TABLE OF CONTENTS This section covers the scientific principles that make wireless communication possible. Radio components and their associated frequency range is the primary mode of transmission in the wireless industry.
Radio is the wireless transmission and reception of electric impulses or signals by means of EM waves. EM waves are present at all frequencies; however, currently only a small part of this total spectrum can be utilized to transmit communication signals. This small subset of frequencies is commonly referred to as the RF spectrum and ranges from approximately 9 kilohertz (KHz) to 300 gigahertz (GHz). When designing a wireless network, understanding the science behind wireless communication allows you to recognize potential complications such as signal-to-noise (S/N) ratio, attenuation and multipath scattering, and channel spacing.
This section also explores the basic science of EM waves, and how and why radio signals are modulated onto carrier waves. It explores antenna design, the relationship between wave propagation technologies and signal power, and what elements make up a wireless network.
The German scientist Heinrich Hertz demonstrated in 1887 that electrical energy could be transmitted through space by way of EM waves. Even though Professor Hertz was the first to demonstrate this phenomenon, he did not grasp the impact of his discovery. It took the work of Nikola Tesla and Guglielmo Marconi, who were inspired to use Hertz s discovery to transmit signals thus, the first radio was born.
Electric fields are induced by the separation of...
