Overview

Satellite communication systems are now a major part of most telecommunications networks as well as every-day lives through mobile personal communication systems and broadcast television. A fundamental understanding of such systems is therefore important for a wide range of system designers, engineers and users.

This book is focused on the fundamental principles underlying satellite communication systems, treating each with sufficient depth to provide a balanced overview of the constituent system elements.

Preface

Satellite communication systems are now a major part of most telecommunications networks as well as our every-day lives through mobile personal communication systems and broadcast television. A sound understanding of such systems is therefore important for a wide range of system designers, engineers and users.

This book is focused on the fundamental principles underlying satellite communication systems, treating each with sufficient depth to provide a balanced overview of the constituent system elements. While particular systems are discussed briefly by way of example, detailed descriptions of commercial systems are not included since they are constantly changing and are also described in considerable detail at the system level elsewhere (an excellent coverage of modern systems is given, for example, in Martin, D., Communication Satellites, The Aerospace Press, El Segundo, California, 2000). This book is intended to equip the reader with the sound background knowledge to be able to understand and evaluate such systems. While some familiarity with basic mathematics and communications theory is an advantage, the concepts have been explained at a level that is accessible to a wide range of readers.

There are nine chapters. Chapter 1 provides an introduction to satellite communications, a little history, a description of the space environment, and an outline of basic satellite operation. Chapter 2 addresses the various forms of satellite orbit used for satellite communications and Chapter 3 considers the frequencies used for Earth-space communications as well as a brief discussion of interference issues. Chapter 4 examines propagation with regard to the losses incurred in the uplink and downlink. Chapter 5 discusses the antennas utilised for communications as well as for control of satellite functions. Modulation and multiplexing are the focus of Chapter 6, which describes how baseband signals are translated in frequency to occupy the satellite channel and how signals are combined at the Earth terminal to share the portion of the channel that has been allocated to that station. Since the satellite channel has a very large attenuation and contains channel impairments such as noise, channel coding is the subject of Chapter 7. Chapter 8 then addresses the multiple-access techniques by which geographically separate Earth stations can share the bandwidth available from a satellite transponder. In Chapter 9 we put all these aspects together and consider the link-budget calculations required to make use of a satellite-communications system.

I would like to thank Michael Frater for his comments, as well as for permission to reuse portions of text from our book Communications and Information Systems (Argos Press, 2000). I would also like to thank Andrew Kerans, Christopher Hose and Mark Pickering for their helpful comments.