Integration of TerraSAR-X and PALSAR PSI for detecting ground deformation

In connection with the detection of various spatial- and temporal-scale ground settlements, an integrated persistent scatterer interferometry (PSI) approach is discussed using multi-source, multi-temporal, and multi-resolution synthetic aperture radar (SAR) data. Based on the comprehensive analysis of characteristics of available radar sensors, two remote-sensing SAR data sets were selected: 1 m resolution X-band TerraSAR-X and 10 m resolution L-band Advanced Land Observing Satellite (ALOS) phased array L-band SAR. ‘Tianjin Binhai New Area’ has become one of the most important economic centres in China, and one of its fast-developing urban areas, Tanggu, was selected as the study area. PSI processing was conducted on both data sets. Substantial validation was performed for PSI results from both data sources using levelling measurement. The overall good agreement confirmed the ground deformation maps derived from both data sets. Integration of PSI results appears to be a potentially significant contribution to solving the problems related to common spatial and temporal gaps when using single-type data sets. Application of both data sets revealed the capability of integrated PSIs to measure ground deformation with strong temporal and spatial variation, thereby improving the interpretation of ground deformation characteristics which increases the confidence of hazard assessment and provides some insight into complex underlying mechanisms.