Method of maximum likelihood decoding with sub-sampled decoding trellis, and corresponding decoding device
US5329537A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 21, 1993 |
| Grant date | Jul 12, 1994 |
| Priority date | — |
| Expiry date | Jan 21, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M13/41
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
Decoding apparatus provides the maximum likelihood decoding of a sequence of samples of the type implementing a Viterbi type of decision algorithm that defines an initial decoding trellis. Sub-sampling apparatus sub-samples the initial trellis by a ratio p to preserve nodes corresponding to one sample out of p consecutive samples. This sub-sampling apparatus associates a p order antecedent node to each preserved node. Trace-back apparatus traces an optimal path back in the sub-sampled trellis by associating the p order antecedent node for each preserved node. The trace back apparatus designates at least the last two nodes of the optimal path. Over-sampling apparatus over-samples the designation of the last two nodes of the optimal path. The factor p is an integer greater than 1 selected so that there is a single path between a node and its p order antecedent in the initial trellis. Hence the bit rate is increased by a factor p, without loss of information.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.