5G-ALLSTAR: Beyond 5G Satellite-Terrestrial Multi-Connectivity

This paper presents a summary of the results of the 5G-ALLSTAR project. It describes the enablers that have been developed and validated and will help make 5G and beyond satellite-terrestrial multi-connectivity (MC) a reality in the near future. We proposed and evaluated solutions for critical aspects of the integration of non-terrestrial networks into a 5G and beyond terrestrial network. The OpenAirInterface implementation of the 5G physical layer (PHY) has been upgraded to meet the satellite radio channel constraints. We addressed the issue of co-tier interference between satellite and terrestrial systems. We designed and implemented customized 5G Physical layer, specifically adapted for terrestrial-satellite spectrum sharing. On top of the dedicated beam-forming and hardware design, we validated the full potential of MC by conceiving and testing our proposed resource allocation algorithms based on a custom multipath TCP protocol. The contribution of MC in vehicular use cases has been demonstrated onsite by implementing a terrestrial 5G PHY in conjunction with a satellite/terrestrial traffic controller. Finally, radio resource management solutions were examined. Thanks to these tools, the presence of industry partners in the consortium and to an active participation in standardization, the 5G-ALLSTAR project is an accelerator for the integration of non-terrestrial networks in 5G and beyond.