Multihop Relay Scheduling via Distributed CQI Reporting

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Solution Overview

Problem

Current wireless communication systems with multihop relay face challenges in efficiently scheduling and power controlling data transmission across relay stations, which affects the quality of service for multimedia services, particularly in supporting high data transmission rates and ensuring reliable communication.

Innovation Solution

The implementation of distributed and centralized scheduling and power control methods within the wireless communication system, where relay stations estimate and report channel quality indicators (CQI) to base stations and subscriber stations, allowing for optimized resource allocation and transmission power adjustments across multiple hops.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If distributed scheduling and power control methods are implemented in multihop relay systems, then data transmission rate and communication reliability are improved, but system complexity and coordination overhead increase

Engineering Contradiction:
Improvedata transmission rateVSAvoidscheduling coordination complexity
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The patent divides the multihop relay system into multiple independent scheduling domains, where each relay station autonomously performs scheduling and power control for its own downstream links. This segmentation eliminates the need for complex centralized coordination while maintaining high data transmission rates through localized optimization.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Each relay station is equipped with autonomous scheduling and power control capabilities, allowing it to independently make transmission decisions based on local channel conditions. This self-service approach removes dependency on centralized control, reducing system complexity while preserving productivity through adaptive local decision-making.

Inventive Principle:
Principle #25Self-service

2Adaptability or versatility

If relay stations autonomously perform scheduling and power control, then system responsiveness and adaptability improve, but computational load and energy consumption at relay stations increase

Engineering Contradiction:
Improvesystem adaptabilityVSAvoidrelay station energy consumption
Core Design Contradiction:
Adaptability or versatilityVSUse of energy by moving object

Solution Approach 1:

The patent implements partial autonomy where relay stations perform scheduling and power control only for their immediate downstream links rather than entire multihop paths. This partial action provides sufficient adaptability for local optimization while limiting computational load and energy consumption at each relay station.

Inventive Principle:
Principle #16Partial or excessive action

Solution Approach 2:

Each relay station optimizes transmission parameters locally based on its specific channel conditions and traffic requirements, rather than participating in global optimization. This local quality approach enhances adaptability to local conditions while minimizing the energy and computational resources required at each node.

Inventive Principle:
Principle #3Local quality

3Productivity

If centralized control is used for scheduling and power control, then system-wide optimization is achieved, but coordination overhead and latency increase

Engineering Contradiction:
Improvesystem throughputVSAvoidcoordination latency
Core Design Contradiction:
ProductivityVSLoss of time

Solution Approach 1:

The patent segments the centralized control function into distributed autonomous operations at each relay station. By eliminating the need for continuous centralized coordination and feedback loops, the system achieves comparable throughput while dramatically reducing coordination latency through localized decision-making.

Inventive Principle:
Principle #1Segmentation

4Area of stationary object

If more relay stations are added to extend coverage, then coverage area and reliability improve, but system complexity and interference management difficulty increase

Engineering Contradiction:
Improvecoverage areaVSAvoidrelay station management complexity
Core Design Contradiction:
Area of stationary objectVSDevice complexity

Solution Approach 1:

The patent segments the multihop relay system into independent transmission hops, where each relay station manages only its immediate downstream link. This segmentation allows arbitrary extension of coverage area through additional relay stations while keeping management complexity localized and bounded at each node.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Each relay station autonomously adjusts transmission parameters such as power level and scheduling decisions based on local channel conditions. This parameter adaptation at each hop enables scalable system expansion without proportionally increasing overall system complexity, as each node operates independently with localized parameter optimization.

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP2663003B1Data transmission and power control in a multihop relay communication system
Publication Date: 2022.06.29 QUALCOMM INC
  • EP2663003B1 patent drawingFigure 1
  • EP2663003B1 patent drawingFigure 2
  • EP2663003B1 patent drawingFigure 3

AI summary

Techniques for transmitting data with distributed and centralized scheduling in a multihop relay communication system are described. For distributed scheduling, a relay station may generate and send first channel quality information (CQI) to a base station and receive second CQI from a subscriber station. The relay station may receive data sent by the base station based on the first CQI and may resend the data to the subscriber station based on the second CQI. For centralized scheduling, the relay station may generate first CQI for the base station, receive second CQI from the subscriber station, and send both CQIs to the base station. The relay station may receive data sent by the base station based on the first CQI and may resend the data to the subscriber station based on a scheduling decision determined based on the second CQI.; Techniques for distributed and centralized power control are also described.