Optimization of a hybrid SFH/DS MFSK link with nonoverlapping FH slots in the presence of worst case multitone jamming

The performance of a hybrid slow-frequency-hopped direct-sequence multiple-frequency shift-keyed (SFH/DS MFSK) communication link in the presence of partial band multitone jamming is considered. The communication signal is characterized by a DS-spread MFSK signal bandwidth equal to the FH slot spacing, and the signal consists of many M-ary symbols per DS code period. An equation for the bit error rate (BER) is derived for the signal versus a jammer made up of equally spaced randomly phased tones. The susceptibility to jamming is shown to be a function of three interdependent parameters that contribute to the total signal bandwidth: the numbers of baseband modulation levels M , the number of FH slots, and the DS spreading factor. For a fixed total bandwidth, a tradeoff analysis of these three parameters is performed to determine the optimal system configuration. The system design that gives the best antijam performance is shown to be one in which M and the DS spreading factor are maximized at the expense of the number of FH slots