Frequency modulation

The Audio Signal (top) is transmitted on a carrier wave by modifying the amplitude (middle) or frequency (bottom)

Frequency modulation (FM) is a signaling method that varies the carrier frequency in proportion to the amplitude of the modulating signal.

Frequency modulation is most commonly used in radio, amateur radio, radar, telemetry, seismic prospecting, and in the monitoring of newborns for seizures via EEG.

See also

• Radio communication technologies

• Radio: Electromagnetic wave, Frequency, modulation, amplitude, amplitude modulation (AM), Shortwave, Walkie-talkie, Citizens band radio, General Mobile Radio Service (GMRS), and Multi-Use Radio Service

• Amateur Radio: Selecting a radio, and Telegraph

• Antenna (radio): Dipole antenna, Homebrew antennas, and Propagation
• Radio Standards Organization: FCC, American Radio Relay League

• Satellite: GPS
• Cellular telephone:
  • Apple iOS for iPhone or iPad
  • Android
  • Blackberry
  • Microsoft Windows Phone with Windows 8
  • Cell phone health scare, Mobile phones and brain tumor risk
• Bug-out bag

Further reading

• A. Bruce Carlson. Communication Systems, 4th edition. McGraw-Hill Science/Engineering/Math. 2001. ISBN 0-07-011127-8, ISBN 978-0-07-011127-1.
• Gary L. Frost. Early FM Radio: Incremental Technology in Twentieth-Century America. Baltimore: Johns Hopkins University Press, 2010. ISBN 0-8018-9440-9, ISBN 978-0-8018-9440-4.
• Ken Seymour, AT&T Wireless (Mobility). Frequency Modulation, The Electronics Handbook, pp 1188-1200, 1st Edition, 1996. 2nd Edition, 2005 CRC Press, Inc., ISBN 0-8493-8345-5 (1st Edition).

External links

• A Walkie Talkie For your BOB
• Two Way Radio Range Estimates