tems," Advances in Electronics and Electron Phnysics, vol. 53, pp. 209-267. Sept. 1980. R. L. Pickholtz, D. L. Schilling, and L. B. Milstein, "Theory of spread spectrum communications-a tutorial," IEEE Trans. Commun., COM-30, pp. 855-884, May 1982. [45] N. Krasner, "Optimal detection of digitally modulated signals," IEEE Trans. Commun., COM-30, pp. 885-895, May 1982. [46] C. E. Cook and H. S. Marsh, "An introduction to spread spectrum," IEEE Commun. Mag., vol. 21, pp. 8-16, March 1983. [47] M. Spellman, "A comparison between frequency hopping and direct sequence PN as antijam techniques," IEEE Commun. Mag., vol. 21, pp. 26-33, July 1983. [48] A.B. Glenn, "Low probability of intercept," IEEE Commun. Mag., vol. 21, pp. 26-33, July 1983. Chapter Chapter 2 THE HISTORICAL ORIGINS OF SPREAD-SPECTRUM COMMUNICATIONS "Whuh? Oh," said the missile expert. "I guess I was off base about the jam- ming. Suddenly it seems to me that's SO obvious, it must have been tried and it doesn't work." "Right, it doesn't. That's because the frequency and amplitude of the con- trol pulses make like purest noise-they're genuinely random. So trying to jam them is like trying to jam FM with an AM signal. You hit it SO seldom, you might as well not try." "What do you mean, random? You can't control anything with random noise." The captain thumbed over his shoulder at the Luanae Galaxy. "They can. There's a synchronous generator in the missiles that reproduces the same ran- dom noise, peak by pulse. Once you do that, modulation's no problem. I don't know how they do it. They just do. The Luanae can't explain it; the planetoid developed it." England put his head down almost to the table. "The same random," he whispered from the very edge of sanity. -from "The Pod in the Barrier" by Theodore Sturgeon, in Galaxy, Sept. 1957; reprinted in A Touch of Strange (Doubleday, 1958). Led by the Global Positioning System (GPS) and the Joint Tactical Information Distribution System (JTIDS), the spread-spectrum (SS) concept Major portions of the material in th