GSM cellular service under the Cellular One brand, GCI formerly sold GSM cellular service under its own name while providing Dobson with the back-end network infrastructure. AT&T's purchase of Dobson, however, resulted in an agreement on December 3, 2007, that released Dobson, now under the AT&T Wireless brand, from its contract to use GCI for its back-end network on July 1, 2008; AT&T Wireless now uses existing AT&T Alascom networks. GCI will continue to contract with AT&T Wireless for the use and resale of its products and services through June 30, 2012, but will also invest $100 million in its own network. It also plans to spend approximately $10 million to complete its acquisition of the remaining 20% of Alaska DigiTel, a competing CDMA-based cellular carrier. On December 4, 2014, GCI agreed to purchase the wireless assets of Alaska Communications for $300 million. The deal is expected to close in the first quarter of 2015. Radio frequency spectrum chart The following chart describes radio frequency spectrum bands accessible by the company's customers. See also List of United States telephone companies Other cable based services 2010 Alaska Turbo Otter crash References External links GCI SchoolAccess GCI ConnectMD 1979 establishments in Alaska Cable television companies of the United States Communications in Alaska Companies based in Anchorage, Alaska Companies listed on the Nasdaq Technology companies established in 1979 Telecommunications companies of the United States