Convolutional Polar Coding With Smaller List Decoding

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current polar coding methods in communication systems face challenges in reducing implementation complexity and enhancing error correction capabilities, particularly in high-mobility environments, where they often require high computational resources and list sizes that can be inefficient.

Innovation Solution

The implementation of convolutional precoding and decoding of polar codes, which involves using a time-varying puncturing pattern for convolutional codes to reduce list sizes and computational complexity, and employing a convolutional code as an additional layer of protection to provide local error correction and balanced error protection across bit-channels.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional polar coding methods are used, then error correction capability can be maintained, but implementation complexity and list size requirements increase

Engineering Contradiction:
Improveerror correction capabilityVSAvoidimplementation complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent segments the polar code into multiple segments and applies convolutional precoding to each segment independently. This segmentation approach reduces the overall list size required for decoding while maintaining error correction capability, as each segment can be decoded with a smaller list size compared to decoding the entire code block at once.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent introduces convolutional precoding as an intermediary layer between the information bits and the polar encoding process. This intermediary convolutional code provides local error correction capability and balances error distribution across bit-channels, thereby reducing the complexity of the subsequent polar decoding operation while maintaining or improving overall error correction performance.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If larger list sizes are used to improve error correction, then reliability increases, but computational complexity increases

Engineering Contradiction:
Improveerror correction capabilityVSAvoidcomputational complexity
Core Design Contradiction:
ReliabilityVSPower

Solution Approach 1:

The patent applies convolutional precoding in advance before polar encoding to pre-process the information bits and balance error distribution. This preliminary action reduces the burden on the subsequent decoding stage, allowing for smaller list sizes and reduced computational complexity while maintaining error correction capability.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent changes the parameter of list size from large to small by introducing convolutional precoding. The convolutional code modifies the error characteristics of the input data, transforming a problem that would require large list sizes into one that can be solved with smaller lists, thereby reducing computational complexity and power consumption.

Inventive Principle:
Principle #35Parameter changes

3Device complexity

If convolutional precoding is applied, then list size is reduced by at least 50%, but additional encoding steps are required

Engineering Contradiction:
Improvelist sizeVSAvoidencoding throughput
Core Design Contradiction:
Device complexityVSProductivity

Solution Approach 1:

The convolutional precoding process operates on segmented portions of the data stream, allowing for parallel processing and efficient implementation. The segmentation enables the encoding process to be broken down into manageable stages that can be optimized for throughput while achieving the 50% list size reduction.

Inventive Principle:
Principle #1Segmentation

4Reliability

If convolutional precoding with time-varying puncturing pattern is used, then error protection is balanced across bit-channels, but device complexity increases

Engineering Contradiction:
Improveerror protection balanceVSAvoiddevice complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent employs a time-varying puncturing pattern in the convolutional precoding process, where the puncturing pattern changes over time to adapt to different error characteristics of bit-channels. This dynamic approach balances error protection across channels by applying different puncturing rates to different time intervals or code blocks, optimizing reliability while managing complexity through structured variation rather than fully adaptive complex schemes.

Inventive Principle:
Principle #15Dynamics

Data Source

PatentUS11012100B2Convolutional precoding and decoding of polar codes
Publication Date: 2021.05.18 RGT UNIV OF CALIFORNIA
  • US11012100B2 patent drawing
  • US11012100B2 patent drawing
  • US11012100B2 patent drawing

AI summary

Devices, systems and methods for convolutional precoding and decoding of polar codes are disclosed. An example method for error correction in a data processing system includes receiving a noisy codeword, the codeword having been generated based on an outer stream decodable code and an inner polar code and provided to a communication channel or a storage channel prior to reception by the decoder, the stream decodable code characterized by a trellis, and performing, based on the trellis, a list-decoding operation on the noisy codeword vector to generate a plurality of information symbols, the list-decoding operation being configured to traverse through a plurality of states at one or more stages of a plurality of decoding stages.