A long-term analysis of signal-in-space range error (SISRE) is presented for all healthy Galileo satellites, and the first pair of full operational capability satellites in wrong elliptical orbits. Both orbit and cloc...A long-term analysis of signal-in-space range error (SISRE) is presented for all healthy Galileo satellites, and the first pair of full operational capability satellites in wrong elliptical orbits. Both orbit and clock errors for Galileo show an obvious convergence trend over time. The annual statistical analyses show that the average root mean squares (RMSs) of SISRE for the Galileo constellation are 0.58 m (2015), 0.29 m (2016), 0.23 m (2017), and 0.22 m (2018). Currently, the accuracy of the Galileo signal-in-space is superior to that of the global positioning system (GPS) Block IIF (0.35 m). In addition, the orbit error accounts for the majority of Galileo SISRE, while the clock error accounts for approximately one-third of SISRE due to the high stability of the onboard atomic clock. Single point positioning results show that Galileo achieves an accuracy of 2-3 m, which is comparable to that of GPS despite the smaller number of satellites and worse geometry. Interestingly, the vertical accuracy of Galileo, which uses the NeQuick ionospheric model, is higher than that of GPS. Positioning with single frequency E1 and E5 show a higher precision than E5a and E5b signals. Regarding precise point positioning (PPP), the results indicate that a comparable positioning accuracy can be achieved among different stations with the current Galileo constellation. For static PPP, the RMS values of Galileo-only solutions are within 1 cm horizontally, and the vertical RMSs are mostly within 2 cm horizontally. For kinematic PPP, the RMSs of Galileo-only solutions are mostly within 4 cm horizontally and 6 cm vertically.展开更多
空间信号测距误差(Signal-In-Space Range Error,SISRE)描述卫星广播星历误差和钟差参数误差在用户平均星站方向的投影,是影响用户定位授时精度的关键因素.本文以事后精密轨道和钟差参数为基准,分别评估Galileo,GPS和BDS-3卫星的广播星...空间信号测距误差(Signal-In-Space Range Error,SISRE)描述卫星广播星历误差和钟差参数误差在用户平均星站方向的投影,是影响用户定位授时精度的关键因素.本文以事后精密轨道和钟差参数为基准,分别评估Galileo,GPS和BDS-3卫星的广播星历轨道用户测距误差(User Range Error,URE)、钟差参数误差、SISRE的大小和特征.结果表明,Galileo,GPS,BDS-3的SISRE分别为0.14,0.49,0.35 m.三者的广播星历轨道URE分别为0.14,0.27,0.09 m.三者的钟差参数误差分别为0.14,0.41,0.35 m.Galileo广播星历径向轨道误差和钟差参数误差之间具有很强的相关性.两者相互抵消,可有效降低Galileo卫星的SISRE.不同类型GPS卫星的钟差参数误差和SISRE有明显区别.随着GPS卫星的更新换代,其钟差参数误差和SISRE会逐步降低.BDS-3卫星具备与GPS和Galileo卫星显著不同的特征:(1)BDS-3卫星广播星历轨道径向误差和钟差参数误差的相关性较小,自洽性较差;(2)BDS-3卫星广播星历轨道URE较小,而钟差参数误差较大.其中,BDS-3卫星的广播星历轨道URE小于Galileo和GPS,但是其钟差参数误差对SISRE的贡献显著大于Galileo和GPS.通过比对上述卫星的SISRE大小及特征,指出提高钟差参数精度是提高BDS-3卫星空间信号精度的关键.展开更多
基金the National Natural Science Foundation of China(No.41774034)the National Key Research and Development Program of China(No.2016YFB0501803,No.2017YFB0503402).
文摘A long-term analysis of signal-in-space range error (SISRE) is presented for all healthy Galileo satellites, and the first pair of full operational capability satellites in wrong elliptical orbits. Both orbit and clock errors for Galileo show an obvious convergence trend over time. The annual statistical analyses show that the average root mean squares (RMSs) of SISRE for the Galileo constellation are 0.58 m (2015), 0.29 m (2016), 0.23 m (2017), and 0.22 m (2018). Currently, the accuracy of the Galileo signal-in-space is superior to that of the global positioning system (GPS) Block IIF (0.35 m). In addition, the orbit error accounts for the majority of Galileo SISRE, while the clock error accounts for approximately one-third of SISRE due to the high stability of the onboard atomic clock. Single point positioning results show that Galileo achieves an accuracy of 2-3 m, which is comparable to that of GPS despite the smaller number of satellites and worse geometry. Interestingly, the vertical accuracy of Galileo, which uses the NeQuick ionospheric model, is higher than that of GPS. Positioning with single frequency E1 and E5 show a higher precision than E5a and E5b signals. Regarding precise point positioning (PPP), the results indicate that a comparable positioning accuracy can be achieved among different stations with the current Galileo constellation. For static PPP, the RMS values of Galileo-only solutions are within 1 cm horizontally, and the vertical RMSs are mostly within 2 cm horizontally. For kinematic PPP, the RMSs of Galileo-only solutions are mostly within 4 cm horizontally and 6 cm vertically.
文摘空间信号测距误差(Signal-In-Space Range Error,SISRE)描述卫星广播星历误差和钟差参数误差在用户平均星站方向的投影,是影响用户定位授时精度的关键因素.本文以事后精密轨道和钟差参数为基准,分别评估Galileo,GPS和BDS-3卫星的广播星历轨道用户测距误差(User Range Error,URE)、钟差参数误差、SISRE的大小和特征.结果表明,Galileo,GPS,BDS-3的SISRE分别为0.14,0.49,0.35 m.三者的广播星历轨道URE分别为0.14,0.27,0.09 m.三者的钟差参数误差分别为0.14,0.41,0.35 m.Galileo广播星历径向轨道误差和钟差参数误差之间具有很强的相关性.两者相互抵消,可有效降低Galileo卫星的SISRE.不同类型GPS卫星的钟差参数误差和SISRE有明显区别.随着GPS卫星的更新换代,其钟差参数误差和SISRE会逐步降低.BDS-3卫星具备与GPS和Galileo卫星显著不同的特征:(1)BDS-3卫星广播星历轨道径向误差和钟差参数误差的相关性较小,自洽性较差;(2)BDS-3卫星广播星历轨道URE较小,而钟差参数误差较大.其中,BDS-3卫星的广播星历轨道URE小于Galileo和GPS,但是其钟差参数误差对SISRE的贡献显著大于Galileo和GPS.通过比对上述卫星的SISRE大小及特征,指出提高钟差参数精度是提高BDS-3卫星空间信号精度的关键.