Distributed Satellite InSAR Fine Coregistration Algorithm Using Coarse DEM

This paper deals with the problem that the ideal interferometric phases are unavailable in the maximum coherent correlation method for distributed satellite interferometric synthetic aperture radar (InSAR) image fine coregistration. A DEM-assisted approach is proposed to estimate the ideal interferometric phases. The proposed method firstly simulates the interferometric phase using the orbit information and a coarse DEM after coarse coregistration. In fine coregistration processing the shifts of each block are estimated by the maximum coherent correlation method after removing the simulated interferogram. Meanwhile, the geolocation and fringe simulation method with coarse DEM are proposed with multi-static SAR focusing geometry which can be used in various SAR acquisition modes. Finally, the validity of the method is demonstrated by ERS-1/2 real data.