 wide area where investments are high, equipment installed in the network networks; packet switching and fast packet switching; video trans- tends to have a relatively long life. The material is advanced, mission. coverage under each topic being detailed. One of the problems of producing a book in a field which is The chapters are all self contained, in the format of a reference changing rapidly is that the material can get out of date. In this I am book, SO the reader can be selective in the material he reads. A grateful to the authors for working to a very tight schedule, to ensure comprehensive contents list and index help in locating a particular that the time lag between the material being written and the publi- topic. Overlap between chapters is kept to a minimum, although it cation of the book could be kept to a minimum. has not been eliminated altogether in order to maintain continuity. The quality of the book is determined by the knowledge and The book is structured into four parts. Part 1 introduces mathe- presentation skills of its authors. The authors who have contributed matical techniques which are required for the analysis of telecom- to the Telecommunications Engineer's Reference book are all spe- munication systems, and which are used subsequently in other cialists in their fields, working in organisations that are in the chapters of the book. forefront of the technology concerned. My thanks to them all for Part 2 deals with the physical environment of telecommunication- producing what, I am sure will be, a major reference book in S. Basic principles are introduced, such as teletraffic theory; electro- telecommunications. magnetic waves; optics and vision; sound, speech and hearing; the ionosphere and the troposphere; and signals and noise. Once again these principles are built on in subsequent chapters. Fraidoon Mazda Part 3 covers fundamental telecommunication topics. Examples Bishop's Stortford are the political and regulatory environment of the telecommunica- February 1993 This page intention