Improving PSI processing of mining induced large deformations with external models

The surface deformation caused by coal mining may cause various geological disasters. Many scholars use for mine monitoring Persistent Scatterer Interferometry (PSI) combined with external models to compensate the phase wrapping when strong gradient deformations are present. In this paper, a method to increase the accuracy of the external model adjustment is presented. The evaluation is carried out by comparing the modeless conventional PSI approach and the proposed method. The results show that the proposed method could better retrieve non-linear deformation. The comparison of PSI results with in-situ leveling data shows that the error on the deformation time-series is reduced by 35.3%.