Subsidence monitoring using ascending and descending SAR data based on coherent target DInSAR

Persistent Scatterer Interferometry (PSI) has been wildly applied to subsidence monitoring over a long temporal scale, which overcomes the problems caused by temporal and geometric decorrelations and the atmospheric dishomogeneities in conventional DInSAR by only considering the coherent pixels on temporal scale. Recently, only ascending or descending SAR data are used in most of PSI works, which is often subject to absence of SAR data in some years, continuous subsidence monitoring is not available. In this study, to realize the continuously deformation monitoring, both ascending and descending ENVISAT ASAR acquisitions of Suzhou city from 2003-2007 are taken into account. To process the two data sets at the same time, a modified linear deformation model is introduced into Coherent Target DInSAR (CT-DInSAR) technique. The result obtained in this paper suggested that by using ascending and descending orbit SAR data, more SAR acquisitions can be used in SBAS technique and continuous deformation monitoring can be operational.