低轨星座导航增强能力研究与仿真

低轨卫星星座具有几何图形变化快、落地信号功率强、全球天基监测覆盖等天然优势,可对中高轨全球导航卫星系统(Global Navigation Satellite System,GNSS)星座进行有效补充和增强,提升全球定位、导航与授时(Positioning,Navigation and Timing,PNT)服务的精度、完好性、可用性和抗干扰等能力,已成为下一代卫星导航系统重要的发展方向.本文总结了国内外低轨星座发展现状,对不同低轨星座进行了分析和设计,对低轨星座提升导航定位精度、加速精密单点定位(Precise Point Positioning,PPP)收敛、全球天基监测等导航增强能力进行了分析,重点论证了低轨星座突破现有中高轨GNSS技术瓶颈的机遇和体系增量能力,给出了相应的仿真分析结果,以期对我国低轨星座和北斗卫星导航系统的融合发展提供参考和建议.

Research and simulation of LEO-based navigation augmentation

The low Earth orbit(LEO)constellation satellite has natural features such as rapid geometric changes,strong signal power,and global space-based monitoring coverage.It can effectively supplement and enhance the global navigation satellite system(GNSS)in the mid-high orbit.Moreover,it can improve the accuracy,integrity,availability,and antiinterference capabilities of the positioning,navigation,and timing service,which has become an important development direction for next-generation satellite navigation systems.This paper summarizes the development status of the LEO constellations,designs the LEO constellations,and analyzes the navigation augmentation capabilities of the LEO constellations,such as improving the positioning accuracy,accelerating precision point positioning convergence,and global space-based monitoring.It focuses on illustrating the possibilities for the low-orbit constellation to break through the bottleneck of the existing mid-orbit and high-orbit GNSS technology and shows chances of the system incremental capabilities.The corresponding simulation results are specified to provide references and suggestions for the integration of the development of China’s low-orbit constellation and Beidou satellite navigation system.