Permanent Scatterers for SAR sensor Calibration

Abstract:
We propose a novel technique to perform long term system calibration exploiting the amplitude time series of Permanent Scatterers (PS) in a dataset of several SAR images. The goal is the estimation of a normalization instrument gain trend/drift along time with high accuracy and then reduce the use of transponders. The use of PS does not provide by itself the absolute calibration, but is suited to be integrated with external information (corner reflectors, Transponders, etc). Such calibrators don’t need to be maintained, as the PS technique can provide the continuous coverage in time. The technique has been tested on ERS-2 datasets.