Conditional Fallback Configuration for MCG-RLF in Dual Connectivity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current communication systems face challenges in handling master cell group radio link failures during dual connectivity, leading to service disruptions and high latency due to the need for RRC re-establishment, which is costly and time-consuming.
Innovation Solution
Implementing a conditional fallback configuration linked to a master cell group radio link failure event, allowing for immediate handover from the master network node to a secondary network node without requiring RRC reconnection, thereby avoiding service disruptions and reducing latency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If RRC re-establishment is performed after master cell group radio link failure, then connection reliability is restored, but service disruption time increases and latency increases
Solution Approach 1:
The patent applies preliminary action by pre-configuring fallback configurations (including secondary cell group configurations and candidate target master node information) before radio link failure occurs. When MCG-RLF happens, the UE can immediately execute the pre-prepared fallback configuration without waiting for RRC re-establishment procedures, thus reducing service disruption time while maintaining connection reliability.
2Reliability
If RRC re-establishment procedure is initiated, then connection is restored, but signaling overhead increases and processing complexity increases
Solution Approach 1:
The patent extracts the essential handover functionality from the complex RRC re-establishment procedure. By implementing conditional handover with pre-configured fallback configurations, the solution removes the need for extensive RRC re-establishment signaling exchanges between UE and network, reducing signaling overhead and processing complexity while maintaining connection restoration capability.
3Loss of time
If immediate handover without RRC reconnection is implemented, then service disruption is minimized, but handover reliability may be compromised
Solution Approach 1:
The patent uses preliminary action by pre-configuring multiple candidate target master nodes and their associated parameters (such as synchronization signal block information, random access resources) before handover is needed. This allows the UE to perform reliable handover to a pre-validated target node immediately upon failure, ensuring both speed and reliability.
Solution Approach 2:
The patent applies beforehand cushioning by preparing backup fallback configurations with multiple candidate target nodes. If the primary fallback target is unavailable or unsuitable, the UE has pre-configured alternative targets to switch to, ensuring handover reliability is maintained even in challenging radio conditions.
Data Source
AI summary
Improved techniques of handover involving dual connectivity configuration with CHO include configuring a UE with a conditional fallback configuration (CFC) linked to M-RLF event at the source MN. Specifically, the MN prepares a fallback configuration along with the CHO configuration for the UE. This fallback configuration is provided to the UE as a conditional configuration, but this is not linked to measurement-event but rather to a radio link failure event. The condition is linked to MCG-RLF along with additional measurement criteria.