Patent · US Expired

Soft output decoder for convolutional codes

US6868132B1 · kind B1 · utility

6Cited by
4References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 10, 2000
Grant dateMar 15, 2005
Priority date
Expiry dateFeb 10, 2020

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03M13/3972
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

Decoding signals represented by a trellis of block length N divided into windows of length L includes a step of decoding a backward recursion from a point P that is after the end of a window back to the end of the window. P is chosen at a sufficient distance from the end of the window such that backward recursion determines a known state metric at the end of the window. A next step includes decoding the window using backward recursion from the known state at the end of the window back to the beginning of the window to define a set of known backward recursion state metrics which are stored. A next step includes decoding using forward recursion starting from a known state at the beginning of the window and moving forward. A next step includes calculating a soft output at each stage of the forward recursion using the stored backward recursion state metrics, and branch metrics at each stage, and outputting the soft output for that stage.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.