Patent ID: 7788572

Claim:
A soft decision value output detector comprising: a plurality of maximum a posteriori (MAP) detectors configured to simultaneously generate state metrics for portions of a sampled data sequence, and to generate soft decision values based on the generated state metrics, wherein each of the MAP detectors comprises: a first MAP unit that is configured to generate the state metrics by a reverse iteration using first and second reverse Viterbi operators and a forward iteration using a first forward Viterbi operator through portions of the sampled data sequence, wherein the first forward Viterbi operator has a different convergence length than the first and second reverse Viterbi operators; and a second MAP unit that is configured to generate the state metrics by a reverse iteration using third and fourth reverse Viterbi operators and a forward iteration using a second forward Viterbi operator through portions of the sampled data sequence, wherein the second forward Viterbi operator has a different convergence length than the third and fourth reverse Viterbi operators.