Writing a comprehensive book on satellite communications requires the com mand of many technical disciplines and the availability of up-to-date information on international recommendations, system architectures, and equipment stand ards. It is therefore necessary to involve many authors, each possessing a good level of knowledge in a particular discipline. The problem of using a coherent and unambiguous set of definitions and basic terms has been solved by including in the book all the background information needed for understanding satellite communication systems, without any major reference to other textbooks specializing in particular disciplines. The obvious consequence of this approach has been the large size of the book, with the advantages, ho...