CQI Compensation for PRB Blocking in E-FCB Scheduling

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Solution Overview

Problem

CQI reports from user equipment (UE) are inaccurate due to blocking of physical resource blocks (PRBs) causing muting of downlink control channels and reference signals, leading to inaccurate channel quality estimation and reduced signal-to-noise ratio (SNR), which affects transmission performance in Enhanced Flexible Channel Bandwidth (E-FCB) operations.

Innovation Solution

A network node compensates the reported CQI values by calculating a compensated SINR value based on the proportion of blocked PRBs, using mapping tables to adjust transmission parameters such as modulation and coding schemes, thereby improving CQI accuracy and enhancing throughput.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If physical resource blocks are blocked to allow spectrum overlap between RATs, then spectrum utilization is improved, but channel quality estimation accuracy deteriorates

Engineering Contradiction:

Improvespectrum utilizationVSAvoidchannel quality estimation accuracy

Core Design Contradiction:

Adaptability or versatilityVSMeasurement precision

Solution Approach 1:

The network node pre-calculates and stores compensation values in mapping tables before CQI reporting occurs. These tables map the relationship between blocked PRB proportions and CQI compensation values, allowing the UE to directly lookup and apply compensation without complex real-time calculations, thus restoring measurement accuracy while maintaining spectrum flexibility

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The invention transforms the CQI value by applying a compensation parameter derived from the blocked PRB proportion. The network node determines the proportion of blocked PRBs and uses mapping tables to find the appropriate compensation value, then adds this to the reported CQI to obtain a compensated CQI that accurately reflects channel quality despite PRB blocking

Inventive Principle:

Principle #35Parameter changes

2Adaptability or versatility

If downlink control channels and reference signals are muted due to PRB blocking, then spectrum flexibility is improved, but signal-to-noise ratio deteriorates

Engineering Contradiction:

Improvespectrum flexibilityVSAvoidsignal-to-noise ratio

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The invention converts the harmful effect of PRB blocking (which mutes control channels and reference signals, reducing measured SNR) into a beneficial outcome by calculating compensation values based on the blocked PRB proportion. The network node uses the known blocking pattern to determine how much the CQI should be compensated, effectively converting the negative impact into a correctable parameter that restores accurate channel quality assessment

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

3Measurement precision

If CQI reports are adjusted to compensate for PRB blocking, then channel quality accuracy is improved, but computational complexity increases

Engineering Contradiction:

Improvechannel quality accuracyVSAvoidcomputational complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The mapping table serves as an intermediary between the blocked PRB proportion and the CQI compensation value. Instead of requiring complex real-time calculations, the system uses the pre-computed mapping table to translate the blocking scenario into the appropriate compensation, simplifying the computational burden while maintaining accuracy

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentEP4578125B1Handling of CQI reports in the presence of PRB blocking

Publication Date: 2025.12.03 TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)

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AI summary

There is provided techniques for selecting transmission parameters for a user equipment. A method is performed by a network node. The method comprises receiving a channel quality report from a user equipment served by a communication network where a portion of PRBs is blocked with muting of DL control channels and reference signals. The channel quality report comprises a CQI value. The method comprises obtaining a compensated SINR value for the user equipment from the CQI value as compensated due to downgrade caused by the DL control channels and reference signals being muted. The CQI value is compensated as a function of how large the blocked portion of PRBs is. The method comprises selecting the transmission parameters for the user equipment as a function of the compensated SINR value.