DECODING OF TRELLIS CODES

摘要

Systems and related methods are described for 1 determining one or more state probabilities for one or more states in a trellis representation 2 or determining an estimate of or extrinsic output for one or more bits using a trellis representation by performing MAXast operations on group of parallel branches of the trellis, performing a MAXast operation involving forward or backward state metrics, and determining said state probabilities or said extrinsic output 3 determining a branch metric for a branch in a trellis representation 4 performing a MAXast 2->1 operation using lookup tables 5 performing a MAXast 2?p¿->1 operation, where p is an integer of two or more, through a hierarchical arrangement of MAXast 2->1 operations and 6 computing forward state probabilities in a forward mode of operation and computing backward state probabilities in a backward mode of operation. Combinations of the foregoing are also described.