Multicast Precoding Optimization via Feedback

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current UMTS networks face challenges in providing high data rates and low latency for multimedia broadcast/multicast services due to interference and inefficient resource utilization, particularly in supporting multiple users with identical time-frequency resources.

Innovation Solution

A method that involves base stations sending broadcast or multicast service data to user equipment, receiving feedback on reception quality and precoding vector information, and using a coordination entity to optimize precoding vectors for beamforming and MU-MIMO transmission, improving spectral efficiency and reducing interference by adapting transmission parameters based on user equipment feedback.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Area of stationary object

If point-to-multipoint transmission is used to provide MBMS data to user equipments, then service coverage is improved, but interference increases and spectral efficiency deteriorates

Engineering Contradiction:
Improveservice coverageVSAvoidspectral efficiency
Core Design Contradiction:
Area of stationary objectVSLoss of energy

Solution Approach 1:

The patent applies local quality by configuring different transmission parameters (precoding vectors, resource blocks, power levels) for different spatial regions and user groups. The network dynamically adapts transmission characteristics to local channel conditions, user distribution, and interference environments, rather than using uniform parameters across the entire cell.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent implements dynamics through continuous adaptation of transmission parameters based on real-time feedback from user equipments. The network dynamically adjusts precoding vectors, resource allocation, and power control parameters in response to changing channel conditions, user mobility, and interference levels, transforming static transmission into a dynamic, responsive system.

Inventive Principle:
Principle #15Dynamics

2Productivity

If multiple users share identical time-frequency resources for MBMS reception, then resource utilization is improved, but interference between users increases

Engineering Contradiction:
Improveresource utilizationVSAvoidinterference
Core Design Contradiction:
ProductivityVSObject-generated harmful factors

Solution Approach 1:

The patent employs feedback mechanisms where user equipments report channel quality indicators, interference measurements, and reception status to the network. This feedback enables the network to adjust transmission parameters, reallocate resources, or modify precoding vectors to mitigate interference while maintaining efficient resource utilization for MBMS services.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The patent segments users into different groups or layers based on channel conditions, location, and service requirements. By dividing the user population into distinct segments, the network can apply differentiated transmission strategies, resource allocations, and interference management techniques to each segment, reducing overall interference while maintaining high resource utilization.

Inventive Principle:
Principle #1Segmentation

3Object-generated harmful factors

If beamforming is used to spatially separate transmissions, then interference is reduced, but system complexity increases

Engineering Contradiction:
ImproveinterferenceVSAvoidsystem complexity
Core Design Contradiction:
Object-generated harmful factorsVSDevice complexity

Solution Approach 1:

The patent introduces coordination entities and control mechanisms as intermediaries that manage beamforming operations. These intermediaries handle the complex calculations for precoding vector determination, coordinate multi-cell beamforming, and manage the interaction between transmission points and user equipments, thereby reducing the complexity burden on individual base stations while achieving effective spatial separation.

Inventive Principle:
Principle #24Intermediary (Mediator)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This approach enhances spectral efficiency, reduces interference, and optimizes data rates by spatially separating transmissions and adjusting transmission parameters to improve reception quality for multiple users, particularly those on the border of neighboring cells.

Implementation Method 1

Beamforming provides a practical means of supporting multiple users with signals transmitted at identical time-frequency resources. Thereby, especially beamforming with antenna arrays has shown to be able to achieve substantial capacity enhancements.

Methodology Applied
Scientific EffectBeamforming:

Implementation Method 2

Such multiple antennas have the potential to either increase the data rate through spatial multiplexing or enhance the quality of transmission through exploitation of diversity or beamforming.

Methodology Applied
Scientific EffectDiversity:

Implementation Method 3

receiving by the base stations feedbacks from the user equipments in response to the sent data, the feedbacks comprising user equipments reception quality information and/or precoding vector information

Methodology Applied
Scientific EffectFeedback: Feedback

Data Source

PatentEP2023502B1A method of providing a broadcast of multicast service in a digital wireless communication network
Publication Date: 2013.12.11 ALCATEL LUCENT SA
  • EP2023502B1 patent drawingFigure 1
  • EP2023502B1 patent drawingFigure 2
  • EP2023502B1 patent drawingFigure 3

AI summary

The invention relates to a method of providing a broadcast or multicast service to user equipments (UEs, 114; 116; 118; 120) in a digital wireless telecommunication network, the digital wireless telecommunication network comprising a set of antennas (102; 104) for providing the service to the user equipments (114; 116; 118; 120), the method comprising: - sending broadcast or multicast service data to the user equipments (114; 116; 118; 120), - receiving feedbacks from the user equipments (114; 116; 118; 120) in response to the sent data, the feedbacks comprising user equipment service data reception quality information and/or a precoding vector information, wherein the precoding vector information indicates for each of the user equipments (114; 116; 118; 120) a precoding vector for reception of the broadcast or multicast service, - determining an optimized precoding vector for transmitting the service to the user equipments (114; 116; 118; 120), wherein the determination of the optimized precoding vector is performed by analyzing the feedbacks.