This text offers a complete and thorough introduction to the analysis and design of digital communication systems. Retaining the broad scope and rigor of the previous edition, the third edition has been updated with a discussion of modern technological advances providing detailed coverage of digital modulation and demodulation techniques, channel coding and decoding, source coding, spread spectrum signals, channel equalization, multiuser communications, and modulation and coding for fading multipath channels. In addition, the book has been carefully reorganized so that each builds on previous material, begins with an introduction to the history and classification of channel models and reviews of important topics in probability and stochastic processes.