A Correction Method for Thermal Deformation Positioning Error of Geostationary Optical Payloads

摘要

Geometric positioning of a remote sensing image is one of the core technologies for the quantitative application of the geostationary satellite data. Affected by the change of the incident angle of the sunlight, the spatial thermal environment surrounding the remote sensing cameras (RSCs), especially the geostationary RSCs, fluctuates greatly and has a noticeable impact on the installation matrix based on the reference to the satellite body. Therefore, the spatial thermal environment will ultimately influence the camera's geometric positioning model and the final positioning accuracy. This paper proposes a novel correction method based on stellar observations for correcting geometric positioning error caused by spatial thermal deformation (STD) of geostationary optical payloads. The proposed method overcomes the drawbacks associated with current stabilization methods that involve shutting down the camera to reduce STD effects. Experimental results show that the positioning error corrected by the proposed method can be within +/- 1.9 pixels (2 sigma) at a 95% confidence level and better than the +/- 18 pixels before correction.