IAB Relay Handover Sequencing for Parameter-Consistent Mobility

Solution Overview

Problem

Existing handover techniques in Integrated Access and Backhaul (IAB) systems fail to effectively manage handover processing when an IAB node switches connection destinations, leading to potential mismatches in connection parameters and inefficient communication maintenance during mobility.

Innovation Solution

The IAB node withholds transmitting handover control signals to downstream communication apparatuses until a successful handover to a new IAB donor is established, ensuring synchronization and parameter consistency by executing random access processing and completing handover setup before transmitting these signals.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Speed

If the relay apparatus transmits handover control signals to downstream communication apparatuses immediately, then the handover processing speed is improved, but connection parameter mismatches occur between the relay apparatus and downstream apparatuses

Engineering Contradiction:

Improvehandover processing speedVSAvoidconnection parameter consistency

Core Design Contradiction:

SpeedVSReliability

Solution Approach 1:

The relay apparatus performs handover processing to a target base station apparatus before transmitting handover control signals to downstream communication apparatuses. This preliminary action ensures that the relay apparatus has successfully established connection with the target base station, thereby preventing connection parameter mismatches while maintaining efficient handover processing.

Inventive Principle:

Principle #10Preliminary action

2Reliability

If the relay apparatus waits for successful handover before transmitting control signals, then connection parameter consistency is improved, but handover processing time increases

Engineering Contradiction:

Improveconnection parameter consistencyVSAvoidhandover processing time

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The relay apparatus performs handover processing to a target base station apparatus before transmitting handover control signals to downstream communication apparatuses. This preliminary action ensures that the relay apparatus has successfully established connection with the target base station, thereby preventing connection parameter mismatches while maintaining efficient handover processing.

Inventive Principle:

Principle #10Preliminary action

3Reliability

If the relay apparatus performs handover processing before notifying downstream apparatuses, then handover success rate is improved, but processing complexity increases

Engineering Contradiction:

Improvehandover success rateVSAvoidhandover processing complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The relay apparatus performs handover processing to a target base station apparatus before transmitting handover control signals to downstream communication apparatuses. This preliminary action ensures that the relay apparatus has successfully established connection with the target base station, thereby preventing connection parameter mismatches while maintaining efficient handover processing.

Inventive Principle:

Principle #10Preliminary action

Data Source

PatentUS20260107197A1Relay apparatus, communication apparatus, control method, and computer-readable storage medium for executing handover processing of relay apparatus

Publication Date: 2026.04.16 KDDI CORP

AI summary

A relay apparatus that relays communication between a base station apparatus and a communication apparatus that is connected to the base station apparatus executes, in a case where the relay apparatus performs a handover to another base station apparatus, control so as to withhold transmitting/receiving a signal for a handover of the communication apparatus between the communication apparatus and the base station apparatus while the relay apparatus is not successful in a handover.