Dynamic TTI Allocation for LTE Transmission Delay Reduction
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Solution Overview
Problem
The Long Term Evolution (LTE) communication systems experience significant transmission time delays due to the minimum air interface time delay of 8 ms in round trip time (RTT), which affects user experience and radio network performance, especially in Time Division Duplex (TDD) systems where RTT can reach up to 13 or 16 ms.
Innovation Solution
A wireless communication method where a network device sends control information with first indication information to user equipment to occupy time domain resources for transmission, reducing the transmission time delay to less than 1 ms, allowing for improved user experience and radio network performance by enabling efficient resource allocation and communication.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the minimum air interface time delay of 8 ms in round trip time (RTT) is used in LTE systems, then the system maintains compatibility with existing LTE protocols and frame structures, but the transmission time delay increases significantly, affecting user experience and radio network performance
Solution Approach 1:
The patent segments the traditional 1 ms subframe transmission unit into smaller transmission time intervals (TTIs) of 2 ms or 4 ms. This segmentation allows the system to maintain LTE protocol compatibility at the frame structure level while enabling shorter effective transmission delays through selective use of smaller TTI units for specific data transmissions, thereby resolving the contradiction between protocol compatibility and transmission delay reduction.
Solution Approach 2:
The patent introduces dynamic TTI length adjustment capability, allowing the transmission time interval to be dynamically configured between 2 ms and 4 ms based on service requirements and network conditions. This dynamic adjustment enables the system to adaptively optimize transmission delay while maintaining compatibility with the overall LTE frame structure, resolving the contradiction between fixed protocol constraints and flexible delay optimization.
2Productivity
If TDD configurations are used in LTE systems, then frequency spectrum utilization is improved, but the round trip time (RTT) increases to 13 or 16 ms, significantly worsening transmission time delay
Solution Approach 1:
The patent segments the TDD frame structure into configurable TTI units of 2 ms or 4 ms, allowing selective scheduling of uplink and downlink transmissions within the TDD framework. This segmentation enables the system to maintain TDD spectrum utilization benefits while reducing the effective RTT by allowing faster retransmission and scheduling decisions within the segmented TTI structure, thereby resolving the contradiction between TDD spectrum efficiency and RTT delay.
Data Source
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AI summary
Embodiments of the present invention provide a wirelesswireless communication method, a network device, user equipment, and a system. The method includes: generating, by a network device, control information, where the control information includes first indication information used to indicate a time domain resource for first transmission between user equipment and the network device, and duration of occupying a resource by one transmission of the first transmission is less than 1 millisecond; and sending, by the network device, the control information to the user equipment. The user equipment may obtain, according to the control information, the time domain resource for communicating with the network device by using the first transmission, and communicate with the network device on the obtained time domain resource. Therefore, a transmission time delay can be shortened, and user experience and radio network performance can be greatly improved.