Doppler-Domain CSI Reporting for Time-Varying Channel Quality

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Solution Overview

Problem

Existing wireless communication systems fail to accurately account for time domain variations in channel state information (CSI) due to extrapolated measurement information that does not reflect changes in channel quality, leading to potential inaccuracies in network scheduling and inefficient resource utilization.

Innovation Solution

A user equipment (UE) is configured to report Doppler domain CSI with parameters indicating time domain variations, allowing for more accurate CSI reporting by transmitting wideband CQI and subband differential CQI values, thereby maintaining power savings while improving reporting accuracy.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If CSI report bundling is used to save power, then power consumption is reduced, but time domain variations in channel quality are not accurately reflected

Engineering Contradiction:

Improvepower consumptionVSAvoidchannel quality accuracy

Core Design Contradiction:

Use of energy by moving objectVSMeasurement precision

Solution Approach 1:

The CQI report is segmented into a wideband CQI component and multiple subband differential CQI components. The wideband CQI provides overall channel quality information, while the subband differential CQI values capture time domain variations across different frequency subbands. This segmentation allows the system to maintain power efficiency through bundling while accurately representing temporal channel variations.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent changes the parameter representation by using differential CQI values relative to a reference subband rather than absolute CQI values for each subband. This parameter transformation reduces the information overhead while preserving time domain variation information, enabling accurate channel quality reporting with reduced power consumption.

Inventive Principle:

Principle #35Parameter changes

2Measurement precision

If detailed CSI reporting is performed for each subband, then channel quality accuracy is improved, but transmission overhead increases

Engineering Contradiction:

Improvechannel quality accuracyVSAvoidtransmission overhead

Core Design Contradiction:

Measurement precisionVSQuantity of substance

Solution Approach 1:

Instead of transmitting full absolute CQI values for each subband, the patent transmits differential CQI values that represent deviations from a reference subband. This copying approach uses the reference subband as a baseline and only transmits the differences, significantly reducing transmission overhead while maintaining accurate channel quality information for all subbands.

Inventive Principle:

Principle #26Copying

Solution Approach 2:

The patent transforms the CQI reporting parameters from absolute values to differential values. By reporting changes relative to a reference point rather than complete absolute values, the system reduces the number of bits required for transmission while preserving the ability to accurately represent channel quality across all subbands.

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS20260019121A1Reporting design for doppler domain channel state information

Publication Date: 2026.01.15 QUALCOMM INC

AI summary

Certain aspects of the present disclosure provide a method for wireless communication by a user equipment (UE). generally including receiving. from a network entity. a configuration for Doppler domain channel state information (CSI) reporting. measuring channel state information (CSI) based on a bundle of CSI reference signal (CSI-RS) occasions, and transmitting. in accordance with the configuration. a report for Doppler domain CSI that includes parameters that indicate time domain variations of the measured CSI.