What is propagation, multipath, and fading?
Propagation Electromagnetic wave propagation describes how a wave gets from one point to another depending upon the environmental conditions it encounters along the way. For example, a low frequency wave that encounters a plaster wall will likely travel through it. On the other hand, a much higher frequency wave will bounce off the wall. And a wave of an intermediate frequency might bounce off the wall but lose a substantial amount of energy in the process. It is apparent that propagation can have severe effects on the received signal. Multipath In a typical wireless environment, no direct line-of-sight (LOS) path between the transmitter and the receiver exists. In fact, the electromagnetic waves emitted by the transmitter usually take different paths to get to the receiver, depending upon the obstacles in the environment. As a result, the received signal comprises a sum of the various contributions, each of which differs in both amplitude and phase. In many cases, the signals combine
