AT&T recently demonstrated a fast 28.87 Mbps download speed during an LTE test at a Plano, Texas, lab, but an AT&T spokesman later warned not to extrapolate that real-world speeds will reach that level when AT&T launches its LTE wireless network this summer.
That test scenario represented an attempt to model a real-world situation, according to an AT&T engineer cited in a GigaOm report, although the GigaOm reporter who saw the demo noted that the 28.87Mbps speed will drop when a wireless user shares the same cell tower with others.
On Friday, an AT&T spokesman clarified: "The LTE network at the Foundry [facility in Plano] is not a production network and you can't extrapolate from the speeds recorded there what real-world speeds will be on AT&T's production network. We haven't announced anticipated speeds for our LTE production network."
AT&T's 28.87Mbps download speed and 10.4Mbps for uploads in that demo is more than double the LTE speeds that Verizon Wireless advertises for smartphones running on its LTE network, which has 12Mbps download speeds and up to 5Mbps for uploads.
The tests at the Foundry lab have relied on using MIMO (Multiple Input Multiple Output) antennas and two spectrum bands, at 700MHz and 1700MHz, AT&T said.
Several AT&T executives have noted that AT&T is taking its time to thoroughly test LTE before deploying it this summer. They made such comments even as Verizon recently underwent a nearly two-day LTE outage.
If AT&T ends up advertising its LTE as faster than Verizon's, that will be interesting, since LTE is a relatively new technology that could suffer outages and variations in speeds for many reasons, including an increase in the number of users per tower, analysts noted.
Some users might not even care about an improvement of 14Mbps in speed with AT&T over Verizon, since LTE, even at 5Mbps, is 10 times faster than most 3G speeds, analysts added.
However, given the way AT&T and Verizon clamor over every nuance of their respective wireless services, it seems likely that AT&T could be preparing for a marketing battle with Verizon over LTE speeds and reliability.
Phillip Redman, an analyst at Gartner, put AT&T's 28Mbps demonstration in perspective Friday: "There are so many variables when it comes to wireless bandwidth that the only thing to expect is variability. Though top speeds can test out to over 30Mbps on LTE networks, it is better to look at average speeds in-market, under real conditions. It is expected than that average [LTE] speeds will be under 10Mbps, and probably even half that on a loaded network."
Matt Hamblen covers mobile and wireless, smartphones and other handhelds, and wireless networking for Computerworld. Follow Matt on Twitter at @matthamblen or subscribe to Matt's RSS feed. His e-mail address is firstname.lastname@example.org.