3D Channel State Information Feedback via Vertical Dimension Reference Signals
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Solution Overview
Problem
Conventional channel estimation methods in LTE systems only support channel state information feedback in the horizontal dimension, which is inadequate for 3D beamforming technologies that require feedback in both horizontal and vertical dimensions.
Innovation Solution
Configuring and sending multiple reference signal resources by the base station to user equipment, allowing the equipment to determine and feedback channel state information and reference signal resource indication information in both dimensions, enabling the base station to obtain channel state information in both dimensions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If conventional channel estimation method is used, then channel state information feedback is simple and easy to implement, but only horizontal dimension channel state information can be obtained, which is insufficient for 3D beamforming technology
Solution Approach 1:
The patent extends conventional 2D channel estimation (horizontal dimension only) to 3D channel estimation by adding vertical dimension. Multiple reference signal resources with different spatial filters are configured to capture channel characteristics in both horizontal and vertical dimensions, enabling 3D beamforming technology to obtain comprehensive channel state information.
Solution Approach 2:
The channel estimation process is segmented into multiple independent reference signal resources, each corresponding to different spatial directions or beams. The user equipment measures each reference signal resource separately and combines the measurements to obtain complete 3D channel state information, making the complex estimation process manageable and systematic.
2Measurement precision
If multiple reference signal resources are configured for 3D beamforming, then channel state information in both horizontal and vertical dimensions can be obtained, but feedback overhead and processing complexity increase
Solution Approach 1:
The patent extracts only the essential channel state information parameters (such as channel quality indicator, precoding matrix indicator, and rank indicator) from the complete 3D channel measurements and feeds back only these extracted parameters to the base station. This reduces feedback overhead while maintaining the precision needed for 3D beamforming operations.
Solution Approach 2:
The patent transforms the raw channel measurement data into compressed parameter representations (CQI, PMI, RI) that capture the essential channel characteristics in both horizontal and vertical dimensions. This parameter transformation reduces the amount of data to be fed back while preserving the measurement precision required for accurate 3D beamforming.
Data Source
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AI summary
This application provides a channel state information feedback method, user equipment, and a base station. A base station configures N first reference signal resources for UE, and sends the N first reference signal resources to the UE. After receiving the first reference signal resources, and then determining CSI of the first reference signal resources and M pieces of first reference signal indication information based on a feedback mode, the UE feeds back the CSI and the M pieces of first reference signal resource indication information to the base station. In this process, the UE feeds back the CSI of the M first reference signal resources in a horizontal dimension and the M pieces of first reference signal resource indication information to the base station, so that the base station determines channel state information in a vertical dimension based on the first reference signal resource indication information and finally obtains the channel state information in the two dimensions. This overcomes a disadvantage that only channel state information in a horizontal dimension is fed back in conventional channel estimation.