Why are raidowaves used for Wifi and Bluetooth but microwaves for satellite communication among other things. I was under the assumption that radiowaves are used for communication only. What are the factors which play into this decision. Also, is there a link between frequency of a wave and the amount of information it can carry? Also, can electromagnetic waves take the form of analogue signals and how does this work exactly? Creating analogue and digital signals in terms of the electromagnetic wave produced.