AT&T wants to test 24GHz millimeter wave equipment -- as the FCC gets ready to fire up its first 24GHz 5G auction on March 14 -- as well as further "sub6" equipment testing in Texas.

AT&T applied for a two-year "5G" experimental license to cover testing in the 5GHz and 24GHz bands in Austin, Texas, on February 20. The application is still listed as "pending" at the FCC.

"AT&T seeks to further validate system design and operation in the sub-6GHz and 24 GHz+ mmWave bands for certain applications and use cases, such as IAB (Integrated Access and Backhaul), LNC (LTE-NR Coexistence), V2X (Vehicle to vehicle/others), URLLC (Ultra-Reliable Low Latency Communication), mMTC (massive Machine Type Communications), and eMBB (enhanced Mobile BroadBand)," the operator said in its documentation to the FCC.

The operator will be testing up to ten prototype devices (user equipment) within a 5km range of a basestation in Austin. AT&T has not named its prototype equipment suppliers for the tests yet.

The 24GHz test indicates that Ma Bell is potentially gearing up for the 24GHz spectrum auction. AT&T so far has used 39GHz spectrum for its existing "5G+" millimeter wave service.(See AT&T Adds 2 More US Cities to 5G Plans in 2019.)

AT&T, as well as Verizon and T-Mobile, were among the qualified bidders for the previous 28GHz 5G auction, which ended on January 24. The FCC isn't revealing the the winners of that auction yet, until the 24GHz auction is closed. (See Cox, Frontier Won't Bid in 24GHz 5G Auction .)

Meanwhile, the proposed 5GHz test gives more clues to what frequencies AT&T may use when it offers its "nationwide" low-band 5G service in the US in 2020. (See AT&T Low-Band 5G to Arrive With Samsung Phone in 2H19.)

AT&T says that its lower-band 5G support will begin to arrive in the second half of 2019, going nationwide in 2020. AT&T hasn't yet said which "sub6" frequencies it will use for the service.

We've asked AT&T about the test plans; they haven't responded as yet.

— Dan Jones, Mobile Editor, Light Reading