AirFiber is a Wireless Local Area Network (WLAN) that allows to build wireless network devices without using wires. In Europe, the terms WLAN and Wi-Fi often function as synonyms (Wi-Fi was the name of a product using particular WLAN standard).
The AirFiber network uses microwave or infrared as the transmission medium. It is designed based on the IEEE 802.11 standard, describing the physical and MAC layers. For microwave communication, AirFiber network uses 2.4 GHz band in standards: 802.11, 802.11b, 802.11g, 802.11n, 802.11ac and 802.15.1 (Bluetooth) or 5 GHz in the 802.11a, 802.11n and 802.11ac standards.
In European countries, the 2.4 GHz band includes 13 channels in the range 2400-2483.5 MHz with 5 MHz steps. Each channel has an individual carrier frequency, modulated during data transmission. The band occupied by one network is about 20 MHz, which means in practice that only three networks can work. Otherwise, there will be mutual interference, because the channels overlap each other.