802.11b/g
From http://www.qsl.net/n9zia/dsss-channels.html
See also ChannelList where this has already been documented.
USA/FCC & Canada regions have 11 total channels allocated. All frequencies are in GHz.
Channel |
Lower Frequency |
Central Frequency |
Upper Frequency |
1 |
2.401 |
2.412 |
2.423 |
2 |
2.404 |
2.417 |
2.428 |
3 |
2.411 |
2.422 |
2.433 |
4 |
2.416 |
2.427 |
2.438 |
5 |
2.421 |
2.432 |
2.443 |
6 |
2.426 |
2.437 |
2.448 |
7 |
2.431 |
2.442 |
2.453 |
8 |
2.436 |
2.447 |
2.458 |
9 |
2.441 |
2.452 |
2.463 |
10 |
2.446 |
2.457 |
2.468 |
11 |
2.451 |
2.462 |
2.473 |
http://www.personaltelco.net/~caleb/diagrams/802.11bgchannels.jpg
1,6,11 are the optimal non-overlapping channels. Any channels seperated by at least 5 don't overlap, so if someone is using 3 in a given area, 8 would be the next available non-interfering channel.
802.11.a
For 802.11a, there are 12 non-interfering channels. These are numbered in 5 MHz intervals, so the channel numbers hop by 4s.
Channel |
Frequency |
36 |
5.180 |
40 |
5.200 |
44 |
5.220 |
48 |
5.240 |
52 |
5.260 |
56 |
5.280 |
60 |
5.300 |
64 |
5.320 |
149 |
5.745 |
153 |
5.765 |
157 |
5.785 |
161 |
5.805 |
165 |
5.825 |
These channels are within the "U-NII Band" and are further seperated into three classes:
Frequency Range |
Description |
5.15 - 5.25 |
"Low", max power 50mW, in-building use only, antenna must be integrated |
5.25 - 5.35 |
"Middle", max power 250mW |
5.725 - 5.825 |
"High", max power 1W, for point-to-point outdoor connections |
These classes are defined by the FCC in CFR 47 Part 15 sections 15.205, 15.209, and (Subpart E) 15.401-15.407. You can find this document online if you poke around.
Also, these classes are similarly described in IEEE Std 802.11a-1999, starting on page 25.