TABLE OF CONTENTS This background and introduction sets the scene for an appreciation of the issues of mobile communications. The chapter opens with a look at the basic enabling technology for modern, multi user mobile communications, and then gives a glimpse of the extraordinary history of the antennas and how infrastructures have developed. The electromagnetic propagation behaviour and the antenna possibilities emerge as the critical, interconnected issues, and are common to a large variety of mobile and personal communications systems.
To the user, a mobile or personal communications system is simple: it is a terminal, such as a telephone, that uses a radio link instead of a wire link. The visible impact is that the terminal is compact for portability, and that it has an antenna, although for personal communications the antenna is often no longer an explicit feature.
To the communications engineer, however, the user's terminal in a multi user system is one component in a vast, complex, circuit. These circuits are the conduits for voice, data and information access for the users. Three elements are central to realising the circuit of a modern mobile and personal communications system: microelectronic componentry, especially for the portable terminals; the allocation and use of the radio spectrum; and an infrastructure to allow coordination within the communications system.
Microelectronics technologies have allowed sophisticated communications signal processing circuits to become viably miniature and efficient. The functional possibilities and quick design and availability of microelectronic designs have now...
