areas.Such methods can reduce the volume scattering in building areas,but also lead to underestimation of the volume scattering in forest areas.In this paper,an isotropic dihedral Angle model with directional Angle compensation is proposed without changing the existing volume scattering model.This model can explain the real part of the polarization coherence matrix T 23 and describe the scattering process of buildings with different azimuths in urban areas.On this basis,the dihedral Angle scattering model is combined with the six-component decomposition model proposed by Singh,and a new seven-component decomposition model is extended.In this paper,L-band ALOS-2/PALSAR-2 full polarization data are selected to carry out seven-component decomposition experiments with rotating dihedral Angle model in San Francisco experimental area and Changsha experimental area respectively.The experimental results show that the method proposed in this paper can effectively improve the overestimation of volume scattering and distinguish the inclined buildings from the forest,which is of great significance for the identification and extraction of urban buildings.On this basis,the dihedral scattering model is combined with the six-component decomposition model proposed by Singh,and a new seven-component decomposition model is extended.In this paper,L-band ALOS-2/PALSAR-2 full polariz

关 键 词：非平行建筑物 非反射对称 极化分解 定向角补偿 各向同性 二面角模型 七分量分解 

分 类 号：TP751[自动化与计算机技术—检测技术与自动化装置]