Sidelink Subframe Scheduling Offset Mechanism for TDD V2X
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In Time Division Duplex (TDD) V2X communication, there is a challenge in scheduling all sidelink subframes using sidelink grants, particularly when the number of Downlink (DL) subframes is less than the number of Uplink (UL) subframes, leading to unclear timing between sidelink grants and transmissions.
Innovation Solution
The introduction of offset information associated with the location of sidelink subframes allows for scheduling all sidelink subframes using sidelink grants, even when the number of DL subframes is smaller than UL subframes, by defining a new offset mechanism.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If traditional scheduling methods are used in TDD V2X communication, then scheduling can be performed when DL and UL subframes are balanced, but scheduling fails when the number of DL subframes is less than UL subframes
Solution Approach 1:
The patent introduces offset information as a new parameter to modify the scheduling mechanism. This offset value is included in the sidelink grant to indicate the time difference between the grant and the corresponding sidelink transmission, enabling flexible scheduling across all subframe types regardless of the DL-UL imbalance.
Solution Approach 2:
The scheduling process is segmented into distinct components: the sidelink grant transmission, the offset information extraction, and the sidelink transmission execution. This segmentation allows the system to handle the timing relationship explicitly through the offset parameter, resolving the contradiction between scheduling coverage and timing clarity.
2Adaptability or versatility
If offset information is introduced to schedule all sidelink subframes, then scheduling coverage is improved, but signaling overhead increases
Solution Approach 1:
The offset information field in the sidelink grant serves multiple functions: it enables scheduling of all sidelink subframes, provides timing clarification, and maintains backward compatibility with existing systems. This multi-functionality justifies the additional signaling overhead by delivering comprehensive scheduling capability.
3Productivity
If timing between sidelink grant and transmission is not clearly defined, then system complexity is reduced, but scheduling efficiency deteriorates
Solution Approach 1:
The offset information is provided in advance within the sidelink grant, allowing the receiving device to pre-determine the exact timing of the sidelink transmission. This preliminary timing information eliminates ambiguity and enables efficient scheduling without requiring complex real-time timing calculations.
Data Source
Figure 1(a)~1(b)
Figure 2
Figure 3
AI summary
A method for performing a sidelink transmission in a wireless communication system and a device are disclosed in the present specification. In detail, in the present specification, a method for performing a sidelink transmission in a wireless communication system, the method performed by a user equipment (UE) includes receiving, from a base station, a sidelink grant to be used for scheduling of the sidelink transmission, wherein the sidelink grant includes control information indicating an offset of a specific subframe associated with the sidelink grant; determining the specific subframe in consideration of a value indicated by the control information; and performing the sidelink transmission in the specific subframe.