t of the Hmin = 29, t = 3 design. Each additional multiplication by A and k2i switch enablement doubles the number of possible FH sequences, and maintains Hmin at 29. When the full generator in Figure 5.19 is employed, any of a set of 1024 period-31 sequences can be generated. The FHMA design of Lempel and Greenberger, based on an m-sequence generator, is in fact a t = 2 Reed-Solomon sequence generator with several elements of the vector adder output disabled. Or equivalently, the Lempel- Greenberger design with J = L is a t = 2 Reed-Solomon sequence genera- tor. In making this comparison, the reader should note that the definitions of q differ in the discussions of these two designs. Both of the sequence sets discussed in this section are generated linearly; hence, the sequences driving the frequency synthesizers have short linear span. Therefore, these designs, while optimal for FHMA applications, are potentially weak when the threat of intelligent jamming exists. 5.9 A LOOK AT THE LITERATURE While we have covered considerable ground in this chapter and presented the fundamentals of PN generator design, much more is available in the open literature. As starting points for literature searches, we refer the reader to Golomb's comprehensive bibliography (406 references) in the revised edi- tion of [12], to the "Cumulative Index 1953-1981," of the IEEE Transactions on Information Theory published with the September 1982 issue (especially papers listed under the headings: sequences, shift register sequences, shift registers, and pseudonoise sequences), and to Sarwate and Pursley's survey article [31] (136 references) on pseudonoise sequences. Also of interest may be Levine's book [51] on cryptographic patents, many being SS related. Additional references on bent sequences [52], spectral analysis of sequences [53], [54], [55], correlation bounds [56], [70], [71], [72], frequency hopping designs [57], [58], [59], [67], [73], [74], [75], [76], balanced sequence sets [92], sequences with large linear span [87], [88], [8