Enhanced decoding and demapping method and apparatus for QAM data signals

US9106470B2 · kind B2 · utility

Assignee

• QUALCOMM Incorporated · US

Inventors

• Lu Zhao · Zhejiang, CN
• Stefan Brueck · Nuremberg, DE
• Stephan Schlupkothen · Aachen, DE
• Muhammad Awais Amin · Nuremberg, DE
• Juan Montojo · San Diego, US
• Marc W. Werner · Nuremberg, DE
• Hendrik Schoeneich · Heroldsberg, DE

Key dates

• Filing date: Jul 19, 2013
• Grant date: Aug 11, 2015
• Expiry date: Jul 19, 2033

Classification

• Technology area (CPC H): Electricity
• CPC primary: H04L1/0036
• WIPO field: Digital communication
• WIPO sector: Electrical engineering

Abstract

A receiver circuit, including a multi-stage QAM de-mapper, for receiving a QAM data signal is disclosed. A first de-mapper circuit recovers a set of encoded data bits from the QAM data signal by calculating a plurality of distances between a received QAM symbol and each of a plurality of possible constellation points. A second de-mapper circuit then generates a set of unencoded data bits for the received QAM symbol based, at least in part, on the plurality of distances calculated by the first de-mapper circuit. The receiver circuit may further include a decoder circuit to decode the set of encoded data bits recovered by the first de-mapper circuit. The second de-mapper circuit may identify a subset of the plurality of possible constellation points based on a result of the decoding and select a constellation point that is associated with the shortest distance of the plurality of distances.