초록 ▼

A method for decoding a trellis encoded stream d.sub.k by the use of either an 8 state maximum likelihood response decoding mode through a Gaussian channel or a 16 state partial response decoding mode through a partial response channel is disclosed. In response to a mode selection signal FENA, after

A method for decoding a trellis encoded stream d.sub.k by the use of either an 8 state maximum likelihood response decoding mode through a Gaussian channel or a 16 state partial response decoding mode through a partial response channel is disclosed. In response to a mode selection signal FENA, after passing off the trellis encoded stream for the 8 state mode and removing the influence of a segment synchronization signal from the trellis encoded stream for the 16 state mode, all branch metrics with different values in parallel for either the 8 or the 16 state mode. After selecting a predetermined number of branch metrics required for each state among all the branch metrics of either the 8 or the 16 state mode determined based on the FENA and finding the predetermined number of candidate path metrics and determining a survivor metric and a determination vector thereof, a decoded symbol is determined by tracing back for a decoding depth in response to the FENA based on the determination vector of each state.

대표청구항 ▼

[ What is claimed is:] [11.] An apparatus for decoding a trellis encoded stream d.sub.k by the use of either an 8 state maximum likelihood response decoding mode, in short, an 8 state mode, through a Gaussian channel or a 16 state partial response decoding mode, in short, a 16 state mode, through a

[ What is claimed is:] [11.] An apparatus for decoding a trellis encoded stream d.sub.k by the use of either an 8 state maximum likelihood response decoding mode, in short, an 8 state mode, through a Gaussian channel or a 16 state partial response decoding mode, in short, a 16 state mode, through a partial response channel, wherein the trellis encoded stream d.sub.k is obtained by an M symbol intra-segment interleaving technique using M number of trellis encoders and an index k for identifying a trellis encoded stream generated from a kth trellis encoder among total M trellis encoders is equal to or greater than 1 and equal to or smaller than M, M being a positive integer representing the number of trellis encoders, the apparatus comprising:a segment synchronization signal rejection filter, in response to a mode selection signal FENA, for passing off the trellis encoded stream for the 8 state mode and removing the influence of a segment synchronization signal from the trellis encoded stream for the 16 state mode, thereby generating a filtered trellis encoded stream FILTER.sub.-- OUT;a branch metric unit BMU for calculating branch metrics based on the FILTER.sub.-- OUT for either the 8 or the 16 state mode in response to the FENA;an add-compare-select ACS for selecting a predetermined number of branch metrics required for each state of either the 8 or the 16 state mode determined based on the FENA among the branch metrics fed from the BMU; and adding the selected branch metrics to a predetermined number of previous path metrics to find candidate path metric for each branch metric; and determining a survivor metric and a determination vector thereof, wherein the survivor metric represents a candidate path metric with a maximum likelihood among all candidate path metrics;a path metric network PMN for storing the survivor metric from the ACS for each state and providing the stored survivor metric as a previous path metric for a next previous state to the ACS;a survivor memory unit SMU for storing the determination vector of said each state and tracing back for a decoding depth in response to the FENA based on all determination vectors of all states, thereby finding a decoded symbol;a deinterleaving and output processing unit DOUT for intra-segment deinterleaving the decoded symbol fed from the SMU and converting the intra-segment deinterleaved decoded symbol in the unit of a predetermined size of packet; anda control unit for controlling the segment synchronization rejection filter, the BMU, the ACS, the PMN, the SMU and the DOUT.