Extended Integrative Combined Orbit Determination Models Based on Prior Trajectory Information and Optimal Weighting Algorithm

摘要

For multi-LEO combined orbit determination (COD) satellite-network based on space-based tracking telemetry and command (STTC) satellites, kinematic orbit information can be obtained only using the method of precise point positioning (PPP) based on observation models, but the results are not very precise because of observation data precision and GDOP of constellation. If kinematic orbit information of low earth orbit (LEO) can be taken full advantage of participating in dynamic precise orbit determination (POD) and making them achieve best matching, integrative COD models based on kinematic and dynamic information can be constructed to realize dynamic smoothness of kinematic information. Firstly, single LEO difference positioning model and the corresponding algorithm was designed, and integrative COD models were constituted based on kinematic and dynamic trajectory information. Then extended integra-tive COD models based on prior trajectory information considering nonlinear semi-parametric modeling of observation models errors and sparse parameters modeling of dynamic models were established, and the optimal weighting algorithm of multi-structural nonlinear COD models was designed. Theoretical analysis and simulation computation results show that COD weighting method based on prior trajectory information can realize LEOs dynamic information optimal matching with kinematic prior information, and can restrain nonlinear influence factor including measure models and ephemeris errors to the effects of POD precision by considering models errors modeling and dynamic models sparse parameters denotation.