J band

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ITU Radio Band Numbers

1 2 3 4 5 6 7 8 9 10 11 12

ITU Radio Band Symbols

ELF SLF ULF VLF LF MF HF VHF UHF SHF EHF THF

NATO Radio bands

A B C D E F G H I J K L M

IEEE Radar bands

HF VHF UHF L S C X Ku K Ka V W mm

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

Radio

The J band is the range of radio frequencies from 10 GHz to 20 GHz in the electromagnetic spectrum. This is equal to wavelengths between 3 and 1.5 centimetres (1.18 and 0.59 in). The J band is in the SHF range of the radio spectrum.

The J band intersects with the X band and K band of the older classification system. The Ku band is within the J band.

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.[1]

Infrared astronomy

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.[2] The next brightest stars in the J band are R Doradus (-2.6), Arcturus (-2.2), and Aldebaran (-2.1).[3] In the J band Sirius is the 9th brightest star.

Uses

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.

See also

ELF
3 Hz/100 Mm
30 Hz/10 Mm

SLF
30 Hz/10 Mm
300 Hz/1 Mm

ULF
300 Hz/1 Mm
3 kHz/100 km

VLF
3 kHz/100 km
30 kHz/10 km

LF
30 kHz/10 km
300 kHz/1 km

MF
300 kHz/1 km
3 MHz/100 m

HF
3 MHz/100 m
30 MHz/10 m

VHF
30 MHz/10 m
300 MHz/1 m

UHF
300 MHz/1 m
3 GHz/100 mm

SHF
3 GHz/100 mm
30 GHz/10 mm

EHF
30 GHz/10 mm
300 GHz/1 mm

THF
300 GHz/1 mm
3 THz/0.1 mm

← higher frequencies       longer wavelengths →

Visible (optical)
Microwaves
Radio
Wavelength types

References

  1. ↑ Joint Radio Company
  2. ↑ 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. 
  3. ↑ "Simbad object query:Jmag<-2 & Vmag>-9". SIMBAD Astronomical Database. Retrieved 2012-08-22. 


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