Antenna design- Foundations

In the past (XIII ^e century), the term antenna was used to designate a long, slender yard of Latin sails, and from the 18th century onwards, the sensory appendages at the front of the head of certain arthropods. Today, an antenna is a device that converts a guided electromagnetic wave into a spatially radiated electromagnetic wave, and vice versa.

When consulting the literature dedicated to antenna design, we are usually confronted with two types of approach: the first, where we characterize their operation with Maxwell's equations and the help of operators such as the Hertz potential , leads to long and often uninformative calculations. The second, in which antenna characteristics are presented "with your hands" and a few formulas, is more intuitive but limited to specific, often well-known examples, and is difficult to generalize .

In this article, we will build on a unique and rigorous approach to antenna design proposed by Per-Simon Kildal . The aim is to reveal the physical phenomena governing antenna operation through a compact formulation. The aim is to define the set of radiation characteristics that will subsequently be used and developed in other sections on antennas.

For an exhaustive and more academic presentation of the radiation characteristics of antennas, the reader can refer to the following reference , which offers a classic formulation of antenna theory.

The transmission of waves in the environment, and more precisely in the propagation channel, has led to the development...