However, although the IEEE 802.11a standard specifies WLAN in the 5 GHz UNII (Unlicensed National Information Infrastructure) frequency band, which consists of 3
sub-bands, each with a defined maximum output power: 1-The lower frequency band consists of 4 non-overlapping channels from 5150 to 5250 MHz with a maximum power level of 40 mW; 2-The middle band goes from 5250 to 5350 MHz with a maximum transmit power of 200 mW and also with 4 nonoverlapping channels; 3-The upper frequency band again consists of 4 non-overlapping channels from 5725 to 5825 MHz with a maximum output power of 800 mW.