Reduction of Atmospheric Effects on InSAR Interferograms Based on CORS
1 School of Geodesy and Geomatics,Wuhan University, 129 Luoyu Road , Wuhan 430079, China
2 Surveying and Mapping Institute of Beijing, 15 Yangfangdian Road, Beijing 100038, China
Abstract This paper is concerned with the problem of lack of CORS stations when using GPS data to correct the DInSAR atmospheric delay error. The paper puts forward a generalized curve surface fitting interpolation model and compares the precision of modeling regional tropospheric delay by using the inverse distance weighted interpolation model (IDW) and the curve surface fitting interpolation model (CSF), based on GPS observation data and SAR imaging data from Beijing. Further, it tries to conduct an atmospheric delay correction for SAR differential interferograms. The results show that compared with IDW, CSF can better reflect the delay features of the regional single difference tropospheric delay. In addition, the interpolation precisions of the two experiments are 7.1 mm and 3.5 mm respectively. By using CORS observation data and the CSF model, the atmospheric delay errors in DInSAR are effectively reduced and the precision of DInSAR measurement results is improved.
