characterization for non- coherent FH/MFSK systems. Where possible, exact closed form perfor- mance expressions will be derived; however, in most cases involving coded communication links, exponentially tight upperbounds on Pb will be com- puted in the interest of mathematical expediency. Exact analyses of coded systems generally prove to be intractable, necessitating the use of computer simulations or numerical integrations. While these approaches can generate more accurate results than bounding techniques, they are inconvenient, requiring a new computer calculation whenever even a single system para- meter is changed. Furthermore, the functional dependence of a closed from Ph bound on the various system parameters can provide useful insights into system sensitivity to variations in these parameters. Of course, where simu- lation results are available, comparisons will be made to indicate the accu- racy of our bounds. Our examination of the performance of non-coherent FH/MFSK com- munications begins with uncoded signals received over the familiar additive white Gaussian noise (AWGN) channel. This could represent the situation in which a relatively unsophisticated jammer injects spectrally flat noise over the entire SS bandwidth into the FH receiver, and will be used as a bench- mark against which more intelligent jammers and FH countermeasures can be compared. As in the DS case, we will conservatively adopt the worst case perspec- tive that the jammer has a priori knowledge of all relevant signalling para- meters, with the critical exception of real time PN spreading sequence synchronization. Specifically, a smart jammer is assumed to have the ability to optimize its strategy to exploit information about Wss, M, N, Nb, Rb, Rh, the location of the FH tones and the M-ary bands, the channel code and decoding algorithm, the detection metric, the signal power, and the nominal . Also, reflecting realistic jamming scenarios, we will neglect the received thermal or non-hostile background noise in deference to the typica