Building Density Change Monitoring Using Dual-Polarimetric Sentinel-1 SAR Data

Building density parameter is one of the main indicators of urban monitoring. The accurate and rapid monitoring of building density changes can provide an important basis for urbanization management. It is of great significance to extract building density using dual-polarimetric Sentinel-1 SAR data which provides a short revisit period and a wide coverage. Therefore, this paper proposes a monitoring method of urban building density change based on dual-polarimetric Sentinel-1 data, integrating dual polarization information and texture features. Firstly, a dual polarimetric Sentinel-1 building index is constructed by analyzing the descriptive effects of SAR images on buildings. Then, the building index is used to monitor the change of building density. The experimental results show the effectiveness and practicality of this method by using the dual-polarimetric Sentinel-1 SAR data of Wuhan from 2018 to 2020. The experiments on the Huoshenshan and Leishenshan hospital before and after the construction during the COVID-19 pandemic can also prove the short-term monitoring ability of Sentinel-1 satellite in the rapid construction and expansion of urban areas.