Neighbor Cell CQI Triggering for Lower CSI Reporting Overhead
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Frequent CSI reporting for multiple beams on multiple neighbor cells leads to significant uplink signaling overhead and burdensome processing for wireless transmit/receive units (WTRUs).
Innovation Solution
A wireless transmit/receive unit (WTRU) receives configuration information for measurements and reporting conditions, autonomously detects best SSB resources, and performs dynamic configuration of QCL sources and CSI SSB resources based on these conditions, requesting activation of measurements through MAC CE or DCI when certain criteria are met.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If frequent CSI reporting is performed for multiple beams on multiple neighbor cells, then measurement precision and reliability of cell switching are improved, but uplink signaling overhead and processing burden increase significantly
Solution Approach 1:
The patent extracts and separates the measurement and reporting functions into two distinct types: Type 1 measurements (SSB-based) are performed continuously for cell identification and basic quality assessment, while Type 2 measurements (CSI-RS-based) are extracted and performed only when needed for detailed beam quality reporting. This separation allows the system to maintain measurement precision while reducing unnecessary uplink signaling overhead by not performing full CSI reporting for all neighbor cells continuously.
Solution Approach 2:
The patent implements preliminary action by having the WTRU perform Type 1 SSB measurements in advance to identify candidate neighbor cells and evaluate their basic quality. Based on these preliminary measurements and configured conditions, the WTRU then determines whether to activate Type 2 CSI-RS measurements and reporting. This preliminary assessment prevents unnecessary full CSI reporting for cells that do not meet the triggering conditions, thereby reducing uplink signaling overhead while maintaining measurement precision for relevant cells.
2Reliability
If frequent CSI reporting is performed for multiple beams on multiple neighbor cells, then reliability of fast cell switching is improved, but processing burden on WTRU increases significantly
Solution Approach 1:
The patent divides the measurement and reporting tasks into two extracted components: Type 1 (SSB measurements) which are lighter in processing requirements and performed continuously, and Type 2 (CSI-RS measurements and reporting) which are more processing-intensive but only activated when needed. This extraction reduces the overall processing burden on the WTRU by avoiding continuous execution of the more complex Type 2 measurements for all neighbor cells, while maintaining reliability through conditional activation when switching decisions are critical.
Solution Approach 2:
The patent applies preliminary action by having the WTRU perform Type 1 SSB measurements first to assess neighbor cell quality. Based on these preliminary results and configured conditions, the WTRU determines whether Type 2 CSI-RS measurements are necessary. This preliminary filtering reduces processing burden by avoiding unnecessary execution of complex Type 2 measurements and reporting, while ensuring reliability is maintained by activating Type 2 measurements when cell switching reliability is critical.
3Measurement precision
If Type 2 measurements are activated for all neighbor cells, then measurement precision is improved, but uplink signaling overhead increases
Solution Approach 1:
The patent applies local quality by configuring different measurement and reporting requirements for different neighbor cells based on their individual characteristics and the WTRU's local conditions. Type 2 CSI-RS measurements and reporting are activated locally for specific neighbor cells that meet configured conditions (such as SSB quality thresholds or event-triggered conditions), rather than uniformly for all neighbor cells. This localized approach maintains measurement precision for relevant cells while reducing overall uplink signaling overhead by avoiding reporting for cells where high-precision measurement is not necessary.
Data Source
AI summary
A WTRU may receive configuration information associated with neighbor cells, including indications of a first type of measurement, a second type of measurement, and/or a reporting condition associated with the first type of measurement. The first and second types of measurement may be LI measurements. The WTRU may perform a measurement associated with the first type of measurement on a neighbor cell. The WTRU may determine that the reporting condition is satisfied for the neighbor cell based on the measurement. The WTRU may transmit a request to activate the second type of measurement for the neighbor cell. The WTRU may receive an activation command for reporting a measurement associated with the second type on the neighbor cell. The WTRU may perform the measurement associated with the second type on the neighbor cell, and may transmit a report indicating one or more measurement values associated with the second type of measurement.