 range of interest. Without belaboring the point, we summarize here the pertinent results (also in the absence of thermal noise) Pb=pPb, (1.103) where Pb, is given by (1.80) with (1.104) The corresponding worst case results are 2.3050 (1.105) 0.1483 favily Eb/NJ 2.3050 -1Q(5x1) Eb/N, < 2.3050 (1.106) where (1.107) Thus far in this chapter, we have focused our entire attention on how aug- menting "ideal" QPSK and QASK with a FH/SS technique allows them to combat a partial-band multitone or noise jammer. The word "ideal" is used here to indicate that although the underlying modulations are so-called "bandwidth efficient" because of the structure of their signal constellations, we have not considered any additional bandwidth conservation produced by transmitter and receiver filtering. Stated another way, we have assumed throughout that the basic transmission pulse is rectangular in shape. In the remainder of this chapter, we examine the detection efficiency of quadra- ture partial response Class I signals in the presence of the identical jamming scenario postulated thus far. Consideration of this form of modulation rep- resents a departure from the basic assumption mentioned above as discussed in the next section. Performance of FH/QPR in the Presence of Partial-Band Multitone Jamming 1.7 PERFORMANCE OF FH/QPR IN THE PRESENCE OF PARTIAL-BAND MULTITONE JAMMING In the design of most digital data transmission systems, the occurrence of intersymbol interference is ordinarily treated as an undesirable phenome- non. Certain signalling systems, however, utilize a controlled amount of inter- symbol interference to achieve certain beneficial effects. These systems have been called, variously, duobinary, polybinary, and partial response [7]- [10]. When such a modulation type is transmitted on quadrature carriers over a common channel, the acronym quadrature partial response (QPR) has been applied. A typical modulator, which generates an FH three-level APR sig- nal,4 is illustrated in Figure 1.17. The transmitted signal in the