While the FCC mulls changes mostly to the licensed portion of the 3.5 GHz Citizens Broadband Radio Services (CBRS) band, some operators are looking to use the General Authorized Access (GAA) unlicensed portion of the band, which is expected to be made available before the Priority Access Licenses (PALs) that are of so much interest to wireless operators.
But AT&T is going to wait to see the final rules for the licensed portion before it reveals much about its plans for GAA, according to Gordon Mansfield, vice president of RAN & Device Design at AT&T. The operator needs to see the rules of the licensed component before deciding on the GAA portion, he told FierceWirelessTech on the sidelines of Mobile World Congress 2018 in Barcelona. It’s a position similar to one expressed last fall, when Mansfield said the operator would take a wait-and-see approach to the band while issues remained outstanding.
As for the general structure of CBRS as a shared band, “we’re absolutely supportive of that,” he said, adding that it’s hard to talk about what AT&T would do with the GAA spectrum without knowing how things are going to shake out for licensed. One of the values that AT&T brings to the table as a licensed operator is the licensed perspective.
FCC Commissioner Michael O'Rielly said during AT&T's public forum on 3.5 GHz last month that the real point of contention appears to be around the appropriate geographic license area size for auctioning PALs. He was encouraged by reports suggesting that the parties involved with the CBRS band are moving away from their previous positions and starting to talk to one another about possible compromises. The FCC is expected to make a decision on 3.5 GHz CBRS band within the first half of this year.
Next door to the 3.5 GHz band is the 3.7-4.2 GHz band, which is also being targeted for 5G and proposals are under consideration by the satellite industry to make some of its C-band spectrum available. Generally speaking, mid-band spectrum allows for some compelling uses when it comes to mobile terrestrial.
“We’re very interested in seeing the commission identifying ranges of spectrum like that that can be put to use,” Mansfield said, noting that there’s no “clean” spectrum anywhere and that’s the challenge—incumbents end up having to be removed or moved.
Not all bands share the same kind of set-up as 3.5 GHz so applying the same type of sharing model won't always work. It largely depends on who the incumbents are and how the spectrum is being used on a geographic basis. In the case of 3.5 GHz, the incumbents are very isolated in specific areas and being able to use the spectrum for other purposes makes sense, Mansfield said. That’s not always going to be the case with other bands. If someone is already using the spectrum on a broad geographic basis, it could be difficult—you have to ask now much spectrum is left to be shared.
Wireless operators increasingly are combining unlicensed spectrum with licensed. Steve B. Sharkey, vice president, Government Affairs, Technology and Engineering Policy at T-Mobile, said during a FierceWireless event at MWC last week that if the GAA use moves forward this year, T-Mobile will be in a good position to start using the band under GAA. Then as the licenses are issued, it will be able to take advantage of that. He indicated that the early CBRS rollouts are likely to look a lot like LAA.