A Multiparameter Alternative Optimization Atmospheric Refraction Correction Method for Star Sensors With Large-Zenith-Distance Starlight

Terrestrial star sensors operating in scenarios such as aircraft, ships, and field experiments are susceptible to atmospheric refraction, especially those encountering large-zenith-distance (ZD) starlight. Therefore, this article proposes a multiparameter alternative optimization atmospheric refraction correction method. Unlike the existing studies based on the azimuthal angle invariance, the proposed method takes errors in both zenith and azimuth directions into account, which is suitable for large-ZD starlight. Considering the challenges of solving the optimization model with numerous variables, a multiparameter alternative optimization approach is employed based on Riemannian optimization and the least-squares method. The proposed method realizes atmospheric refraction correction without any instrument, thereby enhancing the attitude estimation accuracy for star sensors with large-zenith-distance starlight. Experiments indicate that compared to the current best method, the proposed method reduces the reprojection error by 20% in the region with ZDs less than 20° and by 50% in the region with ZDs greater than or equal to 20°.