AN4190 Datasheet, PDF (1/29 Pages) STMicroelectronics – Antenna selection guidelines

AN4190
Application note
Antenna selection guidelines
By Placido De Vita
Introduction
The antenna is a very important component of communication systems. By definition, an
antenna is a device used to transform an RF signal, travelling on a conductor, into an
electromagnetic wave in free space (transmit mode), and to transform an RF
electromagnetic wave into an electrical signal (receive mode).
The choice of antenna is very important for a transmitting - receiving communication
system. The antenna must be able to radiate or receive efficiently so the power supplied is
not wasted.
This application note describes the most important parameters to consider when deciding
what kind of antenna to use in a short range device application.
In the first section of this application note the antenna theory is covered. The main antenna
parameters such as radiation pattern, gain, impedance matching, bandwidth, size and
others are discussed.
In the second part of this document different antenna types are presented.
November 2012
Doc ID 023812 Rev 1
1/29
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