Page 57 - Basics of Electrical, Electronic and Communication

Chapter 17

Advanced communication

Systems

17.1 Introduction

In the chapters 15 and 16, we had a brief review on radio commu-
nication and radar systems. In this chapter, advanced communication
systems such as Microwave communication, Satellite Communication,
Optical communication and Cellular communication systems are dis-
cussed.

17.2 Microwave communication

Microwaves are electromagnetic waves of very short wavelength (in
the order of a few cm). Their frequencies lie in the range 1 GHz
9
to 1000 GHz (1 GHz = 10 Hz). Their short wavelengths make mi-
crowaves ideal for use in radio and television broadcasting. Commu-
nication using microwaves whose wavelengths are very short is called
microwave communication. Microwave communication is a category
of radio communication which deals with radiation of electromagnetic
waves from one point to another through free space. Useful frequency
range for microwave communication lies between 300 MHz and 150

317