Antijam Capability of Frequency-Hop Spread-Spectrum with Reed-Solomon Coding

Abstract

This paper is concerned with increasing the antijam (AJ) capability of frequency-hop spread-spectrum through the use of diversity transmission, Reed-Solomon coding, and a parallel errors and erasures decoding algorithm. The goals are twofold. First it is desirable to increase the jamming margin against a partial-band noise jammer by use of coding and diversity with an efficient error-correction algorithm. Second, it is necessary to totally eliminate the threat of a narrowband jammer (regardless of the jammer's power level) in order to have an effective AJ system. Through an analysis of the effects of partial-band jamming on a frequency-hop spread-spectrum system with diversity, it is shown that the use of Reed-Solomon coding with a parallel errors and erasures decoding algorithm accomplishes these goals. The paper also investigates the accuracy of the Chernoff bound as an approximation to the true performance of a frequency-hop spread-spectrum communication system with diversity, side information, and Reed-Solomon coding. The performance results presented in the paper are exact results based on analysis and computer evaluation and approximate results based on the Chernoff bound. It is shown that the Chernoff bound gives a very poor approximation for many cases of interest.