An Abstract Concept like Radio Waves Is Best Illustrated by an Analogy

An abstract concept like radio waves is best illustrated by an analogy. A string can represent some of the characteristics of a radio wave. Hold one side in your hand and raise and lower your hand; a large gentle wave will result. The rise and fall of the jump rope will illustrate the electron’s path as it travels through air. If you raise and lower your hand faster, the wave will move up and down quicker and the wave lengths will not be as wide. This example illustrates radio waves which are analog. Instead of the hand, voltage supplies potential energy for a wave to move up and down; changing voltage will change the frequency of the wave much like increasing the speed of your hand changes the behavior of the string. Current occurs as the energy from raising your arm up and down transfers to energy causing the string to move up and down. In this case the resistance would be the friction caused by the wave moving up and down between the air molecules.

Digital waves are another concept best illustrated by an analogy. They resemble the short, brief, rhythmical beats of a drum. When the drumhead is struck, a burst of sound is released followed by silence. There is a stop and start between each burst unlike the continuous broadcast of the analog signal. Because the signals are not continuous, less energy is required to produce the digital sound. The computer reads these signals as a series of ones and zeroes.

References:

Ciampa, M. (2006). CWNA Guide to Wireless LANs, 2e, Ciampa - © 2006 Thomson Course Technology.