Implicit Resource Allocation via Shifted Synchronization Sequences

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In unlicensed shared band communication systems, ensuring effective asynchronous and contention-based access with dynamic and scalable spectrum allocation is challenging due to unpredictable interference and lack of guaranteed quality of service, particularly in scenarios where communication devices lack a common timing reference.

Innovation Solution

The method involves transmitting a first synchronization signal with a first cyclic shift over a shared band to synchronize communication devices, and mapping a second cyclic shift to resources of channels, with a second synchronization signal indicating the resources used for data transmission, allowing for simultaneous synchronization and resource allocation without an explicit control channel.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a common timing reference is used for synchronization, then synchronization accuracy is improved, but device complexity and system coordination requirements increase

Engineering Contradiction:
Improvesynchronization accuracyVSAvoidsystem coordination requirements
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

Each communication device independently determines timing information by detecting cyclic shifts in synchronization signals from other devices, without requiring a central timing reference or complex inter-device coordination mechanisms. The device self-synchronizes by measuring time offsets between received and transmitted synchronization signals.

Inventive Principle:
Principle #25Self-service

2Productivity

If cyclic shifts are mapped to channel resources, then resource allocation efficiency is improved, but signal detection complexity increases

Engineering Contradiction:
Improveresource allocation efficiencyVSAvoidsignal detection complexity
Core Design Contradiction:
ProductivityVSDifficulty of detecting and measuring

Solution Approach 1:

Different cyclic shifts of the synchronization signal correspond to different channel resources, creating a mapping relationship similar to color coding. The receiving device determines which channel resource was allocated by detecting which cyclic shift variant is present in the received signal, enabling resource identification through signal characteristic detection.

Inventive Principle:
Principle #32Color changes

3Adaptability or versatility

If multiple synchronization signals with different cyclic shifts are transmitted, then resource allocation capability is improved, but interference in unlicensed bands increases

Engineering Contradiction:
Improveresource allocation capabilityVSAvoidinterference in unlicensed bands
Core Design Contradiction:
Adaptability or versatilityVSObject-generated harmful factors

Solution Approach 1:

The synchronization signal is segmented into multiple cyclic shift variants, each representing different channel resource allocations. By transmitting different cyclic shift versions rather than multiple full synchronization signals, the system achieves resource allocation capability while reducing overall signal power and interference in the unlicensed band environment.

Inventive Principle:
Principle #1Segmentation

Data Source

PatentEP2647251B1Implicit resource allocation using shifted synchronization sequence
Publication Date: 2019.07.24 NOKIA TECHNOLOGIES OY
  • EP2647251B1 patent drawingFigure 1
  • EP2647251B1 patent drawingFigure 2
  • EP2647251B1 patent drawingFigure 3

AI summary

A method, apparatus, system, and computer readable medium are provided that can utilize one or more synchronization signals to perform synchronization and resource allocation. The one or more synchronization signals can be used for synchronization, as well as include a cyclic shift that maps one or more resources for transmission.