Timing Advance Adjustment for Multiple Subcarrier Spacing

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

The existing timing advance mechanisms in telecommunication systems, particularly in New Radio Access (NR), are not suitable for multiple subcarrier spacing values, leading to inaccuracies in uplink transmission timing adjustments for terminal devices.

Innovation Solution

A method and apparatus that determine a timing advance value based on the Physical Random Access Channel (PRACH) sequence and subcarrier spacing values, allowing for more precise timing adjustments by enabling the network device to transmit an indication to the terminal device for adjusting uplink transmission timing.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a fixed timing advance value based on fixed time unit and fixed subcarrier spacing is used, then the timing advance mechanism is simple to implement, but it is not suitable for multiple subcarrier spacing values in NR

Engineering Contradiction:

Improveadaptability to multiple subcarrier spacing valuesVSAvoidcomplexity of timing advance determination

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent changes the parameters used for timing advance determination from fixed values to values that vary with subcarrier spacing. Specifically, the time unit is changed from a fixed value to one that is determined based on the subcarrier spacing value, allowing the timing advance to be accurately calculated for different subcarrier spacing configurations in NR

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent introduces dynamic adjustment of timing advance parameters based on the subcarrier spacing. The network device determines the timing advance value dynamically by considering the actual subcarrier spacing being used, rather than relying on a static fixed value, enabling the system to adapt to changing transmission conditions

Inventive Principle:

Principle #15Dynamics

2Measurement precision

If timing advance adjustment is not optimized for multiple subcarrier spacing values, then the system is easier to implement, but uplink transmission timing accuracy deteriorates

Engineering Contradiction:

Improveaccuracy of uplink transmission timingVSAvoidcomplexity of timing advance mechanism

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent improves timing accuracy by changing the time unit parameter to be dependent on subcarrier spacing. The time unit is determined as a function of the subcarrier spacing value, ensuring that timing advance calculations are precisely adapted to the actual transmission parameters being used

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The network device provides timing advance commands to the terminal device based on measured uplink reception timing. This feedback mechanism allows the system to continuously adjust and refine the timing advance value to maintain accurate synchronization, with the feedback loop incorporating awareness of the current subcarrier spacing configuration

Inventive Principle:

Principle #23Feedback

3Reliability

If fixed timing advance values are used across different subcarrier spacing values, then the mechanism is simpler to operate, but orthogonality and intra-cell interference reduction are compromised

Engineering Contradiction:

Improveuplink orthogonality and interference reductionVSAvoidease of timing advance adjustment

Core Design Contradiction:

ReliabilityVSEase of operation

Solution Approach 1:

The patent ensures reliable uplink orthogonality by changing the time unit parameter to scale with subcarrier spacing. This parameter adaptation ensures that timing advance values are correctly calculated for each subcarrier spacing configuration, maintaining proper uplink synchronization and orthogonality across different NR scenarios

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The system dynamically adjusts the timing advance based on the active subcarrier spacing value. The network device determines appropriate timing advance values by considering the current subcarrier spacing, and the terminal device applies these dynamic adjustments to maintain reliable uplink transmission timing

Inventive Principle:

Principle #15Dynamics

Data Source

PatentUS11184931B2Methods and apparatuses for timing advance adjustment

Publication Date: 2021.11.23 NEC CORP

AI summary

Embodiments of the present disclosure relate to methods and devices for timing advance adjustment. In example embodiments, a method implemented in a network device is provided. According to the method, in response to receiving a Physical Random Access Channel (PRACH) sequence from a terminal device served by the network device, a first value indicating an adjustment of timing advance is determined based on the PRACH sequence and at least one value of subcarrier spacing. An indication of the first value is transmitted to the terminal device to enable the terminal device to adjust timing of uplink transmission.