Patent · US Expired

Fast space-time decoding using soft demapping with table look-up

US7349496B2 · kind B2 · utility

27Cited by
3References
36Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 27, 2003
Grant dateMar 25, 2008
Priority date
Expiry dateAug 15, 2025

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L2025/03426
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

From potential symbol combinations transmitted from a transmitter, Euclidean distances between the received signals and the symbol vectors are determined in light of the corresponding channel responses and stored in a Euclidean distance table, from which the smallest Euclidean distance is selected as a hard decision. The hard decision is used to find a bit vector corresponding to the estimated symbol vector associated with the hard decision. For each bit in the bit vector, a reduced Euclidean distance table is created to include only Euclidean distances associated with a competing bit associated with the hard decision. The minimum Euclidean distance from each reduced Euclidean distance table becomes a soft demapping decision for a corresponding bit. Log likelihood ratios for each bit are determined by the difference between the hard decision and respective soft demapping decisions. The differences are provided to a channel decoder to recover the originally transmitted bits.

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