Decoding system and method for digital communications

US7173972B2 · kind B2 · utility

Assignee

• Atheros Communications, Inc. · US

Inventors

• John Thomson · Union City, US
• Paul J. Hustad · Corona, US
• Ardavan Maleki Tehrani · Menlo Park, US
• Jeffrey M. Gilbert · Palo Alto, US
• William J. McFarland · Los Altos, US
• Lars E. Thon · San Jose, US
• Yi-Hsiu Wang · Union City, US

Key dates

• Filing date: Mar 23, 2001
• Grant date: Feb 6, 2007
• Expiry date: Dec 29, 2024

Classification

• Technology area (CPC H): Electricity
• CPC primary: H04L27/38
• WIPO field: Basic communication processes
• WIPO sector: Electrical engineering

Abstract

A Viterbi decoding system interprets bits in received QAM constellations as many-valued parameters rather than binary valued parameters. It performs the Viterbi algorithm using these many-valued parameters to provide results superior to hard decision decoding. Rather than applying a hard 0-1 function to the QAM data, the system uses a non-stepped linear or curved transfer function to assign values to the bits. In another aspect, a system differentiates between data bits based on their estimated reliability, giving more emphasis to decoding reliable bits than unreliable bits using any of a variety of techniques. By differentiating between god and bad bits and de-emphasizing or ignoring unreliable bits, the system can provide a significant reduction in uncorrectable errors and packet loss.