The chapter begins with an introduction of spread spectrum systems and discusses certain common application areas. Direct Sequence (DS) spread spectrum system is presented which includes a discussion on how thermal noise and single tone interference affects it. Next, the idea of Code Division Multiple Access (CDMA) is introduced that uses spread spectrum and is useful in multiple access communications. Application of DS spread spectrum in ranging is shown. This is followed by discussion on Frequency Hopping (FH) spread spectrum and its various characteristics. Pseudorandom signal remains an important component in spread spectrum system. Generation and characterization of pseudorandom signal in frequency domain is discussed. Finally, a detailed description of synchronization techniques for both DS and FH systems is given which involves coarse synchronization or acquisition and fine synchronization or tracking.
