Earlier today, AT&T announced it will be the first operator in the United States to use the newly-established LTE-Advanced technique, ‘Carrier Aggregation’, to produce significantly faster 4G upload and download speeds on its rapidly-growing LTE network, which coincidently still holds the title of being the fastest in the U.S.

If you’re curious to know how the ‘Carrier Aggregation’ technique works, it simply combines two 4G networks to create a big boost in browsing speeds on LTE-enabled smartphones and tablets. Obviously, in order to successfully rollout its new service across the whole of the U.S., AT&T will need to distribute some new, up-to-date cellular hardware; which is why the operator vows to deploy approximately 10,000 new macro cell sites and over 40,000 smaller ones all around the United States before the end of 2015 as part of its VIP Investment Plan.

At this precise moment in time, Chicago is the first and only named city that the new LTE-Advanced service is live in, although we do believe there are others. Don’t get too excited at this point, though, as unfortunately only one device currently available to purchase is capable of using the new network and that is Unite’s mobile hotspot. However, a recent FCC filing suggests that Samsung’s upcoming flagship smartphone of 2014, the Galaxy S5, will be the first handset to support ‘Carrier Aggregation’.

Chicago is just the first location on AT&T’s map, the service will continue to expand across the United States over the course of the next two years until it’s accessible in all of the locations that the operators standard LTE network is currently live in.

• SourceGigaom