K band

K band

NATO K band
Frequency range	20 – 40 GHz
Wavelength range	1.5 cm – 7.5 mm
Related bands	K / Ka bands (IEEE) SHF / EHF (ITU)
IEEE K band
Frequency range	18 – 27 GHz
Wavelength range	1.67 – 1.11 cm
Related bands	J / K bands (NATO) SHF (ITU)

K band designates certain portions of the electromagnetic spectrum, in either the microwave domain or in the infrared domain. The microwave K bands are used primarily for radar and satellite communications while the infrared K band is used for astronomical observations.

NATO K band

The NATO K band is the obsolete designation given to the radio frequencies from 20 to 40 GHz (equivalent to wavelengths between 1.5 and 0.75 cm) during the cold war period. Since 1992 frequency allocations, allotment and assignments are in line to NATO Joint Civil/Military Frequency Agreement (NJFA).^[1] However, in order to identify military radio spectrum requirements, e.g. for crises management planning, training, Electronic warfare activities, or in military operations, this system is still in use.

NATO Radio spectrum designation
LATEST SYSTEM			ALTERNATIVE SYSTEM
BAND	FREQUENCY (MHz)		BAND	FREQUENCY (MHz)
A	0 – 250		I	100 – 150
B	250 – 500		G	150 – 225
C	500 – 1 000		P	225 – 390
D	1 000 – 2 000		L	390 – 1 550
E	2 000 – 3 000		S	1 550 – 3 900
F	3 000 – 4 000		C	3 900 – 6 200
G	4 000 – 6 000		X	6 200 – 10 900
H	6 000 – 8 000		K	10 900 – 36 000
I	8 000 – 10 000		Ku	10 900 – 20 000
J	10 000 – 20 000		Ka	20 000 – 36 000
K	20 000 – 40 000		Q	36 000 – 46 000
L	40 000 – 60 000		V	46 000 – 56 000
M	60 000 – 100 000		W	56 000 – 100 000

IEEE K band

The IEEE K band is a portion of the radio spectrum in the microwave range of frequencies ranging between 18 and 27 GHz. K band between 18 and 26.5 GHz is absorbed easily by water vapor (H₂O resonance peak at 22.24 GHz, 1.35 cm).

Subdivisions

The IEEE K band is conventionally divided into three sub-bands:

• K_a band: K-above band, 26.5–40 GHz, mainly used for radar and experimental communications. NASA's Kepler spacecraft is the first NASA mission to use K_a band DSN communications.^[2]
• K-band 18–27 GHz
• K_u band: K-under band, 12–18 GHz, mainly used for satellite communications, terrestrial microwave communications, and radar, especially police traffic-speed detectors.

Amateur radio

The Radio Regulations of the International Telecommunication Union allow amateur radio and amateur satellite operations in the frequency range 24.000 GHz to 24.250 GHz, which is known as the 1.2-centimeter band. It is also referred to as the K band by AMSAT.

Infrared astronomy

In infrared astronomy, the K band refers to a different frequency range atmospheric transmission window centered on 2.2 µm (in the near-infrared 136 THz range).

References

1. NATO Joint Civil/Military Frequency Agreement (NJFA)
2. http://www.nasa.gov/mission_pages/kepler/news/keplerm-20110617.html#.VK7w_SeE0fo