AT&T just made a great leap forward. With its first five LTE cities, the big blue wireless carrier is setting up its data network for the next decade. So I sent a bunch of questions to AT&T, hoping to get details on whether it would allow LTE roaming with Verizon, when LTE phones were coming, and why it doesn't just build towers instead of buying T-Mobile.
When the carrier responded, it came back as an official AT&T statement rather than an interview with a specific person. Imagine me sitting back in a chair chatting to a gigantic blue globe somehow gifted with the power of speech, and see what AT&T has to say.
PCMag: What does LTE allow users to do that they can't accomplish with HSPA+?
AT&T: 4G LTE offers real-world speeds faster than other mobile broadband technologies. While our HSPA+ network is faster than 3G, 4G LTE enables users to stream video, download apps, and send and receive e-mail even faster. In addition, 4G LTE has lower latency than other mobile broadband technologies, which means more responsive performance for customers when they want it most.
Q: You're right now advertising both HSPA+ and LTE as "4G." How will you help consumers be able to tell the difference?
A: Our advertising makes it clear that “4G” (offered through our HSPA+ network) and “4G LTE” are different things. We are currently advertising 4G LTE only in markets where our 4G LTE service has launched.
Q: AT&T is promising to cover 70 million people with LTE by the end of the year. Verizon already covers 160 million. What controls the speed of your buildout?
A: AT&T has delivered five speed upgrades to its wireless network over the past few years—the latest of those being HSPA+—on the road to our 4G LTE rollout. We are the only carrier that’s taken this additional step in order to provide our customers with a fast network experience even before 4G LTE is ubiquitous. Several of our competitors have chosen not to upgrade the speeds on their 3G networks, which means that their 4G LTE customers will experience steep drop-offs in speed as they fall back to 3G.
Q: How much spectrum is being used in each of the five LTE launch markets? 5x5, 10x10, 15x15? (Spectrum affects speed; for more on that, see "Why is AT&T LTE Fast in Houston, Slow in Chicago?")
A: We are currently using 10x10 in Atlanta, Dallas, Houston, and San Antonio, and are using 5x5 in Chicago.
Q: All the major carriers are being criticized for imposing the same data caps on LTE as they do on 3G. Will data caps rise anytime soon, to allow for new higher-bandwidth LTE applications?
A: We can’t speculate on future offerings.
Q: Why is buying T-Mobile important to AT&T's LTE strategy; why not just spend that $39 billion building towers and cell sites?
A: Integrating T-Mobile into AT&T’s network brings a whole lot of additional efficiencies and capacity gains that AT&T could not get just by building a lot of new cell sites, which would not be feasible in the same time period. Those include improved network utilization, channel pooling, the elimination of redundant control channels, and other efficiencies that effectively provide the functional equivalent of new spectrum.
Q: We've been seeing very different results in the different LTE cities. Why is that? Do you see speeds becoming more even in the future?
A: There are many things that factor in to wireless network speeds—spectrum, geography, terrain, device, etc. It’s difficult to speculate on what might happen in the future, but our proposed merger with T-Mobile gives us more capacity and spectrum.
Q: When will we see the first AT&T LTE phones?
A: We plan to offer a 4G LTE handset later this year.
Q: Will AT&T go to VoLTE (voice-over-LTE)? Will you use wider-band codecs than you do on 3G, for better voice quality?
A: We are committed to deploying voice over 4G LTE as our 4G LTE footprint is built out further and we have technology in place to ensure our customers have a great experience with voice over 4G LTE.
Q: Will AT&T's LTE ever interoperate or roam with other LTE networks, such as Verizon's or MetroPCS's? After all, you have 3G roaming.
A: It’s too soon to speculate on that. There are many technical challenges that must be addressed, due to the many different spectrum bands that carriers around the world are using to deploy 4G LTE.