AT&T to double wireless data speeds in 6 cities

(AP) -- Chicago, Dallas, Houston, Los Angeles, Miami and Charlotte, N.C., will be the first cities to see the benefits of AT&T's plans to double the data download speeds on its wireless network. The six cities will be upgraded before the end of the year, the carrier said Wednesday.

The iPhone 3GS is the only phone on the market now that will be able to take advantage of the speed increase. But AT&T pointed to five other "smart" phones and some USB dongles, which let laptops go online, that will go on sale before the end of the year. Those devices also will be able to take advantage of the new technology, known as HSPA, or High-Speed Packet Access.

IPhone users have complained of slow data service that appears to be the result of congestion on the wireless network, something the network upgrade could alleviate.

The upgrade provides for a theoretical top download speed of 7.2 megabits per second, up from 3.6 megabits per second, which in practice translated to speeds of about 1.4 megabits per second.

With the upgrade, AT&T will overtake Verizon Wireless in download speeds, but not for long. Verizon Wireless is planning to go live next year with a new technology that it believes will give average speeds of 7 megabits per second to 12 megabits per second. Sprint Nextel Corp.'s part-owned Clear service provides speeds of 4 megabits per second in practice.

Several European and Asian countries have already deployed the 7.2-megabit version of HSPA, and a few have gone to 14.4 megabits per second.