TDD Carrier Aggregation Control Information Transmission

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Solution Overview

Problem

Current wireless communication systems face inefficiencies in transmitting and receiving control information, particularly in TDD-based systems with carrier aggregation, where resource allocation and signal processing methods are not optimized for efficient control information management.

Innovation Solution

A method and apparatus for a UE in a TDD-based wireless communication system that supports multiple carrier aggregation, employing specific channel formats, resource allocation schemes, and signal processing techniques to efficiently transmit and receive control information, including cross-carrier scheduling and subframe reconfiguration strategies to minimize resource loss and optimize link direction configurations.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If carrier aggregation with different UL-DL configurations is implemented, then system versatility and bandwidth utilization are improved, but control information transmission efficiency deteriorates due to resource allocation conflicts

Engineering Contradiction:
Improvecarrier aggregation supportVSAvoidcontrol information transmission efficiency
Core Design Contradiction:
Adaptability or versatilityVSProductivity

Solution Approach 1:

The patent segments control information transmission by defining separate PUCCH resource allocation mechanisms for different component carriers. Each CC's control information is handled independently through specific resource blocks and orthogonal codes, preventing interference between carriers with different UL-DL configurations and maintaining transmission efficiency.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent introduces cross-carrier scheduling as an additional dimension to resource allocation. Instead of allocating resources only within the same carrier, control information can be scheduled on different carriers, providing flexibility to resolve resource conflicts when carriers have different uplink-downlink configurations.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Quantity of substance

If multiple component carriers with different UL-DL configurations are aggregated, then bandwidth utilization is improved, but resource allocation complexity increases

Engineering Contradiction:
Improvebandwidth utilizationVSAvoidresource allocation complexity
Core Design Contradiction:
Quantity of substanceVSDevice complexity

Solution Approach 1:

The patent creates a universal PUCCH resource allocation framework that works across multiple component carriers with different UL-DL configurations. The same basic resource allocation principles and signaling mechanisms are applied universally, reducing the need for carrier-specific complex allocation schemes and simplifying overall resource management.

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Adaptability or versatility

If cross-carrier scheduling is implemented, then resource flexibility is improved, but signal processing complexity increases

Engineering Contradiction:
Improveresource flexibilityVSAvoidsignal processing complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent uses the PDCCH as an intermediary for cross-carrier scheduling. The PDCCH on one carrier can schedule resources on another carrier through carrier indicator fields (CIF), acting as a mediator that coordinates resource allocation across carriers without requiring direct complex interactions between all carrier pairs, thus managing signal processing complexity.

Inventive Principle:
Principle #24Intermediary (Mediator)

Data Source

PatentEP2770652B1Method and apparatus for transmitting control information in a wireless communication system
Publication Date: 2019.05.01 LG ELECTRONICS INC
  • EP2770652B1 patent drawingFigure 1
  • EP2770652B1 patent drawingFigure 2(a)~2(b)
  • EP2770652B1 patent drawingFigure 3

AI summary

The present invention relates to a wireless communication system. More particularly, the present invention relates to a method in which a terminal performs communication in a TDD-based wireless communication system having a plurality of CCs aggregated therein, the method comprising: a step of performing an uplink transmission or a downlink reception in each subframe on a first CC according to a first UL-DL configuration; and a step of performing an uplink transmission or a downlink reception in each subframe on a second CC according to a second UL-DL configuration. If the configuration of the subframe of the first CC is [U, D] and the configuration of the subframe of the second CC is [U, U] in sub frames #k and #k+1, the subframe #k+1 of the second CC is set to X. The present invention also relates to an apparatus for the method.