Reducing the Influence of Gravity Model Error on Precise Orbit Determination of Low Earth Orbit Satellites

Based on the orbit integration and orbit fitting method,the characters of the influence of the gravity model with different precision on the movement of low earth orbit satellites was studied.The way and the effect of reducing the influence of gravity model error to CHAMP and GRACE satellites orbits by liner and periodical empirical acceleration model and so-called "pseudo-stochastic pulses" mode were also analyzed.