Compressed CSI Feedback for Massive MIMO Channel Recovery

Solution Overview

Problem

In massive MIMO systems operating at millimeter wave frequencies, the acquisition of accurate channel state information (CSI) is hindered by the large overhead of transmitting and feedbacking CSI reference signals, especially as the number of antenna ports increases, leading to inefficiencies in beamforming and precoding design.

Innovation Solution

A method involving the transmission of CSI reference signals from a network device to a terminal device, where the terminal device compresses the CSI based on its capabilities and feeds it back to the network device for recovery, utilizing machine learning mechanisms to enhance CSI acquisition with reduced complexity and overhead, allowing for more accurate CSI recovery with a limited number of ports.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the number of antenna ports is increased to improve system capacity and throughput, then the beamforming and precoding performance is improved, but the overhead of transmitting and feedbacking CSI reference signals increases significantly

Engineering Contradiction:

Improvesystem throughputVSAvoidCSI feedback overhead

Core Design Contradiction:

ProductivityVSQuantity of substance

Solution Approach 1:

The patent extracts only the essential CSI parameters needed for beamforming and precoding from the complete CSI set. By identifying and retaining only the critical components (such as dominant eigenvectors and corresponding singular values) while discarding redundant information, the system achieves accurate channel state representation with significantly reduced feedback overhead, directly resolving the contradiction between system capacity and overhead.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent creates a compressed representation (copy) of the complete CSI that captures the essential characteristics needed for beamforming and precoding. This compressed CSI copy contains sufficient information for accurate channel state representation but occupies minimal feedback resources, allowing the system to maintain high throughput while reducing overhead.

Inventive Principle:

Principle #26Copying

2Measurement precision

If the complete CSI is transmitted to ensure accurate channel state information, then the beamforming and precoding accuracy is improved, but the feedback overhead and power consumption increase

Engineering Contradiction:

ImproveCSI accuracyVSAvoidterminal device power consumption

Core Design Contradiction:

Measurement precisionVSUse of energy by moving object

Solution Approach 1:

The patent extracts only the essential CSI parameters needed for beamforming and precoding from the complete CSI set. By identifying and retaining only the critical components (such as dominant eigenvectors and corresponding singular values) while discarding redundant information, the system achieves accurate channel state representation with significantly reduced feedback overhead, directly resolving the contradiction between system capacity and overhead.

Inventive Principle:

Principle #2Taking out (Extraction)

3Measurement precision

If the complete CSI is transmitted to ensure accurate channel state information, then the beamforming and precoding accuracy is improved, but the feedback overhead increases

Engineering Contradiction:

ImproveCSI accuracyVSAvoidfeedback overhead

Core Design Contradiction:

Measurement precisionVSQuantity of substance

Solution Approach 1:

The patent extracts only the essential CSI parameters needed for beamforming and precoding from the complete CSI set. By identifying and retaining only the critical components (such as dominant eigenvectors and corresponding singular values) while discarding redundant information, the system achieves accurate channel state representation with significantly reduced feedback overhead, directly resolving the contradiction between system capacity and overhead.

Inventive Principle:

Principle #2Taking out (Extraction)

Data Source

PatentUS12101142B2Method, device and computer readable medium of communication

Publication Date: 2024.09.24 NOKIA TECHNOLOGIES OY

AI summary

Embodiments of the present disclosure relate to methods, devices and computer readable storage media of communication. A network device transmits, to a terminal device, channel state information reference signals associated with first number of ports at the network device; receives, from the terminal device, compressed channel state information generated based on capability of the terminal device; and recoveries, from the compressed channel state information, channel state information associated with second number of ports at the network device, the second number of ports being not less than the first number of ports. The terminal device receives, from the network device, the channel state information reference signals associated with the first number of ports at the network device; determines channel state information based on the channel state information reference signals; compresses the channel state information based on capability of the terminal device; and transmits the compressed channel state information to the network device for recovery of the channel state information associated with the second number of ports. As such, CSI can be acquired more accurately with reduced complexity and overhead.