Frequencies and Channels

Let us look a bit closer at how the 2.4GHz band is used in 802.11b. The spectrum is divided into evenly sized pieces distributed over the band as individual channels. Note that channels are 22MHz wide, but are only separated by 5MHz. This means that adjacent channels overlap, and can interfere with each other. This is represented visually in Figure 2.4.

Figure 2.4: Channels and center frequencies for 802.11b. Note that channels 1, 6, and 11 do not overlap.

For a complete list of channels and their center frequencies for 802.11b/g and 802.11a, see Appendix B.