Link Failure Handling in Dual Connectivity Systems

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In LTE and LTE-Advanced wireless communication systems, user equipment (UE) faces challenges in reporting and handling link failures, such as radio link failures and random access procedure failures, especially when dual connectivity is established with multiple eNBs, leading to unstable communication links and incomplete data transmission.

Innovation Solution

A communication device and method that detects link failures and transmits information about these failures to a master base station, allowing it to reconfigure carriers and prevent future failures by reporting measurement results, including RSRP and RSRQ values, to ensure stable communication.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If dual connectivity is implemented between UE and multiple eNBs, then throughput is improved, but link stability deteriorates due to radio link failures and random access procedure failures

Engineering Contradiction:
ImprovethroughputVSAvoidlink stability
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The patent implements feedback mechanisms where the UE monitors radio link quality and random access procedure status, then reports failure information to the network. The network uses this feedback to identify failed carriers and reconfigure them, creating a closed-loop system that maintains dual connectivity benefits while addressing stability issues through continuous monitoring and adjustment.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The patent introduces dynamic carrier management where the network can reconfigure carriers based on real-time link conditions. When link failures are detected, the system dynamically adjusts the carrier configuration by identifying failed carriers and reconfiguring them through RRC connection reconfiguration messages, allowing the system to adapt to changing wireless conditions while maintaining dual connectivity.

Inventive Principle:
Principle #15Dynamics

2Reliability

If the UE reports detailed failure information to the network, then link failure handling is improved, but device complexity increases

Engineering Contradiction:
Improvefailure handling capabilityVSAvoidfailure detection and reporting complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent segments the failure reporting mechanism into distinct components: physical layer failure detection, RLC layer failure detection, and MAC layer random access failure detection. Each layer independently monitors its specific failure conditions and reports them separately to the network, allowing for granular failure information collection without overwhelming the UE with complex integrated monitoring across all layers simultaneously.

Inventive Principle:
Principle #1Segmentation

Data Source

PatentEP2934057B1Handling link failure in dual connectivity
Publication Date: 2018.06.13 HTC CORP
  • EP2934057B1 patent drawingFigure 1
  • EP2934057B1 patent drawingFigure 2
  • EP2934057B1 patent drawingFigure 3

AI summary

A communication device for handling a link failure in dual connectivity comprises a storage unit for storing instructions and a processing meanscoupled to the storage unit. The processing means is configured to execute the instructions stored in the storage unit. The instructions comprises communicating with a master base station via a first uplink (UL) carrier and a first downlink (DL) carrier;communicating with a secondary base station via a second UL carrier and a second DL carrier; detecting a link failure related to the secondary base station while communicating with the master base station; and transmitting information of the link failure and information of a measurement result related to the secondary base station to the master base station to report the link failure.