Monitoring thermal dilations with millimetre sensitivity via multi-dimensional SAR imaging

The new generation of high resolution Synthetic Aperture Radar (SAR) sensors provides a new “light” in the imaging and monitoring of built areas and structures: Ground structures can be now monitored to an unprecedented accuracy. Particularly the use of higher frequency enhances the sensitivity of the system even to minute changes, such as thermal dilations. By extending multitemporal differential interferometry SAR processing chains, in our case based on the multidimensional imaging approach, an additional parameter related to temperature at acquisition instants can be accurately estimated. In this work we investigate the application of the multi-dimensional SAR imaging technique to very high resolution TerraSAR-X data acquired over the city of Potenza (south Italy), with a particular attention to Musmeci bridge. Results demonstrate the potential of this technology to accurately monitor even minute deformations of the bridge, such as those caused by thermal dilations.