5G Downlink Control Channel Puncturing Indication for CBG Retransmission

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Solution Overview

Problem

In 5G wireless communication systems, there is a lack of a definitive method to combine segmented Code Blocks (CBs) into Code Block Groups (CBGs), leading to unnecessary retransmission redundancy and degradation of transmission efficiency, especially when concurrent services like eMBB and URLLC are transmitted, causing punctured data issues that affect the performance of eMBB services.

Innovation Solution

A method is introduced to configure a Transport Block (TB) with a fixed number of CBGs for retransmission, using a downlink control channel with indicating fields to identify punctured data, allowing terminals to determine and handle punctured data within the CBGs, thereby improving transmission efficiency and performance by avoiding the merging of punctured data with retransmitted URLLC data.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If the entire TB is retransmitted in the LTE system, then all CBs can be retransmitted together, but this causes unnecessary retransmission redundancy and degrades transmission efficiency

Engineering Contradiction:
Improvesimplicity of retransmission processVSAvoidtransmission efficiency
Core Design Contradiction:
Ease of manufactureVSProductivity

Solution Approach 1:

The patent divides the Transport Block (TB) into multiple Code Block Groups (CBGs), where each CBG contains one or more Code Blocks (CBs). This segmentation allows selective retransmission of only the failed CBGs rather than retransmitting the entire TB, thereby reducing retransmission redundancy while maintaining manageable complexity through the CBG structure.

Inventive Principle:
Principle #1Segmentation

2Adaptability or versatility

If URLLC service data occupies part of the transport blocks, then URLLC service requirements are met, but the eMBB service data in the overlapping part is punctured and the terminal cannot identify the punctured data

Engineering Contradiction:
Improvesupport for concurrent servicesVSAvoidloss of eMBB service data
Core Design Contradiction:
Adaptability or versatilityVSLoss of information

Solution Approach 1:

The patent introduces a puncturing indication field in the Downlink Control Information (DCI) that provides feedback information to the terminal about which CBGs contain punctured data. This feedback mechanism enables the terminal to identify and handle punctured eMBB service data correctly, preventing erroneous merging with retransmitted URLLC data while maintaining support for concurrent services.

Inventive Principle:
Principle #23Feedback

3Reliability

If the terminal merges retransmitted eMBB service data with previously stored data, then transmission performance should improve, but merging with punctured URLLC data extends errors and degrades performance

Engineering Contradiction:
Improvetransmission reliabilityVSAvoiderror propagation
Core Design Contradiction:
ReliabilityVSLoss of information

Solution Approach 1:

The patent extracts and identifies punctured data segments using the puncturing indication field in DCI. By taking out the punctured CBGs from the retransmission bundle and separately identifying them, the system prevents erroneous merging of punctured URLLC data with eMBB service data, thereby avoiding error propagation while maintaining the ability to merge valid retransmitted data.

Inventive Principle:
Principle #2Taking out (Extraction)

4Productivity

If CBGs are configured for retransmission, then selective retransmission is enabled, but there is currently no definite method for combining CBs into CBGs

Engineering Contradiction:
Improveretransmission efficiencyVSAvoidcomplexity of CBG configuration
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The patent defines a method to segment TBs into CBGs by grouping CBs with consecutive indices. Each TB is divided into multiple CBGs, where the number of CBGs and the distribution of CBs within each CBG are systematically determined. This segmentation approach enables selective CBG-level retransmission while maintaining manageable configuration complexity through regular grouping patterns.

Inventive Principle:
Principle #1Segmentation

Data Source

PatentEP3621234B1Method and device for determining whether data is damaged
Publication Date: 2022.09.21 DATANG MOBILE COMM EQUIP CO LTD
  • EP3621234B1 patent drawingFigure 1~2
  • EP3621234B1 patent drawingFigure 3~4
  • EP3621234B1 patent drawingFigure 5~7

AI summary

Disclosed in an embodiment of the present application are a method and device for determining whether data is damaged, the method comprising: a terminal receiving a downlink control channel which is used for scheduling retransmission; according to the downlink control channel, the terminal determining whether damaged data is present during N previous transmissions of a retransmitted data packet, which are scheduled by the downlink control channel, N being an integer greater than or equal to 1; hence, the terminal receives the downlink control channel which is used for scheduling retransmission, and determines, according to the downlink control channel, whether damaged data is present during the N previous transmissions of the retransmitted data packet, which are scheduled by the downlink control channel, thereby improving transmission performance.