The history of mobile radio goes back almost to the origins of radio communication itself. The very early work of Hertz in the 1880s showed that electromagnetic wave propagation was possible in free space and hence demonstrated the practicality of radio communications. In 1892, less than ®ve years later, a paper written by the British scientist Sir William Crookes [1] predicted telegraphic communication over long distances using tuned receiving and transmitting apparatus. Although the ®rst radio message appears to have been transmitted by Oliver Lodge in 1894 [2], it was the entrepreneur Marconi [3] who initially demonstrated the potential of. | The Mobile Radio Propagation Channel. Second Edition. J. D. Parsons Copyright 2000 John Wiley Sons Ltd Print ISBN 0-471-98857-X Online ISBN 0-470-84152-4 Chapter 1 Introduction BACKGROUND The history of mobile radio goes back almost to the origins of radio communication itself. The very early work of Hertz in the 1880s showed that electromagnetic wave propagation was possible in free space and hence demonstrated the practicality of radio communications. In 1892 less than five years later a paper written by the British scientist Sir William Crookes 1 predicted telegraphic communication over long distances using tuned receiving and transmitting apparatus. Although the first radio message appears to have been transmitted by Oliver Lodge in 1894 2 it was the entrepreneur Marconi 3 who initially demonstrated the potential of radio as a powerful means of long-distance communication. In 1895 using two elevated antennas he established a radio link over a distance of a few miles and technological progress thereafter was such that only two years later he succeeded in communicating from The Needles Isle of Wight to a tugboat over a distance of some 18 miles 29 km . Although it seems highly unlikely that Marconi thought of this experiment in terms of mobile radio mobile radio it certainly was. Nowadays the term mobile radio is deemed to embrace almost any situation where the transmitter or receiver is capable of being moved whether it actually moves or not. It therefore encompasses satellite mobile aeromobile and maritime mobile as well as cordless telephones radio paging traditional private mobile radio PMR and cellular systems. Any book which attempted to cover all these areas would have to be very bulky and the present volume will therefore be concerned principally with the latter categories of use which are covered by the generic term land mobile radio . This however is not a book that deals with the systems and techniques that are used in land mobile communications it
