Uplink Resource Allocation in TD-LTE Special Sub-frames
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In TD-LTE systems, the limited number of UL sub-frames compared to DL sub-frames results in restricted UL transmission data rate and spectrum efficiency due to the fixed and varying time intervals for UL grant scheduling, ACK/NACK feedback, and retransmission, especially in TDD configurations.
Innovation Solution
The method involves determining UL resources based on DL sub-frame delays, specifically utilizing the UpPTS of special sub-frames to increase UL resource availability, and adjusting the HARQ time sequence table to optimize UL channel transmission, allowing for flexible UL resource allocation and scheduling across different TDD configurations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If time division multiplexing is adopted for UL and DL transmission with fixed time intervals for UL grant scheduling, ACK/NACK feedback, and retransmission, then system simplicity is maintained, but UL transmission resources are limited and UL transmission data rate is reduced
Solution Approach 1:
The patent introduces dynamic UL resource allocation by allowing flexible selection of UL sub-frames and special sub-frames (UpPTS) for UL transmission. The UE determines UL resources based on DL sub-frame delays and configurable parameters, enabling the system to adapt UL transmission timing to available resources rather than being constrained by fixed time intervals. This dynamic approach resolves the contradiction by maintaining system manageability while significantly increasing UL transmission opportunities and data rate.
Solution Approach 2:
The patent utilizes the time dimension by introducing special sub-frames (UpPTS) as additional UL transmission opportunities between traditional UL sub-frames. By configuring multiple possible UL resources (different sub-frames with different delays) and allowing selection based on channel conditions and resource availability, the system effectively adds temporal dimensions to UL resource allocation, thereby increasing UL transmission data rate without proportionally increasing system complexity.
2Quantity of substance
If the number of UL sub-frames is smaller than DL sub-frames in TDD configuration, then DL capacity is ensured, but UL transmission spectrum efficiency is seriously limited
Solution Approach 1:
The patent makes special sub-frames (UpPTS) serve dual purposes: traditionally used for random access and scheduling requests, and now also configured as UL data transmission resources. By allowing UL-SCH transmission in UpPTS when configured by the network, the system maximizes the utilization of available time resources for UL data transmission, thereby improving UL spectrum efficiency without reducing the number of DL sub-frames and maintaining DL capacity.
Solution Approach 2:
The patent introduces configurable parameters (k1, k2, k3) that define the timing relationships between DL sub-frames and corresponding UL resources. By dynamically adjusting these parameters based on TDD configuration and resource availability, the system optimizes UL resource allocation to improve UL transmission spectrum efficiency while preserving the required DL sub-frame quantity for maintaining DL capacity.
3Ease of operation
If fixed time intervals are used for UL grant scheduling, ACK/NACK feedback, and retransmission, then HARQ process management is simplified, but flexibility in UL resource allocation is reduced
Solution Approach 1:
The patent segments the UL resource allocation into multiple configurable time intervals (k1, k2, k3) that can be independently adjusted. Instead of a single fixed time interval, the system divides the timing relationship into separate segments that can be optimized for different HARQ processes and transmission conditions. This segmentation maintains manageable complexity by providing structured configuration options while achieving the desired flexibility in UL resource allocation.
Data Source
Figure 1
Figure 2a
Figure 2b
AI summary
Disclosed in the present application are a message transmission method, user device, base station, and computer storage medium, the method comprising: receiving uplink authorisation information or re-transmission indication information sent by a base station side; on the basis of the serial number of the downlink sub-frame carrying the uplink authorisation information or re-transmission indication information, determining a corresponding at least one sub-frame time delay, and on the basis of the at least one sub-frame time delay, determining at least one uplink resource; the uplink resource being an uplink sub-frame and/or an uplink pilot time slot in a special sub-frame; and implementing uplink shared channel transmission in the at least one uplink resource.