eMTC Cell Acquisition Using NB-IoT Synchronization Signals

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Enhanced Machine-Type Communications (eMTC) deployments experience longer cell acquisition times compared to Narrow Band Internet of Things (NB-IoT) deployments, especially in low Signal-to-Noise Ratio (SNR) environments, affecting device performance and battery life.

Innovation Solution

A method where a user equipment (UE) configured for eMTC cell acquisition utilizes NB-IoT synchronization signals to perform at least a portion of the cell acquisition procedure, allowing it to obtain system information and complete the acquisition process more efficiently.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If eMTC deployment is used, then resource flexibility and channel quality feedback are improved, but cell acquisition time increases

Engineering Contradiction:
Improveresource flexibilityVSAvoidcell acquisition time
Core Design Contradiction:
Adaptability or versatilityVSLoss of time

Solution Approach 1:

The cell acquisition procedure is segmented into two parts: first using NB-IoT synchronization signals for initial time and frequency synchronization, then using eMTC acquisition signals for complete cell acquisition. This segmentation allows leveraging the fast synchronization capability of NB-IoT while maintaining eMTC's resource flexibility.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

NB-IoT synchronization signals are used to perform preliminary time and frequency synchronization before the complete eMTC cell acquisition procedure. This preliminary action reduces the overall acquisition time by pre-establishing synchronization.

Inventive Principle:
Principle #10Preliminary action

2Speed

If NB-IoT deployment is used, then maximum coupling loss support and synchronization speed are improved, but resource flexibility is reduced

Engineering Contradiction:
Improvesynchronization speedVSAvoidresource flexibility
Core Design Contradiction:
SpeedVSAdaptability or versatility

Solution Approach 1:

The solution segments the acquisition procedure to use NB-IoT only for the synchronization portion where its speed advantage is needed, while relying on eMTC for the remaining acquisition steps where resource flexibility is beneficial.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

NB-IoT synchronization signals serve as an intermediary to facilitate faster initial synchronization, enabling the device to quickly align with the network before proceeding with eMTC-specific acquisition procedures.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Reliability

If eMTC cell acquisition is performed using eMTC acquisition signals, then protocol consistency is maintained, but acquisition time in low SNR environments increases

Engineering Contradiction:
Improveprotocol consistencyVSAvoidacquisition time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The acquisition procedure is segmented to use NB-IoT synchronization signals only for the initial time and frequency synchronization phase, while maintaining eMTC acquisition signals for subsequent steps to preserve protocol consistency.

Inventive Principle:
Principle #1Segmentation

4Loss of time

If NB-IoT synchronization signals are used for eMTC cell acquisition, then cell acquisition time is reduced, but device complexity increases

Engineering Contradiction:
Improvecell acquisition timeVSAvoiddevice complexity
Core Design Contradiction:
Loss of timeVSDevice complexity

Solution Approach 1:

The device complexity is managed by segmenting the signal processing: using NB-IoT synchronization signals only for initial synchronization reduces the overall processing burden compared to using eMTC signals for the entire acquisition procedure.

Inventive Principle:
Principle #1Segmentation

Data Source

PatentEP3449675B1Enhanced machine-type communications (EMTC) cell acquisition using narrow band (NB-IOT) synchronization channel
Publication Date: 2020.03.04 QUALCOMM INC
  • EP3449675B1 patent drawingFigure 1
  • EP3449675B1 patent drawingFigure 2
  • EP3449675B1 patent drawingFigure 3A

AI summary

Method and apparatus for wireless communication are described for utilizing narrow band (NB-loT) synchronization channel(s) for enhanced machine-type communications (eMTC) cell acquisition. The method and apparatus may perform a first portion of cell acquisition using an NB-loT acquisition signal. A second portion of cell acquisition may be performed using an eMTC acquisition signal determined based at least in part on the NB-loT acquisition signal.