Error detection/correction and fault detection/recovery – Pulse or data error handling – Digital data error correction
Reexamination Certificate
2008-01-22
2011-12-06
Trimmings, John (Department: 2117)
Error detection/correction and fault detection/recovery
Pulse or data error handling
Digital data error correction
C714S791000, C714S780000, C714S786000, C714S792000, C714S794000, C714S796000
Reexamination Certificate
active
08074157
ABSTRACT:
Methods and apparatus are provided for reduced complexity Soft-Output Viterbi detection. A Soft-Output Viterbi algorithm processes a signal by determining branch metrics using a branch metrics unit; determining survivor paths for sequence detection using a first add-compare select unit; and determining survivor paths for generating one or more bit reliability values using a second add-compare select unit, wherein the first and second add-compare select units process the branch metrics determined by the branch metrics unit. The first and second add-compare select units can optionally process branch metrics having a different number of bits. A sequence detector is provided that comprises a branch metrics unit for determining branch metrics having a first precision; a programmable precision conversion unit for converting the branch metrics having the first precision to branch metrics having a desired precision; and an add-compare select unit for computing path metrics based on the desired precision branch metrics. The Soft-Output Viterbi processor optionally processes a trellis having a reduced number of states relative to a trellis processed by the sequence detector.
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Agere Systems Inc.
Ryan & Mason & Lewis, LLP
Trimmings John
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