What is IEEE 802.11b? - Explained

IEEE 802.11b is an amendment made to the 802.11 wireless networking specification which allows the network technology to extend speed of the transfer rate by using the same legacy frequency protocols 2.4GHz band.


Due to the telecommunication regulations in the most of countries and to allow the general individuals to use the wireless networking, IEEE made the amendments into the 802.11b.

Early 802.11 legacy wireless network was only capable to transfer 1Mbit/s or 2Mbit/s data rate by using the 2.4GHz frequency bands. But the latest update to the 802.11b allowed the wireless networks to transfer at a theoretical speed of 11Mbit/s.

802.11b used the same CSMA/CA media access methods which used in the original standard and in UDP the wireless network was able to achieve 5.9Mbit/s and UDP 7.1Mbit/s practically.

In mid 1999 the products with 802.11b wireless network standard appeared in the commercial markets. 802.11b uses, complementary code keying also known as CCK as the modulation technique. Apple Inc. adopted 802.11b wireless network and launched the Apple iBook with the network capability.

With the 802.11b the true wireless LAN technology started to use rapidly in the general public. Though the speed was higher in the 802.11b wireless networks the interference was an issue that made the users of 802.11b wireless network users suffered. The major interference caused by the code-less phones which were operating via 2.4GHz frequencies, microwave ovens, Bluetooth devices.

2.4GHz Wireless Bands
Illustration showcasing the 2.4GHz frequency Bands. Image by Internet.

There were 14 channels which operated in the 2.4GHz frequency range which was unlicensed to use by the general applications. Below table shows the frequency delta and the center frequency and the channel width of the each network.

Center Frequency
Frequency Delta
Channel Width
Overlaps Channels
Channel IDsNumber of Overlapping Channels
12.412GHz5MHz2.401GHz - 2.423GHZChannel 2 to Chanel 53
22.417GHz5MHz2.406GHz - 2.428GHzChannel 1, Channel 3 to Channel 64
32.422GHz5MHz2.411GHz - 2.433GHzChannel 1 to Channel 2 and Channel 4 to Channel 76
42.427GHz5MHz2.411GHz - 2.438GHzChannel 1 to Channel 3 and Channel 5 to Channel 87
52.432GHz5MHz2.421GHz - 2.443GHzChannel 1 to Channel 4 and Channel 6 to Channel 98
62.437GHz5MHz2.426GHz - 2.448GHzChannel 2 to Channel 5 and Channel 7 to Channel 107
72.442GHz5MHz2.431GHz - 2.453GHzChannel 3 to Channel 6 and Channel 8 to Channel 117
82.447GHz5MHz2.436GHz - 2.458GHzChannel 4 to Channel 7 and Channel 9 to Channel 127
92.452GHz5MHz2.441GHz - 2.463GHzChannel 5 to Channel 8 and Channel 10 to Channel 138
102.457GHz5MHz2.446GHz - 2.468GHzChannel 6 to Channel 9 and Channel 11 to Channel 136
112.462GHz5MHz2.451GHz - 2.473GHzChannel 7 to Channel 10 and Channel 12 to Channel 135
122.467GHz5MHz2.456GHz - 2.478GHzChannel 8 to Channel 11 and Channel 13 to Channel 146
132.472GHz5MHz2.461GHz - 2.483GHzChannel 9 to Channel 12 and Channel 144
142.484GHz12MHz2.473GHz - 2.495GHzChannel 12 to Channel 132