Multi-satellite Combined Orbit Determination Parameterized Fusion Model and Weighting Iterative Estimation Algorithm

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 orbits results are not very precise because that the precision of observation data and the Geometry Dilution of Precision (GDOP) of STTC constellation cannot meet the demands of high precision application requirements of LEOs. The high precision denotation model of satellite orbit dynamics based on physics parameter model and mathematics model which associates sparse parameter representation with time sequence analysis, nonlinear semi-parametric combined observation model based on system error parameters modeling and non-parametric component denotation of model error, and COD parameterized fusion model are established aiming at multi-satellite high precision COD based on bi-satellite positioning system and low earth orbiters (LEOs). Then parameters estimation algorithms of the former two kinds of models and the combined estimation algorithm of parameterized fusion model are designed. Theoretic analysis and simulated computation results show that the high precision denotation method of sparse parameters model and the optimized modeling method of observation model considering model error can improve modeling precision, and combined estimation algorithm of parameterized fusion model can synchronously ameliorate orbit determination precision ulteriorly.