全球导航卫星系统(Global Navigation Satellite System, GNSS)时间传递技术以其低成本、高精度、广覆盖范围等特点, 广泛应用到高精度时频领域。传统卫星共视技术利用全球卫星导航时间比对标准(Common GNSS Generic Time Transfer Standard, CGGTTS)共视文件实现事后高精度时间传递, 很难实现实时时间传递。为满足数字换流站、电力物联网、移动通信等对实时、高精度时间传递的需求, 研究了基于北斗三号全球卫星导航定位系统(BDS-3)伪距观测数据的实时卫星共视技术, 开展了短基线和西安-三亚长基线北斗实时卫星共视时间传递实验来评估实时共视时间传递性能。实验结果表明北斗实时卫星共视时间传递精度优于1 ns, 可为时频系统、数字换流站等应用领域提供纳秒级时间同步和纳秒级时间溯源服务。

Global Navigation Satellite System(GNSS) time transfer techniques with low cost, high precision and wide coverage, are widely used in high precision time-frequency. Traditional satellite common-view (CV) technology uses Common GNSS Generic Time Transfer Standard(CGGTTS) file to realize post high-precision time transfer, and it is difficult to realize real-time time transfer. To meet the needs of digital converter station, power internet of things, mobile communication and etc. This paper studies real-time common-view time transfer based on the pseudo-range observations of the Beidou-3 global navigation and positioning system (BDS-3). Short baseline and Xi’an-Sanya long-baseline real-time CV time transfer experiments are carried out to evaluate the performance of real-time CV method. The results show that the precision of real-time CV time transfer based on BDS-3 is better than 1ns, and it can provide nanosecond time synchronization and nanosecond timing services for time-frequency system, digital converter station and some other applications.