Sidelink Relay SIB Forwarding for Targeted System Information Updates

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing wireless communication systems face challenges in efficiently delivering system information updates to remote UEs, particularly those in RRC_IDLE or RRC_INACTIVE states, or out-of-coverage, through sidelink relay operations.

Innovation Solution

A relay UE maintains a list of interested system information block (SIB) types for remote UEs and forwards only the relevant updates via sidelink connections, using PC5 radio resource control messages, thereby avoiding unnecessary signaling over access links.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of information

If the relay UE forwards all updated SIBs to remote UEs, then the remote UEs receive complete system information, but the signaling overhead increases and efficiency decreases

Engineering Contradiction:
Improvesystem information delivery completenessVSAvoidsignaling efficiency
Core Design Contradiction:
Loss of informationVSProductivity

Solution Approach 1:

The relay UE extracts and forwards only the specific SIB types that remote UEs are interested in, rather than forwarding all updated SIBs. This is achieved by maintaining a list of interested SIB types for each remote UE and selectively forwarding only those SIBs that match the interested types, thereby reducing signaling overhead while delivering complete relevant information.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The relay UE applies different forwarding behavior to different remote UEs based on their individual interests. By maintaining separate lists of interested SIB types for each remote UE and customizing the forwarding content accordingly, the system achieves local optimization where each remote UE receives exactly the information it needs without unnecessary overhead.

Inventive Principle:
Principle #3Local quality

2Productivity

If the relay UE maintains detailed lists of interested SIB types for multiple remote UEs, then the information delivery becomes more efficient and targeted, but the device complexity increases

Engineering Contradiction:
Improveinformation delivery efficiencyVSAvoidrelay UE processing complexity
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The relay UE uses a universal data structure (list of interested SIB types) that can serve multiple remote UEs with different information needs. This list structure is maintained within the remote UE context and can be efficiently updated and queried, allowing the same mechanism to handle diverse information delivery requirements without requiring separate complex processing for each remote UE.

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

3Adaptability or versatility

If the relay UE acquires all updated SIBs from the network, then it can forward any requested SIB to remote UEs, but the acquisition overhead and energy consumption increase

Engineering Contradiction:
ImproveSIB forwarding flexibilityVSAvoidrelay UE energy consumption
Core Design Contradiction:
Adaptability or versatilityVSUse of energy by moving object

Solution Approach 1:

The relay UE extracts only the specific SIB types that are actually needed by remote UEs (as indicated in the interested SIB types list) rather than acquiring all updated SIBs from the network. This selective acquisition approach maintains the ability to forward requested SIBs while significantly reducing the acquisition overhead and energy consumption by focusing only on relevant information.

Inventive Principle:
Principle #2Taking out (Extraction)

Data Source

PatentEP4171163B1Methods and apparatus of si acquisition for sidelink relay operation
Publication Date: 2026.02.11 MEDIATEK SINGAPORE PTE LTD
  • EP4171163B1 patent drawingFigure 1
  • EP4171163B1 patent drawingFigure 2~3A
  • EP4171163B1 patent drawingFigure 3B~4

AI summary

Apparatus and methods are provided for system information delivery through a sidelink relay in a wireless network. In one novel aspect, the relay UE obtains and maintains a list of interested system information block, SIB, types of the remote UE, acquires the updated SI/SIBs, and forwards the updated SIBs that the remote UE is interested in. In one embodiment, the UE establishes a sidelink connection with a remote UE (601), obtains a list of interested SIB types of the remote UE (602), receives a short message from the wireless network (603), acquires updated SIBs (604), and forwards one or more selected SIBs based on the list of interested SIB types to the remote UE (605). In another embodiment, the relay UE stores/maintains the list of interested SIB types of the remote UE within a remote UE context of the remote UE during the lifetime of the remote UE.