Sub-band Beam Reporting for Frequency Selective Scheduling

Solution Overview

Problem

Current beam management techniques in wireless communication systems are unable to determine the optimal TRP TX beam for specific sub-bands within a system bandwidth, preventing the combination of frequency selective scheduling with TX beam selection.

Innovation Solution

The UE measures and reports preferred TRP beams for each sub-band through frequency-selective CRI reporting, with the network node configuring the beam reporting procedure and transmitting sub-band-specific reference signals, allowing for sub-link-specific beam selection.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of information

If a single CRI report is transmitted for the entire bandwidth, then the reporting overhead is reduced, but the network node cannot determine the optimal TRP TX beam for specific sub-bands

Engineering Contradiction:

Core Design Contradiction:

Loss of informationVSDevice complexity

Solution Approach 1:

The system bandwidth is divided into multiple sub-bands, and the UE transmits separate CRI reports for each sub-band. This segmentation allows the network node to determine the optimal TRP TX beam for each specific sub-band, resolving the information loss problem while maintaining manageable reporting complexity through structured configuration.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different TRP TX beams are selected for different sub-bands based on local channel conditions. The UE measures reference signals in each sub-band and reports the preferred beam locally, enabling frequency-selective beam optimization rather than using a single beam for the entire bandwidth.

Inventive Principle:

Principle #3Local quality

2Productivity

If frequency selective scheduling is combined with sub-link-specific beam selection, then network capacity and coverage are improved, but the beam reporting overhead increases

Engineering Contradiction:

Core Design Contradiction:

ProductivityVSQuantity of substance

Solution Approach 1:

The network node pre-configures the beam reporting procedure, including sub-band definitions and reference signal assignments, before the UE performs measurements. This preliminary configuration allows efficient reporting of sub-band specific beam information without excessive overhead during actual operation.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The UE measures reference signals in each sub-band and provides feedback through CRI reports indicating the preferred TRP TX beam for each sub-band. This feedback mechanism enables the network node to adapt beam selection based on actual channel conditions, improving network capacity through informed scheduling decisions.

Inventive Principle:

Principle #23Feedback

Data Source

PatentUS10951297B2UE, network node and methods therein for beam reporting in a wireless communication system

Publication Date: 2021.03.16

AI summary

A method performed by a User Equipment (UE) is performed. The UE obtains (202) a beam reporting configuration. The beam reporting configuration defines a beam reporting procedure for determining an optimal beam for each of different sub-bands of a system bandwidth. The UE measures (204) different reference signals transmitted by the network node. The measured different reference signals correspond to each of the different sub-bands according to the beam reporting configuration. The UE then determines (206) a preferred beam for each of the different sub-bands based on the corresponding received reference signals.