Cyclic Prefix Coordination for LTE D2D Interference

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

In LTE systems, D2D communication within cellular coverage experiences interference with cellular communication, and simultaneous performance of D2D and cellular communication has not been adequately addressed.

Innovation Solution

A terminal apparatus and base station apparatus system that exchanges and manages cyclic prefix information for inter-terminal signals, allowing efficient D2D communication by coordinating the cyclic prefix lengths for both D2D and uplink signals, enabling simultaneous operation without interference.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If D2D communication is performed within LTE coverage, then direct communication between terminal apparatuses is enabled, but interference occurs between cellular communication and D2D

Engineering Contradiction:

ImproveD2D communication efficiencyVSAvoidinterference between cellular communication and D2D

Core Design Contradiction:

ProductivityVSObject-affected harmful factors

Solution Approach 1:

The patent applies local quality by configuring different cyclic prefix lengths for different signal types. Specifically, the base station configures a first cyclic prefix length for D2D signals and a second cyclic prefix length for uplink signals, allowing each signal type to have optimized parameters suited to its specific requirements rather than using a uniform configuration for all signals.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent implements parameter changes by dynamically adjusting the cyclic prefix length parameter based on signal type. The base station transmits configuration information indicating different cyclic prefix lengths to the terminal apparatus, enabling the system to adapt parameters to reduce interference between D2D and cellular communications while maintaining communication efficiency.

Inventive Principle:

Principle #35Parameter changes

2Adaptability or versatility

If the terminal apparatus performs D2D and cellular communication simultaneously, then communication flexibility is improved, but resource coordination complexity increases

Engineering Contradiction:

Improvesimultaneous D2D and cellular communication capabilityVSAvoidresource coordination complexity

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent implements feedback mechanisms where the base station transmits configuration information about cyclic prefix lengths to the terminal apparatus. This feedback loop enables the base station to control and coordinate the resources used by the terminal apparatus for both D2D and cellular communications, simplifying the complexity of simultaneous operation through centralized management.

Inventive Principle:

Principle #23Feedback

Solution Approach 2:

The patent applies preliminary action by having the base station pre-configure the cyclic prefix lengths for different signal types before the terminal apparatus performs simultaneous D2D and cellular communications. This advance configuration simplifies the coordination process by establishing resource allocation parameters in advance rather than managing them dynamically during simultaneous operations.

Inventive Principle:

Principle #10Preliminary action

Data Source

PatentUS9680679B2Terminal apparatus and base station apparatus

Publication Date: 2017.06.13 SHARP KK

AI summary

First information indicating a length of a cyclic prefix for an inter-terminal apparatus signal transmitted to the other terminal apparatus and second information indicating a length of a cyclic prefix for an uplink signal in the EUTRAN, from a base station apparatus of the EUTRAN are received from a base station apparatus of the EUTRAN.