Overview
Read this article from a comprehensive knowledge base, updated and supplemented with articles reviewed by scientific committees.
Read the articleAUTHORS
-
Marc HÉLIER : Engineer from the École supérieure d'électricité - Doctor – Engineer - Professor at Pierre-et-Marie-Curie University
-
Michel NEY : Professor at ENST-Bretagne - Director, Electronics and Telecommunications Systems Laboratory - (LEST) in Brest (University of Western Brittany)
-
Christian PICHOT : Director of Research at the French National Center for Scientific Research (CNRS) - Electronics, Antennas and Telecommunications Laboratory, - University of Nice – Sophia Antipolis
INTRODUCTION
Electromagnetic waves can be emitted into free space by means of an antenna, for example. This is known as free wave propagation, and is widely used for radiotelephone systems, radar or radio communications. However, there are many situations in which it is necessary or more appropriate to transmit this electromagnetic energy in structures generally referred to as "guides". As the name suggests, the electromagnetic wave is transmitted by guided propagation through a mechanism of successive reflections off walls and/or interfaces. At low frequencies, we more commonly speak of wires or cables transmitting electrical signals. This is a simplifying view that allows simple calculation using line theory. However, in all rigor, the dynamic phenomenon is always fundamentally the guiding of an electromagnetic wave.
The guide is the structure linking the generator or its equivalent (which injects the power) and the load at the end of the guide. The latter may be the input to an amplifier, mixer, filter or antenna. It is therefore the key element in the interconnection of devices. Knowing its impedance enables you to adapt the elements connected to it.
Exclusive to subscribers. 97% yet to be discovered!
Already subscribed? Log in!
HF guide structures — Introduction
Features
Article included in this offer
"Electronics"
(
263 articles
)
Updated and enriched with articles validated by our scientific committees
A set of exclusive tools to complement the resources
