Reflectometry System Non-Linear Amplifier Correction

Solution Overview

Problem

Wired diagnostic systems using reflectometry face challenges in signal attenuation and non-linear amplifier effects, which degrade signal-to-noise ratio and make it difficult to detect and locate faults, especially soft faults, due to the non-linear behavior of amplifiers and frequency selectivity.

Innovation Solution

A reflectometry system with a digital signal generator, analog amplifier, and a pre-distortion device that calculates and applies a compensation function to the signal to correct the non-linear effect of the amplifier, using a mechanism that limits additional components and maintains system size, incorporating a decision-making device to estimate distortion and control connections for calibration and injection phases.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If an amplifier is used to amplify the signal before injection to limit attenuation effects, then signal propagation capability is improved, but non-linear behavior degrades signal-to-noise ratio and causes spectral spreading

Engineering Contradiction:

Improvesignal propagation capabilityVSAvoidsignal-to-noise ratio

Core Design Contradiction:

ReliabilityVSMeasurement precision

Solution Approach 1:

The system performs a calibration phase before actual fault detection to characterize the amplifier's non-linear behavior. By pre-measuring the amplifier's transfer function and storing calibration data, the system prepares compensation parameters in advance that will be applied during signal processing, thus eliminating the harmful non-linear effects while maintaining the amplification benefits

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system uses the reflected signal from the transmission line as feedback to characterize the amplifier's non-linear behavior. By analyzing the known reflected signal from a fault or termination, the system can determine the amplifier's actual transfer function and use this information to compensate for non-linear effects in subsequent measurements

Inventive Principle:

Principle #23Feedback

2Reliability

If an amplifier is used to amplify the signal before injection to limit attenuation effects, then signal propagation capability is improved, but spectral spreading occupies prohibited frequency bands

Engineering Contradiction:

Improvesignal propagation capabilityVSAvoidspectral spreading

Core Design Contradiction:

ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The system performs a calibration phase before actual fault detection to characterize the amplifier's non-linear behavior. By pre-measuring the amplifier's transfer function and storing calibration data, the system prepares compensation parameters in advance that will be applied during signal processing, thus eliminating the harmful non-linear effects while maintaining the amplification benefits

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system uses the reflected signal from the transmission line as feedback to characterize the amplifier's non-linear behavior. By analyzing the known reflected signal from a fault or termination, the system can determine the amplifier's actual transfer function and use this information to compensate for non-linear effects in subsequent measurements

Inventive Principle:

Principle #23Feedback

3Measurement precision

If a pre-distortion device with feedback loop is added to correct non-linear effects, then measurement precision is improved, but device complexity increases

Engineering Contradiction:

Improvefault detection accuracyVSAvoidsystem component count

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

Instead of adding complex physical pre-distortion hardware, the system creates a digital copy or model of the amplifier's non-linear behavior through calibration. This mathematical model is then used to compute compensation factors that are applied in the digital domain, avoiding the need for additional analog pre-distortion components while achieving the same correction effect

Inventive Principle:

Principle #26Copying

Solution Approach 2:

The system replaces the proposed mechanical/electrical pre-distortion feedback loop with a digital signal processing approach. By using digital computation to apply compensation based on calibration data, the system achieves non-linear correction without the complexity of additional analog components, feedback amplifiers, or real-time pre-distortion hardware

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Data Source

PatentEP3646045B1Reflectometry system for analysing faults in a transmission line

Publication Date: 2023.07.26 COMMISSARIAT A LENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES

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AI summary

The invention relates to a reflectometry system that comprises an amplifier for the signal to be injected into the cable being analysed, and which includes a mechanism for correcting the non-linear effect of the amplifier, without the space required by said system being increased significantly since the number of additional components to be incorporated remains limited compared to a system that does not have non-linearity correction.