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There are several uses of the 2.4 GHz band. Interference may occur between devices operating at 2.4 GHz. This article details the different users of the 2.4 GHz band, how they cause interference to other users and how they are prone to interference from other users. ==Phone== Many cordless telephones and baby monitors in the United States and Canada use the 2.4 GHz frequency, the same frequency at which Wi-Fi standards 802.11b, 802.11g and 802.11n operate. This can cause a significant decrease in speed, or sometimes the total blocking of the Wi-Fi signal when a conversation on the phone takes place. There are several ways to avoid this however, some simple, and some more complicated. * Using wired phones, which do not transmit. * Using cordless phones that do not use the 2.4 GHz band. * Using the 5 GHz band. *DECT 6.0 (1.9 GHz), 5.8 GHz or 900 MHz phones, commonly available today, do not use the 2.4 GHz band and thus do not interfere. *VoIP/Wi-Fi phones share the Wi-Fi base stations and participate in the Wi-Fi contention protocols. *Several different Wi-Fi channels are available and it is possible to avoid the phone channels. The last will sometimes not be successful, as numerous cordless phones use a feature called Digital Spread Spectrum. This technology was designed to ward off eavesdroppers, but the phone will change channels at random, leaving no Wi-Fi channel safe from phone interference. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「List of 2.4 GHz radio use」の詳細全文を読む スポンサード リンク
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