I Introduction
Differential interferometric synthetic aperture radar (DInSAR) is a technique that uses two or three SAR images including common area for interference to estimate the ground deformation during a particular time. It has good precision and can even detect millimeter level movement, so it has been applied in different areas such as detecting mine subsidence, earthquake and volcano activities, glacier movement, and etc. But if the images have low correlation for the surface of ground changed between the periods images acquisition, the registration and interferometric processing are difficult and will elicit poor conclusion. Furthermore, the atmospheric effect will bring error to the interferometric result, in particular of small and slow deformation compared with atmospheric error.