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Wi-Fi
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Wi-Fi utilizes various channels in the 2.4 and 5.8 GHz band (worldwide), and the 3.6 GHz band (U.S. only). For a list of which channels are available in which regions, refer to the Wikipedia article.
Wi-Fi is a trademark permitted for devices that are based upon a published standard of the IEEE 802.11 committee and that have been certified by the Wi-Fi Alliance. Wi-Fi is presently incorporated in about three billion devices. Wireless cash registers were one of the earliest applications of what is now Wi-Fi.
Wi-Fi devices operate on an unlicensed basis, generally meaning they cannot cause interference to licensed services, and must accept any interference caused to them. Wi-Fi shares bands with other unlicensed or ISM devices, such as cordless phones at 2.4 and 5.8 GHz and microwave ovens at 2.4 GHz.
Some of the key patents related to Wi-Fi are credited (in the courts at least) to the Commonwealth Scientific and Industrial Research Organisation (CSIRO) in Australia, which has collected over $400 million in royalties and legal settlements over patent rights.
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Frequency Bands |
| Band | Use | Service | Table |
| 2400 - 2500 MHz | Wi-Fi (802.11b, 802.11g, 802.11n) | - | - |
| 3655 - 3700 MHz | Wi-Fi (802.11y) (U.S. only) | - | - |
| 4910 - 5845 MHz | Wi-Fi (802.11a, 802.11h, 802.11j, 802.11n) (non-contiguous) | - | - |
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