Coregistration of Interferometric Stacks of Sentinel-1A TOPS Data

Abstract

SAR images coregistration is of fundamental importance for the generation of SAR interferograms. The high azimuth coregistration requirements imposed by the novel TOPS acquisition mode converts the coregistration of stacked time series images in a demanding task due to temporal decorrelation effects. A joint coregistration approach appears to be the optimal solution for coregistering long stacks. The problem of a joint coregistration has been already addressed in the literature for the case of coherently correlating speckle signals. A similar procedure can be applied when employing the established Enhanced Spectral Diversity (ESD) technique for azimuth coregistration of TOPS images. Sentinel-1A images acquired in IW mode are used to validate this procedure, comparing its performance to the standard single- master approach.