The European Space Agency (ESA), together with a consortium of European satellite industry, terrestrial technology providers and terrestrial mobile network operators, have released a study to investigate and optimise routing protocols enabling efficient operation of 6G Multi-orbit Non-Terrestrial Networks (NTN).
The project is led and funded by ESA’s Connectivity and Secure Communications’ Space for 5G/6G and Sustainable Connectivity programme line. The study was primed by Eurescom, in collaboration with Fraunhofer FOKUS, Airbus Defence and Space and D-Telekom.
Developed through ESA’s 6G SmartSat project, the study proposes novel routing solutions to seamlessly integrate space-based networks with terrestrial communication systems in the most efficient and adaptable manner. It aims to contribute to the goal of offering advanced connectivity for citizens and industries across ESA Member States and the globe, wherever the location.
With the widespread adoption of 5G as a communications standard, satellite constellations have emerged as viable alternatives and complement terrestrial networks. They offer extensive and reliable communications across a broad spectrum of users and applications, providing commercial, business and government connectivity services, as outlined in ESA’s 5G-IS white paper.
These constellations are already equipped with inter-satellite links and smart payloads capable of supporting Radio Access Network (RAN), core network functionalities and edge computing to form complex space-based networks. The satellite networks are characterised by overlapping layers of multi-orbit, grid-like topologies (how nodes in a network are connected) that undergo frequent, yet predictable, changes. It is viewed that challenges that come with these technologies will be addressed by 3GPP 5G Release 20/6G Release 21 standards.
The NTN networks are further impaired by weather effects that impact service and/or feeder links. These characteristics cause such networks to significantly differ from Terrestrial Networks, requiring new routing strategies.
To cope with these challenges, the study introduces a novel topology semantic routing protocol for multi-orbit NTN networks. The proposed architecture adheres to the principles of 3GPP services requirements, while accommodating the unique topological infrastructure constrains of multi-orbit NTN. It mitigates the continuous changes impacting the links quality or the neighbour satellite nodes status. To further increase the efficiency, the proposed solution can be used in combination with existing low-footprint routing solutions, such as pre-defined centralised routing for regular topologies, segment or geographical routing protocols.
“ESA is proud to be working with our industry partners to evolve and develop key 6G NTN technologies, which have the potential to enhance lives and businesses across our Member States,” said Antonio Franchi, Head of ESA’s Space for 5G/6G and Sustainable Connectivity programme. “This study showcases the real impact that we can have, with evolving business cases to be made across the various sectors, we look forward to realising the potential of 6G NTNs and their complementing role with existing TNs.”
“6G SmartSat activity holistically addresses the design of 6G multi-orbit NTN networking architectures. The study follows a co-design approach involving representatives of satellite and terrestrial sectors to identify, categorise, and prioritise the use cases better served by satellite constellations under technical and market fit criteria. The activity provides a first-in-kind contribution to the NTN sector detailing technology roadmap and tools necessary for validation of future 6G multi-orbit NTN networks,” said ESA’s Maria Guta, Senior 5G/6G Satellite Solutions Architect.
Read the white paper in full.
