InSAR tropospheric error correction by correlation analysis of sub-aperture interferograms
In order to solve the problem that the tropospheric delay error is difficult to remove in the repeat-pass InSAR measurement,this paper takes InSAR terrain mapping as an example and proposes a tropospheric delay correction method by correlation analysis of sub-aperture interferograms,combining sub-aperture division and wavelet multi-resolution correlation analysis techniques.Using single baseline ALOS-1 PALSAR data under different terrain conditions,experiments were conducted to extract Digital Elevation Models(DEM),and the accuracy was validated using ICESat-2 ground elevation data.The results demonstrate that:the new method improves the accuracy of the InSAR DEM by 30%,significantly enhancing the height measurement accuracy of InSAR technology;the new method detects and eliminates tropospheric delay errors using only single baseline InSAR data without relying on any external water vapor data,providing a feasible technical solution to improve the measurement accuracy of future repeat-pass SAR systems.