Ku band

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The correct title of this article is K_u band. It features superscript or subscript characters that are substituted or omitted because of technical limitations.

The K_u band (pronounced "kay-yoo"; K-under band) is a portion of the electromagnetic spectrum in the microwave range of frequencies ranging from 10 to 18 GHz.

K_u band is primarily used for satellite communications, particularly for satellite backhauls from remote locations back to a television network's studio for editing and broadcasting. The band is split into multiple segments that vary by geographical region by the International Telecommunication Union (ITU).

NBC was the first television network to uplink a majority of its affiliate feeds via K_u band in 1983.

1 Segments and regions
2 Limits
3 See also
4 External links

[edit] Segments and regions

[edit] The Americas

Segments in most of the Americas are represented by (ITU Region 2) and they are, the 11.7 to 12.2 GHz (LOF 10.750 GHz) band is allocated to the FSS (fixed service satellite, uplink 14.0 to 14.5 GHz). There are more than 22 FSS K_u-band satellites orbiting over North America, each carrying 12 to 24 transponders, 20 to 120 watts per transponder, and requiring a 0.8-m to 1.5-m antenna for clear reception.

The 12.2 to 12.7 GHz (LOF 11.250 GHz) segment is allocated to the BSS (broadcasting satellite service). BSS/DBS direct broadcast satellites normally carry 16 to 32 transponders of 27 MHz bandwidth running at 100 to 240 watts of power, allowing the use of receiver antennas as small as 18 inches (450 mm).

[edit] Europe and Africa

Segments in those regions are represented by (ITU Region 1) and they are, the 11.45 to 11.7 and 12.5 to 12.75 GHz bands are allocated to the FSS (fixed satellite service, uplink 14.0 to 14.5 GHz).

In Europe K_u band is used from 10.7 to 12.75 GHz (LOF Low 9.750 GHz, LOF High 10.600 GHz) for Direct Broadcast Satellite services like SES Astra.

The 11.7 to 12.5 GHz segment is allocated to the BSS (broadcasting satellite service).

[edit] Others

Other ITU allocations have been made within the K_u band to the Fixed Service (microwave towers), Radio Astronomy Service, Space Research Service, Mobile Service, Mobile Satellite Service, Radiolocation Service (radar), Amateur Radio Service, and Radionavigation. However, not all of these services are actually operating in this band and others are only minor users.

[edit] Limits

K_u band signals can be affected by rain attenuation (rain fade). In case of TV reception, only heavy rainfalls (>100 mm/hr) will have noticeable effect for the user.

[edit] See also

Satellite internet

[edit] External links

http://www.ntia.doc.gov/osmhome/allochrt.pdf

The Electromagnetic Spectrum (Sorted by wavelength, short to long)
Gamma ray \| X-ray \| Ultraviolet \| Visible spectrum \| Infrared \| Terahertz radiation \| Microwave \| Radio waves
Visible (optical) spectrum:	Violet \| Blue \| Green \| Yellow \| Orange \| Red
Microwave spectrum:	W band \| V band \| K band: K_a band, K_u band \| X band \| C band \| S band \| L band
Radio spectrum:	EHF \| SHF \| UHF \| VHF \| HF \| MF \| LF \| VLF \| ULF \| SLF \| ELF
Wavelength designations:	Microwave \| Shortwave \| Mediumwave \| Longwave