The Radio Portal

A variety of radio antennas on Sandia Peak near Albuquerque, New Mexico, United States

Radio is the technology of communicating using radio waves. Radio waves are electromagnetic waves of frequency between 3 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transmitter connected to an antenna which radiates oscillating electrical energy, often characterized as a wave. They can be received by other antennas connected to a radio receiver; this is the fundamental principle of radio communication. In addition to communication, radio is used for radar, radio navigation, remote control, remote sensing, and other applications.

In radio communication, used in radio and television broadcasting, cell phones, two-way radios, wireless networking, and satellite communication, among numerous other uses, radio waves are used to carry information across space from a transmitter to a receiver, by modulating the radio signal (impressing an information signal on the radio wave by varying some aspect of the wave) in the transmitter. In radar, used to locate and track objects like aircraft, ships, spacecraft and missiles, a beam of radio waves emitted by a radar transmitter reflects off the target object, and the reflected waves reveal the object's location to a receiver that is typically colocated with the transmitter. In radio navigation systems such as GPS and VOR, a mobile navigation instrument receives radio signals from multiple navigational radio beacons whose position is known, and by precisely measuring the arrival time of the radio waves the receiver can calculate its position on Earth. In wireless radio remote control devices like drones, garage door openers, and keyless entry systems, radio signals transmitted from a controller device control the actions of a remote device. (Full article...)

An Iridium satellite for satellite telephony

A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a transponder; it creates a communication channel between a source transmitter and a receiver at different locations on Earth. Communications satellites are used for television, telephone, radio, internet, and military applications. Many communications satellites are in geostationary orbit 22,236 miles (35,785 km) above the equator, so that the satellite appears stationary at the same point in the sky; therefore the satellite dish antennas of ground stations can be aimed permanently at that spot and do not have to move to track the satellite. Others form satellite constellations in low Earth orbit, where antennas on the ground have to follow the position of the satellites and switch between satellites frequently.

The radio waves used for telecommunications links travel by line of sight and so are obstructed by the curve of the Earth. The purpose of communications satellites is to relay the signal around the curve of the Earth allowing communication between widely separated geographical points. Communications satellites use a wide range of radio and microwave frequencies. To avoid signal interference, international organizations have regulations for which frequency ranges or "bands" certain organizations are allowed to use. This allocation of bands minimizes the risk of signal interference. (Full article...)

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Formats Community radio, Music radio, Old-time radio, Radio comedy, Radio documentary, Radio drama, Sports radio, Talk Radio, Top 40
Networks BBC Radio, Blue Network, Columbia Broadcasting System, Mutual Broadcasting System, National Broadcasting Company, Sirius Satellite Radio, XM Satellite Radio
People Fred Allen, Gracie Allen, Don Ameche, Jack Benny, Edgar Bergen, Jagadish Chandra Bose, George Burns, Charlamagne tha God, Ronald Colman, Jim Connors, Frank Conrad, Norman Corwin, Charles Coughlin, Frankie Crocker, Ebro Darden, Alice Faye, Stan Freberg, Sean Hannity, Vaughn Harper, Phil Harris, Bob Hope, Hal Jackson, Spike Jones, Tom Joyner, Hans von Kaltenborn, Larry Elder, Larry King, Kay Kyser, Frances Langford, Rush Limbaugh, Guglielmo Marconi, Angie Martinez, Elizabeth McLeod, J. Carrol Naish, Ozzie Nelson, Arch Oboler, Dorothy Parker, Virginia Payne, Harold Peary, David Sarnoff, Red Skelton, Kate Smith, Stephen A. Smith, Howard Stern, Nikola Tesla, Jonathan Toubin, Lurene Tuttle, Rudy Vallée, Fred Waring, Orson Welles, Wendy Williams, Angela Yee
Shows Abbott and Costello, Amos 'n' Andy, Arch Oboler's Plays, The Breakfast Club, Burns and Allen, Cavalcade of America, CBS Radio Mystery Theater, Dragnet, Duffy's Tavern, Ebro in the Morning, Fibber McGee and Molly, The Goldbergs, The Howard Stern Show, Inner Sanctum Mysteries, The Jack Benny Program, Life with Luigi, Lights Out, Lux Radio Theater, Opie and Anthony, The Archers, The Hitchhiker's Guide to the Galaxy, The Phil Harris-Alice Faye Show, Quiz Kids, The Screen Guild Theater, The Shadow, Suspense, Theater Guild on the Air, Twenty Questions, The Whistler, Yours Truly, Johnny Dollar, Tom Joyner Morning Show, Rush Limbaugh Show
Technology Amateur radio, AM broadcasting, FM broadcasting, International broadcasting, Internet Radio, Digital Radio Mondiale, HD Radio, Digital Audio Broadcasting, GNU Radio, Software-defined radio, Transistor radio, Vacuum tube, Pirate radio

Top 40

Industry Radio promotion

WikiProjects

  • Radio December 12, 2006 "...to create, expand, and maintain Wikipedia articles related to radio, including radio propagation and reception, radio programming, radio personalities, and the business of radio." (Example: Mutual Broadcasting System)
  • Radio Stations February 15, 2005 "...to coordinate the activities of creating and maintaining articles about radio stations." (Example: Pulse FM Kingborough & Huon)
  • Podcasting January 21, 2007 "...to make Wikipedia's knowledge of notable Podcast and podcast-related information as complete as possible." (Example: Podcast)
  • Amateur Radio (Inactive), August 24, 2006 "...to improve Wikipedia's articles related to Amateur radio, maintain the amateur radio category and its sub-categories for clean organization, and to produce and maintain templates for Amateur radio-related topic identification." (Example: Amateur radio)

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