5G promises hyperconnectivity for modern societies, but without satellite communication it also risks increasing the digital divide. Satellite networks must be leveraged to bring the latest technology on an accelerated basis to everyone, everywhere, including areas that are not covered by 3G and 4G. During the Covid-19 pandemic, satellite communications were called upon for a range of uses including the rapid set-up of direct broadband connectivity to new medical facilities as well as to support tele-education and tele-work. These global connectivity services were available to all citizens, regardless of country, population density, or economic status, highlighting the non-discriminatory nature of satellite services.

The success of many 5G service deployments depends on unique requirements that can be met by satellite networks. These include wide area coverage that is vital to extend networks to low-density areas, one-to-many distribution and reliable, and resilient operations. In this regard, satellite networks can:

  • Extend the reach of limited terrestrial 5G networks to underserved areas and places that terrestrial networks cannot cover (on land, in the air, at sea);
  • Ensure service continuity for M2M/IoT devices and connected/autonomous vehicles by providing reliable communications and supporting software updates on moving platforms such as passenger vehicles, aircraft, ships, trains and buses;
  • Provide robust and secure 5G services for critical and mobile communications (incident response, public safety);
  • Optimise the efficiency of 5G networks by multicasting/broadcasting data;
  • Enhance existing fixed network links with hybrid connections.

The satellite industry has successfully demonstrated that satcom can support key features of the 5G ecosystem. Significant work is under way to develop 5G standards and necessary features to ensure the integration of satellite into the 5G ecosystem and vice versa, that is, 5G integration into satellite networks.

Enabling the integration of satellites into the 5G ecosystem

The 5G ecosystem provides a broad range of design flexibilities and capabilities to support wide-ranging scenarios. The development of open 5G standards will allow satellite companies to reduce the development, deployment and operational costs of satellite network solutions.

Multiple successful demonstrations have shown that satellites can support key technological features in 5G networks such as software-defined networking, network function virtualisation, and multi-access edge computing. They also provide integrated network management and orchestration, multi-link and heterogeneous transport, harmonised control planes, a common security framework, end-to-end network slicing, and caching and multicast capabilities for content.

The satellite industry actively contributes to 5G standardisation bodies such as 3GPP and ETSI, which are supported by a wide range of organisations from both the satellite and mobile industries as well as by professional and governmental stakeholders. Within the 3GPP radio access network (RAN), work is under way for incorporating non-terrestrial networks including satellites into the 5G radio access standards for both broadband access and IoT. The work is being undertaken in a phased manner, spanning Releases 15, 16, 17 and beyond. A new work item document has recently been approved to begin the normative work to address the specifications for 5G satellite access solutions based on 5G NR. In addition, 3GPP RAN approved a study item for satellites to be supported by the 3GPP narrow band internet of things (NB-IoT) as well as LTE-M standards. These technical developments and efforts to establish global standards will enable cost-effective deployment and integration of satellite solutions into the end-to-end 5G system for improved service delivery and wider network operations. This will ensure that the benefits of 5G networks are fully realised and broadly distributed.

Satellite use cases in the 5G ecosystem

Communication on the move

This use case is about providing high speed enhanced mobile broadband (eMBB) backhaul connectivity to individual satellite terminals in motion on planes, road vehicles, trains and vessels. Satellite terminals have the ability to pre-position content (such as video, HD/UHD TV, FOTA, as well as other non-video data for local storage and use) in an on-board cache across a large coverage area. The same capability also allows for the efficient backhauling of aggregated IoT traffic from moving platforms. This service is delivered by high speed, multicast-enabled satellite links direct to the plane, vehicle, train or vessel, from GEO or non-GEO satellites, complementing existing terrestrial wireless connectivity where service is not available. This work builds on the successful deployment and operation of pre-5G services such as Wi-Fi on aircraft.

Direct-to-premises connectivity – Hybrid multiplay

This use case extends 5G network service orchestration and management into homes and businesses. Satellite is being utilised to successfully deliver high speed broadband to over 2 million homes globally, and satellite television to hundreds of millions of households. In the 5G context, such capabilities can be combined into hybrid double-, triple- or quadruple-play bundles using a 5G “nano-cell” or even Wi-Fi inside the home as a means of redistributing high capacity satellite bandwidth, cloud access and satellite-delivered content among multiple home devices. All of this is managed by the 5G core network. These solutions can connect those that would otherwise not be connected. They can also be deployed in conjunction with available terrestrial connectivity to reduce terrestrial bandwidth consumption for video content. The demand for satellite-delivered broadband and/or television can be higher in places that have some (but perhaps inadequate) terrestrial connectivity

Direct connectivity to end-devices

Satellites already provide direct connectivity to end-user devices, even in hard-to-reach areas such as mountainous regions where terrestrial networks are unable or unwilling to offer service due to challenging geography, prohibitive infrastructure deployment costs or mobility reasons (such as on ships). Satellite connectivity builds on solutions that use standard chipsets and enhanced antennas to operate such as IoT devices, as well as end-user devices that can roam between mobile terrestrial wireless and satellite operations. IoT-type services over satellite are not new and this is an area that is seeing significant new investment and innovation. The industry is also working to ensure that the same user equipment will be able to access both terrestrial and non-terrestrial access technologies so that end-users can benefit from extended service reach, reliability and resilience. Moreover, the integration of satellite with 5G will ensure seamless service continuity through hand-over between the coverage areas of non-terrestrial and cellular networks as well as improved performance through multi-connectivity procedures.

Direct-to-premises connectivity backhauling and tower feed (cell site backhaul and content distribution)

This satellite use case provides high capacity backhaul connectivity to individual 5G cell sites, enabling efficient content distribution directly to these sites. Instead of providing middle-mile connectivity to a 5G aggregation point (as in trunking and head-end use that follows), satellites can directly connect individual cell sites and base stations. This is a natural extension of their role in 2G, 3G and 4G mobile networks. Mobile network operators today use various combinations of individual cell site backhaul and aggregated backhaul (trunking) via satellite to cost effectively upgrade and expand the coverage of mobile networks. Today’s HTS and tomorrow’s VHTS systems provide high capacity connections needed to perform the same function for emerging 5G networks. Similarly, the tower feed extends satellite’s capabilities as an efficient multi-cast distributor of common content by moving such content even closer to the network edge, that is, to the cell site, rather than an aggregation point, in much the same way that satellite direct-to-home television is an extension of video distribution to cable head-ends. Content delivery networks in 5G can be deployed all the way out to network edge at individual cell sites and still be efficiently fed via satellite multicast over a wide area.

Trunking and head-end feed – Aggregated mobile backhaul and content distribution

This use case is similar to the previous, except that it expands 5G connectivity by providing high-throughput and efficient multicast middle-mile satellite connectivity to aggregation nodes near the edge of 5G networks and not to the cell sites themselves. For trunking (or aggregated backhaul), a satellite link is used for high capacity backhaul of data (whether video, eMBB, IoT or other data) at one or more points in the network that aggregate the traffic of multiple 5G cell sites. In a typical deployment, mobile traffic from multiple base stations is aggregated (such as via fixed microwave) to a satellite terminal, which then carries the traffic to and from the network core. This can be paired with head-end feed (or content delivery or content pre-positioning or content caching), which uses the same satellite link to multi-cast commonly accessed content to these aggregation points where it can be cached and/or retransmitted to the 5G user requesting that content. 5G networks will need efficient multicast distribution of commonly accessed content to the network edge to achieve the required perceived lower latency.

Conclusion

By incorporating satellites into the 5G ecosystem, the benefits of next-generation 5G connectivity can be made available to all users wherever they are. To successfully ensure that the 5G ecosystem includes all technologies, governments must embrace a standards-based, technology-neutral approach to regulation. This will enable the timely and widespread deployment of 5G. By working together, policymakers and industry can improve the lives of all citizens by bringing them the full benefits of next-generation 5G communication. s

Based on a white paper, “Satcom Services: An Integral Part of the 5G Ecosystem”, by the EMEA Satellite Operators Association