Three-Dimensonal Deformation Monitoring of Urban Infrastructure by Tomographic SAR Using Multitrack TerraSAR-X Data Stacks

Abstract

Differential Synthetic Aperture Radar Tomography (D-TomoSAR), similar to its conventional counterparts, such as Differential Interferometric SAR (D-InSAR) and Persistent Scatterer Interferometry (PSI) is only capable to capture one-dimensional deformation along the satellite’s line-of-sight (LOS). In this paper we propose a method based on L1-norm minimization within local spatial cubes, to reconstruct three-dimensional displacement vectors from TomoSAR point clouds available from, at least, three different viewing geometries. The methodology is applied on two pair of cross-heading - combination of ascending and descending - TerraSAR-X (TS-X) spotlight image stacks over the city of Berlin. The linear deformation rate and the amplitude of seasonal deformation are decomposed and the results from two test sites with remarkable deformation pattern are discussed in detail. The results, to our knowledge, demonstrate the first attempt for motion decomposition using TomoSAR data from multiple viewing geometries.