AT&T, Nokia make 5G call over C-band in field tests

AT&T is gearing up to deploy C-band spectrum for 5G later this year, and recently completed the first call on its network with Nokia using commercial gear.

In March, the carrier secured 40 MHz of the first available batch of C-band spectrum, to be cleared later this year, with 80 MHz on average overall as the second-biggest spender at Auction 107. It recently upped coverage targets, now planning to reach more than 200 million people with C-band by the end of 2023.

The successful field test took place in early May in Detroit, Michigan. It used the Nokia AirScale baseband and 5G massive MIMO 64T64R C-band radio, along with a smartphone form factor mobile test device with Qualcomm’s Snapdragon X55 5G Modem-RF system.

Even before the record C-band auction concluded, AT&T was making plans for how to test the key mid-band frequencies. That included the team in Detroit, as well as Plano, Texas, (Dallas is home to AT&T HQ) which scoured sites, planned equipment upgrades and worked with tower and radio vendors and getting spectrum cleared in preparation. Field tests came after lab trials to work out any issues, using a Mobile Test Platform.

RELATD: AT&T digs into C-band with multiple trials

“Plano is in AT&T’s backyard, so we knew we wanted to secure spectrum here to test,” Paritosh Rai, head of AT&T’s 5G Project Management Office, in a Thursday blog. “And in the case of Detroit, it was a good location to test coverage that would benefit large business customers.”

The carrier said that work allowed to it move fast and achieve field test calls over C-band just weeks after the FCC auction concluded.

“Being the first to make a call on mmWave was an important event in 5G development in 2018,” said Rai. “Bringing 5G innovation to market is very important to our teams. Working on these C-band field test calls gave us a feeling of, ‘Let’s make history again!’”

RELATED: Nokia ready with C-band gear on heels of 5G spectrum auction

The Plano team actually completed their test call first, on April 22 – but the one using commercial Nokia gear happened shortly after in Detroit on May 2.  

“The speed and agility of these trials were amazing,” said Tony Seyfried, AT&T Tech Vendor Manager who led the Detroit team, in the blog. “These tests will allow our teams across the country to test and implement the C-band even faster now, which means our customers will be able to utilize this spectrum sooner."

Fierce reported in May that AT&T applied for license modifications in California, Michigan and Texas, for C-band trials using both Nokia and Ericsson equipment.

For the successful call, AT&T used one of Nokia’s new mMIMO antennas built to operate in the n77 (3.7-3.98 GHz) allocated for C-band in the U.S., alongside the vendor’s latest 5G software. Nokia has a five-year deal to supply C-band equipment for the roll out and prepped gear to support the new frequencies as soon as they became available.

RELATED: Nokia adds C-band support in new 5G small cell lineup

Back in June 2020, the vendor was testing its commercial 5G AirScale portfolio in Dallas on 3.75 GHz spectrum, reaching speeds of more than 1 Gbps.

Kevin Hetrick, VP of Construction & Engineering at AT&T, in a statement pointed to added capacity and coverage afforded by rolling out mid-band spectrum.

“In fact, we’ve committed to covering more people with C-band by the end of 2023 than any other carrier,” Hetrick stated. “Our planned C-Band launch with Nokia will add 5G capacity and coverage where it’s needed. Nokia’s C-Band portfolio has the capabilities and performance to enable AT&T to deliver an exciting and powerful 5G experience that our subscribers have come to expect from us.”

Competitor Verizon aims to cover more people with C-band sooner – 100 million by the first quarter of 2022, but less than AT&T by the end of following year with a target of 175 million people (increasing to 250 million after 2024).  

Verizon itself has been testing out C-band across multiple locations, and in April had already begun installing equipment from Ericsson and Samsung. T-Mobile, meanwhile, also secured C-band and has been focused on 2.5 GHz. It expects to cover 200 million people with mid-band spectrum by the end of this year.