Monitoring ground displacements at centimeter level exploiting TerraSAR-X range measurements

Abstract

The goal of this work is to exploit the slant-range measurements reaching centimetre accuracies using only the amplitude information of SAR data acquired by TerraSAR-X satellite sensor. The leading idea is to evaluate the positioning accuracy of well identifiable and stable natural and man-made Persistent Scatterers (PS's) along the SAR line of sight. New Earth observation SAR (Synthetic Aperture Radar) satellite sensors, as COSMO-SkyMed, TerraSAR-X and PAZ, acquire imagery on any point of the Earth with high resolutions, in terms of phase and amplitude value. Thanks to this higher amplitude resolution (up to 0.20 m pixel resolution in the Staring SpotLight mode for TerraSAR-X and PAZ) and to the use of on board dual frequency GPS receivers, which allows to determine the satellite orbit with an accuracy at few centimetres level, the SAR images offer the capability to achieve, in a global reference frame, positioning accuracies in the meter range and even better.