Radio Link Control Sequence Number Segmentation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In communication systems, particularly in LTE Advanced, there is a challenge in efficiently managing sequence numbers for data units across multiple component carriers to minimize latency and optimize data conveyance, especially during initial transmissions and retransmissions, due to limitations in sequence number space and potential acknowledgement errors.

Innovation Solution

Assigning a sequence number to a data unit and forming segments from it, with each segment retaining the same sequence number, which are then conveyed using one or more component carriers, allowing for efficient data conveyance and retransmissions across different carriers, thereby optimizing sequence number space usage and reducing latency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If sequence numbers are assigned to each data unit and segments are formed with unique sequence numbers, then data transmission reliability is improved, but sequence number space is consumed faster leading to increased latency

Engineering Contradiction:
Improvedata transmission reliabilityVSAvoidlatency
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The patent segments a data unit into multiple segments, where each segment is assigned the same sequence number as the original data unit. This segmentation allows parallel transmission of segments across multiple component carriers without consuming additional sequence numbers, thereby maintaining transmission reliability while reducing latency.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent introduces a new dimension for identifying segments by using segment offsets in addition to sequence numbers. This dimensional extension allows the system to track and manage multiple segments of the same data unit without expanding the sequence number space, thus solving the contradiction between reliability and latency.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Speed

If multiple component carriers are used for data conveyance, then data transmission speed is improved, but sequence number management complexity increases

Engineering Contradiction:
Improvedata transmission speedVSAvoidsequence number management complexity
Core Design Contradiction:
SpeedVSDevice complexity

Solution Approach 1:

The patent segments data units into multiple segments that can be transmitted in parallel across multiple component carriers. Each segment carries the same sequence number as the original data unit, allowing the receiver to reassemble segments without complex sequence number management, thus maintaining high transmission speed while simplifying management complexity.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent introduces segment offsets as an intermediary parameter that mediates between multiple component carriers and the sequence number management system. This intermediary allows segments to be identified and tracked across multiple carriers without requiring complex sequence number assignments, reducing management complexity while maintaining transmission speed.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Quantity of substance

If sequence numbers are reused for segments of the same data unit, then sequence number space usage is optimized, but acknowledgement error rate increases

Engineering Contradiction:
Improvesequence number space usageVSAvoidacknowledgement accuracy
Core Design Contradiction:
Quantity of substanceVSReliability

Solution Approach 1:

The patent segments data units while reusing the same sequence number for all segments of a given data unit. This segmentation approach optimizes sequence number space usage by allowing reuse, while the segment offset parameter enables accurate tracking and acknowledgment of each segment, preventing acknowledgement errors despite sequence number reuse.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent introduces segment offsets as an intermediary mechanism that resolves the conflict between sequence number reuse and acknowledgment accuracy. The segment offset uniquely identifies each segment within a data unit, allowing the receiver to correctly acknowledge each segment even when sequence numbers are reused, thus maintaining both sequence number space efficiency and acknowledgment accuracy.

Inventive Principle:
Principle #24Intermediary (Mediator)

Data Source

PatentEP2676476B1Radio link control
Publication Date: 2018.10.31 NOKIA SOLUTIONS & NETWORKS OY
  • EP2676476B1 patent drawingFigure 1~3
  • EP2676476B1 patent drawingFigure 2

AI summary

The invention relates to apparatuses, methods, a system, computer programs, computer program products and computer-readable media.