LTE TDD Subframe Scheduling for Retransmission Conflict Avoidance

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In the LTE TDD mode, data packet retransmissions can lead to conflicts when dynamical subframes are adjusted, resulting in inefficient resource utilization and reduced data transmission performance and scheduling flexibility due to mismatches between uplink and downlink configurations and instantaneous service requirements.

Innovation Solution

The evolved NodeB (eNB) selects a second subframe from a plurality of subframes and sends scheduling signaling to the User Equipment (UE) to retransmit data packets, avoiding conflicts by identifying suitable subframes based on an uplink scheduling sequence, ensuring no downlink data is transmitted in the selected subframe, thus improving data transmission performance and scheduling flexibility.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If dynamic subframes are introduced to improve resource utilization flexibility, then scheduling flexibility is improved, but data transmission conflicts occur when retransmitting packets

Engineering Contradiction:
Improvescheduling flexibilityVSAvoiddata transmission reliability
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

The patent applies dynamics by making the retransmission subframe selection adaptive to the current TDD configuration. Instead of using a fixed preconfigured subframe, the eNB dynamically determines the retransmission subframe based on the current uplink-downlink configuration, ensuring the selected subframe is always available for uplink transmission regardless of dynamic changes.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent uses feedback mechanisms where the eNB monitors the current TDD configuration and adjusts the retransmission scheduling accordingly. The eNB provides feedback through scheduling signaling to the UE about which subframe to use for retransmission, ensuring both parties are synchronized with the current configuration state.

Inventive Principle:
Principle #23Feedback

2Productivity

If preconfigured uplink subframes are used for retransmission, then retransmission timing is simplified, but resource utilization efficiency decreases when configurations mismatch instantaneous service requirements

Engineering Contradiction:
Improveresource utilization efficiencyVSAvoidscheduling complexity
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The patent changes the parameter of retransmission subframe selection from a fixed preconfigured value to a dynamically determined value based on current TDD configuration. This allows the system to adapt to changing service requirements while maintaining clear scheduling rules through standardized selection criteria.

Inventive Principle:
Principle #35Parameter changes

3Stability of the object's composition

If fixed TDD configurations are used according to average service requirements, then system stability is improved, but resource utilization efficiency decreases due to mismatch with instantaneous service requirements

Engineering Contradiction:
Improveconfiguration stabilityVSAvoidresource utilization efficiency
Core Design Contradiction:
Stability of the object's compositionVSProductivity

Solution Approach 1:

The patent introduces dynamics into the retransmission scheduling process while maintaining stability in the overall TDD configuration framework. The eNB can adjust the retransmission subframe selection based on instantaneous service requirements and current configuration, allowing the system to respond to changing demands without destabilizing the fundamental TDD structure.

Inventive Principle:
Principle #15Dynamics

Data Source

PatentEP2683104B1Data transmission method, evolved nodeb and user equipment
Publication Date: 2019.04.17 HUAWEI TECH CO LTD
  • EP2683104B1 patent drawingFigure 1~2
  • EP2683104B1 patent drawingFigure 3~4
  • EP2683104B1 patent drawingFigure 5~7

AI summary

The embodiments of the present invention disclose a data transmission method, an evolved NodeB (eNB) and a User Equipment (UE), which can avoid data transmission conflict, and improve data transmission performance and scheduling flexibility. The method according to the embodiments of the present invention comprises: selecting, by an eNB, a second subframe from a plurality of subframes, when the eNB does not correctly receive a data packet transmitted by a UE in a first subframe; and transmitting, by the eNB, a scheduling signaling to the UE, so that the UE transmits a retransmission packet of the data packet in the second subframe. The embodiments of the present invention further provide an eNB and a UE. The embodiments of the present invention can effectively avoid data transmission conflict, and improve data transmission performance and scheduling flexibility.