Relay Node Downlink Timing Synchronization via Base Station Commands

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

In LTE-A systems, downlink transmission between an eNB and an RN is not synchronized, lacking a solution for synchronization between the two.

Innovation Solution

A method and system where a base station transmits a downlink transmission timing adjustment command to a relay node, allowing the relay node to adjust its downlink transmission timing to synchronize with the base station's timing, ensuring synchronized downlink transmissions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If relay node transmits downlink signals independently without timing adjustment, then relay node can operate autonomously, but downlink transmission timing between eNB and relay node becomes unsynchronized

Engineering Contradiction:

Improverelay node autonomous operationVSAvoiddownlink transmission timing synchronization

Core Design Contradiction:

Ease of operationVSManufacturing precision

Solution Approach 1:

The eNB measures the timing of uplink signals received from the relay node and generates timing adjustment commands based on these measurements. These commands are fed back to the relay node to adjust its downlink transmission timing, creating a closed-loop feedback system that maintains synchronization while allowing autonomous operation.

Inventive Principle:

Principle #23Feedback

Solution Approach 2:

The relay node autonomously adjusts its own downlink transmission timing based on timing adjustment commands received from the eNB. The relay node independently applies the timing adjustment to synchronize its downlink transmissions with the eNB without requiring manual configuration or external intervention.

Inventive Principle:

Principle #25Self-service

2Manufacturing precision

If relay node adjusts downlink transmission timing to synchronize with eNB, then downlink transmission synchronization is achieved, but system complexity increases due to timing adjustment mechanisms

Engineering Contradiction:

Improvedownlink transmission timing synchronizationVSAvoidtiming adjustment system complexity

Core Design Contradiction:

Manufacturing precisionVSDevice complexity

Solution Approach 1:

The timing adjustment command is combined with the existing uplink grant structure. The eNB embeds the timing adjustment information within the uplink grant message that is already being transmitted to the relay node, merging the timing adjustment function with the existing uplink resource allocation mechanism to avoid adding separate complexity.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The uplink grant message serves multiple functions: it allocates uplink resources for the relay node and simultaneously conveys timing adjustment commands for downlink synchronization. This multi-functionality reduces system complexity by using an existing message structure for dual purposes rather than creating separate dedicated timing adjustment signaling.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Data Source

PatentUS9049706B2Method, device and system for relay timing adjustment

Publication Date: 2015.06.02 DATANG MOBILE COMM EQUIP CO LTD

AI summary

An embodiment of the present application provides a relay timing adjustment method, system and device, relating to the technical field of wireless communications, for use in solving the problem of how to synchronize base station downlink transmission and relay device downlink transmission in an Advanced Long Term Evolution (LTE-A) system. In this application, the base station sends an access downlink transmission timing adjustment command to the relay device. When the relay device receives said access downlink transmission timing adjustment command, the downlink transmission timing is adjusted in said relay device according to said received access downlink transmission timing adjustment command. This invention is thus able to synchronize relay device access downlink transmission timing with base station downlink transmission timing.