BDSBAS时间基准互操作方法研究与性能测试

Research and Performance Assessment of BDSBAS Time System Interoperability

卫星导航星基增强系统(Satellite-Based Augmentation System,SBAS)由不同国家建设,所增强卫星星座和参考时间系统不尽相同,因此,星基增强系统时间基准之间的兼容互操作一直是国际民航组织(International Civil Aviation Organization,ICAO)星基增强系统标准研究中的重要技术问题。介绍了星基增强系统网络时(SBAS Network Time,SNT)的概念和研究现状,结合国际民航组织星基增强系统标准与建议措施(Standards and Recommended Practices,SARPs),对星基增强系统网络时间兼容互操作问题进行了分析和研究,并给出了目前最新的联合解决方案。在此基础上,对北斗星基增强系统地面状态进行了升级,并开展了服务性能初步测试。结果表明,北斗星基增强系统单频(Single Frequency,SF)星基增强系统网络时间和双频多星座(Dual-Frequency Multi-Constellation,DFMC)星基增强系统网络时间与参考全球导航卫星系统(Global Navigation Satellite System,GNSS)时间基准之间的最大偏差分别为37 ns和0.17μs,满足国际民航组织标准要求;服务性能基本符合APV-I等级要求,证明了北斗星基增强系统时间基准互操作的可行性和可靠性。

Since each SBAS is constructed by different countries, the augmented GNSS constellation and the reference time are not the same, the compatibility and interoperability between SBAS time systems has been one of the important issues in the SBAS standard research of the International Civil Aviation Organization(ICAO). The contribution introduces the concept and research status of the SBAS network time(SNT), combined with the formulation of ICAO SBAS Standards and Recommended Practices(SAPRs), analyzes and studies SNT compatibility and interoperability issues, and presents the latest joint solution. On this basis, the ground sub-system of the BeiDou Satellite-Based Augmentation System(BDSBAS) was upgraded, and preliminary service performance assessment was carried out. The results show that the maximum deviations between the BDSBAS single-frequency(SF) SNT and dual-frequency multi-constellation(DFMC) SNT and the reference GNSS time reference are 37 ns and 0.17 μs, respectively, which meet the ICAO standards. The service performance basically conforms to the APV-I level requirements, which proves the feasibility and reliability of the interoperability of BDSBAS SNT.