Analog EMI Cancellation for Ethernet Transceivers

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current Ethernet systems face link failures due to insufficient electromagnetic interference (EMI) protection, leading to signal distortion and increased transceiver complexity, cost, and power consumption, as EMI is not effectively mitigated in the analog domain.

Innovation Solution

Analog cancellation signals are generated and summed with receive signals to mitigate EMI, reducing transceiver complexity and cost by suppressing EMI in the analog domain, allowing for better link operation across a wider bandwidth.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If EMI protection is provided by shielding and differential transmission, then EMI immunity is improved, but device complexity and cost increase

Engineering Contradiction:

ImproveEMI immunityVSAvoidtransceiver complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent replaces mechanical/physical EMI protection methods (shielding, differential transmission) with an electrical signal processing approach. An analog cancellation signal is generated and summed with the receive signal to actively cancel EMI, substituting passive physical protection with active electrical correction.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent introduces an intermediary analog cancellation signal that acts as a mediator between the EMI disturbance and the receive signal. This cancellation signal is derived from the receive signal itself and serves as an intermediate element to actively counteract the EMI before it causes link failure.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If digital EMI mitigation is implemented, then EMI suppression capability is improved, but transceiver area and power consumption increase

Engineering Contradiction:

ImproveEMI suppression capabilityVSAvoidpower consumption

Core Design Contradiction:

ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent substitutes digital EMI mitigation processing with an analog domain solution. By generating and summing an analog cancellation signal with the receive signal, the system avoids the high power consumption associated with complex digital signal processing while achieving effective EMI suppression.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent changes the domain parameter from digital to analog for EMI mitigation. The cancellation signal is generated and processed in the analog domain before being summed with the receive signal, fundamentally changing the operational parameter domain to reduce power consumption while maintaining suppression effectiveness.

Inventive Principle:

Principle #35Parameter changes

3Measurement precision

If large EMI signal is added to receive signal, then EMI detection capability is improved, but signal distortion increases due to clipping and saturation

Engineering Contradiction:

ImproveEMI detection capabilityVSAvoidsignal quality

Core Design Contradiction:

Measurement precisionVSManufacturing precision

Solution Approach 1:

The patent applies preliminary anti-action by generating an analog cancellation signal that counteracts the EMI before it can cause clipping or saturation. The cancellation signal is summed with the receive signal in advance, preventing the harmful effects of large EMI signals rather than correcting them after distortion occurs.

Inventive Principle:

Principle #9Preliminary anti-action

Solution Approach 2:

The patent converts the harmful EMI signal into a beneficial cancellation signal. By deriving the cancellation signal from the receive signal and summing it appropriately, the system transforms the problematic EMI component into a useful element that actively reduces overall EMI impact on the link.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

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

Improved EMI suppression results in reduced transceiver complexity and cost, enabling better link operation and minimizing EMI distortion over a higher bandwidth, thus enhancing Ethernet system performance.

Implementation Method 1

The analog cancellation signal is summed with a receive signal, thereby mitigating electromagnetic interference in the receive signal

Methodology Applied

Scientific EffectDestructive interference: Interference

Data Source

PatentUS8792597B2Reducing electromagnetic interference in a receive signal with an analog correction signal

Publication Date: 2014.07.29 MARVELL ASIA PTE LTD

AI summary

Embodiments of methods and apparatuses for reducing electromagnetic interference in a receive signal are disclosed. One method includes receiving a receive signal. An analog cancellation signal is generated. The analog cancellation signal is summed with a receive signal, thereby mitigating electromagnetic interference in the receive signal. One apparatus includes a transceiver that includes a receive analog to digital converter (ADC) sampling a receive signal. Electromagnetic interference (EMI) processing circuitry generates an analog cancellation signal. The analog cancellation signal is summed with a receive signal, thereby mitigating electromagnetic interference in the receive signal.