Assessment of topographical and atmospheric errors in Sentinel 1 derived DInSAR
Suresh Devaraj, Kiran Yarrakula
Abstract
Differential SAR interferometry (DInSAR) techniques are extensively utilized over decades to monitor and detect surface distortion. Interferometric SAR results obtained from Sentinel 1 data experience phase delay due to interference with the atmospheric water vapour and pressure and DEM is considered as one of the important parameter in topographic phase removal. In the present study, an attempt was made to eradicate the atmospheric errors and to assess the variation of LOS displacement with respect to different DEM. Results concluded GACOS based atmospheric correction eradicate the atmospheric error and help in improving the quality of LOS displacement. Comparison of InSAR results by utilizing SRTM, ALOS and Cartosat DEM and GACOS concluded that LOS displacement varies based on the accuracy of DEM and its resolution with the minimum error identified by utilizing CartoDEM over Kodagu region.