CSI Configuration for SINR Adaptation in LTE
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In LTE systems, the current PDSCH self-adaptation procedure limits UE selection of modulation and coding schemes due to saturated SINR values exceeding the main interval, leading to suboptimal system performance, especially in hotspot scenarios where SINR values are high, and existing methods like 256QAM expansion increase feedback overhead without adequately supporting varying SINR ranges.
Innovation Solution
The method involves determining and notifying UE of multiple resource groups with specific CSI configuration information to indicate CSI candidate sets, allowing precise CSI measurement and data reception using tailored CQI and MCS tables that support different SINR ranges, enabling efficient data transmission across varying interference conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the CQI table is expanded to support higher SINR values (e.g., using 5-bit CQI table instead of 4-bit), then the system can support higher modulation orders and improve performance in high SINR scenarios, but the feedback overhead increases
Solution Approach 1:
The patent dynamically selects between different CQI tables (first CQI table for lower SINR, second CQI table for higher SINR) based on the measured SINR value. This dynamic adaptation allows the system to use the appropriate table size for current channel conditions, improving performance when needed while minimizing feedback overhead during normal operation.
Solution Approach 2:
The patent changes the parameter of CQI table configuration based on SINR conditions. When SINR exceeds a threshold, the system switches from a 4-bit CQI table to a 5-bit CQI table, allowing representation of higher SINR values and support for 256QAM modulation, thereby improving system performance in high-quality channel conditions.
2Loss of information
If the CQI table range is narrowed by deleting low SINR entries to maintain table size, then feedback overhead is reduced, but the system cannot support varying SINR ranges in different subframes
Solution Approach 1:
The patent segments the SINR measurement range into two distinct ranges, each associated with a different CQI table. The first CQI table covers lower SINR values (up to 20 dB), while the second CQI table covers higher SINR values (above 20 dB). This segmentation allows each table to be optimized for its specific range, maintaining compact table sizes while collectively supporting a wide overall SINR range.
Solution Approach 2:
The patent creates a universal CQI reporting mechanism that can handle multiple SINR scenarios through table selection. By maintaining multiple CQI tables with different ranges and selecting the appropriate one based on current SINR conditions, the system achieves multi-functionality, supporting both low-SINR and high-SINR scenarios without requiring a single large table that would increase overhead.
3Device complexity
If saturated processing is used for SINR values exceeding the main interval, then the quantization process remains simple, but the UE is limited to selecting only CQI index 15 and cannot choose higher modulation schemes
Solution Approach 1:
The patent introduces dynamic adaptability to the quantization process by selecting between different CQI tables based on SINR measurements. Instead of always using saturated processing that limits selection to CQI index 15, the system dynamically switches to a second CQI table when SINR exceeds the main interval, enabling the UE to select from multiple high-CQI indices corresponding to higher modulation schemes like 256QAM.
Solution Approach 2:
The patent prepares multiple CQI tables in advance with different SINR ranges and modulation scheme mappings. The second CQI table is pre-configured to support higher SINR values and corresponding higher modulation orders. When high SINR is detected, the system immediately switches to this pre-prepared table, avoiding the need for complex real-time calculations while enabling higher modulation scheme selection.
Data Source
Figure 1~2
Figure 3~4
Figure 5
AI summary
The present invention discloses information notification, information reporting, and data receiving methods and devices, so that a UE performs more precise CQI measurement on a specific measurement resource, or a UE receives data more efficiently on a specific transmission resource. The information notification method includes: determining at least two resource groups and channel state information CSI configuration information corresponding to each of the resource groups, where the at least two resource groups and the CSI configuration information need to be notified to a user equipment UE, and the CSI configuration information is used to indicate a CSI candidate set; and notifying the UE of the at least two resource groups and the CSI configuration information corresponding to each of the resource groups.