Base Station Channel Quality Measurement Using DM-RS Feedback
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In multi-antenna wireless communication systems, accurately measuring channel quality is challenging due to the complexity of channel state information (CSI) estimation, especially with extended antenna configurations, leading to CQI mismatches that affect data transmission and reception.
Innovation Solution
A method involving a base station with a two-dimensional active antenna system that receives CSI from user equipment, selects precoding and rank based on PMI and RI, and transmits DM-RS and PDSCH to improve CQI feedback accuracy, using either CSI-RS or DM-RS to reduce CQI mismatch.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If multiple antennas are used for MIMO transmission, then data transmission rate and throughput are improved, but channel quality measurement accuracy deteriorates due to increased complexity in CSI estimation
Solution Approach 1:
The patent segments the channel quality measurement process into two distinct phases: initial CSI-based CQI calculation and subsequent DM-RS-based CQI refinement. This segmentation allows the system to use simplified initial measurements while achieving higher accuracy through targeted refinement, thereby maintaining high data transmission rates without sacrificing measurement precision in multi-antenna MIMO systems
Solution Approach 2:
The patent performs preliminary channel quality measurement using CSI before actual data transmission, then uses DM-RS for final CQI refinement. This preliminary action enables the system to prepare transmission parameters in advance while ensuring accurate channel quality assessment, resolving the contradiction between maintaining high transmission rates and achieving precise measurement in complex multi-antenna environments
2Productivity
If extended antenna configuration is used, then system capacity is improved, but CQI mismatch increases affecting transmission reliability
Solution Approach 1:
The patent implements a feedback mechanism where the base station receives CQI feedback from the user equipment and uses it to adjust transmission parameters. By incorporating DM-RS-based CQI refinement, the system continuously improves feedback accuracy even with extended antenna configurations, thereby maintaining both high system capacity and transmission reliability
Solution Approach 2:
The system performs preliminary CQI calculation using CSI and then refines it using DM-RS before final transmission. This preliminary refinement action ensures that CQI mismatch is minimized even when using extended antenna configurations, allowing the system to achieve both high capacity and reliable transmission
Data Source
AI summary
The present invention relates to a method and device for measuring channel quality by a base station having a two-dimensional active antenna system including multiple antennas. Particularly, the method comprises: receiving channel state information (CSI) generated on the basis of a first reference signal relating to a part of multiple antennas, from a terminal; selecting a precoding and a rank based on a precoding matrix indicator (PMI) and a rank indicator (RI) of the received CSI; generating a port by applying the selected precoding and the selected rank; through the generated port, transmitting, to the terminal, a physical downlink shared channel (PDSCH) and a demodulation-reference signal (DM-RS) configured for the terminal; and receiving, from the terminal, a channel quality indication (CQI) feedback for reducing a mismatch for the CQI of the CSI, wherein the CQI feedback may be generated based on the DM-RS.