AT&T Does Not Use CBRS in Mobile Network; Verizon Does

Mobile operators (though not all) and cable operators (the biggest) were big winners of Citizens Broadband Radio Service 3.5 GHz mid-band spectrum in recent U.S. spectrum auctions. How that spectrum will be used might vary, however. 

source: futurithmic

AT&T does not actually use Citizens Broadband Radio Service (3.5 GHz) in its core mobile network. 

“The way we use CBRS today is mainly in part of our fixed wireless in rural America, as part of our CAF-II program,” says Igal Elbaz, AT&T SVP. But we didn't build CBRS on our standard macro,” he says.

AT&T also uses CBRS for private networks, though. 

Verizon, which has been capacity challenged, compared to T-Mobile and AT&T, does use CBRS in its core mobile network. Prior to the CBRS auction, Verizon had roughly the same amount of low-band and mid-band spectrum as did upstart Dish Network. 

source: Wells Fargo, LightReading 

It is not yet completely clear how Comcast will deploy CBRS. In principle, Comcast, Charter Communications or Cox Communications could use CBRS to construct local radio access networks of their own. They might federate their assets to create a larger footprint, as they did with their Wi-Fi services. 

What is unclear is whether fixed wireless services will be an early use case, as Charter seems to suggest will happen, or whether CBRS winds up being more useful as a way of shifting mobile traffic onto its own network, and off the wholesale Verizon network. That obviously would provide cost savings for the cable operators. 

Of course, longer term, CBRS might well wind up used in a variety of ways: supporting private networks, fixed wireless and in the core mobile network. As always, use cases will match the particular requirements for each operator. Verizon needs lots more mid-band spectrum, so its use in the core network makes sense.

AT&T has less need for using CBRS in its mobile network, in part because it is expected to bid extensively in the C-band auctions of mid-band spectrum as an alternative to adding CBRS spectrum. 

T-Mobile has such extensive mid-band capacity holdings that it is not expected to be active in acquiring additional mid-band assets.