Wi-Fi Radio Frequencies

By international agreement, a section of radio spectrum near 2.4 GHz is reserved for unlicensed industrial, scientific, and medical (ISM) services, including spread spectrum wireless data networks. The 802.11b, 802.11g, and 802.11n services all use this band.

Another band of frequencies near 5.3 GHz is reserved for something called the unlicensed national information infrastructure (U-NII). The Federal Communications Commission (FCC) in the United States and similar regulatory bodies in other countries permit wireless networking in both the ISM band and the U-NII band. 802.11a operates in the U-NII band.

However, the exact frequency allocations for Wi-Fi services are slightly different from one part of the world to another; ...

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