Update: T-Mobile, AT&T complete HSPA 7.2 upgrades

IDG News Service - T-Mobile USA has completed its deployment of a faster 3G technology across its national network, reaching more than 200 million U.S. residents with the high-speed data and voice system while getting ready to upgrade some areas to even higher speeds later this year.

The nation's fourth-largest carrier had promised last year it would finish rolling out HSPA 7.2 -- High-Speed Packet Access with a theoretical top speed of 7.2M bps (bits per second) -- by the end of 2009.

The carrier announced Tuesday it had achieved that goal. The news came out just before Google introduced the Nexus One handset, which will be sold by Google and run on T-Mobile's network. The Nexus One supports HSPA 7.2, as do the Motorola Cliq and T-Mobile MyTouch 3G Android phones, the webConnect USB modem and other devices.

AT&T also announced on Tuesday that it had deployed HSPA 7.2 at all its 3G cell sites. That deployment seemed to come earlier than the company had promised.

While most mobile operators look toward LTE (Long-Term Evolution) as the next major generation of mobile data networks, 3G technology continues to evolve with higher performance and greater efficiency. Both AT&T and T-Mobile have said they will deploy LTE in 2011, a year later than Verizon Wireless, while upgrading on the 3G path in the meantime.

AT&T said last year it would have HSPA 7.2 in at least six markets, including Chicago, Los Angeles and Miami, by the end of 2009. The new technology will reach 90 percent of AT&T's network by the end of 2011, the company said last October.

AT&T is following up with improvements to its fiber backhaul connections to provide higher capacity for mobile data traffic all the way across the network. The backhaul is being upgraded city by city, and AT&T expects to have a majority of its mobile data traversing the fast fiber links by the end of this year, with more backhaul upgrades in 2011. The iPhone 3G S and nine other AT&T phones can use HSPA 7.2.

Now that T-Mobile's network is upgraded to HSPA 7.2, the carrier is gradually adding a faster technology, HSPA+, which is designed to deliver about 21M bps. The new network is live now in parts of central Philadelphia, said David Henderson, of T-Mobile's public relations agency, Waggener Edstrom. T-Mobile doesn't sell any HSPA+ devices, but the upgrade improves performance for existing devices because it brings more capacity, Henderson said. By the middle of this year, T-Mobile will have HSPA+ across its entire 3G footprint, he said.

The upgrades announced on Tuesday only cover the current 3G portions of each carrier's network. Other parts of their networks use an earlier form of GSM (Global System for Mobile Communications) called EDGE (Enhanced Data Rates for GSM Evolution).

Verizon Wireless, which uses a different 3G system from AT&T and T-Mobile, plans to launch commercial LTE service this year. LTE has been demonstrated at speeds of more than 100M bps downstream. Real-world speeds on all mobile networks depend on local conditions and typically are shared among many subscribers.