NB-IoT Uplink-Downlink Carrier Frequency Spacing Indication

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Solution Overview

Problem

The existing Narrowband Internet of Things (NB-IoT) technologies face challenges in achieving consistent uplink-downlink carrier frequency spacing, leading to deviations that cause interference and waste of bandwidth due to incorrect frequency allocation, particularly in in-band and guard band operation modes.

Innovation Solution

A method and apparatus that allow the base station to determine and indicate the correct uplink-downlink carrier frequency spacing to terminal devices by generating specific indication information based on the NB-IoT operation mode and application scenarios, ensuring accurate frequency allocation and reducing interference.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If in-band operation mode is used for NB-IoT, then spectrum efficiency is improved by reusing LTE carrier resources, but uplink-downlink carrier frequency spacing deviation occurs causing interference and bandwidth waste

Engineering Contradiction:
Improvespectrum efficiencyVSAvoidfrequency spacing deviation causing interference
Core Design Contradiction:
ProductivityVSObject-generated harmful factors

Solution Approach 1:

The patent changes the frequency spacing parameter from the LTE standard value to an NB-IoT specific value. The base station determines the NB-IoT uplink-downlink carrier frequency spacing based on the actual NB-IoT carrier frequencies, and explicitly indicates this spacing value to terminals through signaling, ensuring terminals use the correct spacing for uplink carrier frequency determination.

Inventive Principle:
Principle #35Parameter changes

2Object-affected harmful factors

If guard band operation mode is used for NB-IoT, then interference to adjacent bands is reduced, but uplink-downlink carrier frequency spacing deviation still occurs leading to bandwidth waste

Engineering Contradiction:
Improveinterference to adjacent bandsVSAvoidfrequency spacing deviation
Core Design Contradiction:
Object-affected harmful factorsVSObject-generated harmful factors

Solution Approach 1:

The patent applies the same parameter change principle for guard band operation. The base station determines the NB-IoT uplink-downlink carrier frequency spacing based on actual NB-IoT carrier frequencies in guard band mode, and indicates this spacing to terminals through signaling, ensuring correct uplink frequency allocation without bandwidth waste.

Inventive Principle:
Principle #35Parameter changes

3Device complexity

If terminals continue to use LTE uplink-downlink carrier frequency spacing definition, then device complexity is reduced, but frequency allocation accuracy deteriorates causing interference and bandwidth waste

Engineering Contradiction:
Improveterminal device complexityVSAvoidfrequency allocation accuracy
Core Design Contradiction:
Device complexityVSMeasurement precision

Solution Approach 1:

The base station provides feedback to terminals about the correct NB-IoT uplink-downlink carrier frequency spacing through indication signaling. This feedback mechanism ensures terminals allocate uplink carrier frequencies accurately according to actual NB-IoT network conditions, resolving the frequency spacing deviation problem while maintaining simple terminal implementation.

Inventive Principle:
Principle #23Feedback

Data Source

PatentEP3361687B1Method of indicating or acquiring interval between uplink and downlink channels, and device utilizing same
Publication Date: 2021.01.06 HUAWEI TECH CO LTD
  • EP3361687B1 patent drawingFigure 1
  • EP3361687B1 patent drawingFigure 2
  • EP3361687B1 patent drawingFigure 3~4

AI summary

The present invention relates to the field of communications technologies, and in particular, to a method and an apparatus for indicating an uplink-downlink carrier frequency spacing, and a method and an apparatus for obtaining an uplink-downlink carrier frequency spacing, so that a terminal obtains a correct NB-IoT system uplink carrier frequency. The method is: obtaining, by a base station, a determining parameter used to determine an uplink-downlink carrier frequency spacing of a first cell, and generating indication information according to the determining parameter, where the indication message is used to indicate the uplink-downlink carrier frequency spacing of the first cell; and sending, by the base station, the indication information to a terminal device UE that initiates a request in the first cell to access an NB-IoT. The method for obtaining an uplink-downlink carrier frequency spacing is: initiating, by UE, a request in a first cell to access an NB-IoT, and receiving an indication message sent by a base station; and determining, by the UE according to the indication information, an uplink-downlink carrier frequency spacing corresponding to the first cell. Therefore, the base station can notify the UE of the uplink-downlink carrier frequency spacing corresponding to the first cell, so that the terminal obtains a correct uplink carrier frequency.