Understanding the basics of 5G for satellites: What is 5G NTN?

Understanding the basics of 5G for satellites: What is 5G NTN?

As demand for global connectivity continues to grow, extending 5G beyond terrestrial networks has become an increasingly important part of the telecommunications landscape. Satellite-enabled 5G is now viewed as a practical complement to terrestrial infrastructure, enabling coverage in remote, rural, and hard-to-reach areas where ground-based networks remain limited.

In recent years, standardisation efforts within 3GPP have moved 5G Non-Terrestrial Networks (5G NTN) from concept toward early implementation. This article explains the basics of 5G for satellites, what 5G NTN is, which satellite constellations can be used, and the key challenges that continue to shape satellite-based 5G deployments in 2026.

What is 5G NTN?

5G NTN, short for 5G Non-Terrestrial Networks, refers to the integration of satellite communications into the 5G system as defined by 3GPP. Rather than replacing terrestrial mobile networks, 5G NTN is designed to extend 5G coverage by allowing satellites to participate as part of the overall network architecture.

In practice, a 5G NTN system combines satellite constellations, ground-based network elements, and standardised 5G protocols. This enables user devices to connect via satellite while remaining aligned with the same core network, interfaces, and service principles used in terrestrial 5G deployments.

Since the introduction of NTN support in 3GPP Release 17, and its continued evolution in subsequent releases, the focus has increasingly shifted from feasibility toward performance optimisation, interoperability, and deployment realism.

Which satellite constellations can be used for 5G NTN?

5G NTN can be deployed using different satellite orbital regimes, each with distinct characteristics and trade-offs:

In current 5G NTN deployments and trials, most attention is focused on LEO and GEO systems. GEO satellites offer very wide coverage areas and enable terrestrial-like cell planning, while LEO satellites provide lower latency and improved link budgets due to their shorter distance from Earth.

Latency, defined as the time required for a signal to propagate through the network, remains a key performance consideration across all orbital regimes and continues to influence architectural choices in 5G NTN design.

Doppler effects and satellite motion

Unlike GEO satellites, both LEO and MEO satellites move rapidly relative to the Earth. This relative motion introduces Doppler effects, resulting in frequency shifts that can significantly impact radio performance if left unmanaged.

Modern 5G NTN implementations rely on software-based mechanisms to compensate for Doppler effects. These mechanisms dynamically adapt transmission parameters based on satellite movement, enabling stable communication links even under rapidly changing conditions. Doppler compensation remains a core focus area in ongoing 3GPP work and vendor implementations.

What are the key challenges of 5G for satellites?

Delivering 5G over satellite introduces constraints that do not exist in terrestrial networks. Several challenges remain central to 5G NTN system design:

• Line-of-sight requirements between satellites and user devices to close the link budget.
• Limited visibility windows in LEO constellations due to continuous satellite movement.
• Frequent satellite reselection, requiring user equipment to switch satellites without service interruption.
• Propagation delay, particularly in GEO systems, affecting latency-sensitive applications.
• Increased path loss, driven by long transmission distances.

Addressing these challenges requires careful coordination between radio design, protocol behaviour, and system architecture, rather than relying on satellite hardware alone.

How are the challenges of 5G NTN addressed?

Software plays a central role in enabling practical 5G NTN deployments. 5G NTN software protocols are responsible for managing latency, mobility, Doppler effects, and scalability across satellite networks.

Standardisation efforts led by 3GPP provide the framework that enables this. By defining common architectures, interfaces, and protocol behaviour, 3GPP ensures that satellite-based 5G systems can integrate with terrestrial networks while remaining interoperable across vendors and implementations.

In more recent releases, the emphasis has expanded toward performance tuning, deployment scenarios, and operational considerations. This reflects the industry’s gradual transition from early validation toward controlled trials and initial service deployments.

5G NTN in the 2026 connectivity landscape

By 2026, 5G NTN is no longer viewed purely as an experimental extension of 5G. While large-scale commercial deployment is still evolving, the technical foundations are now well defined, and real-world testing continues to refine performance and operational models.

As standardisation, software maturity, and satellite capabilities continue to advance, 5G NTN is expected to play an increasingly important role in delivering resilient, scalable, and globally available connectivity alongside terrestrial networks.