Mobile Station PUCCH Resource Management in Carrier Aggregation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In LTE-A systems, there is a shortage of PUCCH resources in primary cells, especially in scenarios like macro cells configured for voice traffic, and inconsistencies in the activation/deactivation state of secondary cells lead to issues with handling uplink control information in secondary cells.

Innovation Solution

The solution involves supporting PUCCH transmission in secondary cells, with approaches such as reserving PUCCH resources in other cells, stopping transmission in deactivated secondary cells, providing notifications for state inconsistencies, and preventing secondary cells from transitioning to deactivation states, allowing uplink control information to be transmitted in primary or activated secondary cells.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If PUCCH transmission is supported only in primary cell, then uplink control information can be transmitted reliably, but PUCCH resources become insufficient in primary cells with many mobile stations

Engineering Contradiction:
Improveuplink control information transmissionVSAvoidPUCCH resources
Core Design Contradiction:
ReliabilityVSQuantity of substance

Solution Approach 1:

The patent segments the PUCCH transmission function by enabling it in both primary cells and secondary cells. This divides the previously concentrated PUCCH resource demand in primary cells into distributed resources across multiple cells, thereby increasing total PUCCH resource availability while maintaining reliable uplink control information transmission through multiple potential transmission paths.

Inventive Principle:
Principle #1Segmentation

2Loss of energy

If secondary cell is deactivated to save resources, then resource consumption is reduced, but inconsistency occurs between base station and mobile station about cell state

Engineering Contradiction:
Improveresource consumptionVSAvoidcell state consistency
Core Design Contradiction:
Loss of energyVSLoss of information

Solution Approach 1:

The patent implements a feedback mechanism where the mobile station detects PUCCH transmission opportunities in secondary cells and notifies the base station of the actual cell state. This feedback loop allows the base station to update its understanding of the secondary cell state, resolving inconsistencies between base station and mobile station perspectives while enabling resource-efficient deactivation when appropriate.

Inventive Principle:
Principle #23Feedback

3Quantity of substance

If secondary cell is activated for PUCCH transmission, then PUCCH resources are increased, but device complexity increases due to state management

Engineering Contradiction:
ImprovePUCCH resourcesVSAvoidactivation/deactivation state management
Core Design Contradiction:
Quantity of substanceVSDevice complexity

Solution Approach 1:

The patent enables the mobile station to autonomously detect PUCCH transmission opportunities in secondary cells and self-manage the notification process to the base station. This self-service approach allows the system to dynamically adapt PUCCH resource availability without requiring complex centralized state management, reducing device complexity while increasing PUCCH resource capacity.

Inventive Principle:
Principle #25Self-service

Data Source

PatentEP3182789B1Mobile station and control method
Publication Date: 2018.07.11 NTT DOCOMO INC
  • EP3182789B1 patent drawingFigure 1
  • EP3182789B1 patent drawingFigure 2
  • EP3182789B1 patent drawingFigure 3

AI summary

There is provided a mobile station for communication using carrier aggregation, comprising: a reception unit configured to receive an instruction from a base station to transition a secondary cell to a deactivation state; and a transition instruction control unit configured to discard the instruction received by the reception unit, when the instruction received by the reception unit is an instruction for a secondary cell in which transmission of a physical uplink control channel is supported.