SAR interferometry for long term deformation mapping using SBAS method: A case study in Nanjing area

Synthetic aperture radar interferometry (InSAR) is a novel remote sensing technique to measure earth surface deformation, it is capable of obtaining dense information related to the deformation of a large area quickly, economically and effectively. However, Conventional InSAR technique is easily suffered from both spatial and temporal decorrelation which limits its application, especially for long term deformation mapping. In this paper, a Small BAseline Subset (SBAS) InSAR approach, which generates interferograms between two SAR images with small spatial baseline was presented, this approach can reduce both spatial and temporal decorrelation for long term deformation using a data set of SAR images acquired subsequently; deformation maps and displacement time series of the Nanjing City, P. R. China was generated with SBAS approach. Results of 13 differential interferograms generated by 8 SAR images in Nanjing from August 1996 to April 2000, demonstrate its efficiency.