AT&T promises to make its LTE phones interoperable with the small carriers

AT&T has given in to the growing pressure from the small operators and the Federal Communications Commission to support interoperability on LTE devices. That means that in the future the same phones and gadgets that work on AT&T’s LTE networks will work on the networks of dozens of regional and rural carriers launching LTE in 700 MHz band.

In a post on Ma Bell’s policy blog, AT&T federal regulatory VP Joan Marsh said that AT&T has reached a consensus with the FCC and other carriers to support Band 12 devices, which covers both the 700 MHz spectrum owned by small carriers and the neighboring airwaves AT&T uses its growing nationwide LTE network.

Marsh didn’t give a specific time frame for when it would achieve full interoperability, and to be honest it might take some time before the same smartphones will be able to cross network boundaries. AT&T spent a lot of effort over the years creating its own boutique band in 700 MHz (Band 17), and device makers tailored their phones for its network. For instance the iPhone 5s and 5c announced today will work on AT&T’s networks but not on U.S. Cellular’s(s usm) or C Spire’s, even though they’re supposedly sharing the same band.

In a statement, acting FCC chairwoman Mignon Clyburn lauded the hard-fought compromise:

“America’s mobile consumers have a reason to celebrate today: After many frustrating years, wireless carriers have finally reached a voluntary industry solution that will resolve the lack of interoperability in the lower 700 MHz band in the most efficient manner. This is a big win for consumers, especially in rural areas, who will see more competition and more choices. Also, by making it easier for small wireless carriers to compete, today’s interoperability solution will spur private investment, job creation, and the development of innovative new services and devices.”

So it’s good news for small carriers, but this certainly isn’t the end of the massive LTE fragmentation issue in the U.S. — operators are still all over the spectrum map in their LTE deployments. It’s not even the end of fragmentation in 700 MHz. Verizon Wireless(s vz)(s vod) is still sitting pretty on its own boutique slice of 700 MHz, Band 13, and it shows no signs of budging.

AT&T made its concessions the same day it invested more heavily in the 700 MHz airwaves. On Tuesday it closed its acquisition of a big chunk of the licenses Verizon agreed to divest when it landed the cable operators’ 4G spectrum haul last year.