--- title: "When the backhaul is a satellite | Nexus Observatory" description: "For a remote site, the satellite is not a backup; it is the network. Since Release 17, the cellular standard includes satellites as part of the radio access…" url: https://observatory.global/stories/ntn-backhaul/ publisher: Nexus Observatory Inc. updated: 2026-10-31 --- [Stories](https://observatory.global/stories/)System: Satellite backhaul # When the backhaul is a satellite For a remote site, the satellite is not a backup; it is the network. Since Release 17, the cellular standard includes satellites as part of the radio access network itself1. **Systems**: LEO backhaul, Non-terrestrial networks, Gateway stations **Toward 2030**: Direct-to-device and regenerative payloads **Figures**: 4, map story, data story, simulator, systems diagram Go to the references **01** Map story ## Site, satellite, gateway. A remote site’s terminal links to a satellite in low orbit, which relays to a gateway hundreds or thousands of kilometres away, and from there to the core network. The arcs here run from a northern site to a gateway in the south; the orbit passes over both. Figure as text: A remote site, a gateway and a low-orbit relay A wireframe globe over North America with a remote site, a gateway station, an arc between them and a low orbit with its ground track. - Remote site (68.4° N, 133.7° W) - Gateway (49.3° N, 123.1° W) - Core network (43.7° N, 79.4° W) **02** Data story ## The delay budget. A bent-pipe relay adds two slant ranges of propagation. In low orbit that is milliseconds; in geostationary orbit it approaches a quarter of a second each way, which the standard’s timing advance and retransmission procedures have to absorb2. Figure as text: Propagation delay by orbit, user to gateway A bar chart of computed one-way user-to-gateway delays for five orbits. | Orbit | One-way delay | | --- | --- | | LEO 550 km | 7.5 | | LEO 1,200 km | 14.7 | | MEO 8,063 km | 70.3 | | MEO 20,200 km | 155.1 | | GEO 35,786 km | 260.6 | **03** Simulator ## Footprint and altitude. Each satellite serves the ground it can see above the elevation mask. A higher mask means shorter, cleaner paths and a smaller footprint; set both and read the slant range and delay3. Figure as text: Footprint and delay of a backhaul satellite A section through the Earth with a satellite above it and its footprint arc in red. | Altitude | 550 km | | --- | --- | | Elevation mask | 25 ° | | Footprint radius | 940.5 km | | Slant range at the mask | 1,123.3 km | | One-way delay, nadir | 1.83 ms | | Bent-pipe delay, user to gateway | 7.49 ms | | Orbital period | 96 min | **04** Systems diagram ## Two paths out. A site with both a low-orbit and a geostationary terminal keeps a path when one fails, at the cost of delay. The waveform family used across satellite services makes the second terminal an ordinary one4. Figure as text: A remote site with two satellite paths A four-tier diagram: site equipment, the site router, two satellite paths, and the gateway and core. - **Site** : Local cell, Sensors - **Router** : Site router - **Space** : LEO, GEO - **Ground** : Gateway, Core 7 links. Scenarios: Low orbit in use; Low-orbit path lost. Figure 1 Map story **Orbit 550 km, 53°**: 95.5 min Figure 1. A remote site, a gateway and a low-orbit relay. A wireframe globe over North America with a remote site, a gateway station, an arc between them and a low orbit with its ground track. ## References 1. [Releases: the timeline of 3GPP Releases 17 to 21](https://www.3gpp.org/specifications-technologies/releases) . 3rd Generation Partnership Project, 2025. 2. [3GPP TR 38.821: Solutions for NR to support non-terrestrial networks](https://www.3gpp.org/DynaReport/38821.htm) . 3rd Generation Partnership Project, 2021. 3. Fundamentals of Astrodynamics and Applications, 4th edition. Vallado, D. A., Microcosm Press, 2013. 4. ETSI EN 302 307-2: DVB-S2 extensions (DVB-S2X). European Telecommunications Standards Institute, 2015. ## Related stories [Place: Orbit **Orbits as infrastructure** Low orbits are fast and crowded, high orbits slow and spacious. Every choice of altitude is a trade between delay, footprint and how long the satellite…](https://observatory.global/stories/orbit/) [Place: Rural village **A village at the end of the line** Where the fibre ends, a single mast, a satellite terminal and a handful of sensors decide whether a village is on the map of observation. Canada’s target is…](https://observatory.global/stories/rural-village/) [System: Resilient operations **When the links fail** Observing systems matter most on the days infrastructure fails. Designing for that day means local autonomy, stored power, store-and-forward delivery and…](https://observatory.global/stories/resilient-ops/) ## Where this applies [Space and satellite systems](https://observatory.global/space/)[Connectivity](https://observatory.global/connectivity/)[Edge compute & AI](https://observatory.global/edge-ai/)[Telecom](https://observatory.global/industries/telecom/)[Communities](https://observatory.global/industries/communities/)[Mining](https://observatory.global/industries/mining/)[Oceans](https://observatory.global/industries/oceans/)[Field tour: ground station](https://observatory.global/environments/ground-station/)[Field tour: orbit view](https://observatory.global/environments/orbit-view/) © 2026 Nexus Observatory Inc. **Legal** [Privacy notice](https://observatory.global/legal/privacy/) · [Terms of use](https://observatory.global/legal/terms/) · [Cookie policy](https://observatory.global/legal/cookies/) · [Accessibility](https://observatory.global/legal/accessibility/) · [Official languages](https://observatory.global/official-languages/) · [Notices](https://observatory.global/notices/) **Company** [About](https://observatory.global/about/) · [Open governance](https://observatory.global/consortium/) · [Contact](https://observatory.global/contact/)