Dynamic PHICH Resource Allocation in LTE TDD Systems

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Solution Overview

Problem

Current wireless communication systems, particularly in LTE, face challenges in flexibly allocating resources for the Physical Hybrid ARQ Indicator Channel (PHICH) due to fixed scheduling and limited information transmission capacity, which restricts the dynamic allocation of control channels, especially in Time Division Duplex (TDD) systems with fewer downlink subframes.

Innovation Solution

A method and apparatus for acquiring resource allocation of a control channel, where a user equipment (UE) receives a first resource allocation on a downlink channel in a subframe, acquires the resource region of the control channel, and then receives a second resource allocation on a third downlink channel indicated by the second downlink channel, allowing flexible allocation of PHICH resources and duration within each subframe, enabling more efficient use of control channel resources.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of information

If the resource region of PHICH is fixed in every subframe, then the information transmission overhead is reduced, but the flexibility of control channel allocation is degraded

Engineering Contradiction:
Improveinformation overheadVSAvoidflexibility of control channel allocation
Core Design Contradiction:
Loss of informationVSAdaptability or versatility

Solution Approach 1:

The patent applies dynamics by enabling the PHICH resource region to vary across different subframes rather than remaining fixed. The base station can dynamically adjust the resource allocation for PHICH in each subframe according to traffic conditions and system requirements, making the control channel allocation flexible and adaptive to changing network conditions.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent changes the parameter of PHICH resource region location from a fixed value to a variable that can be adjusted per subframe. By modifying the resource allocation parameters dynamically, the system achieves both reduced overhead (by not transmitting full resource information every subframe) and improved flexibility (by allowing resource adjustments when needed).

Inventive Principle:
Principle #35Parameter changes

2Adaptability or versatility

If the resource region of PHICH varies in every subframe, then the flexibility of control region allocation is improved, but the information transmission overhead increases

Engineering Contradiction:
Improveflexibility of control region allocationVSAvoidinformation overhead
Core Design Contradiction:
Adaptability or versatilityVSLoss of information

Solution Approach 1:

The patent segments the information transmission by separating the PHICH resource allocation information into different transmission layers. The resource region configuration is transmitted periodically or semi-persistently rather than in every subframe, while actual resource adjustments are indicated through compact signaling mechanisms, reducing the overall information overhead while maintaining flexibility.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent employs periodic action by transmitting PHICH resource region configuration information at specific intervals or in specific subframes rather than continuously in every subframe. This periodic transmission pattern reduces the information overhead significantly while still providing the necessary flexibility through timely updates when resource allocation changes are needed.

Inventive Principle:
Principle #19Periodic action

Data Source

PatentEP2255585B1Method and apparatus for acquiring resource allocation of control channel
Publication Date: 2019.05.08 LG ELECTRONICS INC
  • EP2255585B1 patent drawingFigure 1
  • EP2255585B1 patent drawingFigure 2~3
  • EP2255585B1 patent drawingFigure 4

AI summary

A method of acquiring a resource allocation of a control channel includes acquiring a resource region of the control channel in a second subframe based on a first resource allocation of the control channel, acquiring a resource region of a second downlink channel in the second subframe based on the resource region of the control channel, and receiving a second resource allocation of the control channel on a third downlink channel in the second subframe. The third downlink channel is indicated by the second downlink channel.