HARQ Buffer Flushing for Wireless Data Transmission Reliability

Solution Overview

Problem

In existing HARQ processes, terminals may send outdated information due to interference or noise, leading to incorrect scheduling decisions by network devices, as they incorrectly assume initial transmission has failed and schedule retransmissions, resulting in outdated control information being sent.

Innovation Solution

The proposed method involves a terminal skipping the use of an initial uplink grant for transmission and ignoring subsequent retransmission grants, or considering them as initial transmission grants, thereby reducing outdated information sent to the network device, and flushing the HARQ buffer when necessary to prevent retransmission scheduling errors.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the terminal retransmits the data packet sent for the first time after receiving a retransmission grant, then the terminal maintains data in the HARQ buffer for potential retransmission, but the terminal sends outdated control information to the network device, affecting scheduling decisions

Engineering Contradiction:

Improvedata transmission reliabilityVSAvoidoutdated control information

Core Design Contradiction:

ReliabilityVSLoss of information

Solution Approach 1:

The terminal performs preliminary action by flushing the HARQ buffer when detecting that the scheduled data is different from the stored data. This preliminary flushing prevents the subsequent transmission of outdated control information, ensuring that the network device receives current buffer status reports for accurate scheduling decisions

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The terminal uses feedback mechanism by comparing the currently scheduled data with the stored data in the HARQ buffer. When a difference is detected, the terminal flushes the buffer and updates its state. This feedback loop ensures that the terminal only transmits up-to-date control information, preventing the network device from making incorrect scheduling decisions based on outdated information

Inventive Principle:

Principle #23Feedback

2Productivity

If the terminal stores data in the HARQ buffer for potential retransmission, then the terminal can quickly retransmit data, but the terminal may send outdated buffer status information to the network device

Engineering Contradiction:

Improveretransmission speedVSAvoidbuffer status accuracy

Core Design Contradiction:

ProductivityVSMeasurement precision

Solution Approach 1:

The terminal performs preliminary action by flushing the HARQ buffer when detecting that the scheduled data is different from the stored data. This preliminary flushing prevents the subsequent transmission of outdated control information, ensuring that the network device receives current buffer status reports for accurate scheduling decisions

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The terminal uses feedback mechanism by comparing the currently scheduled data with the stored data in the HARQ buffer. When a difference is detected, the terminal flushes the buffer and updates its state. This feedback loop ensures that the terminal only transmits up-to-date control information, preventing the network device from making incorrect scheduling decisions based on outdated information

Inventive Principle:

Principle #23Feedback

3Productivity

If the network device schedules retransmission based on incorrect decoding assumption, then the network device optimizes resource allocation, but the terminal transmits outdated information reducing scheduling properness

Engineering Contradiction:

Improvescheduling efficiencyVSAvoidscheduling decision accuracy

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The terminal performs preliminary action by flushing the HARQ buffer when detecting that the scheduled data is different from the stored data. This preliminary flushing prevents the subsequent transmission of outdated control information, ensuring that the network device receives current buffer status reports for accurate scheduling decisions

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The terminal uses feedback mechanism by comparing the currently scheduled data with the stored data in the HARQ buffer. When a difference is detected, the terminal flushes the buffer and updates its state. This feedback loop ensures that the terminal only transmits up-to-date control information, preventing the network device from making incorrect scheduling decisions based on outdated information

Inventive Principle:

Principle #23Feedback

Data Source

PatentEP3764575B1Method, device, and storage medium for transmitting data

Publication Date: 2024.10.16 HUAWEI TECH CO LTD

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AI summary

This application provides a data transmission method and apparatus, and a system, to reduce outdated information sent by a terminal to a network device, thereby reducing improper scheduling decisions made by the network device. The method includes: sending a first data packet to a network device, and storing the first data packet; receiving a first uplink grant from the network device, and skipping using the first uplink grant to perform uplink transmission; receiving a second uplink grant from the network device, where the second uplink grant is a grant for retransmission and generated due to a failure of transmission on the first uplink grant; and ignoring the second uplink grant, or transmitting a second data packet to the network device based on the second uplink grant.