【摘 要】
：
BeiDou Global Navigation Satellite System (BDS-3) not only performs the normal positioning,navigation and timing (PNT) functions,but also provides featured services,which are divided into geostationary orbit (GEO) and medium earth orbit (MEO) satellite-ba
【机 构】
：
State Key Laboratory of Geo-Information Engineering,Xi’an 710054,China;Xi’an Research Institute of S
论文部分内容阅读
BeiDou Global Navigation Satellite System (BDS-3) not only performs the normal positioning,navigation and timing (PNT) functions,but also provides featured services,which are divided into geostationary orbit (GEO) and medium earth orbit (MEO) satellite-based featured services in this paper.The former refers to regional services consisting of the regional short message communication service (RSMCS),the radio determination satellite service (RDSS),the BDS satellite-based augmented service (BDSBAS)and the satellite-based precise point positioning service via B2b signal (B2b-PPP).The latter refers to glo-bal services consisting of the global short message communication service (GSMCS) and the MEO satellite-based search and rescue (MEOSAR) service.The focus of this paper is to describe these featured services and evaluate their performances.The results show that the inter-satellite link (ISL) contributes a lot to the accuracy improvement of orbit determination and time synchronization for the whole constel-lation.Compared with some other final products,the root mean squares (RMS) of the BDS-3 precise orbits and broadcast clock are 25.1 cm and 2.01 ns,respectively.The positioning accuracy of single frequency is better than 6 m,and that of the generalized RDSS is usually better than 12 m.For featured services,the success rates of RSMCS and GSMCS are better than 99.9％ and 95.6％,respectively;the positioning accu-racies of single and dual frequency BDSBAS are better than 3 and 2 m,respectively;the positioning accu-racy of B2b-PPP is better than 0,6 m,and the convergence time is usually smaller than 30 min;the single station test shows that the success rate of MEOSAR is better than 99％.Due to the ISL realization in the BDS-3 constellation,the performance and capacities of the global featured services are improved significantly.
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