Carrier Aggregation Handover via Segmented Component Carrier Transfer

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

In LTE-A, handover procedures involving carrier aggregation face challenges when the target base station cannot secure an equal number of component carriers, leading to potential communication issues due to delays and difficulties in changing the access destination of specific component carriers.

Innovation Solution

A method for performing handovers by transmitting handover commands for approved component carriers from the source base station to the user equipment, allowing the user equipment to access the target base station for each component carrier, enabling a stepwise handover process that can be completed early for secured carriers, thus avoiding communication delays.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a handover is executed on a communication channel configured with a plurality of component carriers, then the user equipment can maintain communication over multiple frequency bands, but the target base station cannot necessarily secure component carriers which are equal in number to those of the source base station, leading to handover delays

Engineering Contradiction:

Improvecommunication qualityVSAvoidhandover delay

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The handover procedure is segmented into multiple independent handover requests, one for each component carrier. The source base station transmits handover requests for each component carrier separately to the target base station, allowing the target to secure carriers incrementally rather than requiring all carriers to be secured simultaneously, thus reducing handover delay while maintaining communication reliability

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The source base station transmits handover requests for component carriers in advance to the target base station before the handover is fully executed. This preliminary action allows the target base station to prepare and secure component carriers ahead of time, reducing the actual handover execution time and preventing communication delays

Inventive Principle:

Principle #10Preliminary action

2Productivity

If a handover procedure can be carried out for each component carrier, then a handover can be completed early on a number of component carriers which can be secured in the target base station, but the device complexity increases due to multiple handover requests and responses

Engineering Contradiction:

Improvehandover completion speedVSAvoidhandover procedure complexity

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

Multiple handover request responses from the target base station are merged into a single aggregated response that is transmitted back to the source base station. This combining of multiple responses reduces the number of separate signaling messages and simplifies the overall handover procedure complexity while still enabling fast handover completion for each component carrier

Inventive Principle:

Principle #5Merging (Combining)

Data Source

PatentEP2496020B1Method for handover, terminal device, base station, and wireless communication system

Publication Date: 2019.02.27 SONY GROUP CORP

Figure 1
Figure 2
Figure 3A

AI summary

Provided is a method for performing a handover from a first base station to a second base station by a user equipment that is performing a radio communication over a communication channel formed by aggregating a plurality of component carriers. The method includes a step of transmitting a handover command for a component carrier for which a handover has been approved by the second base station among the plurality of component carriers from the first base station to the user equipment and a step of trying to make an access from the user equipment to the second base station for each component carrier in response to the handover command.