Sidelink LBT Failure Counting for Unlicensed Band Coexistence
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional mechanisms lack the ability to enable sidelink transmissions to coexist with other wireless technologies in the unlicensed band, particularly in 5G NR-U, due to insufficient listen-before-talk (LBT) mechanisms for sidelink communications.
Innovation Solution
A method and apparatus for a terminal device to perform a listen-before-talk (LBT) procedure, generate LBT failure indications, and determine consistent LBT failures based on a predetermined threshold, allowing sidelink communications to coexist with other wireless technologies by counting failure indications per resource pool or bandwidth part.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional mechanisms are used for sidelink transmission in unlicensed band, then device complexity is reduced, but reliability deteriorates due to inability to coexist with other wireless technologies
Solution Approach 1:
The patent segments the LBT failure handling mechanism by introducing separate counters for different failure scenarios: counter1 for LBT failures and counter2 for consistent LBT failures. This segmentation allows the system to track and manage different types of channel access failures independently, improving reliability by providing more granular control over coexistence behavior with other wireless technologies like WiFi.
Solution Approach 2:
The patent implements preliminary action by performing LBT procedures before actual sidelink transmission in unlicensed bands. The terminal device proactively checks channel availability, counts LBT failures, and determines consistent LBT failures in advance, allowing it to adjust transmission behavior before attempting communication, thereby ensuring reliable coexistence with other wireless technologies.
2Reliability
If LBT procedure is implemented for sidelink transmission, then coexistence with other wireless technologies is improved, but loss of time increases due to channel sensing requirements
Solution Approach 1:
The patent applies partial action by implementing LBT procedures selectively for sidelink transmissions in unlicensed bands rather than universally. The terminal device performs channel sensing and LBT procedures only when needed for unlicensed band transmission, counting failures with counter1 and counter2 mechanisms, thereby achieving coexistence improvement without excessive time loss in all transmission scenarios.
3Measurement precision
If LBT failure counting mechanism is implemented, then measurement precision is improved for failure detection, but device complexity increases due to additional counting and threshold comparison
Solution Approach 1:
The patent segments the failure detection mechanism into two distinct counters: counter1 for tracking individual LBT failures and counter2 for tracking consistent LBT failures. This segmentation provides precise measurement of different failure types, allowing the system to accurately detect and respond to channel access issues while maintaining manageable complexity through clear separation of counting functions.
Solution Approach 2:
The patent implements feedback mechanisms where the terminal device continuously monitors LBT failure counts using counter1 and counter2, compares these counts against predetermined thresholds, and adjusts transmission behavior based on the feedback. This feedback loop enables precise failure detection and appropriate response actions, improving measurement precision while maintaining systematic complexity management.
Data Source
AI summary
Embodiments of the present disclosure relate to a solution for supporting an LBT mechanism for sidelink transmissions. In a method for communication, a terminal device starts a listen-before-talk (LBT) procedure. The terminal device generates an LBT failure indication if a channel for a side Link transmission is occupied during the LBT procedure. If the number of LBT failure indications is equal to or greater than a predetermined number threshold, the terminal device determines a consistent LBT failure associated with the sidelink transmission. In this way, the sidelink transmission associated with the terminal device can coexist with other transmissions based on other wireless technologies, for example, on an unlicensed band.