6G hasn’t been formally defined yet, and still remains somewhat of an open playground. But it’s a topic that researchers, vendors, and carriers are taking time and resources to focus on through internal efforts, organizations like ATIS’ Next G Alliance, and Europe’s Project Hexa-X.
At this point, a lot less is set in stone when it comes to 6G than is solidified. A session on Thursday will take a deep dive into the topic during the FierceWireless 5G Blitz Week, a free virtual event.
At a high level part of the vision for 6G is a deepening the connection and integration between digital, physical, and human worlds.
Kaniz Mahdi, VP of Advanced Technologies at VMware, told Fierce that if on a scale of 1-10, 5G enables interaction around a 2 or a 3, “then 6G would take it to 8 or maybe even to 10” once fully deployed.
Part of the reason that the wireless industry and others are starting discussions about 6G has to do with the typical 10-year technology cycle around new generations of 3GPP-based wireless standards. Right now, many cite 2030 as a rough timeline for 6G deployments.
Qualcomm VP of Engineering John Smee told Fierce it’s still a bit too early to set a precise date on standards or services, but generally spoke to 2030 for commercial availability.
He pointed to product development during 2029 and initial standardization around 2028, but noted it’s a loose approximation. As in earlier generations, Qualcomm is taking a long-term view to research and there’s a large role for experimentation and trials, which the chip giant is doing in its labs already.
Much of that work is going to be applicable for later 5G 3GPP releases. “At the same time, some of those ideas will be brought together, differently, into 6G,” Smee said.
Mikko Uusitalo is the head of the Research Department for Wireless Advanced Technologies at Nokia Bell Labs, and is the project lead for Europe’s flagship 6G initiative Hexa-X.
Hexa-X is also focused on 6G research to further meld the human, physical and digital worlds, having outlined six challenges to address the technical basis of 6G wireless systems.
In early March, the group released its first deliverable (PDF) for the 6G vision, including use cases and key societal values. Some examples include telepresence,robots to cobots (think interactive and cooperative robots helping at home or work for efficiency) , local trust zones (this could range from nanoscale in-body networks to wide area sensor deployments), massive twinning (Digital Twin for manufacturing, for example), and sustainable development, like E-health for all.
The beginning phases of 6G is research mainly looking at structure and framing, with openness and collaboration, according to Uusitalo. The next wave of projects will be focused on systemization, and Uusitalo pegged mid-2020, (or around 2025) as an approximate start time for 6G standardization, so before 2028. Then initial product commercialization later in the decade, or again around 2030.
VMware is part of the ATIS Next G Alliance in North America and Mahdi thinks there could be activity in the 2026-2028 timeframe – not necessarily from a radio perspective, but from human experiences and applications standpoint, driven by over-the-top innovation. Since it’s pre-standards, some would refer to this as “Beyond 5G” or other monikers.
She expects a phenomenon similar to what Apple’s app store did at the end of 3G era and resulting advances in LTE.
“If you look at it from the evolution of human experience perspective, then I do believe that something will happen in 2025 to 2028 timeframe where you will see a whole new set of human experiences evolving,” she said, particularly in the context of AR/VR.
It won’t be ”6G” by radio evolution standards, which Mahdi said doesn't happen until Terahertz is defined and able to be deployed.
“I don’t think we’ll want to wait until Terahertz is deployed to fully start consuming those [human experience] technologies on top of 5G wireless systems,” Mahdi said.
Is it all about Terhertz?
When it comes to spectrum for 6G, some are looking at super-high frequencies above 90 GHz (sub-THz 100-300 GHz) and up higher from 300 GHz up to 3 THz.
Right now, the highest frequency bands in use for commercial mobile are millimeter wave, including up to 39 GHz in the U.S.
Terahertz promises massive capacity, but if mmWave gets a bad rap for signal propagation, THz would be much more difficult to use for mobile broadband coverage.
That’s why researchers like Uusitalo think Terahertz can be useful for high-capacity applications that intertwine the three realms of physical, digital and human.
For example, the telepresence use case – where a human, group of humans, machines or group of machines are all interacting with each other, independent of physical location, and with objects that might not physically be located anywhere at all – or a combination of these.
“If you have this kind of interaction, it is driving the need for capacity,” Uusitalo said. It’s also about massive amounts of data expected to help fuel interactions in a 6G world, like connecting information from a smart city or large campus and complex.
All of these are data intensive and in need of capacity, Uusitalo said. “So yes, these higher frequencies could help with that.”
But Uusitalo and Qualcomm’s Smee both point out that lower bands and currently used spectrum are part of the 6G picture.
“At the same time, it’s also very important to look at what could be down at lower frequencies,” Uusitalo, including below 6 GHz, the mmWave bands, or newly available spectrum.
Just like 5G has multiple spectrum bands in use (in the U.S. that ranges from 600 MHz to mid-band up to mmWave frequencies, to name a few), Smee said 6G will also be designed for those bands and not just a single band or range.
“We’ve seen historically that ability to look end-to-end to new designs and new approaches that enables us to not only bring the new G into new bands” but also use existing bands thanks to new technologies, Smee said. “Terahertz is absolutely important and we’re working incredibly hard on it, but at the same time that’s just part of 6G.”
A key theme that arose is how data-driven a 6G world is expected to be, with artificial intelligence and machine learning (AI/ML) helping foster the “connecting of intelligence.”
So think of devices, sensors, robotics, collecting information from humans, physical inputs, machines, groups of all of the above and then that information being shared between and amongst in a new kind of experience.
That leads to a key research focus for both Nokia and Hexa-X, which is the concept of a “networks of networks.” Where for example, groups of humans or machines are utilizing dedicated networks with massive amounts of data, in hierarchies of networks to serve different needs, Uusitalo explained.
“And then how do we tie all of these networks together to this ‘network of networks,” he said, speaking about one major research focus.
Machine learning is already happening in 5G on devices and in the network, Smee noted.
“But at the same time in 6G we’ll be designing more foundationally for data-driven end-to-end systems,” he said.
Evolution from 5G
Like earlier technology generations, 6G doesn’t mean 5G just falls away. As operators are investing heavily to deploy 5G networks (as seen when U.S. carriers spent more than $81 billion for C-band spectrum), there is a clear question of how to leverage and build while looking toward the future.
Technology trends seen with 5G, like a disaggregated RAN architecture and virtualized networks, for example, are setting the stage already by enabling things like specialized deployments, according to Smee. But it will be incorporated into 6G systems at a foundational level.
Qualcomm views scalable network architecture and enabling 6G functionality in a cost-effective way as one important area for long-term research. It brings up questions like how the wireless ecosystem is able to leverage investments as network architecture evolves and transitions to 6G.
The conversation within VMware also isn’t about how to drop 5G, but how to move existing assets further down the path of evolution, according to Mahdi.
“How do I evolve them so I make the 5G experience better and I evolve 5G to a point where I’m making my systems ready for 6G,” she said.
And VMware is looking to shape its path toward 6G by exploring how to fulfill the ambition of 5G real-time collaboration and interaction among smart things.
A critical element that’s missing is the edge, she said.
“The notion of the edge is basically not well defined,” Mahdi said, and where energy is focused on the future transition of 5G to 6G.
Advances in the radio, programmability with open interfaces and disaggregation, and cloud-native evolution of network functions are three fundamental technologies that have progressed extremely fast in 5G. Areas that still need to mature, according to Mahdi, deal with the intersection of wireless, cloud, robotics and automation.
“Hopefully by the time we are able to comfortably and confidently say that yes I have delivered the 5G promise… by then spatial computing and the evolution around the edge and the extension of the edge all the way to the user device, all of those, and especially also advances in robotics, they will be squarely in place to shape the new landscape for 6G,” Mahdi said.