Random Access Timing Gaps for Numerology-Aware Uplink Preparation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing wireless communication systems face challenges in determining optimal time gaps between downlink and uplink transmissions due to varying UE capabilities and numerologies, leading to inefficiencies and potential misalignment in processing and transmission times.

Innovation Solution

The proposed solution involves determining a minimum time gap between downlink and uplink transmissions based on downlink decoding time, uplink transmission preparation time, and higher layer processing latency, which are dependent on numerology, allowing UEs to process downlink messages and generate uplink responses effectively.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a fixed time gap is used between downlink and uplink transmissions, then system simplicity is maintained, but processing reliability deteriorates due to varying UE capabilities and numerologies

Engineering Contradiction:
Improvetime gap determination complexityVSAvoidprocessing reliability
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The patent applies dynamics by making the time gap flexible rather than fixed. The time gap is dynamically determined based on numerology parameters (subcarrier spacing, symbol duration) and UE processing capabilities. This allows the system to adapt the time gap duration to match different numerologies and UE capabilities, ensuring reliable processing while maintaining reasonable system complexity through standardized determination methods.

Inventive Principle:
Principle #15Dynamics

2Reliability

If the time gap is increased to accommodate all UE capabilities, then processing reliability is improved, but communication efficiency deteriorates due to longer waiting times

Engineering Contradiction:
Improveprocessing reliabilityVSAvoidcommunication efficiency
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The patent applies parameter changes by adjusting the time gap duration based on specific parameters including numerology (subcarrier spacing, symbol duration) and UE processing capabilities. Instead of using a conservative fixed time gap that would work for all cases, the system calculates the appropriate time gap by changing parameters according to the actual numerology and UE capability, thereby optimizing the balance between reliability and efficiency for each specific scenario.

Inventive Principle:
Principle #35Parameter changes

3Adaptability or versatility

If multiple numerologies are supported with varying symbol and slot durations, then system versatility is improved, but time gap determination complexity worsens

Engineering Contradiction:
Improvenumerology adaptabilityVSAvoidtime gap determination complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent handles multiple numerologies by systematically changing parameters (subcarrier spacing, symbol duration, slot duration) based on the selected numerology. The time gap is determined by calculating the appropriate number of symbols or slots based on the numerology parameters, providing a standardized method that works across different numerologies without requiring separate complex determination logic for each case.

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP4123951B1Random access timeline and timing adjustment techniques
Publication Date: 2025.11.05 QUALCOMM INC
  • EP4123951B1 patent drawingFigure 1
  • EP4123951B1 patent drawingFigure 2
  • EP4123951B1 patent drawingFigure 3

AI summary

Methods, systems, and devices for wireless communications for determining a minimum time gap between an received downlink message and transmission of an uplink message in response to the received downlink message. In some cases, a user equipment (UE) may receive a downlink message to perform a random access procedure. The UE may determine a minimum time gap based on an uplink transmission preparation time. The UE may transmit a random access preamble based on the minimum time gap. In some examples, the UE may receive a timing advance (TA) command and may determine a minimum time gap between receipt of the TA command and transmission of a time-adjusted uplink message.