Yang Yuanxi, Liu Li, Li Jinlong, Yang Yufei, Zhang Tianqiao, Mao Yue, Sun Bijiao, Ren Xia
State Key Laboratory of Geo-Information Engineering, Xi'an 710054, China; Xi'an Research Institute of Surveying and Mapping, Xi'an 710054, China.
Beijing Satellite Navigation Center, Beijing 100094, China.
Sci Bull (Beijing). 2021 Oct 30;66(20):2135-2143. doi: 10.1016/j.scib.2021.06.013. Epub 2021 Jun 13.
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 global 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 constellation. 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 accuracies of single and dual frequency BDSBAS are better than 3 and 2 m, respectively; the positioning accuracy 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.
北斗全球导航卫星系统(BDS-3)不仅具备常规的定位、导航和授时(PNT)功能,还提供特色服务。本文将这些特色服务分为基于地球静止轨道(GEO)卫星和中地球轨道(MEO)卫星的特色服务。前者指的是由区域短消息通信服务(RSMCS)、无线电测定卫星服务(RDSS)、基于北斗卫星的增强服务(BDSBAS)以及通过B2b信号的卫星精密单点定位服务(B2b-PPP)组成的区域服务。后者指的是由全球短消息通信服务(GSMCS)和基于MEO卫星的搜索救援(MEOSAR)服务组成的全球服务。本文重点描述这些特色服务并评估其性能。结果表明,星间链路(ISL)对整个星座的轨道确定和时间同步精度提升有很大贡献。与其他一些最终产品相比,BDS-3精密轨道和广播时钟的均方根(RMS)分别为25.1厘米和2.01纳秒。单频定位精度优于6米,广义RDSS的定位精度通常优于12米。对于特色服务,RSMCS和GSMCS的成功率分别优于99.9%和95.6%;单频和双频BDSBAS的定位精度分别优于3米和2米;B2b-PPP的定位精度优于0.6米,收敛时间通常小于30分钟;单站测试表明MEOSAR的成功率优于99%。由于BDS-3星座中实现了星间链路,全球特色服务的性能和能力得到了显著提升。