Towards Deformation Monitoring of Single Buildings - Persistent Scatterer Interferometry using TerraSAR-X Very High Resolution Spotlight Data

Abstract:
Persistent Scatterer Interferometry (PSI) has matured to an established method for monitoring of surface deformation from space. With medium resolution SAR data from ERS/ENVISAT subsidence rate accuracies of up to 1 mm/year have been demonstrated. Since the beginning of 2008, TerraSAR-X delivers SAR images at meter resolution, using high resolution spotlight mode at 300MHz bandwidth, which establishes new potentials of PSI due to the enormous amount of Persistent Scatterers (PSs) now available. The number of PSs increased by a factor of approximately 100-200 compared to ERS/ENVISAT data, whereas especially facades and roofs of buildings show a high density of PSs. Small structures now act as stable scatterers and PSs from different floors can be separated due to this very high resolution of up to 1.1 m in azimuth and 0.6 m in range direction. In this paper the inner city of Berlin will be investigated with respect to deformation monitoring of single buildings. Especially the availability of stacks acquired from different viewing geometries facilitates the separation of vertical as well as horizontal movement of the PSs within the constructions.