Non-terrestrial networking (NTN) refers to any network that involves space or airborne elements, including satellite communication networks, high-altitude platform systems (HAPS), and air-to-ground networks

Satellite communication networks utilise spaceborne platforms, such as low Earth orbiting (LEO) satellites, medium Earth orbiting (MEO) satellites and geosynchronous or geostationary Earth-orbiting (GEO) satellites. 

In recent years, alongside technical advancements in antennas, chipset size, power consumption, reusable rockets and satellite size, there has been a renewed interest in the use of LEO networks with large satellite constellations to provide voice and data services, particularly to rural or remote areas.

 With more demand for higher bandwidth and lower latency, Non-Geostationary Orbit (NGSO) satellites have also started to emerge and help serve different use cases: mainly broadband communications, connectivity to enable the Internet of Things industrial applications, provision of backhaul for terrestrial networks, and advanced earth observation applications. 

Telecoms satellite

HAPS are airborne platforms which can include aeroplanes, balloons, and airships. The base station element in a typical terrestrial network is relocated to the sky, creating International Mobile Telecommunications base stations (HIBS) which can cover large areas of land and therefore users with a single flying platform. A HIBS system provides mobile service in the same frequency bands as terrestrial mobile networks and can be used to provide both fixed-mobile connectivity for end users and transmission links between the mobile and core networks for backhaul. It can enable wireless broadband deployment in remote or dense urban areas, and the ability to provide telecom services with minimal ground network infrastructure makes it suitable for rapidly deployable disaster recovery communications and temporary coverage of entertainment events. The use of these networks has been enabled by advancements in array antennas, solar panel efficiency levels and battery densities. As part of clusters, they can become a permanent feature in the communications infrastructure.

Air-to-ground networks provide in-flight connectivity to aeroplanes via ground stations which play a similar role as base stations in terrestrial mobile networks. The antennas of the ground stations are up-tilted towards the sky, and the distances between the ground stations are much larger than that of terrestrial mobile networks. 

Satellite connectivity has played a relatively minor role to date in the telecoms sector, but the ubiquitous coverage that it supports will be increasingly business-critical for operators, especially in IoT applications. However, there are some challenges including understanding how they sit alongside and integrate with terrestrial network technologies and consolidating commercial opportunities and providing the market viability of use cases. There are also more practical considerations such as space traffic management and access to spectrum frequencies.

NTNs also require policies on both the physical media (space and airspace) and telecoms services (mainly spectrum licensing). The International Telecommunications Union (ITU) currently works with administrations to help regulate and coordinate satellite orbits and spectrum use, but this is very much in its infancy and governments will likely then want to define their regulatory frameworks.

Standards development will also be important to ensure widespread adoption and sustainability.  This work has already started: 3GPP Release 17 supports NTN elements and 6G is adopting NTN as a core element. This convergence of standards—alongside improvements in satellite costs and latency—will broaden the role of satellite communications within fixed and mobile network technologies.

The UK has a real opportunity to take a lead in Non-Terrestrial Networking (NTN) industrial developments.

As Chair of the NTN Expert Working Group, I'm committed to developing a UK strategy that brings academia and industry together to form a roadmap from 5G to 6G, and addresses the key NTN technologies that industry can focus on.  Putting the UK in the driving seat for NTN.”

Barry Evans

Professor of Satellite Communications - Institute for Communications Research (ICS) and 6GIC, University of Surrey

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Our focus areas
  • Opportunities for NTN
  • Diversification of supply chains
  • NTN integration
  • Barriers