Next-generation global satellite system with mega-constellations

Mega satellite constellations in low earth orbit (LEO) will provide complete global coverage; rapidly enhance overall capacity, even for unserved areas; and improve the quality of service (QoS) possible with lower signal propagation delays. Complemented by medium earth orbit (MEO) and geostationary earth orbit (GEO) satellites and terrestrial network components under a hybrid communications architecture, these constellations will enable universal 5G service across the world while supporting diverse 5G use cases. With an unobstructed line-of-sight visibility of approximately 3 min, a typical LEO satellite requires efficient user terminal (UT), satellite, gateway, and intersatellite link handovers. A comprehensive mobility design for mega-constellations involves cost-effective space and ground phased-array antennas for responsive and seamless tracking. An end-to-end multilayer protocol architecture spanning space and terrestrial technologies can be used to analyze and ensure QoS and mobility. A scalable routing and traffic engineering design based on software-defined networking adequately handles continuous variability in network topology, differentiated user demands, and traffic transport in both temporal and spatial dimensions. The space-based networks involving mega-constellations will be better integrated with their terrestrial counterparts by fully leveraging the multilayer 5G framework, which is the foundational feature of our hybrid architecture.