Turbo decoder with reduced-size branch metric cache
US7647547B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 2, 2002 |
| Grant date | Jan 12, 2010 |
| Priority date | — |
| Expiry date | Sep 29, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M13/3961
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A method and an apparatus is provided for producing branch metrics in a LogMAP turbo decoding operation. During a forward recursion of a trellis, a set of primary branch metrics is generated. The primary branch metrics are stored in receiver form in a relatively small memory cache module and corresponding secondary branch metrics are produced by negating the primary branch metrics. The primary branch metrics and the secondary branch metrics constitute all possible branch metrics for a given state in the trellis. During a backwards recursion of the trellis, the stored primary branch metrics are retrieved from the memory cache module and the secondary branch metrics are regenerated by negating the retrieved primary branch metrics.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.