Airphone

Air-ground radiotelephone service includes commercial and general aviation services. Licensees may offer a wide range of telecommunications services to passengers and others on aircraft.

The air-ground radiotelephone service operates on frequencies designated by the Federal Communications Commission.

A U.S. air-ground radiotelephone transmits a radio signal in the 849 to 851 megahertz range; this signal is sent to either a receiving ground station or a communications satellite depending on the design of the particular system. "Commercial aviation air-ground radiotelephone service licensees operate in the 800 MHz band and can provide communication services to all aviation markets, including commercial, governmental, and private aircraft." If it is a call from a commercial airline passenger radiotelephone, the call is then forwarded to a verification center to process credit card or calling card information. The verification center will then route the call to the public switched telephone network, which completes the call. For the return signal, ground stations and satellites use a radio signal in the 894 to 896 megahertz range.

Two separate frequency bands have been allocated by the FCC for air-ground telephone service. One at 454/459 MHz, was originally reserved for "general" aviation use (non-airliners) and the 800 MHz range, primarily used for airliner telephone service, which has shown limited acceptance by passengers. AT&T Corporation abandoned its 800 MHz air-ground offering in 2005, and Verizon AIRFONE (formerly GTE Airfone) is scheduled for decommissioning in late 2008, although the FCC has re-auctioned Verizon's spectrum (see below). Skytel, (now defunct) which had the third nationwide 800 MHz license, elected not to build it, but continued to operate in the 450 MHz AGRAS system. Its AGRAS license and operating network was sold to Bell Industries in April, 2007.

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