CSI Reporting for Active Antenna Systems
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current communication systems face inefficiencies in measuring and reporting channel state information (CSI) for advanced antenna systems, particularly in active antenna systems with two-dimensional antenna arrays, leading to increased overhead and complexity, especially when backward compatibility with older systems is required.
Innovation Solution
A method involving user equipment that receives a first reference signal set from a base station, determines CSI, and sends it back, allowing the base station to adjust and send a second reference signal set for more precise CSI measurement, utilizing specific precoding matrices and codebooks to optimize channel state reporting.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a two-dimensional antenna array is used in active antenna systems, then system capacity and coverage are improved, but reference signal overhead and system complexity increase
Solution Approach 1:
The patent segments the two-dimensional antenna array into multiple one-dimensional antenna arrays (e.g., horizontal and vertical arrays). Each one-dimensional array has its own codebook and CSI reporting mechanism. This segmentation allows the system to handle 2D arrays using established 1D processing methods, reducing the complexity and overhead associated with directly supporting 2D arrays.
Solution Approach 2:
The patent enables existing one-dimensional codebooks and CSI reporting mechanisms to serve multiple functions by applying them separately to different one-dimensional subsets of the two-dimensional antenna array. This universal approach allows legacy 1D processing infrastructure to handle 2D array scenarios without requiring entirely new 2D-specific protocols.
2Productivity
If a two-dimensional antenna array is used in active antenna systems, then system capacity and coverage are improved, but device complexity increases
Solution Approach 1:
The patent divides the complex two-dimensional antenna array processing into separate one-dimensional processing tasks. Each one-dimensional array is processed independently using its own codebook and CSI reporting mechanism, which simplifies the overall system complexity while maintaining the benefits of the 2D array configuration.
Solution Approach 2:
The patent introduces dynamic selection mechanisms where the network can flexibly configure which one-dimensional arrays are active and how CSI is reported for each. This dynamic approach allows the system to adapt complexity levels based on actual channel conditions and service requirements, rather than always operating at maximum complexity.
3Adaptability or versatility
If existing LTE R8/R10 codebooks are used for conventional base stations, then backward compatibility is maintained, but they are not optimized for active antenna systems with two-dimensional arrays
Solution Approach 1:
The patent applies existing one-dimensional codebooks separately to different one-dimensional subsets of the two-dimensional antenna array. This segmentation allows the use of proven, backward-compatible 1D codebooks while effectively representing the 2D array structure through the combination of multiple 1D codebook applications.
Solution Approach 2:
The patent combines the results from multiple one-dimensional CSI reporting processes to form the overall CSI for the two-dimensional antenna array. By merging the horizontal and vertical array CSI information, the system achieves accurate 2D channel state representation using reliable 1D measurement techniques.
Data Source
Figure 1-1A~1-2A
Figure 1-2B~2
Figure 3A
AI summary
The present invention discloses a method for reporting channel state information, user equipment, and a base station. The method includes: receiving a first reference signal set sent by a base station, where the first reference signal set includes at least two reference signals; sending first CSI to the base station, where the first CSI is determined according to the first reference signal set, and the first CSI includes a first RI and/or a first PMI, where the first PMI is used to indicate a first precoding matrix; receiving a second reference signal set sent by the base station, where the second reference signal set is determined based on the first CSI, and the second reference signal set includes at least one reference signal; and sending second CSI to the base station, where the second CSI is determined according to the second reference signal set. The method for reporting channel state information, the user equipment, and the base station in the embodiments of the present invention can improve system efficiency or performance.