时间频率学报

针对跟踪站对北斗三号全球导航卫星系统的跟踪卫星数量存在较大差异和变化，且观测数据质量良莠不齐的问题，基于国际GNSS服务（IGS）跟踪网、欧洲参考框架（EUREF）跟踪网以及澳大利亚地球科学局（GA）连续运行跟踪网三个主要的公开数据集组成的全球网观测数据，统计分析了北斗三号正式开通一年来各跟踪站接收不同北斗三号信号的卫星数量及最大PRN变化，并从数据完整率、周跳比、码伪距多路径误差以及可见卫星数4个指标评估了其中473个跟踪站一个月的观测数据质量。结果表明：截止到2021年7月31日，在统计的全球网范围内，能够接收到B1C/B2a、B1I/B3I双频观测值和B2b观测值的跟踪站数量分别为223个、516个和142个，其中，三者分别有97.8%、70.2%和99.3%的跟踪站能接收到18颗及以上的BDS-3卫星；能够接收全部BDS-3卫星的接收机及固件版本主要有JAVAD TRE＿3/3.7.10、TRIMBLE ALLOY/5.44/5.45、SEPT ASTERX4/4.8.2、SEPT POLARX5/5.4.0、LEICA GR30/4.50/7.710、LEICA GR50/4.50.274、STONEX SC2200/2.12-210201、CHC P5E/1.2.5RUS;473个跟踪站中，71%的跟踪站数据完整率为100%,64.1%的跟踪站周跳比（CSR）不大于1,90.7%的跟踪站码伪距多路径误差分布在0.2～0.6 m；分别筛选出数据质量较优的208个能接收B1I/B3I双频信号的跟踪站，和134个能接收B1C/B2a双频信号的跟踪站。研究结果可为基于北斗三号的导航定位授时试验、全球网数据分析等提供一定参考。

In view of the large differences and changes in the number of tracking satellites used by tracking stations for Beidou-3 Global Navigation Satellite System and the uneven quality of the observation data, the global network observation data is based on three major open datasets, namely, the International GNSS Service(IGS) Tracking Network, the European Reference Framework(EUREF) Tracking Network and the Australian Geological Sciences Agency(GA) Continuous Operations Tracking Network. The number of satellites receiving different BDS-3 signals and the change of maximum PRN number for each tracking station during the year since BDS-3 was officially opened are analyzed. The quality of one month's observation data of 473 tracking stations is evaluated based on four indicators: data integrity rate, cycle skip ratio, code pseudo-range multipath error and number of visible satellites. The results showed that as of 31 July 2021, 223, 516 and 142 tracking stations can receive B1C/B2a, B1I/B3I dual-frequency and B2b observations in the above-mentioned global network, of which 97.8%, 70.2% and 99.3% can receive at least 18 BDS-3 satellites, respectively. Receiver and firmware versions capable of receiving all BDS-3 satellites mainly include JAVAD TRE＿3/3.7.10, TRIMBLE ALLOY/5.44/5.45, SEPT ASTERX4/4.8.2, SEPT POLARX5/5.4.0, LEICA GR30/4.50/7.710, LEICA GR50/4.50.274, STONEX SC2200/2.12-210201, CHC P5E/1.2.5RUS. Among the 473 tracking stations, 71% have 100% data integrity, 64.1% have no more than 1 cycle-slip ratio(CSR), and 90.7% have 0.2-0.6 m pseudo-range multipath error. 208 tracking stations capable of receiving B1I/B3I dual-frequency signals and 134 tracking stations capable of receiving B1C/B2a dual-frequency signals were selected with better data quality. The results can serve as references for BDS-based navigation, positioning and timing(PNT) service.