4G World: AT&T says HSPA+ is off the table for now

AT&T’s plans to upgrade through the different iterations of 3G look like they will come to halt after its current round of high-speed packet access (HSPA) is complete. At her keynote at 4G World in Chicago today, Kris Rinne, AT&T’s (NYSE:T) senior vice president of architecture and planning, said AT&T will hold as an option future upgrades to evolved HSPA (or HSPA+), which would boost current 3G network capacities by a factor of six. But currently the carrier’s plans call for proceeding directly toward 4G in 2010.

“Our plans on the infrastructure side focus on LTE rather HSPA+,” Rinne said. AT&T isn’t writing the technology off, she said —the operator will continue to follow the technology and support its network and handset suppliers in development and standardization efforts, but it no longer has any specific plans or timeline for deployment.

Rinne’s revelation wasn’t entirely unexpected, given that last week AT&T announced a new 3G/4G roadmap that didn’t include any mention of HSPA+. Originally the operator planned to double its current HSPA networks--which support theoretical peak speeds of 3.6 Mb/s--starting this year, following them up with an advanced upgrade to HSPA+ next year—which would have increased theoretical speeds to more than 21 Mb/s. The culmination of AT&T’s plan is the launch of its first long-term evolution (LTE) networks in 2011.

AT&T’s new strategy appears to cut HSPA+ out of the mix. The upgrade to 7.2 Mb/s HSPA will take place gradually over the next two years concurrently with an initiative to add more 3G channels in its current markets and upgrade AT&T’s backhaul networks with fiber in preparation for the huge capacity demands of LTE.

The huge popularity of the iPhone along with the increasing number of other data-hungry smartphones, netbooks and embedded consumer electronics devices has already taken a toll on the 3G network, and Rinne said AT&T is not only aware but actively addressing those capacity issues. In her presentation, she showed that data traffic on the 3G network has grown by almost 5000% in the last three years.

“I know what you’re thinking: It’s all about the iPhone,” she said. While AT&T now supports an impressive 8.3 million smartphones on its networks, she said, it has also seen a huge surge in traffic from mobile broadband, email and even M2M connections.

The upgrade to 7.2 Mb/s along with the addition of new HSPA data carriers and removing choke points in the backhaul network will ease many of those problems. But the advent of LTE in 2011 will provide the ultimate antidote. Not only will AT&T be able to deliver far more capacity over the new network, it will be able to deliver it much more efficiently and cheaply. Rinne estimated that the cost of delivering a megabit per second of capacity over LTE was just 3% the cost of delivering that same megabit on an EDGE network, compared to the 14% of the EDGE’s cost on the HSPA network.