List of WLAN channels
channels are frequently accessed using IEEE 802.11 protocols. The 802.11 standard provides several radio frequency bands for use in Wi-Fi communications, each divided into a multitude of frequency channels numbered at 5 MHz spacing between the centre frequency of the channel. The standards allow for channels to be bonded together into wider channels for faster throughput.
860/900 MHz (802.11ah)
operates in sub-gigahertz unlicensed bands. Each world region supports different sub-bands, and the channels number depends on the starting frequency on the sub-band it belongs to. Therefore there is no global channels numbering plan, and the channels numbers are incompatible between world regions.The following sub-bands are defined in the 802.11ah specifications:
| Region | Subband | Bandwidths | Channel count |
| Australia | 915–928 | 1, 2, 4, 8 | 13, 6, 3, 1 |
| China | ' | ' | |
| Europe | 863–868 | 1, | 5, — |
| Europe | 917.4–919.4 | 1 | 2 |
| Japan | 916.5–927.5 | 1 | 11 |
| Korea | 917.5–923.5 | 1, 2, 4 | 6, 3, 1 |
| New Zealand | 915–928 | 1, 2, 4, 8 | 13, 6, 3, 1 |
| Singapore | 866–869 | 1, 2 | 3, 1 |
| Singapore | 920–925 | 1, 2, 4 | 5, 2, 1 |
| Taiwan | ' | ' | |
| United States | 902–928 | 1, 2, 4, 8, 16 | 26, 13, 6, 3, 1 |
| Indonesia | 920-923 | 250 kHz |
2.4 GHz (802.11b/g/n/ax/be)
14 channels are designated in the 2.4 GHz range, spaced 5 MHz apart from each other except for a 12 MHz space before channel 14. The abbreviation F0 designates each channel's fundamental frequency.Interference happens when two networks try to operate in the same band, or when their bands overlap. The two modulation methods used have different characteristics of band usage and therefore occupy different widths:
- The DSSS method used by legacy 802.11 and 802.11b occupies 22 MHz of bandwidth. This is from the 11 MHz chip rate used by the coding system. No guard band is prescribed; the channel definition provides 3 MHz between 1, 6, and 11.
- The OFDM method used by 802.11g and 802.11n occupies a bandwidth of 16.25 MHz. The nameplate bandwidth is set to be 20 MHz, rounding up to a multiple of channel width and providing some guard band for signal to attenuate along the edge of the band. This guardband is mainly used to accommodate older routers with modem chipsets prone to full channel occupancy, as most modern Wi‑Fi routers are not prone to excessive channel occupancy.
As shown in the diagram, bonding two 20 MHz channels to form a 40 MHz channel is permitted in the 2.4 GHz bands. These are generally referred to by the centres of the primary 20 MHz channel and the adjacent secondary 20 MHz channel. The primary 20 MHz channel is used for signalling and backwards compatibility, the secondary is only used when sending data at full speed.
3.65 GHz (802.11y)
Except where noted, all information taken from Annex J of IEEE 802.11y-2008This range is documented as only being allowed as a licensed band in the United States. However, not in the original specification, under newer frequency allocations from the FCC, it falls under the Citizens Broadband Radio Service band. This allows for unlicensed use, under Tier 3 GAA rules, provided that the user doesn't cause harmful interference to Incumbent Access users or Priority Access Licensees and accepts all interference from these users, and also follows all the technical requirements in CFR 47 Part 96 Subpart E.
A 40 MHz band is available from 3655 to 3695 MHz. It may be divided into eight 5 MHz channels, four 10 MHz channels, or two 20 MHz channels.
The division into 5 MHz channels consumes all eight possible channel numbers, and so it is not possible to infer the width of a channel from its number. Instead each wider channel shares its channel number with the 5 MHz channel just above its mid frequency:
- channel 132 can be either 3660-3665 or 3655-3665;
- channel 133 can be either 3665-3670 or 3655-3675;
4.9–5.0 GHz (802.11j) WLAN
In Japan since 2002, 80 MHz of spectrum from 4910 to 4990 MHz has been available for both indoor and outdoor use, once registered.Until 2017, an additional 60 MHz of spectrum from 5030 to 5090 MHz was available for registered use, however it has since been re-purposed and can no longer be used.
50 MHz of spectrum from 4940 to 4990 MHz are in use by public safety entities in the United States. Within this spectrum there are two non-overlapping channels allocated, each 20 MHz wide. The most commonly used channels are 22 and 24.
5 GHz (802.11a/h/n/ac/ax/be)
Country-specific information
DFS and TPC
Source:United States
In 2007, the FCC began requiring that devices operating in the bands of 5.250–5.350 GHz and 5.470–5.725 GHz must employ dynamic frequency selection and transmit power control capabilities. This is to avoid interference with weather-radar and military applications. 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. In FCC parlance, these restrictions are now referred to collectively as the Old Rules. On 10 June 2015, the FCC approved a new ruleset for 5 GHz device operation, which adds 160 and 80 MHz channel identifiers, and re-enables previously prohibited DFS channels, in Publication Number 905462. This FCC publication eliminates the ability for manufacturers to have devices approved or modified under the Old Rules in phases; the New Rules apply in all circumstances as of 2016Source:
United Kingdom
The UK's Ofcom regulations for unlicensed use of the 5 GHz band is similar to Europe, except that DFS is not required for the frequency range 5.725–5.850 GHz and the SRD maximum mean e.i.r.p is 200 mW instead of 25 mW.Additionally, 5.925–6.425 GHz is also available for unlicensed use, as long as it is used indoors with an SRD of 250 mW.
Germany
Germany requires DFS and 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 allowed only for indoor use, leaving only 5.470–5.725 GHz for outdoor and indoor use.Since this is the German implementation of EU Rule 2005/513/EC, similar regulations must be expected throughout the European Union.
European standard EN 301 893 covers 5.15–5.725 GHz operation, and as of 2017 v2.1.1 has been adopted.
6 GHz can now be used.