ETSI EN 300 328
The revision of the ETSIEN 300 328 standard places more stringent test requirements on the use of radio frequencies in the license-free ISM band at 2.4 GHz. The ETSI standard is intended to ensure better coexistence of the various radio systems operating in this frequency range. A wide variety of radio systems, transmission methods, transmission powers and modulation types are operated in this frequency range. For example, WLANs according to 802.11, Bluetooth, ZigBee and many others. Some use frequency hopping, others use spread spectrum technology, and still others transmit using classic carrier radio technology.