Combination of multiple interferograms for monitoring temporal evolution of ground deformation

SAR and differential SAR interferometry are operational tools for monitoring surface deformation and topographic profile reconstruction. However, they still have limitations due to temporal and geometric decorrelation. These disturbances strongly compromise the accuracy of the results, but reliable measurements can be obtained over a large multitemporal population of interferograms. In this paper we propose a new algorithm for monitoring temporal evolution of ground surface using several interferograms covering ground movements over a long period of time. It is based on a statistical approach with hypothesis test. The objective of multiple interferograms elevation retrieval is to deal with noisy data. An other important advantage of the multiple image processing is that all baselines (small or large) are considered. The method described in this paper can be applied in both SAR and differential SAR interferometry context. We chose to study the SAR interferometry case.