The 3rd edition of this textbook updates its comprehensive coverage of Fourier transform, convolution, and definitions of autocorrelation and power spectral density. This new edition features new chapters on transmission in non-stationary channels and 5G and mobile communications. The authors continue to cover the concepts of probability, random variables, and stochastic processes in full, but brings them up to speed for the modern context. The book features updated information on AM-VSB Modulation, new examples related to new digital television standards, and a revamped chapter on Mobile Cellular Telephony. All major topics including channel modeling, channel characteristics, and propagation are still covered, with an emphasis on simple models. Many updated examples are provided as well as problems at the end of each chapter to allow the reader to practice the acquired knowledge.