Carrier Aggregation Serving Cell Set Independence for RRC Re-establishment

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Solution Overview

Problem

In carrier aggregation technologies, data transmission is heavily dependent on serving cells, leading to interruptions when a radio link failure occurs, even if other cells with good signal quality are available, resulting in unreliable data transmission.

Innovation Solution

The method involves using a serving cell set with at least two core serving cells that can independently serve the user equipment, and initiating a radio resource control connection re-establishment process only when all core serving cells in the set are unavailable, allowing data transmission to continue using available cells.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If data transmission is heavily dependent on serving cells in carrier aggregation, then the system can maintain long-term competitive advantages and improve spectral efficiency, but data transmission interruption occurs when radio link failure happens even if other cells with good signal quality are available

Engineering Contradiction:
Improvespectral efficiencyVSAvoiddata transmission reliability
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The patent segments the serving cell set into multiple independent core serving cells (at least two), where each core serving cell can independently serve the UE for data transmission. This segmentation allows the system to continue data transmission through available core serving cells even when one experiences radio link failure, thus resolving the contradiction between maintaining high spectral efficiency through carrier aggregation and ensuring data transmission reliability when failures occur.

Inventive Principle:
Principle #1Segmentation

2Reliability

If RRC connection re-establishment process is initiated when radio link failure occurs in master cell, then the system can recover from failure, but data transmission of all services is interrupted

Engineering Contradiction:
Improveconnection recovery capabilityVSAvoiddata transmission interruption time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The patent applies partial action by initiating RRC connection re-establishment process only when all core serving cells are unavailable, rather than when any single cell fails. This selective approach allows data transmission to continue through remaining available core serving cells during partial failures, minimizing data transmission interruption time while still ensuring connection recovery when truly necessary.

Inventive Principle:
Principle #16Partial or excessive action

3Productivity

If all serving cells are used for data transmission, then the system can maximize data transmission capacity, but data transmission of all services is interrupted when one cell fails

Engineering Contradiction:
Improvedata transmission capacityVSAvoiddata transmission continuity
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The patent assigns different roles to different serving cells by designating at least two as core serving cells with independent data transmission capability. This local quality differentiation ensures that not all cells are equally critical - if one core serving cell fails, data transmission can continue through other core serving cells, thus maintaining data transmission continuity while still maximizing overall data transmission capacity through the use of multiple cells.

Inventive Principle:
Principle #3Local quality

Data Source

PatentEP3429271B1Data transmission method and user equipment for RRC re-establishment based on a set of core serving cells
Publication Date: 2022.06.29 HUAWEI TECH CO LTD
  • EP3429271B1 patent drawingFigure 1
  • EP3429271B1 patent drawingFigure 2
  • EP3429271B1 patent drawingFigure 3

AI summary

Embodiments of the present invention provide a data transmission method, user equipment, and an access network device. UE transmits air interface data to an access network device by using a serving cell set including at least two core serving cells that can independently serve the UE to transmit data, and initiates an RRC connection re-establishment process to the access network device only when detecting that all core serving cells in the serving cell set are unavailable. Data transmission is performed by using an available serving cell to the greatest extent. In other words, data transmission can be performed by using any available core serving cell, to reduce the dependence of data transmission between serving cells and minimize possibility of data transmission interruption, thereby improving data transmission robustness.