基于低轨互联网星座的全球导航增强——机遇与挑战

LEO Broadband Satellite Constellations Based Global Navigation Augmentation:Opportunity and Challenge

针对当前卫星导航发展的瓶颈问题,结合当前低轨互联网星座蓬勃发展的趋势,提出了基于低轨互联网星座的全球导航增强系统建设方案。从新兴用户群体对PNT性能的需求、低轨互联网星座的优势、建设成本优势以及通导融合优势等角度出发,分析了低轨全球导航增强的发展机遇。从频率资源、功率资源以及收敛时间三方面,总结了发展低轨全球导航增强系统面临的挑战。在此基础上,为系统体制、信号体制以及系统建设提出了发展建议。最后给出了总结认为低轨全球导航增强采用天基监测+信号增强体制,信号落地功率有望提升15~30dB,收敛时间缩短至秒级,信号频段向Ka频段扩展,最终实现城市挑战性环境下快收敛、高精度、高完好、高安全、高可用的PNT目标。

Considering that the booming development trend for LEO broadband satellite constellations and the current bottleneck of satellite navigation service performance,a global navigation augmentation system based on LEO broadband satellite constellations is proposed.The development opportunity of the global navigation augmentation is analyzed,including the PNT performance requirement of the emerging users,the advantages of LEO broadband satellite constellations,the construction cost and the fusion of communication and navigation.Then the development challenges of the global navigation augmentation are discussed,in terms of frequency source,power source and convergence time.Based on this,the development roadmaps of system architecture and signal structure are suggested.Finally,the following conclusions are summarized:the space based monitoring and signal augmentation can be adopted by the global navigation augmentation,and the signal received power on ground can be increased by 15~30dB;the convergence time can be reduced to several seconds,and the signal frequency can extend to Ka band;the PNT service object of fast convergence,high precision,high integrity,high security,high availability under the challenging environment will be achieved.