FCC
(Federal Communications Commission)
The Federal Communications Commission (FCC) is an independent United States government agency, directly responsible to Congress. The FCC is charged with regulating interstate and international communications by radio, television, wire, satellite and cable. The FCC's jurisdiction covers the 50 states, the District of Columbia, and U.S. possessions.
The FCC's Office of Engineering and Technology (OET) certifies all mobile phones intended for use in the US, insuring compliance with spectrum allocations, technical standards, and safe SAR (radiation) levels.
The FCC also manages the spectum allocated to the various mobile phone carriers, via a system of licences. Each license covers a specific range (band) of frequncies, and a specific geographic area.