Orbital error estimation through multi-squint analysis

Abstract:
The main objective of synthetic aperture radar interferometry (InSAR) is to extract information about the Earth surface from the phase difference between two interferometric acquisitions. In order to properly identify and separate different contributions to the interferometric phase is necessary to perform the phase calibration of spaceborne SAR system. In this paper we evaluate the opportunity to exploit the Multi-Squint (MS) interferometric phase in order to remove InSAR fringes due to the linear orbital error, under the key assumption that the MS phase is very poorly affected by the atmospheric delay and DEM errors. Preliminary results obtained by processing TerraSAR-X stripmap data and simulated data appear to confirm the validity of this assumption, and suggest that MS processing can be operationally employed for the calibration of spaceborne InSAR data-stacks.