Question:  I want to use a Tempest 2400 wireless intercom system but want to know if it will interfere / be interfered with an existing 2400 MHz wireless LAN in our building?  Does Tempest require a FCC license to operate in the USA?
Answer:  The 2.4GHz ISM frequency band is a globally accepted portion of the RF spectrum that is available for unlicensed use virtually anywhere, world-wide. In the US the 2.4GHz ISM band is 2400MHz to 2483.5MHz. Elsewhere in the world the band can vary slightly and can go as high as 2495MHz in certain countries. Tempest utilizes up to 80MHz of this spectrum from 2400 to 2480MHz.  Tempest uses frequency hopping spread spectrum technology (FHSS) to hop in this 80MHz section of the band 200 times per second with a narrow band RF signal in comparison to the lower power wide band wireless LAN networks making Tempest immune to most of these signals. 











Regulations governing the use of this band throughout the world require that all devices that operate within the 2.4GHz ISM band use technologies that minimize interference and promote cooperative use of the available spectrum. This allows multiple devices to operate within the band with minimal interference or reduction of range and performance. This means you can pack a whole lot more users into a much smaller RF band while still maintaining a high quality RF link. There is also the added benefit that all of this comes without any complicated, time consuming frequency coordination.