Performance of MFSK in Simultaneous Partial-Band and Repeat-Back Jamming

Conventional slow-hopped MFSK communications systems exhibit well-understood susceptibilities to partial-band, pulsed, and repeat-back jamming. Error probability can be degraded to inverse rather than exponential dependence on Eb/No unless appropriate diversity, coding, and interleaving are used. Hopping the FSK tones on independent patterns is known to ameliorate repeat-back jamming. In this paper we look at how a system using all these techniques is able to withstand simultaneous repeat-back and partial-band jamming. The result is that when both communicator and jammer optimize their strategies, the combined jamming is no more effective than either technique used separately, even though the jammer has a spectrum of strategies that all achieve the best result.