ther, the minimum channel PB-FBC would be employed only when its SIN performance advantage over the wideband radiometer justifies its complexity as reflected by the cost of mechanizing the number of channels needed. To further strengthen these earlier conclusions, the performance of these same detectors will now be calculated for several different hop rates and in addition PN spreading of the hop pulses. The results are tabulated in Table 1.5. To repeat an earlier observation, in comparing the S/N° requirements of various intercept detectors, relative to, say, that of the wideband energy detector as a reference, it is not necessary to specify the SS bandwidth Wss, the message duration TM, or the hop rate Rh = 1/T Rather, the product of WSS and TM, the total number of hops NT in W and, if a partial-band con- figuration, the fractional number of channels f used in the implementation are all that are needed to perform the calculations. If PN spreading is used in hybrid with the assumed FH modulation, then one must, in addition, spec- ify the ratio of PN code chip rate R to the hop rate. In Table 1.5 the PN code chip rate is held constant as the hop rate is varied over two decades (the effects of varying the chip rate will be discussed toward the end of this sec- tion). Thus, the ratio RJR also varies over two decades. The central column in Table 1.5 repeats the numbers tabulated in Table 1.3 for FH modulation, with the modification that the time and frequency asynchronous losses derived in Sections 1.2.2.1 and 1.2.2.2, respectively, have been added. All other entries also include losses for lack of time and fre- quency synchronization. A double crosshatched line has been placed to sep- arate the practical versus impractical detector realizations as measured by the number of channels required. As can be seen, only two entries represent a potential gain over the wideband energy detector; these are further reviewed in the following paragraphs. For Rh such that NT = 106, a 125-channel PB-FBC is capable of achieving a lo