Patent ID: 6094741
Filing Date: 2000-07-25
Classification: H03M

Abstract:
A viterbi decoding apparatus comprising:a decoding processing portion for receiving a punctured convolutional code having an input timing, the input timing of the punctured convolutional code is based on a setting slip state, to decode said punctured convolutional code by a viterbi decoding method thereby to output a viterbi decoding data;a counting means for counting and outputting a decoding error number of said viterbi decoding data; anda synchronous control means for determining one of a plurality of slip states to be said setting slip state in an active state on the basis of said decoding error number, said synchronous control means including:an error-number-by-slip-state calculation means for obtaining respective decoding error numbers of said plurality of slip states from the output of said counting means by sequentially adopting said plurality of slip states as said setting slip state for each of predetermined periods of time, and for calculating decoding error numbers for said plurality of slip states; anda slip state setting means for setting said setting slip state on the basis of a comparison of respective decoding error numbers of said plurality of slip states relative to one another.