AT&T is looking to deploy an upgraded high-speed packet access (HSPA) network in six US cities this year. The company spoke of doubling its 3G networks from a 3.6Mb/s downlink to 7.2Mbps months ago, but failed to define a specific launch plan. Today it announced that it would bring the upgraded network to customers in Charlotte, Chicago, Dallas, Houston, Los Angeles, and Miami.

By the end of this year subscribers in those six cities will have access to a peak speed of 7.2Mb/s downlink -- although, it's only a theoretical figure that customers are unlikely to experience in the real world. AT&T hopes to upgrade some 90% of its 3G network by the end of 2011, after which the carrier will begin its transition to 4G Long Term Evolution (LTE) technology.

Perhaps a smooth transition to a quicker network will boost AT&T's crummy customer approval ratings. While I have few complains after using the carrier for nearly two years, according to a recent Gartner Research study, the firm received the most complaints about AT&T's network. Gartner also noted that AT&T's actual mobile network averages are between 300Kb/s and 700Kb/s lower than expected.