Frequency Band

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Frequency Band [[/a>|/a> ]]</dt>
A continuous range of frequencies extending between two limiting frequencies. </dd>
Specific frequency bands used in radio and radar are often designated by names, numbers, or letters. The band designations as decided upon by the Atlantic City Radio Convention of 1947 and later modified by Comite Consultatif International Radio (CCIR) Recommendation No. 142 in 1953 were:

' <tbody> </tbody>
Band number Frequency range Metric subdivision waves Atlanctic City frequency subdivision
4 3- 30 Myriametric Very-low VLF
5 30- 300 Kilometric Low LF
6 300- 3,000 Hectometric Medium MF
7 3,000- 30,000 Decametric High HF
8 30- 300 Metric Very-high VHF
9 300- 3,000 Decimetric Ultra-high UHF
10 3,000- 30,000 Centimetric Super-high SHF
11 30,000- 300,000 Millimetric Extremely high EHF
12 300,000- 3,000,000 Decimillimetric -- --
'Note that band N extends from

0.3*10<math>N</math> to 3*10<math>N</math> cycles; thus band 4 designates the frequency range 0.3*104 to 3*104 cycles. The upper limit is included in each band; the lower limit is excluded. '</dd>
Description of bands by means of adjectives is arbitrary and the CCIR recommend that it be discontinued. '</dd>
The designation ELF, extremely low frequency, has recently been proposed for the band extending from 3 kilocycles down to 1 cycle per second. These frequencies have been used for years in the study of lightning and associated phenomena and may be useful in communicating with spacecraft. '</dd>
The frequency bands used by radar (radar frequency bands) were first designated by letters for military secrecy. Those designations were:

' <tbody> </tbody>
Frequency band
Approximate frequency range, gigacycles
Approximate wavelength range, centimeters
P-band 0.225 to 0.39 140 to 76.9
L-band 0.39 to 1.55 76.9 to 19.3
S-band 1.55 to 5.20 19.3 to 5.77
X-band 5.20 to 10.90 5.77 to 2.75
K-band 10.90 to 36.00 2.75 to 0.834
Q-band 36.00 to 46.00 0.834 to 0.652
V-band 46.00 to 56.00 0.652 to 0.536
'The C-band, 3.9 to 6.2 gigacycles,

overlaps the S- and X-bands. These letter designations have no official sanction. </dd>


This article is based on NASA's Dictionary of Technical Terms for Aerospace Use