The 5 GHz ISM (Industrial, Scientific and Medical) band is a portion of the radio spectrum that is designated by the International Telecommunication Union (ITU) for unlicensed use. The ITU Radio Regulations define this band as ranging from 5725 MHz to 5875 MHz. This band is commonly used for wireless networking applications, such as Wi-Fi, due to its ability to support high data rates. However, it is also shared with other services, such as radar systems, which can cause interference.
The use of lower portions of the 5 GHz band is subject to regulations set by national telecommunications authorities, which, for example in Australia is the Australian Communications and Media Authority (ACMA). Transmitting conditions vary significantly between subsets of the band, with additional conditions imposed to protect the operation of civilian radar, including limiting many of the sub-bands to indoor use.