AT&T Building Islands of LTE in 2011
AT&T revealed on Wednesday that Atlanta, Chicago, Dallas, Houston and San Antonio will get LTE this summer and said the 4G technology will be in 15 markets by year's end. (See AT&T Starts Small With LTE .)
What the operator didn't reveal was any kind of 4G roaming deal with major rival Verizon Wireless , which started its deployment with 38 cities and is adding over a dozen markets in June with plans to cover more than 185 million potential subscribers in 175 markets by the end of 2011. (See AT&T Starts Small With LTE and Verizon Speeds Up LTE Expansion .)
"It’s too soon to talk about that -- we haven’t announced any details there," said AT&T spokeswoman Mari Melguizo in an email reply to questions.
Verizon had a similar story in answer to the roaming question: "First things first," says Verizon spokesman Jeffrey Nelson. "Let me know when they actually launch LTE rather than just talk about it. They’re already more than a year behind us."
Without an LTE roaming deal in place with Verizon, early AT&T LTE users will fall to 21Mbit/s HSPA+, which AT&T also markets as "4G" in some areas and slower 3G in others. AT&T's coverage map says that the HSPA+ technology has been applied to "virtually 100%" of its "mobile broadband network" but scrolling over the map shows that this doesn't mean nationwide coverage by any means.
It is certainly technically feasible to build a device that can roam between class 17 -- AT&T's C- and B-band 700MHZ LTE frequencies -- and Verizon's C-Band 700MHz block ("class 13" to its friends). "[It] just means that the device has to have two RF front ends for bands 13 and 17," says Eran Eshed, co-founder and VP of marketing and business development at LTE chip developer Altair Semiconductor .
"If AT&T will continue to run voice service over their own 3G network and roam to [Verizon] only for LTE data, than things will be simpler," he adds. "In any case, they will probably have to have some level of integration between the core networks."
Early evidence suggests that, however, AT&T's LTE devices aren't built to support roaming onto Verizon's band 13. Back in October 2010, AT&T spokeswoman Jenny Bridges confirmed to Fierce Wireless that the LG Electronics Inc. (London: LGLD; Korea: 6657.KS) USBConnect Adrenaline HSPA+ dongle, which is upgradeable to LTE, isn't built to roam onto Verizon's side of 700MHz band.
AT&T Melguizo had "no further comment" on that issue. "I do want to point out that since we don’t have the LTE upgrade in place for that device at this time, it’s irrelevant either way," she added.
— Dan Jones, Site Editor, Light Reading Mobile