Physical Principles of Radio Communication

Abstract

Electrodynamics is an established science. Ever since James Clerk Maxwell spelled out its fundamental equations in 1865, its tenets have been verified and reverified by measurements, its formalism developed and made more elegant. It is also a science with wide application, since, except for the force of gravity, the vast majority of phenomena with which we come into contact every day is electrical in nature. Light and radiated heat, radio waves of all kinds, X-rays and UV rays are all manifestations of the same basic entity: the electromagnetic wave/photon. The differences between these phenomena stem entirely from different ways in which photons of different wavelength interact with matter.

In conjunction with quantum-mechanical principles, electrical force underlies the structure of atoms and molecules, and therefore all of chemistry, crystallography, and molecular biology as well. Solid and liquid state, all that we perceive as bulk or extension in space, is maintained by a quantum-mechanical balance of electromagnetic forces.

The same electrical force provides a remarkably flexible and efficient method for the transport and distribution of energy, the electric grid. It is the basis of our communication and digital information technology, not to even speak of consumer electronics.