The First Realization of BeiDou Coordinate System and Its Assessment

摘要

The BeiDou Navigation Satellite System (BDS) has used the BeiDou Coordinate System (BDCS) as its geodetic reference system since December 2017. After a brief description of the background, definitions of the origin, scale, and orientation of BDCS are given, which are consistent with China's Geodetic Coordinate System 2000 (CGCS2000). Then the first realization of the BDCS aligning with the International Terrestrial Reference Frame 2014 (ITRF2014) is addressed. Coordinates at epoch 2018.0 and velocities at eight BDS monitoring stations were obtained achieved by processing four-phase GPS data for a global navigation satellite system (GNSS) network, including the monitoring stations, and by the frame alignment and linear regression fitting of station coordinate series. Assessment of the precision of the coordinates and Helmert parameters with respect to ITRF2014 reveals that the differences between the first frame of BDCS and ITRF2014 are less than 1 cm, which is compatible with WGS84 (G1762), PZ-90.11, and the latest Galileo terrestrial reference frame.