Atmospheric Phase Delay Correction of D-Insar Based on Sentinel-1a

Abstract

ABSTRACT:In this paper, we used the Generic Atmospheric Correction Online Service for InSAR (GACOS) tropospheric delay maps to correct the atmospheric phase delay of the differential interferometric synthetic aperture radar (D-InSAR) monitoring, and we improved the accuracy of subsidence monitoring using D-InSAR technology. Atmospheric phase delay, as one of the most important errors that limit the monitoring accuracy of InSAR, would lead to the masking of true phase in subsidence monitoring. For the problem, this paper used the Sentinel-1A images and the tropospheric delay maps got from GACOS to monitor the subsidence of the Yellow River Delta in Shandong Province. The conventional D-InSAR processing was performed using the GAMMA software. The MATLAB codes were used to correct the atmospheric delay of the D-InSAR results. The results before and after the atmospheric phase delay correction were verified and analyzed in the main subsidence area. The experimental results show that atmospheric phase influences the deformation results to a certain extent. After the correction, the measurement error of vertical deformation is reduced by about 18 mm, which proves that the removal of atmospheric effects can improve the accuracy of the D-InSAR monitoring.

The Use of Interferometric Synthetic Aperture Radar for Isolating the Contribution of Major Shocks: The Case of the March 2021 Thessaly, Greece, Seismic Sequence

“…It is possible to overcome (or at least limit) the atmospheric delay, and as such the multi-temporal InSAR approach (that is not the object of this paper) has been developed over the last two decades and is nowadays widely used, especially to study the post-seismic phase and monitor a large variety of phenomena affecting the Earth's surface. With the aim of mitigating the undesired contribution of the atmosphere in the coseismic phase, it is possible to introduce tropospheric delay maps from the date in question that can be provided by many external sources (i.e., GACOS delay maps [31]) into the SAR data processing.…”