Possibilities and limits of urban change detection using polarimetric SAR data

This paper introduces the topic of urban change detection by means of fully and dual polarized multitemporal spaceborne SAR data. The aim is to be able to detect not only urban extent expansion/shrinking phenomena, but changes that may affect both the two- and the three-dimensional landscape. For fully polarized SAR, we further validate and refine a recently introduced approach based on superpixel segmentation followed by the computation of selected polarimetric parameters and the analysis of the difference among feature vectors using specialized distance metrics. As for dual polarized SAR data, a combination of interferometric and polarimetric features within the same framework is proved to perform decently, but no real advantage if using polarimetry is obtained. Test cases using UAVSAR and Sentinel-1 data are presented in support of the proposed techniques.