Research on the Combination of Station Coordinate Products Derived from Multiple Analysis Centers

This paper first gives a summarization of different combination strategies, and then the combination strategy for station coordinates and earth rotation parameters (ERP) based on solution level is introduced. The one-year products from nine analysis centers of International GNSS Service (IGS) are used to validate the combination method. As far as the differences between the combined solutions and the results of IGS are concerned, the combined coordinates, ERP and geocenter motion parameters show well agreement with IGS combination. The agreement of coordinate is 0.5 mm and 1.0 mm for horizontal and vertical, respectively. While the precision of pole motion and its rate are respectively about 7.0×10^-6" and 40.0×10^-6"/d, and the precision of length of day (LOD) parameter is better than 7.7×10^-6 s/d. The implemented program of station coordinates and ERP combination will be helpful for the international GNSS monitoring and assessment system (iGMAS) products combination.