Uplink Throughput Optimization via Differential CQI Reporting

Solution Overview

Problem

In conventional radio communication systems, the large amount of data required for channel quality indicators (CQIs) transmitted from radio communication terminals to base stations consumes significant uplink channel resources, leading to deteriorated throughput and increased power consumption.

Innovation Solution

A method that measures the reception quality of multicarrier signals on a subcarrier basis, compares the results with a threshold value, and generates and transmits reception quality data with the smallest data amount, thereby reducing the data load and optimizing resource usage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If all subcarrier CQIs are transmitted to ensure complete channel quality information, then the base station can perform accurate adaptive modulation and scheduling, but the uplink channel resources are significantly consumed and throughput deteriorates

Engineering Contradiction:

Improvechannel quality information accuracyVSAvoiduplink throughput

Core Design Contradiction:

Measurement precisionVSProductivity

Solution Approach 1:

The patent extracts only the essential channel quality information needed for scheduling decisions. Instead of transmitting all 64 CQI values, the system identifies and transmits only the subcarrier indices and differential CQI values for subcarriers that differ from the reference subcarrier, thereby extracting the minimum necessary information to maintain scheduling accuracy while reducing overhead.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent applies partial action by transmitting CQI information for only a subset of subcarriers rather than all subcarriers. The system determines which subcarriers require explicit CQI reporting based on their deviation from the reference subcarrier, transmitting partial information that is sufficient for the base station to reconstruct the complete CQI profile for scheduling decisions.

Inventive Principle:

Principle #16Partial or excessive action

2Measurement precision

If all subcarrier CQIs are transmitted to maintain complete channel quality information, then accurate adaptive modulation can be performed, but power consumption increases and battery life decreases

Engineering Contradiction:

Improvechannel quality information accuracyVSAvoidpower consumption

Core Design Contradiction:

Measurement precisionVSUse of energy by moving object

Solution Approach 1:

The patent extracts only the essential channel quality information needed for scheduling decisions. Instead of transmitting all 64 CQI values, the system identifies and transmits only the subcarrier indices and differential CQI values for subcarriers that differ from the reference subcarrier, thereby extracting the minimum necessary information to maintain scheduling accuracy while reducing overhead.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent applies partial action by transmitting CQI information for only a subset of subcarriers rather than all subcarriers. The system determines which subcarriers require explicit CQI reporting based on their deviation from the reference subcarrier, transmitting partial information that is sufficient for the base station to reconstruct the complete CQI profile for scheduling decisions.

Inventive Principle:

Principle #16Partial or excessive action

3Productivity

If differential CQI encoding is used to reduce data amount, then uplink resources are released and throughput improves, but the complexity of encoding and decoding increases

Engineering Contradiction:

Improveuplink throughputVSAvoidencoding complexity

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

The patent changes the parameter representation by using differential encoding instead of absolute CQI values. The system encodes CQI as differences from a reference subcarrier value, transforming the data representation to reduce the number of bits required while maintaining the information content necessary for accurate channel quality assessment.

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS7881389B2Reception quality notifying method, wireless communication terminal apparatus, and base station apparatus

Publication Date: 2011.02.01 OPTIS WIRELESS TECHNOLOGY LLC

AI summary

A reception quality notifying method improves upstream-line throughput by reducing the data amount of reception quality data of downstream multicarrier signals to be transmitted in the upstream line. A low-power consumption base station apparatus and a wireless communication terminal apparatus may employ the reception quality notifying method. When a wireless communication terminal apparatus receives a downstream multicarrier signal and then notifies a base station apparatus of a subcarrier having a desirable reception quality for the downstream multicarrier signal, the wireless communication terminal apparatus produces reception quality data of a plurality of formats, then selects, from among the produced reception quality data, one having the lowest data mount. The selected reception quality data is transmitted to the base station apparatus by use of an upstream multicarrier signal subcarrier designated by the base station apparatus.