Patent ID: 6256764
Filing Date: 2001-07-03
Classification: H03M

Abstract:
A method for decoding tailbiting convolutional codes, wherein said tailbiting convolutional codes, which are encoded by a convolutional encoder, include a plurality of encoding states, said method comprising the steps of:assigning an identical first staring score to each of a plurality of encoding states of a tailbiting convolutional code;performing a Viterbi algorithm once on all of said encoding states of said tailbiting convolutional code to associate a first ending score with each of said encoding states;performing said Viterbi algorithm again for each of said encoding states having a first ending score meeting a certain criterion to associate a second ending score with each of said encoding states, wherein the number of encoding states having a first ending score that meets the certain criterion equals the number of times said Viterbi algorithm is performed again; anddecoding said tailbiting convolutional code utilizing a Trellis path having as an initial encoding state one of said encoding states having a lowest second ending score.