Conditional Handover With Dual SCG Configurations for CPC States
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In 5G NR systems, the coexistence of conditional handover (CHO) and conditional PSCell change (CPC) configurations leads to invalidation of CHO-DC configurations and double resource reservation, resulting in increased signaling overhead and delayed handover execution.
Innovation Solution
The target secondary node provides two delta SCG configurations: one for before CPC execution and one for after CPC execution, allowing the UE to select the appropriate configuration based on the CPC execution status, ensuring valid handover preparation and resource optimization.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If the target secondary node prepares a single delta SCG configuration for CHO-DC handover, then the handover preparation is simplified, but the configuration becomes invalid when CPC is executed first, leading to handover failure
Solution Approach 1:
The patent divides the single delta SCG configuration into two separate configurations: first delta SCG configuration (for when CPC is not executed) and second delta SCG configuration (for when CPC is executed). This segmentation allows the system to handle different execution scenarios independently, ensuring configuration validity in both cases while maintaining manageable complexity through clear separation of concerns.
Solution Approach 2:
The patent implements dynamic configuration selection where the UE chooses between first and second delta SCG configurations based on whether CPC has been executed. This dynamic approach allows the system to adapt to different execution paths (CPC first or CHO-DC first) rather than using a static single configuration, thereby maintaining reliability across varying operational states.
2Reliability
If the network prepares separate configurations for both CHO-DC and CPC scenarios, then configuration validity is maintained, but signaling overhead increases due to double resource reservation
Solution Approach 1:
The patent merges the resource reservation processes by having the target secondary node prepare both first and second delta SCG configurations in a single preparation operation triggered by the CHO request. Instead of separately reserving resources for CHO-DC and then again for CPC scenarios, the system combines both reservations into one unified process, reducing redundant signaling while ensuring both configurations are valid.
Solution Approach 2:
The patent performs preliminary preparation of both first and second delta SCG configurations before the actual handover execution. By anticipating both possible execution paths (CPC first or CHO-DC first) and preparing appropriate configurations in advance, the system avoids the need for additional signaling and configuration updates during handover execution, thereby reducing overall signaling overhead.
3Extent of automation
If the UE waits for network decision on handover execution, then centralized control is maintained, but handover execution is delayed and prone to failures
Solution Approach 1:
The patent enables the UE to perform preliminary evaluation of execution conditions for both CPC and CHO-DC scenarios before actual handover execution. The UE receives both first and second delta SCG configurations in advance and can independently determine which condition is met first (CPC execution condition or CHO execution condition), allowing rapid execution without waiting for network decision while the network maintains overall control through configuration provision.
Solution Approach 2:
The patent empowers the UE to autonomously decide which handover to execute (CPC or CHO-DC) based on pre-configured conditions and received configurations. The UE self-evaluates execution conditions and self-selects the appropriate configuration without requiring real-time network intervention, thereby reducing execution time while the network maintains control through initial configuration provisioning and condition setting.
Data Source
AI summary
In some examples, a method, performed in a target master node of a radio network, for preparing handover of user equipment, UE, in dual connectivity, DC, where the handover is between respective primary cells, PCells, of a source master node and a target master node, and respective primary secondary cells, PSCells, of a source secondary node and a target secondary node, comprises receiving, from the source master node, a conditional handover, CHO, request message comprising a unique identifier for the UE defined between the source master node and the target secondary node, and an identifier for the target secondary node, transmitting the unique identifier for the UE to the target secondary node as part of an secondary node addition request for CHO with DC preparation; and receiving, from the target secondary node. first and second delta secondary cell group, SCG, configurations, each one of the first and second delta SCG configurations generated whereby to accommodate different CPC execution states.