Optimum Reed-Solamon codes for M-ary FSK modulation with hard decision decoding in Rician-fading channels

M-ary frequency shift keying (MFSK) is a power-efficient modulation method that is useful for low power and low data rate applications. The power efficiency of this modulation method increases as the signal alphabet increases at the expense of increased complexity and reduced bandwidth efficiency. We present an analysis of its uncoded and coded performance in Rician-fading channels using noncoherent demodulation with Reed-Solomon (RS) codes and hard decision decoding. Previous numerical difficulties encountered in determining the performance of large alphabet sizes are circumvented by the analysis presented, and the results obtained are used to quantify performance gains that can be realized by expanding the modulation's alphabet size. Optimum RS codes for hard decision decoding are determined using bit error probability as performance measure for a wide range of Rician channel parameters. The results of this paper should be useful as benchmarks of obtainable performance and as a reference for validating the results of simulation studies.