US mobile operator AT&T says it will upgrade six more markets with High Speed Uplink Packet Access (HSUPA) in the next month, completing its rollout of the technology. AT&T claims HSUPA offers uplink speeds of between 500 and 800 kb/s, and compliments existing download (HSDPA) speeds of up to 1.4 Mb/s. The company also claims its HSPA network will reach close to 350 US markets by year-end. It adds that around 75 percent of its handsets are 3G compatible.

The final stages of the rollout will mean AT&T has invested over US$20 billion in network enhancements since 2005 – an average of US$5 billion a year, the company claims. According to Information Week, the upgrade is expected to put AT&T on a par with rival operators Sprint Nextel and Verizon Wireless, which both offer mobile broadband based on CDMA technology. AT&T’s move to finalise its HSPA network could be linked to the rumoured arrival of the 3G iPhone, tipped for launch next month. AT&T is the exclusive distributor of the iPhone in the US.