The error propagation in the metric computation of the Viterbi Algorithm(VA)constitute one of the major impairment when the signal-to-noise ratio(SNR)is low.A method was proposed to force the VA decoder back to it's initial stage at a fixed time interval.When the decoder is at a known stage,all the stale variables are initialized for further operation.Thus,the error propagation is minimized.In this paper,the BER performance of the modified VA employing trellis coded 8-PSK modulation over wideband mobile radio channel was investigated.Simulation results shows that the BER performance is improved when the SNR is low.
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