Flexible TDD Subframe Structure for Latency Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Wireless communication systems using traditional TDD subframe structures face significant latency issues due to the designation of entire subframes for uplink or downlink operations, which restricts throughput and responsiveness.
Innovation Solution
The implementation of adaptive subframes that dynamically allocate both uplink and downlink regions within a single subframe, allowing for reduced latency by integrating both transmission directions and using flexible TDD subframe structures that can be configured based on user equipment capabilities and configurations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If entire subframes are designated for uplink or downlink operations in traditional TDD structures, then clear transmission direction separation is achieved, but latency increases and throughput is restricted
Solution Approach 1:
The subframe is segmented into multiple regions with different transmission directions. Specifically, the subframe is divided into downlink regions (including downlink control region and downlink data region), uplink regions (including uplink data region and uplink control region), and guard periods. This segmentation allows different parts of the subframe to serve different purposes, enabling simultaneous uplink and downlink operations while maintaining clear direction separation where needed.
Solution Approach 2:
The TDD subframe structure is made dynamic by allowing flexible configuration of region boundaries, durations, and positions based on traffic conditions. The network can adaptively adjust the length of downlink regions, uplink regions, and guard periods, and reconfigure subframe directions in real-time. This dynamic adaptability enables the system to optimize for low latency when needed while maintaining reliable direction separation when required.
2Device complexity
If entire subframes are designated for uplink or downlink operations, then simple subframe configuration is maintained, but responsiveness and throughput are restricted
Solution Approach 1:
The subframe is segmented into multiple regions with different transmission directions. Specifically, the subframe is divided into downlink regions (including downlink control region and downlink data region), uplink regions (including uplink data region and uplink control region), and guard periods. This segmentation allows different parts of the subframe to serve different purposes, enabling simultaneous uplink and downlink operations while maintaining clear direction separation where needed.
Solution Approach 2:
The system employs parameter changes by allowing flexible configuration of subframe structures with varying region durations, positions, and directions. Configuration parameters such as the length of downlink regions, uplink regions, and guard periods can be adjusted based on traffic conditions. The network can dynamically change these parameters to optimize throughput while managing complexity through standardized configuration options.
3Stability of the object's composition
If traditional TDD subframe structures are used, then standardized transmission patterns are maintained, but latency reduction opportunities are lost
Solution Approach 1:
The TDD subframe structure is made dynamic by allowing flexible configuration of region boundaries, durations, and positions based on traffic conditions. The network can adaptively adjust the length of downlink regions, uplink regions, and guard periods, and reconfigure subframe directions in real-time. This dynamic adaptability enables the system to optimize for low latency when needed while maintaining reliable direction separation when required.
Solution Approach 2:
The flexible TDD subframe structure enables continuous useful action by allowing overlapping or back-to-back uplink and downlink transmissions within the same subframe. By eliminating idle periods and maximizing the utilization of available time resources for actual data transmission, the system maintains continuous productive communication activity, thereby reducing overall latency while preserving pattern stability through configurable frameworks.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Methods, systems, and devices for wireless communication are described. A wireless device may identify an uplink/downlink (UL/DL) configuration that defines subframe configuration options for each subframe of a frame. For example, the UL/DL configuration may establish parameters for time division duplexing (TDD) operation between a base station and a user equipment (UE). The wireless device (e.g., the UE or base station) may determine a constraint for a subframe of the frame based on the UL/DL configuration and then determine an adaptive subframe configuration based on the constraint. The adaptive subframe configuration may include one or several downlink symbol periods and one or several uplink symbol periods. The wireless device may then communicate during the subframe according to the adaptive subframe configuration rather than the original UL/DL configuration; and, because the adaptive subframe may be constrained by the identified UL/DL configuration, the communication during the subframe may avoid disruption to UEs.