 of the inter- ference is not known a priori? These are a sample of the questions which must be answered before a real- istic system design can be achieved. Several truths have been demonstrated by this introductory treatment. First, excess bandwidth is required to employ randomized signalling strate- A Spread-Spectrum Overview gies against interference. That is, spreading the spectrum is necessary in this gaming approach to interference rejection. Secondly, if either side, commu- nicator or jammer, fails to completely randomize its signalling strategy, the opponent in principle may observe this fact, adapt to this failing, and take advantage of the situation. Barring this event, the energy gain of the SS sys- tem on the average will be achieved by the communicator unless the jam- mer can avoid complying with a rule of the game. 1.7 REFERENCES In most cases the results of this chapter and the issues raised herein will be fully discussed in greater detail in later chapters. The references listed here are general references to background material, tutorials, and paper collections. 1.7.1 Books on Communication Theory [1] W.B. Davenport, Jr., and W.L. Root, Random Signals and Noise. New York: McGraw-Hill, 1958. [2] D. Middleton, An Introduction to Statistical Communication Theory. New York: McGraw-Hill, 1960. [3] S.W. Golomb, ed., Digital Communications with Space Applications. Englewood Cliffs, NJ: Prentice-Hall, 1964. [4] J. M. Wozencraft and I. M. Jacobs, Principles of Communication Engineering, New York: John Wiley, 1965. [5] M. Schwartz, W. R. Bennett, and S. Stein, Communication Systems and Techniques. New York: McGraw-Hill, 1966. [6] A.J Viterbi, Principles of Coherent Communication. New York: McGraw-Hill, 1966. [7] S. Stein and J.J. Jones, Modern Communication Principles. New York: McGraw- Hill, 1967. [8] H. L. Van Trees, Detection, Estimation, and Modulation Theory (3 vols.). New York: McGraw-Hill, 1968. [9] G. L. Turin, Notes on Digital Communication. New York: Van Nostrand Reinhold, 1969. [10] J.B. Thomas,