An introductory treatment of communication theory as applied to the transmission of information-bearing signals with attention given to both analog and digital communications. Chapter 1 reviews basic concepts. Chapters 2 through 4 pertain to the characterization of signals and systems. Chapters 5 through 7 are concerned with transmission of message signals over communication channels. Chapters 8 through 10 deal with noise in analog and digital communications. Each chapter (except chapter 1) begins with introductory remarks and ends with a problem set. Treatment is self-contained with numerous worked-out examples to support the theory. Table of Contents Fourier Analysis. Filtering and Signal Distortion. Spectral Density and Correlation. Digital Coding of Analog Waveforms. Intersymbol Interference and Its Cures. Modulation Techniques. Probability Theory and Random Processes. Noise in Analog Modulation. Optimum Receivers for Data Communication. Appendices. Glossary. References and Bibliography. Answers to Exercises. Index.