The concept of antenna aperture is perhaps the most important antenna specification that is often misunderstood. Many commonly published equations for radio engineers rely upon antenna equations that employ aperture but never explain the fundamentals, they simply give the equations and leave it at that. In addition, two other selected topics will be presented: antenna radiation resistance and the mechanism of antenna radiation.
The purpose of this brief overview is to explain these concepts. Virtually all advanced texts on antenna theory explain these topics in detail, since their goal is to provide deep understanding of the subject. This is an attempt to provide an empirical fundamental understanding while providing the key equations of these often misunderstood topics.