When learning to fly my remote controlled helicopter I was also interested in the technical side. In this post I’ll write down what I discovered about the “air interface”.
In most (every?) countries, the use of the electromagnetic spectrum is limited by law. Some frequencies are almost universally reserved for public use (the 2.4GHz band used by e.g. WLANs). Other bands are highly restricted (the band around 120MHz, used for communication with real airplanes). In Belgium, the 35MHz band is reserved exclusively for model aircrafts. Other bands popular around the world are the 40MHz and 72MHz band.