Principles of digital data transmision (2nd edition)

A textbook on the principles and techniques of digital data transmission is presented. A nonmathematical survey of the properties of the voice-frequency channels formed by telephone circuits and HF radio links, and of various techniques that have been used or proposed for the transmission of digital data over these channels is given. The different techniques are compared and descriptions are provided of the preferred data transmission systems. A theoretical analysis and comparison of various different signals that may be used for the transmission of digital data is then presented. Both baseband and modulated-carrier signals are studied, with particular emphasis on some of the baseband signals that may be obtained over partial-response channels and by correlative-level coding. Matched filter detection is studied in some detail as is the related topic of the optimum combination of transmitter and receiver filters.