Cell Handover Uplink Grant Coordination for Low Interruption Time

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In 5G mobile communication systems, cell handovers can cause interruption times for terminal devices due to interactions between network devices, and pre-configured uplink grants result in low resource utilization and inflexibility.

Innovation Solution

Network devices negotiate to pre-configure or dynamically configure uplink resources for terminal devices based on specific requests, reducing interruption times and improving resource utilization by synchronizing without random access.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the uplink grant is dynamically configured through interaction between network devices, then the terminal device can access the target cell without random access, but the interaction between network devices increases the interruption time

Engineering Contradiction:
Improvehandover reliabilityVSAvoidinterruption time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The network device pre-configures uplink grant resources for the terminal device before handover occurs. This preliminary configuration stores multiple uplink grant resources with different time-domain positions, allowing the terminal device to immediately use pre-configured resources during handover without waiting for dynamic allocation, thus reducing interruption time while maintaining reliable connectivity

Inventive Principle:
Principle #10Preliminary action

2Loss of time

If the uplink grant is pre-configured for the terminal device, then the interruption time is reduced, but the pre-configured uplink grant cannot be flexibly configured for another terminal device, resulting in low resource utilization

Engineering Contradiction:
Improveinterruption timeVSAvoiduplink resource utilization
Core Design Contradiction:
Loss of timeVSProductivity

Solution Approach 1:

The network device configures uplink grant resources that can serve multiple terminal devices. A single uplink grant resource configuration can be reused by different terminal devices during their respective handover processes. The system maintains a pool of pre-configured uplink grants that can be dynamically allocated to different terminals based on handover needs, making the resources universal and improving overall utilization while keeping interruption time low

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Quantity of substance

If the network device interacts with another network device to provide uplink grant, then the terminal device can obtain uplink resources, but the interaction increases device complexity and processing overhead

Engineering Contradiction:
Improveuplink resource availabilityVSAvoidnetwork device complexity
Core Design Contradiction:
Quantity of substanceVSDevice complexity

Solution Approach 1:

The network device performs preliminary configuration of uplink grant resources in advance, storing multiple pre-configured grants with different time-domain positions. During handover, the terminal device directly uses these pre-configured resources without requiring real-time interaction between network devices. This preliminary preparation reduces both the complexity of inter-device communication and the processing overhead during actual handover operations

Inventive Principle:
Principle #10Preliminary action

Data Source

PatentEP4686258A1Cell handover method and apparatus
Publication Date: 2026.01.28 HUAWEI TECH CO LTD
  • EP4686258A1 patent drawingFigure 1~2
  • EP4686258A1 patent drawingFigure 3~4
  • EP4686258A1 patent drawingFigure 5

AI summary

A cell handover method and an apparatus are provided. A first network device receives a first message or a second message from a second network device, where the first network device provides at least one candidate cell for a first terminal device, the second network device provides a source cell for the first terminal device, the first message is used to request the first network device to provide a first uplink resource of the at least one candidate cell, the second message is used to request the first network device to activate a second uplink resource of the at least one candidate cell, and the first uplink resource and the second uplink resource are used by the first terminal device to access the at least one candidate cell; and sends a third message to the second network device based on the first message, or sends a fourth message to the second network device based on the second message, where the third message includes information about the first uplink resource, and the fourth message indicates that the first network device has activated the second uplink resource. In this way, an interruption time of a terminal device is reduced, and uplink resource utilization of a network device is improved.