Accenture and CTIA identified three blocks of lower midband spectrum that they believe to have ‘the greatest potential for 5G expansion’
Often called the goldilocks of spectrum, 5G midband spectrum delivers better coverage than high-band and higher speeds than low-band. It is widely accepted that the United States has been comparatively slow in freeing up midband spectrum for use by service providers, and that even with C-band and CBRS deployments underway, more is still needed. Tejas Rao, managing director at Accenture, gave RCR Wireless News deeper insight into why exactly that might be, and why 5G marks a shift how network roll out progress should be evaluated.
“We have to re-farm [more midband] spectrum to make it available for 5G,” Rao told RCR Wireless News. “We’ve had the C-band auctions and CBRS [but] there is still room in midband that we think we should unlock. We’ve got coverage, we’ve got speed, but as the data grows, the capacity will be filled by the midband.”
In a recent report, Accenture and CTIA examined spectrum allocation in the United States and found that the country’s wireless industry currently has access to 5% of lower midband spectrum. Unlicensed spectrum users and government users, however, have access to 7x and 12x that amount, respectively. The pair identified three blocks of lower-midband spectrum — the lower 3 GHz band (3.1-3.45 GHz), the 400 megahertz in the 4.4-4.94 GHz band and the 400 megahertz in the 7.125 and 8.4 GHz band — that are believed to have “the greatest potential for 5G expansion” and should therefore be opened up and allocated for cellular use.
“Allocating these three bands for commercial wireless use would result in unlicensed users having access to 1.19X and government users having access to 1.34X the amount of spectrum as commercial wireless users,” said CTIA.
When preparations for 5G rollouts began, the U.S. at large was very focused on allocating low band to address coverage and then high band for speed and capacity, midband was put on the back burner. However, when T-Mobile US acquired Sprint, it also got more than 100 megahertz of the latter’s 2.5 GHz midband spectrum, and for the former, that was a big deal.
“This midband buildout, this is the game,” CEO Mike Sievert said back in 2020. “And we are way ahead of anybody in this area. We plan to stay ahead.”
In fact, according to Rao, it is T-Mobile US’ 5G lead, driven by its early access to all three bands, that inspired the spectrum report in the first place.
“You just need all three,” Rao said simply, adding that 5G represents a notable departure in how networks are built, what they’re used for and how to assess their success. Traditionally, he explained, when we talk about network builds, it’s in terms of how much of the population is covered. But with 5G, you don’t have to build the same network in every location, so that metric begins to change.
“Because you’re either building it for low latency or because you have IoT sensors, like in smart city application, or you want to close the digital divide,” he continued. “You now have the opportunity to take your spectrum assets and point them very directionally in areas where you want to unlock those types of applications.”
But, he pointed out, to tap into this unprecedented level of flexibility, a carrier needs sufficient access to all areas of the band.
“Carriers talk about their network in terms of POPs covered. That’s been the traditional deployment model because it’s been so focused on making sure you have pure coverage. But this is the first time you have now this new flexibility,” said Rao, highlighting features unique to 5G that make this possible, such a virtualized core and edge networks. “Once I’m virtualized, I look like a cloud,” he explained. “What I get from cloud is the ability to be agile, to spin up compute and storage when I see more traffic. I don’t have to configure it today, but I have the elasticity of cloud.”
Historically, mobile networks have always been designed to handle the carrier’s highest traffic, so they deploy a ton of hardware for peak loads, which may not be necessary the majority of the time.
“We fundamentally believe that this generation of 5G is game changing in a way that most of the other technologies weren’t. They were incremental. 2G was about ripping the cord off the landlines; 3G was about enabling the internet; 4G is about video. With 5G, you get this unlocking of everything that you wanted to do,” said Rao.
