4.9 GHz 4.9–5.0 GHz
Table 1-2 clearly shows that not all things are equal, depending on which country you are in.
In Europe, the 2.4-GHz range and the 5.0-GHz range are used. The 5.0-GHz frequency
ranges that are used in Europe are called the Conference of European Post and Telecommu-
nication (CEPT) A, CEPT B, CEPT C, and CEPT C bands. In the United States, the 900-
MHz, 2.4-GHz ISM, and 5.0-GHz Unlicensed National Information Infrastructure (UNII)
bands are used. Japan has its own ranges in the 2.4- and 5.0-GHz range. The following sec-
tions explain the U.S. frequency bands in more detail.
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