D-InSAR technique based on time series of SAR images has been very popular to monitor ground slow deformation in recent years, such as Permanent Scatterers (PS) method, small baseline subsets (SBAS) method, and coherent targets (CT) method. By taking advantage of PS method and CT method, in this paper, small baseline and Permanent Scatterers D-InSAR technique are used to investigate the ground deformation of Tongzhou district in Beijing City, from January 4, 2009 to August 14, 2011 by using 21 COSMO-SkyMed single complex images. The experiment ...