ITU frequency bands: Difference between revisions

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imported>Bruce M. Tindall
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imported>Howard C. Berkowitz
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| 30-300 GHz
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| EHF (Extremely High Frequency; "millimeter wave")
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Millimeter wave frequencies begin at 18 GHz in SHF and go to the lower third of EHF. Submillimeter wave start roughly above 100 GHz; they blur into the longer [[infrared light]] frequencies.

Revision as of 21:13, 13 November 2008

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The International Telecommunications Union has defined a system of terminology for electromagnetic frequencies used for radio and radar. While it is probably the most user-friendly of the three major systems in use, its categories are too coarsely grained for describing radar uses. It is, however, a good set of terms for frequencies used in communications.

See IEEE frequency bands for radar designations used widely in civilian practice, and the EU-NATO-US frequency bands for a nomenclature that works well in fine-grained radar band discussion.

The very lowest bands have no radar applications, but, among other things, have a critical military application in communicating, at a very low data rate, with submerged submarines.

Frequency range ITU band
3-30 Hz ELF (Extremely Low Frequency)
30Hz to 300Hz SLF (Super Low Frequency)
300Hz to 3000Hz ULF (Ultra Low Frequency)
3kHz to 30kHz VLF (Very Low Frequency)
30-300 KHz LF (Low Frequency; "longwave")
300KHz-3 MHz MF (Medium Frequency; "medium wave")
3-30 MHz HF (High Frequency; "shortwave")
30-300 MHz VHF (Very High Frequency)
300 MHz -3 GHz UHF (Ultra High Frequency)
3-30 GHz SHF (Super High Frequency)
30-300 GHz EHF (Extremely High Frequency)

Millimeter wave frequencies begin at 18 GHz in SHF and go to the lower third of EHF. Submillimeter wave start roughly above 100 GHz; they blur into the longer infrared light frequencies.