J band

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NATO J band
Frequency range
10 - 20 GHz
Wavelength range
3 – 1.5 cm
Related bands

J band can refer to three different regions of the electromagnetic spectrum, in the radio and near-infrared.

NATO[edit]

The NATO J band is the range of radio frequencies from 10 GHz to 20 GHz in the system of letter designations for frequency bands used by the NATO for electronic countermeasure (ECM) applications.[1][2] This is equivalent to wavelengths between 3 and 1.5 centimetres (1.18 and 0.59 in).

The J band is a subset of the SHF band as defined by the ITU.[3] The J band intersects with the X band and K band of the older IEEE classification system.[4] The Ku band is within the J band.[4]

Uses[edit]

The J band is used for satellite communications and radar, the latter being central to aircraft systems and their avionics. Satellite communications systems can be used in conjunction with aircraft to help locate and identify enemy targets or provide a role as a reconnaissance platform for soldiers on the ground.

JRC[edit]

In the United Kingdom, the term "J Band" is also used by the Joint Radio Company to refer to their VHF communications band at 139.5-140.5 and 148-149 MHz used by fuel and power industries.[5]

Infrared astronomy[edit]

Atmospheric windows in the infrared. The J band is the transmission window centred on 1.25 micrometres

In infrared astronomy, the J band refers to an atmospheric transmission window centred on 1.25 micrometres (in the near-infrared). Betelgeuse is the brightest near-IR source in the sky with a J band magnitude of -2.99.[6] The next brightest stars in the J band are R Doradus (-2.6), Arcturus (-2.2), and Aldebaran (-2.1).[7] In the J band Sirius is the 9th brightest star.

References[edit]

  1. ^ Leonid A. Belov; Sergey M. Smolskiy; Victor N. Kochemasov (2012). Handbook of RF, Microwave, and Millimeter-Wave Components. Artech House. pp. 27–28. ISBN 978-1-60807-209-5. 
  2. ^ Norman Friedman (2006). The Naval Institute Guide to World Naval Weapon Systems. Naval Institute Press. pp. xiii–xiv. ISBN 978-1-55750-262-9. 
  3. ^ "V.431: Nomenclature of the frequency and wavelength bands used in telecommunications". ITU-R. 2006-01-04. Retrieved 2014-02-03. 
  4. ^ a b "521-2002 - IEEE Standard Letter Designations for Radar-Frequency Bands". IEEE. 2003-01-14. doi:10.1109/IEEESTD.2003.94224. Retrieved 2014-02-03. (subscription required (help)). 
  5. ^ Joint Radio Company
  6. ^ R. Cutri and M. Skrutskie (2009-09-07). "Very Bright Stars in the 2MASS Point Source Catalog (PSC)". The Two Micron All Sky Survey at IPAC. Retrieved 2011-12-28. 
  7. ^ "Simbad object query:Jmag<-2 & Vmag>-9". SIMBAD Astronomical Database. Retrieved 2012-08-22. 

See also[edit]