A PCB Designer's Guide to WiFI
Cutting the cord has been a liberating step for we the people. Wireless technology under the aegis of the 802.11 specification that has been around for some time now. So long that the standards body has adopted more protocols than there are letters in the alphabet. One by one, the standards have been improved or regionalized to the point where the newer technology gets two initials instead of just one. For WiFi, 802.11a/b/g/n is a typical combination of different standards while 802.11ac refers to a single standard. That's the one you're likely to find in a new mobile device if there is only one type on board. There's a lot to unpack here so let's get started.
The 802.11abgn standards held court for a while but all things will go obsolete eventually.
Legacy devices use the crowded 2.4 GHz band. It's crowded because anyone can build things that use the frequency range. Microwave ovens were among the first to use it because of the way water molecules get rather excited in the presence of the wavelengths. "Don't watch the food cook". Ovens use a kilowatt or more while wireless uses milliwatts.