CSI Interference Measurement in Unlicensed Band TxOP
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Wireless access systems supporting unlicensed bands face challenges in efficiently transmitting and receiving data due to interference issues, particularly the 'hidden node problem' which affects channel state information measurement and interference averaging.
Innovation Solution
A method for reporting channel state information (CSI) on a transmission opportunity (TxOP) duration in a wireless access system using carrier aggregation, where CSI interference measurement (CSI-IM) is configured and measured within the TxOP duration, allowing for interference averaging and efficient data transmission by setting specific periods and sizes for CSI-IM configuration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If CSI-IM is configured and measured within TxOP duration in unlicensed band, then interference measurement precision is improved, but device complexity increases due to additional configuration and measurement procedures
Solution Approach 1:
The patent segments the interference measurement process by configuring CSI-IM resources specifically within TxOP duration in unlicensed bands, separating it from licensed band operations. This allows precise interference measurement for unlicensed bands without affecting overall system complexity, as the measurement is confined to specific time-frequency resources.
Solution Approach 2:
The patent implements preliminary configuration of CSI-IM resources before TxOP duration begins. The eNodeB configures CSI-IM parameters, resource locations, and measurement timing in advance, allowing the UE to prepare measurement procedures beforehand. This reduces runtime complexity while maintaining measurement precision.
2Measurement precision
If interference averaging is performed over TxOP duration, then channel state information accuracy is improved, but loss of time increases due to extended measurement period
Solution Approach 1:
The patent implements periodic interference measurement within TxOP duration by configuring CSI-IM resources at specific periodic intervals. This allows the UE to perform interference averaging over multiple periodic measurements, improving CSI accuracy while limiting the total time required to the TxOP duration, thus balancing measurement precision with time efficiency.
3Productivity
If carrier aggregation with unlicensed band is implemented, then data transmission efficiency is improved, but reliability decreases due to hidden node problem and interference issues
Solution Approach 1:
The patent implements feedback mechanisms where the UE measures interference using CSI-IM resources within TxOP duration and reports channel state information back to the eNodeB. The eNodeB uses this feedback to adjust transmission parameters, manage carrier aggregation, and mitigate interference from hidden nodes, thereby maintaining reliability while achieving high data transmission efficiency.
Solution Approach 2:
The patent replaces physical layer interference mitigation techniques with higher-layer signaling and processing. Instead of relying solely on physical layer mechanisms, the system uses MAC layer scheduling, RRC configuration of CSI-IM resources, and higher-layer interference coordination to address hidden node problems, enabling carrier aggregation in unlicensed bands with improved reliability.
Data Source
AI summary
A method for transmitting channel state information (CSI) on a transmission opportunity (TxOP) duration by a user equipment (UE) in a wireless communication system supporting a unlicensed band, includes measuring CSI of the TxOP duration based on CSI interference measurement (CSI-IM) and/or CSI reference signal (CSI-RS) in one or more time intervals via the unlicensed band, wherein the one or more time intervals are determined based on a starting point of the TxOP duration; and transmitting the CSI to a base station.