Why AT&T expects a big boost to its 5G coverage

AT&T is adding more resources to its budding 5G network. The wireless giant said on Friday that it has started deploying a new network technology known as dynamic spectrum sharing that could eventually lead to a big jump in coverage. 

The carrier has turned on a 5G network for 120 million people using low-band spectrum, with a goal to have a nationwide network this summer. But the new technology will allow it to use its spectrum holdings for its existing 4G LTE service (what AT&T calls “5GE”) to power its 5G network without disruption. 

Read more: 5G glossary, from spectrum to small cell to MIMO

This technique, which other carriers like Verizon Wireless have touted, is key to getting faster 5G, the next-generation wireless technology poised to change how we live our lives, to more people. Despite the promise of 5G, the early launches have seen either slim coverage or speeds that are only marginally better than 4G. 

AT&T, however, is not providing many details at the start of the new deployment, with Igal Elbaz, AT&T’s senior vice president of wireless technologies, stressing that it is “day one.” 

Elbaz says the first deployment is live in “North Texas,” though he wouldn’t say exactly where, and available on the LG V60 ThinQ 5G, Samsung Galaxy Note 10 Plus 5G and Samsung Galaxy S20 line of 5G phones through an already deployed software update. 

Other devices should be added in the future with Elbaz simply saying that “more devices will follow soon.”

AT&T uses its 850MHz spectrum for its low-band 5G network, which offers broad coverage but speeds comparable to 4G, and higher frequency millimeter-wave bands for its high-speed but limited-coverage 5G Plus offering. Elbaz wouldn’t say which spectrum bands the carrier is using at the DSS launch. 

He similarly is not making promises for speed improvements, equating 5G today with some of “the higher speeds of LTE.” 

“As we move forward and as the technology evolves,” Elbaz continues, “you’re going to see improvement in speed.”

A small step today for a bigger leap later

Although it isn’t life-changing right now, DSS is important for AT&T as well as Verizon as they look to expand 5G. 

Unlike T-Mobile, which just acquired a large swath of midband 2.5GHz spectrum as part of its merger with Sprint, AT&T and Verizon don’t have the same amount of unused spectrum, or wireless airwaves, available to deploy for 5G. 

The Sprint spectrum T-Mobile acquired was largely untapped relative to Sprint’s 4G LTE network, allowing T-Mobile to already begin putting it to use without the risk of impacting those on 4G. 

While AT&T and Verizon have a lot of spectrum, much of it is tied up to provide service to the large majority of customers who have 4G LTE devices. The need for spectrum is one of the reasons both carriers are expected to be active bidders in an upcoming Federal Communications Commission auction in December for newly freed up midband spectrum known as “C-Band.”

In the past, if a carrier wanted to upgrade its network technology it would have to shut down and “refarm,” or redeploy, the existing network which takes time. With DSS, the carriers can begin sharing that spectrum between 4G and 5G devices without pulling it completely away from either side.

The 4G users still can use it as they were before while 5G devices gain a boost with networks that have better coverage and faster speeds. The “dynamic” nature of the technology allows AT&T to continue to make those adjustments area by area depending on the 4G and 5G needs of a market and as people begin to upgrade 4G devices to 5G-capable ones. 

“It is a critical technology for everyone, not just for us, to scale it over time,” says Elbaz. “That DSS technology allows us, and others, by the way, to be much more efficient in that transition and without affecting customers that are still on LTE.”