TRACE BACK PERFORMING DEVICE IN VITERBI DECODER

摘要

PROBLEM TO BE SOLVED: To obtain the tracing-back performing device in the Viterbi decoder which is low-cost and easily actualized. SOLUTION: At a reverse trace-back part of the Viterbi decoder consisting of a VLSI, a last-in first-out 1 (1400) inputs and stores minimum path values so that a value which is inputted first is outputted last and a value which is inputted last is outputted first. Trace logic 1 (1402) inputs and traces its output and the output of an optimum state detecting means to generate a 1st state, and first-in first-out (1404) inputs and stores the output of the last-in first-out 1 (1400) so that the input which is inputted first is outputted first and the input which is inputted last is outputted last. Trace logic 2 (1406) inputs and traces its output and the 1st state to generate a 2nd state and last-in first-out 2 (1408) inputs and stores the 2nd state so that the first input is outputted last and the last input is outputted first.