Chapter 1
Antenna Basics
1.1 Introduction
Antennas radiate and receive electromagnetic waves by converting guided waves supported by a guiding structure into radiating waves propagating in free space and vice versa. This function has to be accomplished by fulfilling specific requirements which affect the antenna design in different ways. In general, a number of antennas are installed in a satellite and their requirements vary depending on the application and on the mission. They can be roughly classified into three types: antennas for telemetry, tracking and control (TT&C), high-capacity antennas, and antennas for space instruments or for other specific applications. Several examples of the latter class are reported in the third section of this book.
This chapter provides an overview of the basic antenna parameters and antenna types, and it presents other basic concepts related to the space environment which will introduce the reader to the development of antennas for space applications. Although many basic definitions are presented, the chapter is not intended to provide a comprehensive background to antennas. For this reason, the reader should refer to the extensive literature available on the subject, some of which we list as references.
The chapter is organized as follows. In the first part, the main antenna parameters will be given in accordance with the IEEE Standard ...