In the presence of abrupt change events, multitemporal synthetic aperture radar (SAR) data represent a precious supporting tool for quantifying changes, in particular in urban areas. A large amount of SAR data also exists at very high resolution (VHR). Over urban areas, the introduction of the VHR imagery moves the analysis down to the single building scale. However, VHR imagery is also characterized by a large heterogeneity and a more complex representation of the building. In this work, we propose a geometrical model for describing partially destroyed buildings and derive the corresponding multitemporal backscattering signature by applying the ray-tracing method. The model is integrated into an unsupervised automatic approach for the detection of both fully and partially destroyed buildings. The strategy considers a hierarchical structure of the changes. Experimental results conducted on two multitemporal VHR SAR datasets show a large robustness of the approach and good accuracy in the detection of the classes for damaged buildings with different severity levels.

中文翻译：

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多时相 VHR SAR 图像中完全和部分毁坏建筑物的无监督检测方法

在发生突变事件时，多时相合成孔径雷达 (SAR) 数据是量化变化的宝贵支持工具，尤其是在城市地区。大量 SAR 数据也以超高分辨率 (VHR) 存在。在城市地区，VHR 图像的引入将分析向下移动到单个建筑规模。然而，VHR 图像的另一个特点是具有较大的异质性和更复杂的建筑物表示。在这项工作中，我们提出了一个几何模型来描述部分毁坏的建筑物，并通过应用光线追踪方法推导出相应的多时态反向散射特征。该模型被集成到一种无监督的自动方法中，用于检测完全和部分毁坏的建筑物。该策略考虑了更改的层次结构。在两个多时相 VHR SAR 数据集上进行的实验结果表明，该方法在检测具有不同严重程度的受损建筑物的类别方面具有很大的鲁棒性和良好的准确性。