Multimedia overlay of frequency hop spread spectrum communication systems
Carl W. Baum, C.C. Growney · 2002
This paper presents and analyzes approaches to overlaying multiple frequency-hop communication systems in a common frequency band. Focus is given to a scenario in which a "high" rate network using multitone signaling or M-ary frequency shift keying (MFSK) overlays a "low" rate network using binary frequency shift keying (BFSK) modulation. Both systems utilize Reed-Solomon coding and interleaving for error control. A key issue is how to best modulate the high rate data so as to maximize the number of users that can reliably operate in both networks. We have shown that if the signal-to-noise ratios are large, multitone modulation schemes allow for many more users than regular MFSK modulation. In lower signal-to-noise-ratio conditions, MFSK is superior. The results suggest that an adaptive approach to modulating the high rate data may be warranted.