Distributed Signal Classification for Cognitive Radio Interference

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

In wireless communication networks, multiple networks operating in the same frequency band often interfere with each other due to the inability to identify and adapt to other networks, leading to inefficient use of spectrum and potential disruptions.

Innovation Solution

A system and method for distributed signal classification in multi-hop cognitive communication devices, which includes a receiver to acquire digital samples, a feature extractor to identify signal features, and a classifier to determine signal types, allowing nodes to adapt their transmission methods to avoid interference by recognizing and classifying known and unknown networks.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If multiple networks operate in the same frequency band without signal classification, then spectrum utilization is high, but interference between networks increases

Engineering Contradiction:

Improvespectrum utilizationVSAvoidinterference

Core Design Contradiction:

ProductivityVSObject-affected harmful factors

Solution Approach 1:

The system performs signal classification and identification before transmission occurs. Each cognitive radio node classifies signals from other networks in advance, builds interference models, and determines appropriate transmission parameters beforehand, preventing interference rather than reacting to it

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system continuously monitors the wireless environment, classifies detected signals, and uses this information to adjust transmission parameters. The classification results feed back into the transmission decision-making process, creating a closed-loop system that adapts to changing conditions

Inventive Principle:

Principle #23Feedback

2Object-affected harmful factors

If handshaking techniques are used for spectrum access, then interference is reduced, but communication compatibility requirements increase

Engineering Contradiction:

ImproveinterferenceVSAvoidcommunication compatibility

Core Design Contradiction:

Object-affected harmful factorsVSAdaptability or versatility

Solution Approach 1:

The system introduces signal classification as an intermediary step between signal detection and transmission decision-making. Instead of requiring direct handshaking between networks, the classification mechanism mediates by identifying signal types and characteristics, enabling indirect coordination and reducing compatibility requirements

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The system replaces the mechanical handshaking protocol with an information-based classification approach. Rather than requiring direct communication and coordination between networks, the system uses signal feature analysis and classification to make transmission decisions independently

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Reliability

If secondary licensees verify operation by handshaking, then spectrum reversion is ensured, but operational complexity increases

Engineering Contradiction:

Improvespectrum reversionVSAvoidoperational complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The system enables secondary licensees to perform self-service by autonomously classifying signals and determining spectrum availability without requiring active handshaking with primary licensees. The cognitive radio nodes independently assess the environment and make transmission decisions while ensuring proper spectrum reversion

Inventive Principle:

Principle #25Self-service

4Adaptability or versatility

If cognitive radio technologies modify transmission methods based on interference, then coexistence is improved, but signal classification capability is required

Engineering Contradiction:

Improvetransmission adaptationVSAvoidsignal classification

Core Design Contradiction:

Adaptability or versatilityVSDifficulty of detecting and measuring

Solution Approach 1:

The system segments the signal classification process into distinct feature extraction components that analyze specific signal characteristics separately. By dividing the complex classification task into manageable feature analysis steps, the system reduces the difficulty of detecting and measuring signal properties

Inventive Principle:

Principle #1Segmentation

Data Source

PatentUS7742446B2System and method for performing distributed signal classification for a multi-hop cognitive communication device

Publication Date: 2010.06.22 RUCKUS IP HOLDINGS LLC

AI summary

A system and method for cognitive communication device operation. In accordance with the system and method, a node (102, 106, 107) that communicates in a wireless multihopping communication network (100) uses a receiver (302, 402, 502, 602) to acquire a digital sample of a communication signal, and extracts at least one feature of the digital sample. The node (102, 106, 107) employs a classifier (306, 406, 506) to determine the signal type, and a transmitter (108) to send feature vectors including information representing the signal type to other nodes (102, 106, 107) in the network (100).