The effect of multiple-tone interfering signals on a direct sequence spread spectrum communication system

The present investigation is concerned with the performance of direct sequence spread spectrum systems operating in the presence of tone interferers or jammers. The Chernoff bounding technique is used to provide an upper bound to the average probability of error of a direct sequence spread spectrum communication system operating in the presence of multiple tone jammers. At low error rates the bound appears to be within approximately 1 dB of the true probability of error. Numerical results are presented which indicate, among other things, the extreme sensitivity of the system to the frequency locations of the jammers. Also presented is an approximation to the average probability of error for the special case of a single jammer whose frequency equals, under certain conditions, the carrier frequency of the transmitted signal.