Wireless channels and bands: 2.4, 5 and 6 GHz, channel width, non-overlapping channels, regulatory impacts

Wi-Fi uses unlicensed radio spectrum in three main bands: 2.4 GHz, 5 GHz and, with Wi-Fi 6E and Wi-Fi 7, 6 GHz. Each band is divided into channels, and choosing bands, channels and channel widths well is the biggest single factor in wireless performance. Because Wi-Fi is a shared medium, only one device can transmit on a channel at a time in a given area; every access point and client within hearing range on the same channel has to take turns. Good channel planning is about giving each access point its own clean slice of spectrum.