Impact of large Doppler on error performance of FH/MFSK with RS coding in Rayleigh and Rician fading

The degradation of performance caused by Doppler shift to frequency-hopped (FH)/M-ary frequency shift keying (MFSK) Reed-Solomon (RS) coded signal over a Rayleigh and Rician channel is analyzed. The receiver uses a digital processing scheme, consisting of an analog-to-digital (A/D) converter followed by quadrature decomposition and complex-valued envelope discrete Fourier transformation (DFT). Predecoder symbol error probability and postdecoder word error probability are presented as a function of Doppler shift, channel randomness parameter, and the symbol-energy-to-noise ratio. The noise is assumed to be white and Gaussian distributed. Results show that for a typical symbol error rate of 10^-3, the margin for 8-ary uncoded transmission must be increased by 8 dB to account for Doppler in a Rician fading channel