建筑物Ku波段极化SAR成像仿真及损毁评估特征分析

Imaging Simulation and Damage Assessment Feature Analysis of Ku Band Polarized SAR of Buildings

建筑物损毁评估在灾害应急监测中十分重要。近年来,随着SAR硬件多极化能力的增加,极化SAR为建筑物损毁评估提供了更多的可能性,基于极化特征的建筑物损毁评估方法逐渐成为了研究的重点。然而,由于极化SAR数据获取的限制,当前的研究主要集中在L, C, X等有限波段内。为了进一步加深对SAR图像损毁建筑物极化特征的理解并丰富其它波段下SAR图像损毁建筑物的极化特征应用,该文进行了建筑物Ku波段极化SAR仿真实验,并通过SAR图像极化分解的方法进行了损毁评估特征分析。该文首先制作了真实材料的建筑物缩比模型,利用微波特性测量与仿真成像科学实验平台对损毁前后的建筑物目标进行SAR仿真成像,获取了建筑物损毁前后的Ku波段极化SAR图像。然后,借助H=A=α分解、Yamaguchi分解、Touzi分解等极化分解方法分析了Ku波段建筑物目标损毁前后的极化散射特征,分析表明,Yamaguchi分解得到的去定向后的体散射分量、二次散射分量占比以及Touzi分解得到的αs1分量对于Ku波段建筑物损毁评估具有较好的指示意义;通过与X波段实验测量结果的对比,发现Ku波段对建筑物损毁评估更敏感,这对于未来雷达遥感应用具有重要的启发意义。

Building damage assessment is important in disaster emergency monitoring. In recent years, with the increase of multi-polarization capability of Synthetic Aperture Radar(SAR), Polarimetric Synthetic Aperture Radar(PolSAR) provides more possibilities for building damage assessment, and the polarization-characteristicbased building damage assessment method has gradually become the focus of research. However, because of the limitations of data acquisition in PolSAR, current research mainly focuses on the L, C, X, and other limited bands. To obtain an in depth understanding of the polarization characteristics of damaged buildings in SAR images and develop the application of the polarization characteristics of damaged buildings to other bands, this study conducted a simulation experiment of Ku band polarized SAR of buildings, and performed damage assessment feature analysis using the SAR image polarization decomposition method. In this study, a scale model of real materials was built and the "microwave characteristic measurement and simulation imaging scientific experiment platform" was used to conduct SAR simulation imaging of the target buildings. The Ku band polarized SAR images before and after building damage were obtained. Then, the polarization scattering characteristics of buildings before and after damage were analyzed using various common polarization decomposition methods such as H/A/αResults show that the disoriented volume scattering component and the proportion of the disoriented secondary scattering component obtained by the Yamaguchi decomposition and the α s1 component obtained by the Touzi decomposition have good indicative significance for building damage assessment in the Ku band. Compared with the X band measurement results, the Ku band is more sensitive to building damage assessment, which has important implications for future radar remote sensing applications.