16-Port CSI-RS Configuration for Overhead Reduction

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current LTE systems face challenges in configuring and performing CSI feedback for 16-port CSI-RS, particularly in terms of high overhead and interference, especially when the number of ports is large, which affects system performance and efficiency.

Innovation Solution

The method involves determining and configuring specific Resource Elements (REs) for 16-port CSI-RS, either by selecting from existing REs or combining 8-port CSI-RS configurations, to minimize interference and optimize resource allocation, allowing for efficient CSI feedback and reduced overhead.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If Full port CSI-RS (all CSI-RS ports) is used for CSI feedback, then comprehensive channel information can be obtained, but CSI-RS overhead becomes excessively high when the number of ports is large

Engineering Contradiction:
Improvechannel information estimation accuracyVSAvoidCSI-RS overhead
Core Design Contradiction:
Measurement precisionVSQuantity of substance

Solution Approach 1:

The patent segments the 32 TXRUs into multiple groups (e.g., 4 groups of 8 TXRUs each) and configures separate CSI-RS resources for each group. This allows the system to obtain comprehensive channel information for all 32 TXRUs while only activating CSI-RS for a subset of groups, thereby reducing overall CSI-RS overhead while maintaining measurement precision for the active groups.

Inventive Principle:
Principle #1Segmentation

2Adaptability or versatility

If the number of CSI-RS ports is increased to support more TXRUs, then more comprehensive channel coverage is achieved, but interference between cells increases

Engineering Contradiction:
Improvechannel coverage capabilityVSAvoidinter-cell interference
Core Design Contradiction:
Adaptability or versatilityVSObject-affected harmful factors

Solution Approach 1:

The patent divides the large-scale antenna array into multiple smaller groups, each with its own CSI-RS configuration. This segmentation allows different cell groups to use different CSI-RS resource configurations, reducing the probability of resource collision and interference between cells while maintaining the ability to support a large total number of TXRUs across all groups.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent introduces group-level indexing in addition to port-level indexing. By organizing CSI-RS resources in a hierarchical structure (groups × ports), the system can differentiate between multiple cells more effectively, reducing inter-cell interference while supporting comprehensive channel coverage across all TXRUs.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

3Loss of information

If 16-port CSI-RS is configured for all cells, then complete channel state information is obtained, but system overhead and processing complexity increase significantly

Engineering Contradiction:
Improvechannel state information completenessVSAvoidconfiguration and processing complexity
Core Design Contradiction:
Loss of informationVSDevice complexity

Solution Approach 1:

The patent segments the channel state information acquisition process into group-level and port-level operations. By first determining which TXRU groups are active and then configuring CSI-RS only for those groups, the system reduces the total number of CSI-RS ports that need to be configured and processed, thereby reducing complexity while maintaining information completeness for the active groups.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent implements partial CSI-RS configuration by activating only the necessary groups and ports based on actual channel conditions and requirements. Instead of configuring all 16 ports for all cells unconditionally, the system dynamically selects which groups and ports require CSI-RS, reducing overall complexity while ensuring sufficient channel state information is obtained for active transmissions.

Inventive Principle:
Principle #16Partial or excessive action

Data Source

PatentEP3442288B1CSI-RS configuration and CSI feedback method and apparatus
Publication Date: 2021.03.24 CHINA MOBILE COMM GRP CO LTD
  • EP3442288B1 patent drawingFigure 1
  • EP3442288B1 patent drawingFigure 2
  • EP3442288B1 patent drawingFigure 3

AI summary

Disclosed are a CSI-RS configuration and CSI feedback method and apparatus, and a relevant device, which are used for implementing 16-port CSI-RS configuration and performing CSI feedback based on a 16-port CSI-RS. The CSI-RS configuration method comprises: determining 16-port channel state information-reference signal (CSI-RS) configuration information configured to a user equipment (UE), wherein the CSI-RS configuration information comprises information about a resource element (RE) occupied by a 16-port CSI-RS configured to the UE, and the RE occupied by the 16-port CSI-RS comprises an RE other than REs occupied by a physical downlink control channel (PDCCH), a cell-dedicated reference signal (RS) and a UE-dedicated RS; and sending, to the UE, the 16-port CSI-RS configuration information configured to the UE.