T-Mobile USA on Thursday announced that it has doubled the speed of its 4G network in additional 41 markets in the United States, bringing the faster service to a total of 96 cities in the country.

The new cities where T-Mobile's faster HSPA+ network is launched on Thursday include Sacramento, San Diego, Cleveland, Salt Lake City and San Antonio, and the upgraded network can theoretically offer speed of up to 42 Mbps.

In a statement, T-Mobile said it expects more than 150 million Americans to have access to these increased 4G speeds by mid-2011 and customers can choose from more than a dozen 4G devices including smartphones and tablet computers.

According to the company, its slower 4G network with a peak speed of 21 Mbps has already covered more than 200 million Americans in 184 cities.

Based in Bellevue in the state of Washington, T-Mobile is the fourth-largest wireless carrier in the U.S. market.