Band (radio)

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A band is a small section of the spectrum of radio communication frequencies, in which channels are usually used or set aside for the same purpose. Examples include:

• AM broadcast band (530–1610 kHz or to 1710 kHz on the extended AM band in the Americas)
• Various Shortwave bands (5.9–26.1 MHz)
• Citizens' band (26.965–27.405 MHz)
• Television stations 2–6 (54–88 MHz in the Americas)
• FM broadcast band (88–108 MHz, except 76–90 MHz in Japan)
• Airband (108–137 MHz) for air traffic control
• Television stations 7–13 (174–216 MHz in the Americas)
• L band (1,452–1,492 MHz) for digital radio (DAB) outside the United States
• Amateur radio bands among several different frequencies
• Military bands:
  • FM band (35-87.9 MHz)
  • X band (8–10 GHz)
  • S band (1750–2400 MHz)
• K band (20–40 GHz), which is further subdivided:
  • K_a band: K-above band, 27–40 GHz, mainly used for radar and general communications
  • K_u band: K-under band, 12–18 GHz, mainly used for satellite communications
• Radionavigation beacons, such as LORAN and GPS
• V band (50–75 GHz)
• Various amateur radio bands

Each of these bands has a basic bandplan which dictates how it is to be used and shared, to avoid interference and to set protocol for the compatibility of transmitters and receivers.

Note that as a matter of physics, bands are divided at wavelengths of 10ⁿ metres, or frequencies of 3×10ⁿ hertz. For example, 30 MHz or 10 m divides shortwave (lower and longer) from VHF (shorter and higher). These are the parts of the radio spectrum, and not its frequency allocation.