Ethernet Microphonic Isolation via Optical Conversion

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing communication devices often unintentionally transmit microphonic signals, which can compromise secure data communications by allowing sensitive information to be intercepted outside secure locations, particularly in environments where standards like TSG Standard No. 5 require minimal audio transmission even when devices are in an idle state.

Innovation Solution

A microphonic isolation system that filters out unwanted audio frequency signals (20 Hz to 20 kHz) from data transmission lines using an isolation device with a filter and optical isolation circuit, ensuring only data signals are passed through, thereby preventing unintended audio transmissions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a communication device is placed in a secure location with Ethernet wiring, then data communication capability is provided, but microphonic signals can be transmitted through the wiring compromising security

Engineering Contradiction:

Improvedata communication capabilityVSAvoidmicrophonic signal transmission

Core Design Contradiction:

Adaptability or versatilityVSObject-affected harmful factors

Solution Approach 1:

An optical isolator is introduced as an intermediary device between the Ethernet communication device and the network wiring. The isolator converts electrical signals to optical signals and back, breaking the direct electrical connection while maintaining data communication. This mediator prevents microphonic signals from coupling onto the wiring while preserving the intended data transmission function.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent replaces the direct electrical connection system with an optical signal transmission system. By using light instead of electrical signals for isolation, the system eliminates the electromagnetic coupling that allows microphonic interference to propagate through the wiring, while maintaining communication capability through optical conversion.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Object-affected harmful factors

If filtering components are added to remove microphonic signals, then security is improved, but device complexity increases

Engineering Contradiction:

Improvemicrophonic signal blockingVSAvoidisolation device structure

Core Design Contradiction:

Object-affected harmful factorsVSDevice complexity

Solution Approach 1:

The optical isolator serves as a compact intermediary device that integrates multiple functions (signal conversion, isolation, and filtering) into a single component. This approach reduces overall system complexity compared to using separate filtering components, as the optical conversion inherently provides both isolation and microphonic signal rejection.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

Replacing complex electrical filtering circuits with an optical isolation device simplifies the system architecture. The optical isolator provides microphonic signal blocking through its fundamental operating principle of optical-electrical conversion, eliminating the need for additional complex filtering hardware and reducing overall device complexity.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The system effectively isolates microphonic signals from data signals, enabling secure communication devices to comply with standards like TSG Standard No. 5 by preventing unwanted audio transmissions, even when devices are in an idle state, thus maintaining secure data communication.

Implementation Method 1

Some embodiments of the isolation device include an optical isolator

Methodology Applied

Scientific EffectOptical isolation: Optical Fibre

Implementation Method 2

The filter is arranged to substantially remove the microphonic signal received at the input from first part of transmission line and pass the data signal to the output

Methodology Applied

Scientific EffectFrequency filtering: Filter (electronic)

Data Source

PatentUS8199922B2Ethernet isolator for microphonics security and method thereof

Publication Date: 2012.06.12 AVAYA INC

AI summary

A system and method for providing microphonic isolation on a transmission line. The transmission line has a first part and a second part. The first part of transmission line carries a data signal and a microphonic signal. The microphonic signal has frequencies that include those in a range of substantially 20 Hz to substantially 20 kHz. The system includes an isolation apparatus. The isolation apparatus has an input in electrical communication with a first part of the transmission line, an output in electrical communication with the second part of the transmission line, and a filter in electrical communication with the input and the output. The filter is arranged to substantially remove the microphonic signal received at the input from first part of transmission line and pass the data signal to the output.