MONITORING GROUND SUBSIDENCE WITH PERMANENT SCATTERERS INTERFEROMETRY
Hu Bo 1,2) ; and Wang Hansheng 1)
1)Key Laboratory of Dynamic Geodesy,Institute of Geodesy and Geophysics, CAS, Wuhan 4300772)Graduate School of Chinese Academy of Sciences, Beijing 100049
Abstract PSInSAR makes it possible to overcome both phase decorrelations and atmospheric delays, and shows a properous future for improving the accuracy of monitoring crustal movement. However, the key steps for the data processing are not well developed such as PS detection, network construction and model estimation. Therefore, a threethresholding algorithm i.e., a method to serially execute correlationcoefficient thresholding, amplitude dispersion index thresholding and amplitude index thresholding is proposed and implemented to improve the quality of PS detection. In addition, a method with treestructure is proposed to estimate the PS absolute terrain error and linear velocity of deformation. Finally, a case study in Shanghai experimental area is finished. The InSAR data sets from ERS1/2 and the new method proposed are utilized to successfully dectect the PS points and obtain the subsidence during the period from 1992 to 2002,that the regionally average value of the subsidence is 9.3 mm/a. The new results are basically in accordance with that from the levelling.
