Carriers Have Little Urgency for Moving From 5G to 6G: Vodafone

Vodafone and other wireless carriers have a ways to go to deploy 5G and are in no hurry to get to 6G, David Lister, Vodafone 6G research lead, said Monday during a 6G workshop streamed at the Technology & Innovation Centre at the University of Strathclyde in Glasgow, Scotland.

“We’re in no rush for 6G -- we’re still rolling out 5G; we’re still at the early stages,” Lister said. The “journey” to 6G will see technological advances in AI and quantum computing and different “delivery mechanisms” including fixed wireless, Wi-Fi and satellite communications, he said. “We’re not going wake up one day and go, ‘Hey, this is the 6G world,’” Lister said.

The 3rd Generation Partnership Project, which oversees mobile standards, has yet to formally start 6G studies and won’t for another year, Lister said. 3GPP plans to finish work on the specifications for 6G in 2029, he said. “We’ll see in a couple more years where that takes us,” he said. Lester questioned whether in a world where software is becoming more important than hardware, the 10-year cycle for wireless generations makes sense.

Lister also questioned whether each new wireless generation should get access to new bands. “There’s a limited amount of spectrum available to mobile operators,” he said. There should be more focus on what spectrum is needed to meet future traffic demands in networks and making sure it’s available in the right quantity at the right time, he said.

We always hear that spectrum is a finite and “scarce resource,” said David Willis, group director-spectrum at the U.K.’s Office of Communications. “There are a few levers we can pull” through sharing, power levels and geographic separation “to increase the supply,” he said.

Regulators have to track the trends, Willis said. Mobile broadband is continuing to grow, traffic continues to expand, driven by fixed wireless access (FWA), he said. Ofcom is seeing a slowing in annual growth rates to below 20% and as low as 10%, he said. “You’re still seeing growth but not the dramatic, exponential growth you might have seen at one point,” Willis said. In the U.K., the most growth is concentrated in a few markets that cover a small percentage of the country, he said.

Ofcom is looking at more “niche solutions” to meet growing demand, Willis said. The agency is examining how to enable private 5G networks and neutral hosts, whether there should be “differentiated” policy for FWA and for a new generation of Wi-Fi, he said. “You’re really looking at adding capacity layers -- dense urban spaces, outdoor coverage, indoor coverage, deep rural capacity in market towns and various industrial spaces like ports and warehouses,” he said.

Standard solutions for sharing spectrum are critical, Willis said. If every band has a unique approach, “it will take us forever to implement it,” he said. Willis noted the amount of time it has taken to develop gear for the TV white spaces and citizens broadband radio service bands.

Monisha Ghosh, engineering professor at the University of Notre Dame and former FCC chief technologist, noted that 80% of data on the networks either originates or terminates indoors, but the cellular network was built before Wi-Fi became commonplace. Ghosh said when she went indoors at the conference she checked the difference on her devices between Wi-Fi and the carrier network. The Wi-Fi connection was 200 Mbps, the network connection “barely 6,” she said.

Carriers continue to build networks based on the premise they’re going to serve indoor customers, Ghosh said: “Asking for more and more power and more and bandwidth to serve the increasing needs … indoors to me is not the greatest use of spectrum.” It’s also not very energy efficient, she said. Understanding how needs have changed and “allocating spectrum appropriately” is “very important,” she said.

Except in the U.S., millimeter-wave spectrum isn’t being widely used, said Edward Tiedemann, senior vice president-engineering at Qualcomm Technologies. Other than point-to-point connections, deployment is “a bit premature,” he said. We need sophisticated antenna systems, at lower costs, to make high-band more usable, he said.

Tiedemann said the 7.125-8.4 GHz band is being looked at in some form throughout the world, and is set for study under the U.S. national spectrum strategy. It includes military systems worldwide, including NATO systems, he said. “This is where we’re going to have some real challenges to try to understand sharing,” he said. We don’t know what the waveforms are in parts of the 7/8 GHz because of secrecy for government systems, he said.

Ghosh agreed on the problems presented by the 7/8 GHz band. Almost any band can be used indoors without interfering with government incumbents, which isn’t true of outdoor connections, she said. “We should try to figure this out better -- we have not done a good job of trying to understand devices, needs when they’re indoors … and trying to leverage that into spectrum policy,” she said.

Unlicensed spectrum can be used the quickest, followed by exclusive-licensed use, Ghosh said. Database-based sharing takes the longest, she said. As we look at how to share a band, policymakers should ask how long it will take for new uses to start, she said. If it takes 10 years, “the use cases [will] have moved on,” she said.