Correcting ionospheric and orbital errors in spacebome SAR differential interferograms

Abstract

Ionospheric phase delay and orbital errors, are major limitations for precise deformation measurement in low frequencies SAR systems. The dispersive nature of the ionosphere introduces a shift in SAR images that is translated to differential interferograms. Orbital errors are basically a result of inaccurate baseline estimation, due the estimation model or non precise orbits. In this work, we present a combined method for correcting ionospheric and orbital errors in DInSAR, using the Split-Spectrum algorithm for ionospheric phase delay estimation and compensation. The orbital noise is modeled as non linear contribution taking into account the residual topography related to the used Digital Elevation Model (DEM). The methodology is applied on real data case to test its ability to compensate for these errors.