AT&T has remained relatively quiet about efforts to upgrade its 5G network with speedy midband spectrum. But the company's silence belies plenty of progress, according to a new OpenSignal report released Wednesday.

According to the network-monitoring company's latest findings, roughly a third of all AT&T's 5G transmissions traveled over its new C-band spectrum holdings during the month of September. That figure is up from just 4.6% in March.

Perhaps more importantly, AT&T's 5G download speeds have increased as a result of its C-band deployment.

"Our AT&T users' average 5G download speeds have steadily increased since the beginning of the year when the operator started to roll out 5G services in the C-band," OpenSignal wrote in its report. "They enjoyed a rise of 17.3 Mbit/s in their average 5G download speeds between March 2022 and September 2022. This means average 5G download speeds increased by 34.6% in this period."

AT&T still trails Verizon in terms of overall C-band buildout and 5G download speeds, but the gap between the two companies isn't huge. OpenSignal reported that almost 50% of all Verizon's 5G connections in September occurred over its C-band spectrum, compared with around 30% for AT&T.

"AT&T has made significant progress in rolling out its 5G services in the midband," OpenSignal said.

Figure 1: Nearly a third of AT&T's 5G connections were over its C-band spectrum in September, according to OpenSignal. Click here for a larger version of this image.
(Source: OpenSignal. Used with permission.)

The findings are noteworthy, considering AT&T stumbled out of the midband starting blocks. Company officials said last year that AT&T would not meet its goal of covering 70 million to 75 million people with C-band connections by the end of 2022, blaming supply chain issues. And at the beginning of 2022, AT&T launched C-band services across "limited parts" of just eight US cities.

Verizon, meanwhile, kicked off 2022 by launching C-band 5G services covering 100 million people.

By the end of 2022, Verizon hopes to cover around 175 million people with its midband 5G network, while AT&T hopes to cover around 100 million with its midband network by that time.

AT&T spent a total of $36 billion across two recent FCC spectrum auctions to acquire midband spectrum licenses. That spectrum clearly represents a massive upgrade to the lowband 5G network that AT&T has been using to cover much of the country with 5G.

According to OpenSignal, 5G download speeds on AT&T's C-band network averaged around 113 Mbit/s. That figure dropped to 37 Mbit/s on AT&T's lowband AWS spectrum, and just 33 Mbit/s on its lowband 1900MHz spectrum.

"C-band explains the jump in users' overall 5G download speed on both carriers [AT&T and Verizon] because of its significantly greater capacity than lower frequency 5G bands," OpenSignal wrote.

Figure 2: (Source: dpa picture alliance/Alamy Stock Photo)

AT&T is spending roughly $5 billion this year to install midband 5G radios atop its cell towers all over the US. The company is primarily using equipment from Ericsson and Nokia for the buildout. The company said it expects to spend another $5 billion next year to continue expanding the reach of its midband 5G network.

As that work progresses, it's likely that AT&T's 5G speeds will continue to rise in OpenSignal's rankings.

However, OpenSignal pointed out that both AT&T and Verizon trail T-Mobile in the deployment of midband spectrum for 5G. The firm reported that almost 70% of T-Mobile's 5G transmissions traveled over its midband spectrum in September.

Related posts:

— Mike Dano, Editorial Director, 5G & Mobile Strategies, Light Reading | @mikeddano