MAC Control Element Signaling for GNSS Validity Sharing in IoT

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Solution Overview

Problem

Existing IoT terminal devices do not support simultaneous GNSS receiving and LTE transmitting and receiving, leading to challenges in sharing and synchronizing GNSS validity duration, which affects the accuracy and effectiveness of GNSS positioning.

Innovation Solution

A method is proposed where a first MAC control element (CE) carries the GNSS validity duration, enabling accurate sharing between the terminal device and the network device.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If the terminal device reports the GNSS validity duration, then the network device can obtain accurate positioning information, but there is no clear solution on how to report the GNSS validity duration

Engineering Contradiction:
Improvepositioning accuracyVSAvoidreporting mechanism complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The MAC CE is designed to serve multiple purposes: it carries both uplink data and the GNSS validity duration information in a unified structure. This multi-functional approach eliminates the need for separate reporting mechanisms, resolving the contradiction by providing a clear reporting solution while maintaining system simplicity

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

Solution Approach 2:

The MAC CE acts as an intermediary carrier that bridges the terminal device and network device for information exchange. It mediates the transmission of GNSS validity duration information, providing a clear and standardized reporting path without adding complex reporting infrastructure

Inventive Principle:
Principle #24Intermediary (Mediator)

2Measurement precision

If the terminal device obtains GNSS position fix, then accurate positioning is achieved, but the GNSS position fix has a validity duration that expires and requires re-obtaining

Engineering Contradiction:
Improvepositioning accuracyVSAvoidtime for re-obtaining position fix
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The terminal device calculates and reports the GNSS validity duration in advance before the position fix expires. This preliminary action allows the network device to proactively manage the positioning information lifecycle, triggering re-acquisition procedures before accuracy degrades, thus reducing the time loss from expired position fixes

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system establishes a feedback loop where the terminal device continuously monitors GNSS position fix validity and reports status to the network device. This feedback mechanism enables timely detection of expiring position fixes and triggers appropriate actions, minimizing the time loss from outdated positioning information

Inventive Principle:
Principle #23Feedback

3Ease of operation

If IoT terminal devices support simultaneous GNSS receiving and LTE transmitting and receiving, then sharing GNSS validity duration becomes easier, but device complexity and resource requirements increase

Engineering Contradiction:
Improvesharing GNSS validity durationVSAvoiddevice capability complexity
Core Design Contradiction:
Ease of operationVSDevice complexity

Solution Approach 1:

The patent extracts the GNSS validity duration information from the complex simultaneous receiving/transmitting operation and treats it as a separate reportable parameter. This extraction allows the information to be reported through standard MAC CE mechanisms without requiring the terminal device to maintain complex simultaneous operation capabilities, thus easing the operational burden while maintaining information sharing

Inventive Principle:
Principle #2Taking out (Extraction)

Data Source

PatentEP4661555A1GNSS validity period transmission method and apparatus, device, and storage medium
Publication Date: 2025.12.10 BEIJING XIAOMI MOBILE SOFTWARE CO LTD
  • EP4661555A1 patent drawingFigure 1~3
  • EP4661555A1 patent drawingFigure 4~7
  • EP4661555A1 patent drawingFigure 8~10

AI summary

The present application relates to the field of communications, and discloses a GNSS validity period transmission method and apparatus, a device, and a storage medium. The method comprises: sending a first media access control (MAC) control element (CE), the first MAC CE carrying a GNSS validity period. An accurate GNSS validity period can be shared between a terminal device and a network device in a timely manner.