Joint Spatio-Temporal Correction for Both Turbulent and Stratified Tropospheric Delays in TS-InSAR

Synthetic aperture radar interferometry (InSAR) has been applied in ground deformation monitoring. However, the interferograms are susceptible to tropospheric delay artifacts, including both turbulent delays and stratified ones, especially in mountainous regions, due to temporal and spatial variation of temperature, humidity and pressure in the troposphere. Most atmospheric correction methods only address one of the delays and lack comprehensive consideration, thus it is hard to suppress the atmospheric artifacts completely. In this paper, we proposed a joint spatio-temporal correction (JSTC) method for both turbulent and stratified delays, which applies a dual-scale temporal low-pass filter to separate turbulent delays from other low-frequency components in temporal domain, then adopts the quadtree segmentation to correct stratified delays caused by spatial heterogeneity. The proposed method was first validated by simulated data, and then tested by real data in the mountainous region. The results demonstrated that our method can significantly reduce the impact of atmospheric artifacts on the interferograms.