List of WLAN channels

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This list of WLAN channels is the set of legally allowed Wireless LAN channels using IEEE 802.11.

The 802.11 workgroup currently documents use in three distinct frequency ranges, 2.4 GHz, 3.6 GHz and 4.9/5.0 GHz bands.[1] Each range is divided into a multitude of channels. Countries apply their own regulations to both the allowable channels, allowed users and maximum power levels within these frequency ranges. In some countries, such as the United States, licensed Amateur Radio operators may use some of the channels at much higher power for long distance wireless access.

Contents

2.4 GHz (802.11b/g/n)

Graphical representation of Wireless LAN channels in 2.4 GHz band

There are 14 channels designated in the 2.4 GHz range spaced 5 MHz apart (with the exception of a 12 MHz spacing before Channel 14). As the protocol requires 25 MHz of channel separation, adjacent channels overlap and will interfere with each other. Consequently, using only channels 1, 6, 11 is recommended in the US to avoid interference.[2] In much of the world, the four channels 1, 5, 9, 13 are recommended. There are exceptions to this however, for example in the UK, where British Telecom recommend use of three channels 1, 6, 11[3]. Using the 3-channel system is recommended, since many existing access points are on channel 6 by factory default,[2] causing the channel 6 to be likely to be in use anyway.

Potential Wireless LAN by IEEE 802.11 clauses 18 (802.11b), 19 (802.11g) and 20 (802.11n). IEEE 802.11 clauses 14 and 15 also specify potential uses of this range, but did not see widespread implementation.

Countries apply their own regulations to both the allowable channels, allowed users and maximum power levels within these frequency ranges. Consult your local authorities as these regulations may be out of date as they are subject to change at any time. Most of the world will allow the first thirteen channels in the spectrum.

ChannelFrequency
(MHz)
North America
[4]
Japan[4]Most of worldA
[4][5][6][7][8]
1*2412YesYesYesD
22417YesYesYesD
32422YesYesYesD
42427YesYesYesD
5*2432YesYesYes
62437YesYesYes
72442YesYesYes
82447YesYesYes
9*2452YesYesYes
102457YesYesYes
112462YesYesYes
122467NoBYesYes
13*2472NoBYesYes
142484No11b onlyCNo
*With 802.11g and newer only the channels 1, 5, 9, and 13 shall be used in order to obey the non-overlapping 20 MHz OFDM channel scheme borrowed from 802.11a. But please do a site survey first, then if channel 6 is already heavily occupied, follow the 3-channel system.

^A Earlier, in Spain the only allowable channels were 10–11, and in France 10–13. These restrictions have been removed since, and these countries are currently following the common European policy (channels 1–13).

^B In the USA, 802.11 operation in the channels 12 and 13 is actually allowed under low powered conditions. The 2.4 GHz Part 15 band in the US allows spread-spectrum operation as long as the 50-dB bandwidth of the signal is within the range of 2,400–2,483.5 MHz[9] which wholly encompasses both channels 12 and 13. A Federal Communications Commission (FCC) document clarifies that only channel 14 is forbidden and furthermore low-power transmitters with low-gain antennas may legally operate in channels 12 and 13.[10] However, channels 12 and 13 are not normally used in order to avoid any potential interference in the adjacent restricted frequency band, 2,483.5–2,500 MHz,[11] which is subject to strict emission limits set out in 47 CFR §15.205.[12]

In Canada, 12 channels are available for use, 11 of which at full power and the other (channel 12) is transmit power limited. However, few devices have a method to enable a lower powered channel 12[opinion].

^C Channel 14 is valid only for DSSS and CCK modes (Clause 18 a.k.a. 802.11b) in Japan. OFDM (i.e., 802.11g) may not be used. (IEEE 802.11-2007 §19.4.2)

^D Outdoor use of channels 1–4 is not allowed in Israel, although indoor use is permitted.[13]

3.6 GHz (802.11y)

Except where noted, all information taken from Annex J of IEEE 802.11y-2008

This range is documented as only being allowed as a licensed band in the United States. Please see IEEE 802.11y for details.

Countries apply their own regulations to both the allowable channels, allowed users and maximum power levels within these frequency ranges.

ChannelFrequency
(MHz)
United States
5 MHz10 MHz20 MHz
1313657.5YesNoNo
1323662.5YesNoNo
1323660.0NoYesNo
1333667.5YesNoNo
1333665.0NoNoYes
1343672.5YesNoNo
1343670.0NoYesNo
1353677.5YesNoNo
1363682.5YesNoNo
1363680.0NoYesNo
1373687.5YesNoNo
1373685.0NoNoYes
1383689.5YesNoNo
1383690.0NoYesNo

4.9 GHz (802.11y) Public Safety WLAN

50 MHz of spectrum from 4940 MHz to 4990 MHz (WLAN channels 20–26) are in use by public safety entities in the United States. Within this spectrum space, there are two non-overlapping channels allocated, both with a width of 20 MHz. The most commonly used channels are 22 and 26.

5 GHz (802.11a/h/j/n)[14]

Countries apply their own regulations to both the allowable channels, allowed users and maximum power levels within these frequency ranges. Consult your local authorities as these regulations may be out of date as they are subject to change at any time.

European standard EN 301 893 covers 5.15-5.725 GHz operation, and v1.7.1 is in force.

In 2007 the FCC (United States) began requiring that devices operating on 5.250–5.350 GHz and 5.470–5.725 GHz must employ dynamic frequency selection (DFS) and transmit power control (TPC) capabilities. This is to avoid interference with weather-radar and military applications.[15] In 2010, the FCC further clarified the use of channels in the 5.470–5.725 GHz band to avoid interference with Terminal Doppler Weather Radar (TDWR) systems.[16] This statement eliminated the use of channels 120, 124, and 128. Channels 116 and 132 may be used, so long as they are separated by more than 30 MHz (center-to-center) from a TDWR located within 35 km of the device. There are now at least five relevant KDBs about operation in 5 GHz radar bands.

Germany requires dynamic frequency selection (DFS) and transmit power control (TPC) capabilities on 5.250–5.350 GHz and 5.470–5.725 GHz as well, in addition the frequency range 5.150–5.350 GHz is only allowed for indoor use, leaving only 5.470-5.725 GHz for outdoor and indoor use.[17]

Since this is the German implementation of EU-Rule 2005/513/EC, similar regulations must be expected throughout the European Union.[18][19]

Austria adopted Decision 2005/513/EC directly into national law.[20] The same restrictions as in Germany apply, only 5.470-5.5725 GHz is allowed to be used outdoor and indoor.

South Africa simply copied the European regulations.[21]

Japan no longer allows 34, 38, 42, and 46 channels for connecting J52 supported old APs. Authorization to use these channels expired in May 2012.

In Brazil, the TPC use in 5,150–5,725 MHz band is optional. DFS is required only in 5,470–5,725 MHz band.[22]

Australian DFS channels also require TPC, or the maximum allowed power is cut in half.[8]

ChannelFrequency
(MHz)
United StatesEuropeJapanSingaporeChinaIsraelKoreaTurkeyAustraliaSouth AfricaBrazil
40/20 MHz[23]40/20 MHz[citation needed]40/20 MHz[24]10 MHz40/20 MHz[25]20 MHz20 MHz[7]20 MHz[26]40/20 MHz[27]40/20 MHz[8]40/20 MHz[21]40/20 MHz[22]
1834915NoNoNoYesNoNoNoNoNoNoNoNo
1844920NoNoYesYesNoNoNoNoNoNoNoNo
1854925NoNoNoYesNoNoNoNoNoNoNoNo
1874935NoNoNoYesNoNoNoNoNoNoNoNo
1884940NoNoYesYesNoNoNoNoNoNoNoNo
1894945NoNoNoYesNoNoNoNoNoNoNoNo
1924960NoNoYesNoNoNoNoNoNoNoNoNo
1964980NoNoYesNoNoNoNoNoNoNoNoNo
75035NoNoNoYesNoNoNoNoNoNoNoNo
85040NoNoNoYesNoNoNoNoNoNoNoNo
95045NoNoNoYesNoNoNoNoNoNoNoNo
115055NoNoNoYesNoNoNoNoNoNoNoNo
125060NoNoNoNoNoNoNoNoNoNoNoNo
165080NoNoNoNoNoNoNoNoNoNoNoNo
345170NoNoClient only[clarification needed]NoYesNoYesYesIndoorsNoIndoorsIndoors
365180YesIndoorsYesNoYesNoYesYesIndoorsYesIndoorsIndoors
385190NoNoClient onlyNoYesNoYesYesIndoorsNoIndoorsIndoors
405200YesIndoorsYesNoYesNoYesYesIndoorsYesIndoorsIndoors
425210NoNoClient onlyNoYesNoYesYesIndoorsNoIndoorsIndoors
445220YesIndoorsYesNoYesNoYesYesIndoorsYesIndoorsIndoors
465230NoNoClient onlyNoYesNoYesYesIndoorsNoIndoorsIndoors
485240YesIndoorsYesNoYesNoYesYesIndoorsYesIndoorsIndoors
525260DFSIndoors/DFS/TPCDFS/TPCNoYesNoYesYesIndoorsDFS/TPCIndoorsIndoors
565280DFSIndoors/DFS/TPCDFS/TPCNoYesNoYesYesIndoorsDFS/TPCIndoorsIndoors
605300DFSIndoors/DFS/TPCDFS/TPCNoYesNoYesYesIndoorsDFS/TPCIndoorsIndoors
645320DFSIndoors/DFS/TPCDFS/TPCNoYesNoYesYesIndoorsDFS/TPCIndoorsIndoors
1005500DFS[16]DFS/TPCDFS/TPCNoNoNoNoYesDFS/TPCDFS/TPCYesDFS
1045520DFS[16]DFS/TPCDFS/TPCNoNoNoNoYesDFS/TPCDFS/TPCYesDFS
1085540DFS[16]DFS/TPCDFS/TPCNoNoNoNoYesDFS/TPCDFS/TPCYesDFS
1125560DFS[16]DFS/TPCDFS/TPCNoNoNoNoYesDFS/TPCDFS/TPCYesDFS
1165580DFS[16]DFS/TPCDFS/TPCNoNoNoNoYesDFS/TPCDFS/TPCYesDFS
1205600No[28]DFS/TPCDFS/TPCNoNoNoNoYesDFS/TPCNoYesDFS
1245620No[28]DFS/TPCDFS/TPCNoNoNoNoYesDFS/TPCNoYesDFS
1285640No[28]DFS/TPCDFS/TPCNoNoNoNoYesDFS/TPCNoYesDFS
1325660DFS[16]DFS/TPCDFS/TPCNoNoNoNoNoDFS/TPCDFS/TPCYesDFS
1365680DFS[16]DFS/TPCDFS/TPCNoNoNoNoNoDFS/TPCDFS/TPCYesDFS
1405700DFS[16]DFS/TPCDFS/TPCNoNoNoNoNoDFS/TPCDFS/TPCYesDFS
1495745YesSRD (25mW)[29]NoNoYesYesNoYesNoYesNoYes
1535765YesSRD (25mW)[29]NoNoYesYesNoYesNoYesNoYes
1575785YesSRD (25mW)[29]NoNoYesYesNoYesNoYesNoYes
1615805YesSRD (25mW)[29]NoNoYesYesNoYesNoYesNoYes
1655825YesSRD (25mW)[29]NoNoYesYesNoYesNoYesNoYes

See also

In Japan, authorization to use channels 34, 38, 42 and 46 expired in May 2012, seven years after channels 36, 40, 44 and 48 were initially allowed. ARIB STD T-71v5_2 clause 5.3.8.3.3 lists permitted channels.

References

  1. ^ "IEEE 802.11-2007: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) specifications". IEEE. 2007-03-08. http://standards.ieee.org/getieee802/802.11.html.
  2. ^ a b "Change the WiFi Channel Number to Avoid Interference". http://compnetworking.about.com/od/wifihomenetworking/qt/wifichannel.htm.
  3. ^ "How do I change the wireless channel on my BT Home Hub 3?". http://btybb.custhelp.com/app/answers/detail/a_id/32236/~/how-do-i-change-the-wireless-channel-on-my-bt-home-hub-3%3F.
  4. ^ a b c IEEE 802.11-2007 — Table 18-9
  5. ^ France: "WLAN regulatory update". 2003-02-03. http://www.arcep.fr/index.php?id=8571&L=1&tx_gsactualite_pi1%5Buid%5D=232&tx_gsactualite_pi1%5Bannee%5D=2003&tx_gsactualite_pi1%5Btheme%5D=0&tx_gsactualite_pi1%5Bmotscle%5D=&tx_gsactualite_pi1%5BbackID%5D=2122&cHash=a558568045.
  6. ^ Spain: http://web.archive.org/web/20080206082504/http://www.mityc.es/Telecomunicaciones/Secciones/Espectro/cnaf/
  7. ^ a b Israel: "צו הטלגרף האלחוטי (אי תחולת הפקודה) (מס' 2), התשס"ו – 2005" (in hebrew). http://www.moc.gov.il/sip_storage/FILES/3/293.pdf.
  8. ^ a b c Australia: "Radiocommunications (Low Interference Potential Devices) Class Licence 2000". comlaw.gov.au. http://www.comlaw.gov.au/Details/F2009C00545#param6. Retrieved 2011-03-28.
  9. ^ 47 CFR §15.247
  10. ^ "TCB workshop on unlicensed devices". October 2005. p. 58. http://www.fcc.gov/oet/ea/presentations/files/oct05/Unlicensed_Devices_JD.pdf.
  11. ^ NTIA comments to the FCC ET Docket 03-108, footnote 88
  12. ^ http://edocket.access.gpo.gov/cfr_2004/octqtr/pdf/47cfr15.205.pdf
  13. ^ "Cisco Enterprise Mobility 4.1 Design Guide, Chapter 3: WLAN Radio Frequency Design Considerations". p. 3. http://www.cisco.com/en/US/docs/solutions/Enterprise/Mobility/emob41dg/ch3_WLAN.pdf.
  14. ^ IEEE 802.11-2007 Annex J modified by amendments k, y and n.
  15. ^ FCC 15.407 as of June 23, 2011 – hallikainen.com / See paragraph 'h'
  16. ^ a b c d e f g h i FCC Publication - 443999 D01 Approval of DFS UNII Devices v01
  17. ^ Bundesnetzagentur Vfg 7/2010 / See footnote 4 and 5 (german only)
  18. ^ 2005/513/EC: Commission Decision of 11 July 2005 on the harmonised use of radio spectrum in the 5 GHz frequency band for the implementation of wireless access systems
  19. ^ 2007/90/EC: Commission Decision of 12 February 2007 amending Decision 2005/513/EC on the harmonised use of radio spectrum in the 5 GHz frequency band for the implementation of Wireless Access Systems
  20. ^ Information der Obersten Fernmeldebehörde - Drahtlose lokale Netzwerke (WAS, WLAN, RLAN)(german only)
  21. ^ a b Frequency assignments for unlicensed devices / See page 14
  22. ^ a b "Brazil: Resolução nº 506, de 01/07/2008, publicado no Diário Oficial de 07/07/2008, atualizado em 24/11/2010 (in Brazilian Portuguese)". p. 33. http://www.anatel.gov.br/Portal/verificaDocumentos/documento.asp?numeroPublicacao=252315&assuntoPublicacao=null&caminhoRel=Cidadao-Biblioteca-Acervo%20Documental&filtro=1&documentoPath=252315.pdf.
  23. ^ FCC 15.407 as of August 8, 2008 – hallikainen.com
  24. ^ 802.11-2007 Japan MIC Released the new 5 GHz band (W56). Bureau Veritas — ADT. http://www.adt.com.tw/english/news_files/81.pdf. Retrieved 2008-02-23.
  25. ^ "IDA Singapore: Spectrum Management Handbook". May 2011. p. 30. http://www.ida.gov.sg/doc/Policies%20and%20Regulation/Policies_and_Regulation_Level2/20060421164253/SpectrumMgmtHB.pdf.
  26. ^ Korea Frequency Distribution Table 2008.12.31 (in Korean)
  27. ^ KISA MESAFE ERİŞİMLİ TELSİZ CİHAZLARI (KET) YÖNETMELİĞİ Resmi Gazete 10.03.2010 Madde 8 - Genişband veri iletim sistemleri (in Turkish)
  28. ^ a b c "Elimination of interference to Terminal Doppler Weather Radar (TDWR)". http://www.wi-fi.org/files/FCC_Memorandum_on_UNII_Device_Operation_2010_07_27-M.pdf. Retrieved 2012-12-27.
  29. ^ a b c d e "Relating to the use of Short Range Devices (SRD)". ECC. October 9, 2012. http://www.erodocdb.dk/docs/doc98/official/pdf/rec7003e.pdf. Retrieved 2013-02-08.