Modeling and Precision Analysis of Solar Radiation Pressure for BDS Hybrid Constellation

Since accurate satellite physical models are difficult to conclude, the empirical solar radiation models are key to improve the orbital accuracy. With the measurements from the regional network of BDS ground control, three widely-used solar radiation pressure(SRP) empirical models (T20 model, ECOM5 model, ECOM9 model) are used to determinate the orbits of the three kinds of satellites and evaluate the effectiveness. Result shows that ECOM9 model has a better performance when the sun closes to the GEO satellite during the spring (or autumn) equinox and the standard deviation (STD) of the difference between satellite clock offset from orbit determination and two-way satellite-ground clock offset is better than 2 ns, which is evidently improved over that of T20 model and ECOM5 model. For IGSO/MEO satellite, T20 model has a better performance whether during the period of satellite attitude switch or orbit-normal mode. Different from the previous research, the conclusion of this paper shows that for the different types of BDS satellites and the same satellite at different times, we should use different SRP model to obtain a higher orbit determination and prediction accuracy.