Aperiodic CSI Reporting for Static and Flexible Subframes

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current wireless communication networks face challenges in handling separate Channel State Information (CSI) measurements for static and flexible subframes in TDD systems, leading to interference issues due to unpredictable UE-to-UE interference during flexible subframes, which affects data transmission reliability and efficiency.

Innovation Solution

A method is introduced to trigger User Equipment (UE) to perform separate aperiodic CSI reporting for static and flexible subframes by using specific triggers in uplink grants, allowing for distinct CSI measurements and reports for each type of subframe, thereby enabling better interference management and dynamic resource allocation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If separate aperiodic CSI reporting for static and flexible subframes is implemented, then CSI reporting accuracy is improved and interference is reduced, but device complexity and signaling overhead increase

Engineering Contradiction:

ImproveCSI reporting accuracyVSAvoidUE and radio node complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent segments the CSI reporting process by introducing separate trigger mechanisms for static and flexible subframes. The radio node sends distinct triggers (e.g., different CSI request field values in DCI) to request CSI reports specifically for static subframes or flexible subframes, allowing the UE to perform and report CSI measurements separately for each subframe type, thereby improving measurement precision while managing complexity through structured segmentation

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent implements dynamic triggering mechanisms where the radio node can flexibly decide when to request CSI reports for static or flexible subframes based on current network conditions and interference scenarios. The trigger timing and target subframe selection are dynamically adjusted, allowing the system to adapt to changing conditions while maintaining separate reporting channels for different subframe types

Inventive Principle:

Principle #15Dynamics

2Object-affected harmful factors

If separate aperiodic CSI reporting for static and flexible subframes is implemented, then interference management is improved, but signaling overhead increases

Engineering Contradiction:

ImproveinterferenceVSAvoidsignaling overhead

Core Design Contradiction:

Object-affected harmful factorsVSLoss of substance

Solution Approach 1:

The patent applies partial action by selectively triggering CSI reports only when needed for specific subframe types. Instead of requiring continuous separate reporting for both static and flexible subframes, the radio node triggers reports partially based on current interference conditions and scheduling needs, reducing unnecessary signaling overhead while maintaining effective interference management when required

Inventive Principle:

Principle #16Partial or excessive action

Solution Approach 2:

The patent applies local quality by allowing different CSI reporting behaviors for different subframe types based on their specific characteristics. Static subframes use one reporting mechanism while flexible subframes use another, with each optimized for its specific interference profile and usage pattern, rather than applying a uniform reporting approach across all subframes

Inventive Principle:

Principle #3Local quality

3Productivity

If dynamic TDD reconfigurations are performed with separate CSI measurements, then network capacity and performance are enhanced, but system complexity increases

Engineering Contradiction:

Improvenetwork capacityVSAvoidsystem complexity

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

The patent segments the TDD reconfiguration process by maintaining separate CSI measurement and reporting chains for static and flexible subframes. This segmentation allows the system to handle dynamic reconfigurations more effectively by having dedicated CSI feedback for each subframe type, enabling better capacity optimization while managing complexity through structured separation of measurement processes

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent implements enhanced feedback mechanisms where separate CSI reports for static and flexible subframes provide the radio node with more granular channel state information. This detailed feedback enables more accurate and efficient dynamic TDD reconfigurations, allowing the system to optimize network capacity by making informed decisions based on separate CSI measurements for different subframe types

Inventive Principle:

Principle #23Feedback

Data Source

PatentUS11659428B2Method and radio node for handling CSI reporting

Publication Date: 2023.05.23 TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)

AI summary

A radio node and a UE are described, and methods and computer programs therein to handle separate aperiodic CSI reports for one or more static subframes, in which the direction of signal transmission is fixed, and one or more flexible subframes, in which the direction of signal transmission is variable. The method performed by a UE comprises receiving a trigger for an aperiodic CSI report as part of an uplink grant from a radio node in a static downlink subframe, said trigger indicating a CSI subframe set related to the one or more static subframes. The method further comprises reporting to the radio node, in a CSI reporting subframe, a result of an aperiodic CSI measurement for a CSI reference in the CSI subframe set. The method further comprises receiving a second trigger that relates to the one or more flexible subframes and reporting the results to the radio node.