北斗三号系统卫星自主完好性监测技术

完好性对于全球卫星导航系统(GNSS)来说至关重要，关乎到其能否被放心应用。卫星自主完好性监测(SAIM)技术，是完好性监测技术发展的前沿趋势，国内外卫星导航系统均竞相发展。介绍了北斗三号系统SAIM技术设计与实现的重要意义，从功能设计和实现原理两个方面，阐述了北斗三号SAIM技术体制。针对SAIM实际在轨监测数据的正态分布特性服从程度和长期稳定性等问题，随机选取某一颗中圆轨道(MEO)卫星自2020年7月31日北斗三号系统正式开通服务以来至2021年7月31日连续1年期间的监测数据，得到真实在轨监测数据的分布特性。最后，提出了告警门限优化、分级告警策略设计、星历完好性自主监测等方面的后续发展必要性建议，旨在为北斗系统更好地为全球用户提供更优质的完好性服务提供参考。

Satellite autonomous integrity monitoring techniques for BDS-3

Integrity is very important for the global navigation satellite system(GNSS), which is related to whether it can be safely applied. Satellite autonomous integrity monitoring(SAIM) technology is the frontier trend of the development of integrity monitoring technology, so that all GNSS around the world are competing to develop it. This paper introduces the significance of the design and implementation of BDS-3 SAIM technology, and expounds the BDS-3 SAIM technology from two aspects of function design and implementation principle. Aiming at the problems of normal distribution characteristics and long-term stability of actual on-orbit monitoring data of SAIM, the monitoring data of a medium Earth orbit (MEO) satellite from July 31,2020 to July 31,2021 are randomly selected to obtain the distribution characteristics of real on-orbit monitoring data. Finally, the necessary suggestions for the follow-up development of alarm threshold optimization, hierarchical alarm strategy design and autonomous monitoring of ephemeris integrity are put forward, aiming to provide reference for Beidou system to provide better integrity services for global users.