Patent ID: 6507927
Filing Date: 2003-01-14
Classification: H03M

Abstract:
A method for estimating the reliability of a decoded data sequence after Viterbi decoding, comprising the steps ofa) corresponding to an initial time instant, establishing the possible initial states for the Viterbi decoding, b) proceeding to a subsequent time instant, c) at each state corresponding to the present time instant, selecting a surviving trellis path among the trellis paths coming into that state and updating a characteristic reliability metric separately in association with each selected surviving trellis path, d) repeating steps b) and c) until a final time instant, and at said final time instant selecting a final surviving trellis path to represent the decoded data sequence, and e) after selecting a final surviving trellis path, converting its characteristic reliability metric to a sequence reliability statistic corresponding to the estimated reliability of the decoded data sequence.