NTN Handover Path Switching with Preprocessed Core Network Requests

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In non-terrestrial network (NTN) communication systems, the frequent movement of terminal devices causes large-scale cell handovers, leading to significant processing load and signaling congestion due to the need for rapid cell handovers, which are exacerbated by the large coverage areas of NTN cells and the high speed of non-terrestrial devices.

Innovation Solution

A method where the first access network device sends a path switch request message to the core network device before receiving the handover complete message, allowing the core network to process these requests in advance, thereby reducing handover delays and signaling overheads, using time information to coordinate the handover process.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of time

If the core network device processes path switch requests after receiving handover complete messages, then the processing order is simple and sequential, but handover delay increases and handover efficiency decreases

Engineering Contradiction:
Improvehandover delayVSAvoidprocessing complexity
Core Design Contradiction:
Loss of timeVSDevice complexity

Solution Approach 1:

The core network device receives and processes path switch request messages before receiving handover complete messages. This preliminary processing allows the network to prepare path switch configurations in advance, reducing handover delay when actual handover occurs. The device maintains a buffer to store incoming path switch requests and processes them proactively rather than reactively.

Inventive Principle:
Principle #10Preliminary action

2Reliability

If a large quantity of terminal devices perform cell handover simultaneously due to NTN device movement, then coverage service is maintained, but signaling congestion and processing load increase significantly

Engineering Contradiction:
Improvecommunication service continuityVSAvoidsignaling processing capacity
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The system collects path switch request messages from multiple terminal devices in advance before handover execution. The core network device processes these requests proactively, preparing path switch configurations ahead of time. This reduces the signaling burden during actual handover events, allowing the system to handle large quantities of simultaneous handovers without congestion.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent uses message buffering and replication mechanisms where path switch requests are copied and processed in parallel. The core network device can handle multiple identical or similar path switch requests efficiently by reusing processed configurations, reducing redundant processing load during mass handover scenarios.

Inventive Principle:
Principle #26Copying

3Productivity

If the first access network device waits to send path switch requests until after receiving handover complete messages, then message timing is simplified, but handover efficiency and system responsiveness deteriorate

Engineering Contradiction:
Improvehandover processing efficiencyVSAvoidmessage coordination complexity
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The first access network device sends path switch request messages to the core network device before receiving handover complete messages from terminal devices. This preliminary message transmission allows the core network to start processing path switches early, improving handover efficiency. The access network device manages the complexity of coordinating these early requests through proper message buffering and timing management.

Inventive Principle:
Principle #10Preliminary action

Data Source

PatentEP4697804A1Switching method and apparatus
Publication Date: 2026.02.18 HUAWEI TECH CO LTD
  • EP4697804A1 patent drawingFigure 1~3
  • EP4697804A1 patent drawingFigure 4~5
  • EP4697804A1 patent drawingFigure 6

AI summary

A handover method and an apparatus are provided. The method includes: receiving a handover request message from a second access network device; sending a path switch request message to a core network device; and sending first indication information to the core network device when a handover complete message from a terminal device is received, where the first indication information indicates that the terminal device is handed over to a first access network device, and the path switch request message is sent between receiving the handover request message and receiving the handover complete message. According to the foregoing method, after receiving the handover request message, the first access network device sends the path switch request message to the core network device before receiving the handover complete message, so that the core network device can process the path switch request message in advance, thereby reducing a handover delay caused by processing the path switch request message, and improving handover efficiency of the terminal device.