CSI Feedback Using Power-Offset Precoding in Multi-TRP Links

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Solution Overview

Problem

In multi-station coordination systems, inaccurate channel state information (CSI) feedback due to varying TRP powers degrades transmission performance.

Innovation Solution

A method for determining CSI by a terminal that adjusts channel estimation using multiple power offsets associated with reference signal resources, enabling an accurate precoding matrix matching actual transmission conditions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If multi-station coordination is used to improve throughput performance, then transmission capacity is improved, but CSI accuracy deteriorates due to different TRP powers

Engineering Contradiction:
Improvethroughput performanceVSAvoidCSI accuracy
Core Design Contradiction:
ProductivityVSMeasurement precision

Solution Approach 1:

The patent introduces power offset parameters to adjust the channel estimation process. By changing the parameter representation to include power offset information (PC,n) for each TRP, the system can compensate for power differences and maintain accurate CSI feedback while using multi-station coordination for improved throughput.

Inventive Principle:
Principle #35Parameter changes

2Device complexity

If channel estimation is performed without power offset adjustment, then processing complexity is reduced, but transmission performance deteriorates due to power mismatches

Engineering Contradiction:
Improveprocessing complexityVSAvoidtransmission performance
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The patent applies preliminary action by pre-calculating and storing power offset parameters (PC,n) for each TRP before channel estimation. This allows the channel estimation process to directly use these pre-computed parameters without adding complex real-time calculations, thus maintaining low processing complexity while improving transmission performance through accurate power compensation.

Inventive Principle:
Principle #10Preliminary action

3Measurement precision

If power offsets are considered in channel estimation, then CQI accuracy is improved, but calculation complexity increases

Engineering Contradiction:
ImproveCQI accuracyVSAvoidcalculation complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent changes the parameter representation by introducing power offset parameters (PC,n) that capture the power differences between TRPs. This parameter transformation simplifies the overall calculation by separating the power compensation aspect from the channel estimation, allowing accurate CQI calculation without proportionally increasing calculation complexity.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The power offset parameters are pre-determined and stored before the channel estimation and CQI calculation processes. This preliminary action eliminates the need for complex real-time power calculations during CQI determination, thus improving CQI accuracy while keeping the actual calculation complexity during operation low.

Inventive Principle:
Principle #10Preliminary action

Data Source

PatentEP4708715A1Channel state information determination method and apparatus
Publication Date: 2026.03.11 HUAWEI TECH CO LTD
  • EP4708715A1 patent drawingFigure 1~2
  • EP4708715A1 patent drawingFigure 3~5
  • EP4708715A1 patent drawingFigure 6

AI summary

This application provides a method for determining channel state information and an apparatus, relating to the field of communication technologies, to improve accuracy of CSI fed back by a terminal. In the method, a terminal may determine, based on a plurality of reference signals on a plurality of reference signal resources and a plurality of power offsets, a precoding matrix that matches a channel for actual transmission, so that a CQI obtained based on the precoding matrix conforms to channel quality of the channel for actual transmission. In other words, in this case, the terminal can obtain an accurate CQI, thereby improving accuracy of CSI fed back by the terminal to a network device, and improving transmission performance.