IT leaders should prepare now for future 6G networks, according to a panel of experts – despite the patchy rollout of 5G to date and the ongoing struggle to monetize that technology.
So, what might the next generation offer that 5G cannot, beyond a higher-frequency communications channel?
Analyst Prakash Sangam is on the board of directors of the Wireless Communications Alliance, which hosted the US event on 16 February. Chairing the discussion, he acknowledged 5G’s existing commercial challenges and said:
Monetization is still a challenge for operators. There are a few new revenue streams in terms of fixed wireless access, unlimited offerings, and so on. But they're still looking at ways of monetizing all their investments. The grand promise of 5G, such as a massive IoT rollout for industry, has yet to be fulfilled.
So, is it too early to look ahead to next-generation wireless? Not according to Dan Warren, Director of Advanced Network Research at Samsung R&D UK. He said:
We've launched a 6G research team, so are in the early stages of thinking about what 6G delivers above and beyond 5G advances. The team is not focusing so much on a new radio interface, or high-frequency spectrum bands. We're looking more at an end-to-end system architecture. With the exception of ‘software-ization’, that hasn't been disrupted for quite some time.
The software-ization of the end-to-end architecture has been an ongoing trend as the performance metrics of a software-based implementation come up to the levels that are required for a fully software-ized core and radio. But now that we've got there, the next question for us to answer is: is the network that we've designed as optimized as it can be? And is it as optimizable as it can be?
The second stream of research that we're conducting is around how to implement AI within that architecture. In a way that is pragmatic, which allows AI applications to interact with each other and sort out any conflicts.
And then be able to deliver more with less resource, and focus on some of the key value indicators that are coming through in the 6G requirements-setting stage.
Ben Coffin is both a wireless engineering graduate and Solutions Marketing Manager for Advanced Wireless at testing and measurement specialist Keysight Technologies. He talked up the societal benefits of faster, higher-bandwidth communications, as well as the technical ones:
We see 6G as a unification of a lot of moving pieces inside of the ecosystem. It's a connection of not only the physical and digital worlds, but also the human one. Whether that's sustainability, or just the connectivity vertical and what that access means to people.
Traditionally what you would expect is, hey, we're talking about new spectrum that would be available in 6G prototyping in something like the sub-terahertz band. And that is absolutely something we have on our radar. But we see 6G as a lot more than that, as figuring out how to integrate AI and use optimization throughout the network. And that being native functionality.
The other thing I'll throw into the mix is we see technologies like digital twins becoming a really necessary part of the workflow.
For spectrum consultant Michael Marcus, however, 6G will primarily be a technical challenge – and opportunity. He said:
6G will probably get access to spectrum above 100 gigahertz, which it will need to get the lightning-fast speeds that are going to be needed. But realistically, that will probably mean using that spectrum first for backhaul before it uses it for uplink and downlink, because the need for uplinks and downlinks faster than 5G is still somewhat speculative.
Yet high-frequency communications carry challenges of their own, he added:
Most telecoms use of spectrum is horizontal or near horizontal, and at frequencies above 100 gigahertz, atmospheric attenuation is important. And any path that reaches a satellite has huge attenuation before it gets there.
So, a key issue of 6G planning will be: can we figure out a way to share 6G spectrum with passive uses on a non-interference basis? Fortunately, at WRC [World Radiocommunication Conferences] 2000, the US proposed a framework for that, which is now known as WRC Resolution 731. It has safeguards to protect the passive users, but makes clear that sharing was the intent.
But unfortunately, certain federal agencies whose names won't be mentioned here apparently opposed that US position in the year 2000, and still oppose it and like to pretend it never existed. So, there is a problem, both a technical one and a policy one to be resolved.
Part evolution, part revolution
The challenge of 6G signal attenuation over long distances has also been a focus for technology consultancy IDTechEx this month. The company has produced a report saying:
While transmission loss and atmospheric dispersion is bad enough at high-frequency 5G bands, affecting the range and signal integrity of mmWave 5G networks, it will be even worse at 6G bands like the D-band (110-170GHz).
Thus, the world’s first consortium for 6G technology development, 6Genesis Flagship Program 2018, identified the development of new low-loss materials as a critical technology enabler for 6G.
Therefore, it is important to investigate the potential dielectric performance required for 6G technologies, which is spurring current research into ultra-low-loss materials for 6G by many important players.
But for many IT strategists, ‘big picture’ issues dominate. In order to thrive in the years ahead, 6G networks will need to be more sustainable, secure, energy-efficient, and trustworthy.
Dr Ian C Wong, Director of RF and Wireless at US-based network testing and assurance provider Viavi Solutions, said:
What I would like 6G to be goes back to our thinking about being good stewards of our natural resources in terms of sustainability. Being energy-efficient enough that we can provide good, ubiquitous services.
It behoves us as an industry to think about not just the next great, shiny object, but really consider how to provide services that are truly critical. At lower cost in terms of energy, and in dollars.
I think we will have new spectrum. I think we will do a much better job of utilizing that spectrum, providing services that are critical for our societies. It's going to be an evolution for the most part, right? And we as an industry have matured through five generations of doing a really good job of providing connectivity to the masses.
But on the other hand, I think there will be potential for revolution in certain areas. Things like machine learning, using that technology as a way to truly automate the network.
Again, that goes back to being really good stewards of our resources, lowering the cost, and using automation to do that.
A useful high-level discussion that helps us look ahead. But first we need to maximize 5G’s potential.