Grant-Free Uplink Transmission via Reference Signal Differentiation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current wireless communication systems face latency issues in uplink data transmission due to resource allocation based on base station scheduling, which can lead to increased latency and inefficient resource utilization.
Innovation Solution
A method and apparatus for transmitting grant-free uplink data, where a terminal repeatedly transmits transport blocks using pre-scheduled resources and informs the base station of the first transmission point through reference signal changes, allowing for simultaneous transmission of distinct transport blocks on the same resource and enabling selective use of grant-based and grant-free resources.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If base station scheduling is used for resource allocation, then resource utilization is maximized, but uplink data transmission latency increases
Solution Approach 1:
The base station pre-allocates grant-free uplink resources to terminals in advance through semi-static scheduling, allowing terminals to transmit data immediately without waiting for dynamic scheduling grants. This preliminary resource assignment reduces transmission latency while maintaining efficient resource utilization through the pre-configured resource pool.
2Speed
If grant-free uplink resources are used, then transmission speed increases, but resource collision occurs between different terminals
Solution Approach 1:
The grant-free uplink resources are segmented into multiple resource pools, with each pool assigned to specific terminals or terminal groups. This segmentation reduces the probability of collisions by distributing terminals across different resource segments, allowing fast transmission while maintaining reliability through reduced contention.
3Productivity
If a terminal transmits multiple transport blocks, then data throughput increases, but base station signal combining complexity increases
Solution Approach 1:
Reference signals serve as intermediaries that carry identification information for each transport block. The terminal transmits reference signals with embedded identifiers (such as different cyclic shifts or orthogonal codes) that enable the base station to distinguish and separately combine multiple transport blocks without complex processing, thus maintaining high throughput while managing combining complexity.
4Reliability
If reference signal sequences are changed to identify different transport blocks, then transmission reliability improves, but signal processing complexity increases
Solution Approach 1:
The reference signal parameters (such as cyclic shift values, orthogonal cover codes, or frequency offsets) are changed to encode transport block identifiers. This parameter-based differentiation provides reliable identification of multiple transport blocks while keeping the signal structure simple and processing complexity low, as the changes involve only parameter modifications rather than complex signal transformations.
Data Source
AI summary
A method and a device for transmitting an uplink transmission block in a wireless communication system are provided. Particularly, a terminal receives, from a base station, allocation information on a first grant-free uplink resource, which is scheduled semi-persistently. The terminal repeatedly transmits a first transmission block through the first grant-free uplink resource by using a first reference signal. The terminal transmits a second transmission block by using a second reference signal before completion of the transmission of the first transmission block. The second transmission block is distinguished from the first transmission block through a change of the first reference signal to the second reference signal.