User Equipment LBT Switching Across Bandwidth Parts in Unlicensed Bands
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In unlicensed bands, communication apparatuses face limited transmission opportunities due to Listen Before Talk (LBT) failures, which are triggered by interfering signals from other systems, leading to inefficient use of the unlicensed spectrum in NR-U communication.
Innovation Solution
Implementing a communication control method that configures multiple bandwidth parts (BWPs) within a carrier frequency, performs LBT checks across these BWPs, and adjusts transmission based on LBT success, along with inter-layer coordination and congestion evaluation to optimize transmission opportunities.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If Listen Before Talk (LBT) is performed in unlicensed bands, then transmission opportunities are secured to avoid interference, but transmission efficiency deteriorates due to LBT failures caused by interfering signals from other systems
Solution Approach 1:
The patent changes the parameter of transmission frequency by introducing multiple bandwidth parts (BWPs) within a carrier frequency. When LBT fails on one BWP, the system switches to another BWP, thereby changing the transmission parameter to overcome the blocking effect and improve both reliability and efficiency
Solution Approach 2:
The patent segments the carrier frequency into multiple bandwidth parts (BWPs). This segmentation allows the system to perform LBT checks on individual BWPs and switch between them, transforming a single-point failure mode into a multi-path transmission approach that maintains efficiency while ensuring reliability
2Adaptability or versatility
If multiple bandwidth parts (BWPs) are configured within a carrier frequency, then transmission flexibility is improved to overcome LBT failures, but device complexity increases due to additional configuration and management requirements
Solution Approach 1:
The patent makes the bandwidth parts serve multiple functions: they are both frequency resources for data transmission and diversity resources for overcoming LBT failures. This multi-functionality increases adaptability while the standardized BWP configuration framework keeps complexity manageable
Data Source
AI summary
A communication control method is used in a user equipment in a cell operated in an unlicensed band. The communication control method comprises performing, by the user equipment, Listen Before Talk (LBT) before preforming transmission in the cell; determining, by the user equipment, whether the number of the LBT failure reaches a threshold; and when determining that the number of the LBT failure reaches the threshold, performing, by the user equipment, transmission in another cell in which the number of the LBT failure does not reach the threshold.