3D Beamforming Channel State Information Feedback Method
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional channel estimation methods in LTE systems only support feedback of channel state information in a horizontal dimension, which is insufficient for 3D beamforming technology that requires channel state information in both horizontal and vertical dimensions.
Innovation Solution
A method for user equipment to select and feed back channel state information-reference signal (CSI-RS) resources from multiple configured ports, allowing the base station to determine channel state information in both horizontal and vertical dimensions, enabling effective 3D beamforming.
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 compatible with existing systems, but only horizontal dimension information is provided which is insufficient for 3D beamforming
Solution Approach 1:
The patent extends conventional 2D channel estimation to 3D channel estimation by adding the vertical dimension. Multiple CSI-RS resources with different spatial filters are configured to enable channel state information acquisition in both horizontal and vertical dimensions, allowing 3D beamforming while maintaining backward compatibility with existing LTE systems through incremental deployment
2Productivity
If 3D beamforming is implemented, then user throughput and average throughput rates are improved, but channel state information feedback complexity increases
Solution Approach 1:
The patent segments the 3D channel state information feedback into multiple components: RI (rank indication), PMI (precoding matrix indicator) for horizontal dimension, and additional PMI/CQI for vertical dimension. This segmentation allows the system to progressively enable 3D beamforming capabilities while managing feedback complexity through configurable reporting modes and selective activation of vertical dimension feedback
3Measurement precision
If channel state information in both horizontal and vertical dimensions is fed back, then precise 3D beamforming is enabled, but feedback overhead and processing complexity increase
Solution Approach 1:
The patent implements partial feedback by allowing the network to configure which dimensions (horizontal only, vertical only, or both) are reported based on deployment scenarios. The feedback overhead is optimized by reporting only the necessary vertical dimension information (additional PMI and CQI) when 3D beamforming is activated, rather than always transmitting complete 3D channel state information
Solution Approach 2:
The patent changes the feedback parameters dynamically based on channel conditions and network configuration. The RI, PMI, and CQI parameters are adjusted according to the rank and quality of channels in different dimensions, allowing the system to adapt feedback quantity and precision to actual network conditions, thereby optimizing the balance between measurement precision and feedback overhead
Data Source
Figure 1A~1B
Figure 1C~2
Figure 3~4
AI summary
Embodiments of the present invention provide a channel state information feedback method, user equipment, and a base station. The method includes: determining, by user equipment, N CSI-RS resources according to a quantity N, configured by a base station, of CSI-RS resources that need to be fed back; performing channel estimation on a port included in the N CSI-RS resources, to obtain channel state information in a horizontal dimension; then selecting M CSI-RS resources from the N CSI-RS resources; and feeding back channel state information of the M CSI-RS resources in the horizontal dimension and indication information of the M CSI-RS resources to the base station, so that the base station determines channel state information in a vertical dimension according to the indication information, so as to finally obtain channel state information in the two dimensions, thereby resolving a problem that channel state information in only a horizontal dimension is fed back during conventional channel estimation.