Precise Orbit Determination of Navigation Satellite Using Joint Data from Regional Tracking Station and LEO

The precision of orbit determination for navigation satellites with regional distributed stations may be improved by introducing onboard GNSS observation data. The method of orbit determination combining the onboard data of LEO with the observation data of regional monitor stations is discussed. In order to validate this proposed approach and its performance, the observation data of seven GPS stations in China and onboard data of GRACE-A and GRACE-B during March 16–31, 2011 were collected and orbit determination experiments were carried out. The result shows that, compared with the result of seven stations, the visibility of GPS satellites is increased by about 14 %; meanwhile, the precision of GPS orbit expressed in RTN components is improved by about 35, 44, and 45 %, respectively; when introducing only GRACE-B, improvements in RTN components of 51, 60, and 62 % are achieved when both GRACE-A and GRACE-B are introduced and the visibility of GPS satellites is increased by 18 % in this case. The proposed approach will provide a new idea to improve the orbit determination accuracy of navigation satellite under the restriction of regional monitoring stations.