Uplink Transmission LBT Procedures for URLLC Reliability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current uplink transmission methods in 5G systems face challenges in achieving ultra-reliability and low-latency communication, particularly for eMBB and URLLC traffic, due to limitations in modulation and coding schemes, which affect error rates and latency, and require efficient resource allocation and channel access schemes.
Innovation Solution
The proposed solution involves a terminal performing listen-before-talk (LBT) procedures for uplink transmissions, with specific schemes and channel access methods indicated by downlink control information (DCI), allowing for consecutive transmissions with varying time intervals and channel access types based on channel occupancy times, enabling efficient resource utilization and reliability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If repetitive transmission is used to achieve lower error rate, then reliability is improved, but latency increases
Solution Approach 1:
The patent segments the uplink transmission into multiple independent transmission opportunities with different LBT procedures. The first uplink transmission uses a first LBT procedure while the second uplink transmission uses a second LBT procedure, allowing each transmission to be optimized independently for reliability without requiring repetitive transmission of the same data, thus reducing latency.
Solution Approach 2:
The patent dynamically selects between different LBT procedures (first LBT and second LBT) based on channel conditions and transmission requirements. This dynamic approach allows the system to adaptively balance between reliability and latency by choosing the appropriate LBT procedure for each transmission opportunity rather than using a fixed repetitive transmission scheme.
2Reliability
If lower MCS is applied to reduce error rate, then reliability is improved, but transmission power efficiency deteriorates
Solution Approach 1:
The patent changes the LBT procedure parameters and timing intervals between transmissions rather than relying solely on MCS changes. By adjusting the time interval between first and second uplink transmissions and selecting different LBT procedures, the system achieves reliable communication without necessarily using lower MCS, thereby maintaining transmission power efficiency.
3Productivity
If multiple LBT procedures are performed for consecutive transmissions, then resource allocation efficiency is improved, but device complexity increases
Solution Approach 1:
The patent designs the LBT procedures to serve multiple functions: the first LBT procedure and second LBT procedure not only control channel access but also implicitly manage resource allocation efficiency for different transmission types. This multi-functionality reduces the need for separate complex resource allocation mechanisms, thereby limiting the increase in device complexity while maintaining improved productivity.
Data Source
AI summary
An uplink transmission method performed by a terminal includes: receiving, from a base station, at least one DCI for allocating first uplink transmission and second uplink transmission; performing a first LBT procedure for the first uplink transmission, and performing the first uplink transmission when the first LBT procedure is successful; and performing a second LBT procedure for the second uplink transmission, and performing the second uplink transmission when the second LBT procedure is successful, wherein the first uplink transmission and the second uplink transmission are consecutively performed with a time interval longer than a predetermined time.