Evaluation the Performance of Space-borne Atomic Clock and the Positioning Accuracy of BDS2/3 in China Region

In this article, an assessment of the capabilities of the Beidou Navigation Satellite System (BDS) and the Global Positioning System (GPS) has been conducted. The findings indicate a significant improvement in the precision and atomic clock capability of BDS-3, attributable to the incorporation of a next-generation atomic clock, albeit still falling short of the performance demonstrated by GPS. Furthermore, a motion Precise Point Positioning (PPP) experiment was conducted within the Chinese territory, facilitating a comparative analysis of the positioning characteristics between BDS and GPS. The results reveal that in terms of North and East directions, the location precision of BDS-2/BDS-3 is nearly comparable to GPS. In the upward direction, BDS surpasses GPS, owing to the more visibility of BDS satellites and their more rational geometric configuration. Additionally, the concurrent utilization of BDS-2 and BDS-2/BDS-3 can enhance the operational capability of BDS. In summary, the combined positioning capability of BDS-2/BDS-3 is conducive to increasing the overall service efficiency of BDS.