Sidelink TDOA Positioning With Anchor UE Synchronization

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing positioning methods in 3GPP LTE and NR systems lack the precision required for accurate UE synchronization, particularly in scenarios requiring enhanced mobile broadband, massive machine-type-communications, and ultra-reliable low latency communications.

Innovation Solution

Enhances anchor UE synchronization to improve positioning accuracy through advanced synchronization techniques, such as SL-TDOA positioning, utilizing multiple base stations and direct UE-to-UE communication.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If existing positioning methods in 3GPP LTE and NR systems are used, then positioning functionality is provided, but positioning accuracy and UE synchronization precision are insufficient

Engineering Contradiction:
Improvepositioning accuracyVSAvoidsynchronization precision
Core Design Contradiction:
Measurement precisionVSReliability

Solution Approach 1:

The patent introduces a location management function (LMF) as an intermediary entity that coordinates positioning between multiple UEs and base stations. The LMF manages positioning sessions, determines anchor UEs, and processes positioning information, thereby improving synchronization precision and positioning accuracy through centralized control and coordination of the positioning process

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent segments the positioning system into distinct functional components: anchor UEs that provide reference signals, target UEs that receive positioning services, and base stations that facilitate communication. This segmentation allows each component to be optimized for its specific function, improving overall positioning accuracy and synchronization precision

Inventive Principle:
Principle #1Segmentation

2Measurement precision

If anchor UE synchronization is improved through advanced techniques, then positioning accuracy increases, but system complexity increases

Engineering Contradiction:
Improvepositioning accuracyVSAvoidsynchronization system complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent makes existing UEs and base stations multi-functional by enabling UEs to operate as anchor UEs for positioning purposes while maintaining their normal communication functions. Base stations serve both regular data transmission and positioning coordination roles. This universal approach improves positioning accuracy without requiring entirely new specialized devices, thereby limiting the increase in system complexity

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

3Measurement precision

If multiple base stations and direct UE-to-UE communication are utilized for SL-TDOA positioning, then positioning precision improves, but communication overhead and processing requirements increase

Engineering Contradiction:
Improvepositioning precisionVSAvoidcommunication overhead
Core Design Contradiction:
Measurement precisionVSQuantity of substance

Solution Approach 1:

The patent extracts and separates positioning-related signaling from general communication traffic by introducing dedicated positioning reference signals (PRS) and specific positioning information elements. This extraction allows positioning data to be handled independently, improving positioning precision while managing communication overhead through dedicated resource allocation rather than mixing with general data traffic

Inventive Principle:
Principle #2Taking out (Extraction)

Data Source

PatentEP4694426A1Sidelink positioning method
Publication Date: 2026.02.11 LG ELECTRONICS INC
  • EP4694426A1 patent drawingFigure 1
  • EP4694426A1 patent drawingFigure 2
  • EP4694426A1 patent drawingFigure 3

AI summary

One disclosure of the present specification provides a method for an anchor UE performing communication. The method comprises the steps of: performing synchronization through a specific synchronization source; determining the distance between the specific synchronization source and the anchor UE; and, on the basis of the determined distance, performing sidelink-based time difference of arrival (TDOA) for the positioning of a target UE.