Electromagnetics Explained

9 WAVEGUIDES AND SHIELDS

Waveguides and shields may seem like an odd combination for a chapter, but the two actually have a lot in common. The operation of both devices depends on the reflectivity of metals. Metals are highly reflective through most of the electromagnetic spectrum. They reflect radio waves as well as visible light. Although metals have different properties at visible light frequencies, and aren’t conductors in this band, they still reflect most of the incident radiation if the surface is well polished and not tarnished. We take advantage of this whenever we look in the mirror. A mirror is just a piece of glass with a metal film deposited on the backside. The glass serves to protect the metal surface from tarnishing and provides ...