基于iGMAS的国家标准时间精密授时系统

UTC是国际标准时间.UTC(NTSC)是UTC的物理实现之一,是我国的国家标准时间,也是我国一切授时业务的基础.目前,广泛应用的GNSS授时精度可达10～50ns.随着现代信息社会的快速发展,数十纳秒的授时精度及事后处理的工作模式已无法满足需求.针对上述问题,设计了基于iGMAS的国家标准时间精密授时系统(PTS).PTS的基本原理为:服务端基于iGMAS平台生成实时轨道及以UTC(NTSC)为参考的实时卫星钟差,用户端结合实时产品及伪距、载波相位观测数据,解算本地钟与UTC(NTSC)偏差.此外,搭建了PTS原型系统并展开测试分析,测试结果显示,基于PTS原型系统,各用户站授时精度均优于1ns.与GNSS授时技术相比,PTS将授时精度提高了1～2个量级,且基于国家标准时间授时,成本低廉,易于实现,具有应用前景.

National Time Standard Precise Time Service System Based on iGMAS

As one of the physical implementations of the international time standard UTC, UTC(NTSC) is the time standard of China and the foundation for time services around the China. At present, with precision up to 10~50ns, GNSS time services are widely used. With the rapid development of modern information society, the time service precision and the working mode of post-processing can not meet the demand any more. To solve the above problems, UTC(NTSC) precise time service system (PTS) based on iGMAS is designed. The basic principle of PTS is as follows: the server generates real-time orbits and real-time satellite clocks with UTC(NTSC) as reference based on iGMAS platform, and the user calculates the deviation between local clock and UTC (NTSC) by combining real-time products and pseudorange and carrier phase observation data. Moreover, prototype system is constructed and tested. Real-time online test result shows that, based on PTS prototype system, the time service precision of each user station is better than 1ns. Compared with GNSS time service technology, PTS improves the time service precision by 1~2 orders of magnitude. At the same time, the system is cheap and easy to implement and can meet the requirement of high precision UTC-based time service.