Multi-Squint Analysis to Separate Geometric and Atmospheric Phase Artifacts in Spaceborne InSAR

The main issue during phase calibration of spaceborne SAR system is to properly identify and separate different contributions to the interferometric phase. In this paper we suggest to exploit the Multi-Squint (MS) interferometric phase in order to remove InSAR fringes due to a linear orbital error, under the key assumption that the MS phase is very poorly affected by contributions from the atmospheric delay. Preliminary results obtained by processing TerraSAR-X stripmap data appear to confirm the validity of this assumption, and suggest that MS processing can be operationally employed for the calibration of spaceborne InSAR datastacks.