CSI Determination Using Multi-Period Reference Signals

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Solution Overview

Problem

The existing Massive MIMO technology faces inefficiencies in updating and reporting channel state information (CSI) due to the need for frequent pilot signals, leading to CSI aging and reduced system performance.

Innovation Solution

A method involving sending at least two reference signals with varying periodicities, allowing the network device to determine CSI based on a first reference signal with a shorter periodicity, thereby reducing the need for waiting for subsequent signals and alleviating CSI aging.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If the terminal waits for the second reference signal to report CSI, then the CSI accuracy is improved, but the reporting delay increases and CSI aging occurs

Engineering Contradiction:

ImproveCSI accuracyVSAvoidCSI reporting delay

Core Design Contradiction:

Measurement precisionVSLoss of time

Solution Approach 1:

The terminal performs preliminary CSI measurement and calculation based on the first reference signal before the second reference signal arrives. The calculated CSI is temporarily stored and will replace the CSI based on the second reference signal when the terminal determines that the channel conditions remain stable, thus avoiding the need to wait for the second reference signal and reducing reporting delay.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system dynamically selects between using CSI from the first reference signal or CSI from the second reference signal based on channel stability assessment. When channel conditions are stable, the terminal uses the earlier CSI from the first reference signal; when channel conditions change significantly, the terminal uses the updated CSI from the second reference signal, thus adaptively optimizing the balance between accuracy and timeliness.

Inventive Principle:

Principle #15Dynamics

2Productivity

If the terminal uses CSI from the first reference signal, then the reporting timeliness is improved, but the CSI accuracy may deteriorate

Engineering Contradiction:

ImproveCSI reporting efficiencyVSAvoidCSI accuracy

Core Design Contradiction:

ProductivityVSMeasurement precision

Solution Approach 1:

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The terminal assesses channel stability by comparing channel conditions between the first and second reference signals. Based on this feedback assessment, the terminal determines whether to use the earlier CSI from the first reference signal or the updated CSI from the second reference signal, thus adaptively optimizing the balance between reporting timeliness and CSI accuracy.

Inventive Principle:

Principle #23Feedback

3Productivity

If multiple reference signals are sent with different periodicities, then the CSI updating efficiency is improved, but the system complexity increases

Engineering Contradiction:

ImproveCSI updating efficiencyVSAvoidreference signal configuration complexity

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

The reference signals are segmented into different types with different functions: the first reference signal is used for preliminary CSI measurement with higher periodicity, while the second reference signal is used for verification and update with lower periodicity. This segmentation allows the system to optimize CSI updating efficiency without requiring all reference signals to have the same configuration, thus managing complexity through functional differentiation.

Inventive Principle:

Principle #1Segmentation

Data Source

PatentEP4716105A1Channel state information determination method and apparatus

Publication Date: 2026.03.25 HUAWEI TECH CO LTD

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AI summary

A channel state information determining method and apparatus are provided, and relate to the wireless communication field. In the method, a network device sends at least two reference signals including a first reference signal and a second reference signal, and receives first information. The first information indicates that a part or all of information in CSI corresponding to the second reference signal is determined based on the first reference signal. A sending periodicity of the first reference signal is less than a sending periodicity of the second reference signal. According to the foregoing design, the network device can be enabled to efficiently obtain the CSI.