Precise Orbit Determination of CHAMP with Reduced-dynamic Method based on Satellite-borne GPS Technique

A great deal of continuous high-low satellite-to-satellite tracking observations can be collected with the satellite-borne GPS technique,which can be used to precisely determine orbits of low-earth-orbit satellites.CHAMP's precise orbit is determined from CHAMP′s satellite-borne GPS data with the zero-difference reduced-dynamic method,presents the processing of precise orbit determination and analyses the precision of orbit determintion.The experiment of precise orbit determination is done with the actual data.The result Compares with the post-processed science orbits of GFZ,and analyses the difference in X,Y,Z directions.The study shous that: the RMS difference in X,Y,Z directions are 0.053,0.054,and 0.050 m respectively.In general,the accuracy of the computed orbit is at centimeter level,and it reaches the required standard.