Wireless ACK Feedback Grouping for Unlicensed Spectrum Reliability

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Wireless communications systems face challenges in providing reliable acknowledgment feedback, particularly in unlicensed radio frequency spectrums where transmissions may not be received correctly due to hidden interfering nodes or medium occupancy, leading to inefficiencies and increased latency.

Innovation Solution

Implementing enhanced dynamic or group-based acknowledgment feedback techniques, including hybrid automatic repeat request (HARQ) feedback for multiple downlink transmissions, with configurations for both group-based and one-shot feedback, and utilizing uplink DCI parameters like DAI and NFI to determine feedback reports, allowing efficient and reliable feedback reporting across multiple component carriers.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If traditional acknowledgment feedback is used in unlicensed spectrum, then transmission reliability deteriorates due to hidden interfering nodes and medium occupancy, but switching to enhanced group-based feedback increases system complexity

Engineering Contradiction:
Improveacknowledgment feedback reliabilityVSAvoidfeedback system complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent segments downlink transmissions into multiple groups (first group, second group, etc.) and assigns separate acknowledgment feedback for each group. This allows the system to provide reliable feedback for each transmission group independently, addressing the reliability issue in unlicensed spectrum while managing complexity through structured organization of feedback processes.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent implements dynamic feedback mechanisms where the wireless device can transmit different types of feedback (group-based or one-shot) based on received downlink control messages. The feedback approach adapts dynamically to transmission conditions, with the ability to switch between providing feedback for specific transmission groups or providing comprehensive feedback across all groups, thereby balancing reliability with system complexity.

Inventive Principle:
Principle #15Dynamics

2Loss of information

If one-shot feedback is transmitted for all configured feedback processes, then feedback completeness is improved, but feedback transmission latency increases

Engineering Contradiction:
Improvefeedback information completenessVSAvoidfeedback transmission latency
Core Design Contradiction:
Loss of informationVSLoss of time

Solution Approach 1:

The patent enables dynamic selection between group-based feedback and one-shot feedback mechanisms. When a downlink control message indicates one-shot feedback is needed, the wireless device transmits comprehensive feedback for all configured feedback processes. Otherwise, it transmits feedback for specific transmission groups only. This dynamic approach ensures feedback completeness when necessary while minimizing latency in normal operating conditions.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The system changes the feedback transmission parameter based on received control information. The feedback scope parameter can be adjusted between 'specific group' and 'all groups' modes, allowing the system to optimize between information completeness and transmission latency by selecting the appropriate feedback scope for each transmission scenario.

Inventive Principle:
Principle #35Parameter changes

3Productivity

If group-based feedback is used for multiple downlink transmissions, then feedback efficiency is improved, but handling medium occupancy and LBT failures becomes more complex

Engineering Contradiction:
Improvefeedback reporting efficiencyVSAvoidmedium access control complexity
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

By segmenting feedback into transmission groups, the system can efficiently manage feedback for multiple downlink transmissions. Each group can be handled independently, allowing the wireless device to provide feedback for successfully received groups while dealing with LBT failures or medium occupancy issues on a per-group basis, thereby improving overall feedback efficiency while managing complexity through modular group handling.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent implements feedback mechanisms where downlink control messages indicate whether group-based or one-shot feedback should be transmitted. This feedback loop allows the system to adapt to medium occupancy conditions and LBT failures, with the ability to request comprehensive feedback when transmission reliability is in doubt, thereby improving productivity while providing structured handling of medium access challenges.

Inventive Principle:
Principle #23Feedback

Data Source

PatentEP4055745B1Acknowledgment feedback techniques in wireless communications
Publication Date: 2026.02.25 QUALCOMM INC
  • EP4055745B1 patent drawingFigure 1
  • EP4055745B1 patent drawingFigure 2
  • EP4055745B1 patent drawingFigure 3

AI summary

Methods, systems, and devices for wireless communications are described that enable efficient group-based acknowledgment feedback reporting. Techniques are provided for feedback for a number of different downlink transmissions to be reported by a user equipment (UE) using transport block level feedback, code block group level feedback, or combinations thereof. Acknowledgment feedback may be provided in one or more group-based or enhanced dynamic feedback reports, a one-shot feedback report, or any combinations thereof.