Ionospheric Correction of D-InSAR Using Split-Spectrum Technique and 3D Ionosphere Model in Deformation Monitoring

Wednesday, 17 December 2014
Yanling Chen1, Linying Guo1,2, Jason Jicang Wu2, Qinming Chen1 and Shuli Song1, (1)Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai, China, (2)Tongji University, Colledge of Surveying and Geo-informatics, Shanghai, China
In Differential Interferometric Synthetic Aperture Radar (D-InSAR) atmosphere effect including troposphere and ionosphere is one of the dominant sources of error in most interferograms, which greatly reduced the accuracy of deformation monitoring. In recent years tropospheric correction especially Zwd in InSAR data processing has ever got widely investigated and got efficiently suppressed. And thus we focused our study on ionospheric correction using two different methods, which are split-spectrum technique and Nequick model, one of the three dimensional electron density models. We processed Wenchuan ALOS PALSAR images, and compared InSAR surface deformation after ionospheric modification using the two approaches mentioned above with ground GPS subsidence observations to validate the effect of split-spectrum method and NeQuick model, further discussed the performance and feasibility of external data and InSAR itself during the study of the elimination of InSAR ionospheric effect.