39. Analysis of BeiDou Signals on the Accuracy of Common-View Time Transfer

The BeiDou navigation satellite system is being in the initial period of providing service. Currently, this system is broadcasting three signals, narrow correlation, wide correlation and anti-multipath, on both I and Q branches of B1, B2 and B3 frequency. One can get the pseudo-range measurements publicly on the civil frequency with a corresponding receiver. This paper firstly analyzed the influence of different satellites types, GEO, MEO and IGSO in BeiDou constellation, on the precision of common view time transfer. The conclusion indicates that the one can achieve the best precision of common view time transfer with GEO satellites among the three different satellites types. Based on this conclusion, this paper further analyzes the impact of different observation types, C/A measurements on any frequency and assembled dual frequency observations of any two frequencies, on the precision of common view time transfer. The results of common view time transfer are evaluated with stability, accuracy and standard deviation of residuals. Except the combination of B2 and B3 and the wide correlation combinations of dual frequency, the results obtained from the other combinations of dual frequency observations perform better than that from any single frequency. The result of B1IA is better than other single frequency, the residual standard deviation is 2.32, the stability of million seconds is 3.18e-13 and the accuracy is 4.16e-13. Among the results of all the dual frequency observations, the combination of B1IA and B2IA provides the best precision with the standard deviation of residuals being 1.36, the stability of million seconds being 2.11e-13 and the accuracy being 5.71e-13.