WINNIPEG, Manitoba — The hoped for dream of cohesive broadband incorporating the entire communications ecosystem continues to push satellite and telecommunications networks closer together, and 5G is one key accelerant. A variety of related standards are making this possible, building on 3GPP’s Release 17 (Rel-17) in 2021, which opened 5G up to non-terrestrial networks for the first time and giving us 5G NTN. Here’s a look at how some of the main names and acronyms fit together.

5G Non-Terrestrial Network (5G NTN)

5G NTN is a branch of the 5G specifications that have been written to accommodate the unique aspects of satellites and high-altitude platform stations (HAPS). Most of those unique aspects involve the large distances between the terrestrial network and the satellites orbiting in space, and the speeds at which those satellites travel.

With terrestrial 5G, there is generally only a few kilometers distance between connection points, creating low latency, often as little as one millisecond. When you add satellites into the network, connection points can now be tens of thousands of kilometers away and can increase latency by a half-second, or 500 times the latency of the terrestrial network.

At the speeds satellites travel, the 5G NTN specifications have to accommodate the Doppler effect of the satellites’ movement. These speeds and distances are just two of the challenges satellite operators must overcome when trying to tap into the 5G terrestrial network.

Transparent Payload

In order for a satellite to be able to communicate with 5G networks on the ground, it has to be compatible with the 5G base stations, known as gNodeB in 4G architecture and broken into the RU, DU and CU in a 5G architecture. A satellite can do this in one of two ways: transparent payloads and regenerative payloads.

In a transparent payload scenario, the satellite acts as a simple transceiver, receiving signals and transmitting an amplified version of the signal with frequency conversion from uplink to downlink frequencies.

To achieve a transparent payload effect, where the satellite acts as a bent-pipe not caring about the type of signal, so the 5G base station has to be located within the satellite’s ground station or teleport. Currently, this is being put into practice by some satellite operators.

Regenerative Payload

Unlike a transparent payload that only amplifies signals, a regenerative payload “regenerates” the signals it receives via signal-processing techniques like demodulation, decoding, switching, encoding, and modulation before retransmitting the signal. This act of regeneration can counteract any attenuation of the uplink signal before it is downlinked to user terminals, providing improved signal performance and data throughput.

The main impetus for regenerative payloads is signal routing when you have constellations with inter-satellite links. With regenerative payloads, the satellite reads the signal’s header and figures out the best route to deliver it to its destination, which may require routing through other satellites. By giving satellites the functioning of routers, you are essentially building a 5G network in space.

The positives about turning satellites into routers, is that each individual signal can be routed anywhere using the best possible route for that signal. However, the challenges of taking the routing work from the ground station and putting it into the satellites themselves include increased satellite size, weight and power (SWaP) requirements. Since the routers would now be in space, it becomes problematic to make any major changes to them.

With shorter development times and life spans, LEO constellations are thought to be in a better position to take advantage of regenerative payloads than their GEO counterparts, which have longer development times and lifespans.

5G NR-Uu

This is the standard behind all new 5G base stations. Within the context of 5G networks, the Uu interface is the air interface between the user equipment (UE) and the radio access network (RAN). The Uu interface is responsible for the transmission of user data, control signaling, and other types of information between the UE and the gNodeB.

The Uu interface operates in the 5G frequency range, including sub-6 GHz frequencies and millimeter wave frequencies between 30 GHz and 300 GHz. In the context of 5G networks, the Uu interface uses technology like Orthogonal Frequency Division Multiplexing (OFDM) and Multiple-Input Multiple-Output (MIMO). It also utilizes protocol layers, including the physical layer, radio link control layer and MAC layer for managing access to shared wireless mediums.

5G Narrow Band-IoT

The Internet of Things (IoT) is essentially a network of devices connected to the internet via hardware and software that are able to share data and communicate with each other via an interface.

Many “smart” devices, like smart speakers, thermostats, homes, lightbulbs, etc., are part of the IoT because they have software embedded in them that allows them to communicate with the internet.

Increasingly, Industrial IoT is used in areas with limited terrestrial network connectivity. This is where satellite IoT can help pick up where terrestrial networks leave off for applications like optimizing crop yields, tracking livestock, remote monitoring of energy assets, smart electrical grid management and fleet tracking, for example.

There are companies using constellations of 5G nanosatellites, ultra low-cost sensors and narrowband IoT to extend the internet of things around the world. 5G’s role in the process has been to standardize the software connection to satellites. Some estimates have the market of IoT devices tripling to 10.6 billion by 2032.

ORAN

Open Radio Access Network (ORAN) standards allow for 5G network components from different brands to work together via standardized application programming interfaces (APIs), eschewing brands’ proprietary software.

With ORAN standards, operators could take an Ericsson 5G core and pair it with a Fujitsu radio unit, for example, and have them work seamlessly together via an API. ORAN standards allow for network builders to use the best-in-class components from multiple vendors rather than being locked into one single vendor.

ORAN promotes flexibility in 5G network building, and telecom leaders believe it will lead to reductions in capital and operational expenditures. Some 55% of telecom leaders have already indicated they are seriously considering implementing ORAN solutions, according to a survey by design and manufacturing firm Jabil. The same principal could theoretically be leveraged to integrate with satcom components and systems.

Cloud Native

Cloud computing’s flexibility and rapid deployment capabilities make it ideal for telecommunications. Free from the limitations of hardware-based architectures, cloud computing can host virtual network functions (VNFs) like virtualized routers, firewalls, wide-area network (WAN) optimization, and network address translation (NAT) services. Most of these services are run in virtual machines on virtualization infrastructure software.

Cloud native software can also host containerized network functions, which are software services that fulfill network functionalities while using cloud-native design principles, namely forgoing expensive proprietary hardware to house them.

In satcom, 5G is driving a move to software-defined networking (SDN) as it is one of the infrastructure pillars of 5G. As Luc-Yves Pagal Vinette, product marketing director for 5G service orchestration, network slicing, and service assurance at Amdocs, explained to Constellations, 5G itself is cloud native.

Cloud native computing allows for faster and less expensive scaling, while also providing the necessary speed to deal with more immediate needs, like having too much network traffic or the loss of a physical site. In these instances, a satcom provider could easily “spin up” a virtual modem to handle the excess traffic.

Organizations like the European Telecommunications Standards Institute (ETSI) have created standards for virtualized environments, like VNFs and containerized network functionalities. These include Architectural Framework and VNF Management and Orchestration (MANO), the latter of which addresses the management and orchestration necessary for provisioning VNFs and managing their lifecycles.

Network Slicing

The concept of network slicing within 5G networks is basically “walling off” a private network that exists within the public network so proprietary data only flows on the walled off portion of the network. Essentially, telecom providers can take their physical 5G networks and create virtualized “slices” numbering into the thousands, if necessary, to serve single enterprise customers or groups of customers who want to share data with each other while not having that data go through the public portion of the network.

Network slices can be tailor-made to meet enhanced mobile broadband, ultra-reliable low-latency communication and massive machine-type communication and they can be dedicated to specific services. These can include live broadcasting, virtual reality, automotive, healthcare, utilities, logistics and more.

Network slicing allows communications network operators to offer enterprises a unique and flexible service, customized to their specific needs. An example would include a sports stadium that provides network connectivity through a service provider to a range of stakeholders. The stadium might have a network slice for fans to upload social media content, another slice dedicated for monitoring security and a third slice for the broadcaster providing coverage of the event.

Explore More:

Billions Served: 5G Nanosatellites to Extend Global IoT Footprint

Podcast: NFV, SDN and Enabling Dynamic Satellite Ground Networks

Why the US Army Is Pursuing Software-Defined, Multi-Orbit MILSATCOM

Ready for Mainstream? Challenges of Satellite 5G