An Improved Independent Parameter Decomposition Method for Gaofen-3 Surveying and Mapping Calibration

The Gaofen-3 (GF-3) satellite can provide digital elevation model (DEM) data from its interferogram outputs. However, the accuracy of these cannot be ensured without applying a surveying and mapping (SAM) calibration process, thus necessitating geometric interferometric technologies. In this paper, we propose an independent parameter decomposition (IPD) method to conduct SAM on GF-3 generate high-accuracy DEMs. We resolved parameters improve location height accuracy. First, established model, analyzed Range–Doppler (RD) initial imaging time error as well slant range error. Then, three-dimensional reconstruction (TDR) analyze sources. Finally, phase baseline vector were precisely estimated ensure vertical results by establishing model. then used derived same orbit in north–south distribution experiment. show that plane positioning was 5.09 m following calibration, 4.18 average absolute DEM product better than 3.09 when using SAR data, confirming correctness effectiveness proposed IPD method. These technical basis for interferograms at 1:50,000 scale China.