InSAR Baseline Estimation for Gaofen-3 Real-Time DEM Generation

Area of Science:

• Remote Sensing
• Geodesy
• Photogrammetry

Background:

• Interferometry Synthetic Aperture Radar (InSAR) accuracy relies heavily on normal baseline.
• Gaofen-3 (GF-3) InSAR processing faces challenges with real-time orbit determination, causing baseline errors and affecting Digital Elevation Model (DEM) generation accuracy.

Purpose of the Study:

• To propose a novel baseline estimation approach for Gaofen-3 (GF-3) Interferometry Synthetic Aperture Radar (InSAR) data.
• To enhance the accuracy of real-time Digital Elevation Model (DEM) generation by addressing baseline errors.

Main Methods:

• Developed a baseline estimation method utilizing Shuttle Radar Topography Mission (SRTM) DEM.
• Implemented orbit fitting to remove non-linear error factors.
• Estimated baseline error by analyzing height differences in the slant-range plane between SRTM and GF-3 DEMs.
• Calibrated real-time orbits using the derived baseline error for improved DEM generation.

Main Results:

• The proposed method effectively estimates baseline errors, allowing for real-time orbit calibration.
• Demonstrated significant improvement in the accuracy of Gaofen-3 (GF-3) real-time DEM products.
• The approach offers spatial and precise orbital freedom, simplifying processing.

Conclusions:

• The novel baseline estimation approach significantly enhances the accuracy of GF-3 InSAR DEM generation.
• This method provides a robust solution for improving real-time DEM products by correcting orbital inaccuracies.
• The technique is effective and validated using GF-3 data over Hebei.