LDPC Transmitter Incremental Redundancy for Fading Channel Decoding

Solution Overview

Problem

Existing digital broadcasting communication systems face challenges in enhancing reception performance due to errors caused by fading and thermal noise, particularly in wireless channels, where current methods do not effectively utilize incremental redundancy (IR) techniques to improve error correction.

Innovation Solution

A transmitter is designed to process and transmit signals using an incremental redundancy method, employing a low-density parity-check (LDPC) codeword with interleaving and constellation mapping, where parity bits are generated based on specific parity submatrices and cyclic-shifted column groups within a parity check matrix, enhancing error correction capabilities.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If incremental redundancy (IR) method is applied to transmit additional encoded data, then reception success rate is improved, but transmission time and system complexity increase

Engineering Contradiction:

Improvereception success rateVSAvoidtransmission time

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The parity check matrix is segmented into multiple submatrices (first parity submatrix, second parity submatrix, etc.), allowing the encoded data to be divided into multiple transmission batches. The receiver can successfully decode after receiving a portion of the transmitted data, reducing the need to receive all data and improving transmission efficiency

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The transmitter pre-generates multiple sets of parity bits corresponding to different submatrices before transmission. When the receiver needs retransmission, it can directly use the pre-prepared additional parity bits without requiring additional encoding time, thus reducing the impact on transmission time

Inventive Principle:

Principle #10Preliminary action

2Reliability

If incremental redundancy (IR) method is applied to transmit additional encoded data, then reception success rate is improved, but device complexity increases

Engineering Contradiction:

Improvereception success rateVSAvoidsystem complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The parity check matrix is segmented into multiple submatrices (first parity submatrix, second parity submatrix, etc.), allowing the encoded data to be divided into multiple transmission batches. The receiver can successfully decode after receiving a portion of the transmitted data, reducing the need to receive all data and improving transmission efficiency

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different submatrices use different code rates (first code rate for first parity submatrix, second code rate for second parity submatrix, etc.). This parameter variation allows flexible adaptation to different channel conditions while maintaining a unified encoding framework, balancing complexity and performance

Inventive Principle:

Principle #35Parameter changes

3Reliability

If multiple parity submatrices are used to generate first and second parity bits, then error correction capability is improved, but manufacturing precision requirements increase

Engineering Contradiction:

Improveerror correction capabilityVSAvoidprecision requirements

Core Design Contradiction:

ReliabilityVSManufacturing precision

Solution Approach 1:

The parity check matrix is segmented into multiple submatrices (first parity submatrix, second parity submatrix, etc.), allowing the encoded data to be divided into multiple transmission batches. The receiver can successfully decode after receiving a portion of the transmitted data, reducing the need to receive all data and improving transmission efficiency

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different submatrices use different code rates (first code rate for first parity submatrix, second code rate for second parity submatrix, etc.). This parameter variation allows flexible adaptation to different channel conditions while maintaining a unified encoding framework, balancing complexity and performance

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS10263731B2Transmitter and signal processing method thereof

Publication Date: 2019.04.16 SAMSUNG ELECTRONICS CO LTD

AI summary

A transmitter is provided, which includes: an encoder configured to generate a low density parity check (LDPC) codeword comprising information word bits, first parity bits and second parity bits based on a parity check matrix; an interleaver configured to interleave the LDPC codeword; and a constellation mapper configured to map the interleaved LDPC codeword on constellation points, wherein the first parity bits are generated based on one of parity submatrices constituting the parity check matrix and the second parity bits are generated based on another of the parity submatrices constituting the parity check matrix.