Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Time-Domain Interpretation of PD Control

Time-Domain Interpretation of PD Control

Proportional-Derivative (PD) control is a widely used control method in various engineering systems to enhance stability and performance. In a system with only proportional control, common issues include high maximum overshoot and oscillation, observed in both the error signal and its rate of change. This behavior can be divided into three distinct phases: initial overshoot, subsequent undershoot, and gradual stabilization.
Consider the example of control of motor torque. Initially, a positive...

Power Factor Correction

Power Factor Correction

The power transmission to a factory involves the transfer of apparent power, a combination of active and reactive power. The power factor measures how effectively electrical power is converted into useful work output. The ratio of the real power (KW) that does the work to the apparent power (KVA) supplied to the circuit.

Linear Approximation in Frequency Domain

Linear Approximation in Frequency Domain

Linear systems are characterized by two main properties: superposition and homogeneity. Superposition allows the response to multiple inputs to be the sum of the responses to each individual input. Homogeneity ensures that scaling an input by a scalar results in the response being scaled by the same scalar.
In contrast, nonlinear systems do not inherently possess these properties. However, for small deviations around an operating point, a nonlinear system can often be approximated as linear.

Linear Approximation in Time Domain

Linear Approximation in Time Domain

Nonlinear systems often require sophisticated approaches for accurate modeling and analysis, with state-space representation being particularly effective. This method is especially useful for systems where variables and parameters vary with time or operating conditions, such as in a simple pendulum or a translational mechanical system with nonlinear springs.
For a simple pendulum with a mass evenly distributed along its length and the center of mass located at half the pendulum's length, the...

Time and frequency -Domain Interpretation of PI Control

Time and frequency -Domain Interpretation of PI Control

Proportional-Integral (PI) controllers are essential in many control systems to improve stability and performance. They are commonly used in everyday devices like thermostats to enhance system damping and reduce steady-state error. When the zero in the controller's transfer function is optimally placed, the system benefits significantly in terms of stability and accuracy.
Acting as a low-pass filter, the PI controller slows the system's response and extends settling times. This requires careful...

Pilot and Numeric Relaying

Pilot and Numeric Relaying

Pilot relaying is a type of differential protection used in power systems. It compares electrical quantities at the terminals of equipment via a communication channel instead of direct relay interconnection. This method is essential for transmission lines where the terminals are far apart, typically up to 80 km for lines with 69 to 115 kV ratings. Four types of communication channels are used for pilot relaying:

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Microcomb-enabled parallel self- calibration optical convolution streaming processor.

Light, science & applications·2026

Same author

A Model for Assessing the Electromagnetic Safety of an Inductively Coupled, Modular Brain-Machine Interface.

IEEE transactions on neural systems and rehabilitation engineering : a publication of the IEEE Engineering in Medicine and Biology Society·2022

Same author

Single-photodiode per polarization receiver with signal-signal beat interference suppression through heterodyne detection.

Optics express·2018

Same author

Photonic integrated circuit implementation of a sub-GHz-selectivity frequency comb filter for optical clock multiplication.

Optics express·2017

Same author

Hardware-efficient signal generation of layered/enhanced ACO-OFDM for short-haul fiber-optic links.

Optics express·2017

Same author

Cyclic spectra for wavelength-routed optical networks.

Optics letters·2017

Search research articles

Related Experiment Video

Updated: May 25, 2026

Gain-compensation Methodology for a Sinusoidal Scan of a Galvanometer Mirror in Proportional-Integral-Differential Control Using Pre-emphasis Techniques

Gain-compensation Methodology for a Sinusoidal Scan of a Galvanometer Mirror in Proportional-Integral-Differential Control Using Pre-emphasis Techniques

Published on: April 4, 2017

Pilot-based XPM nonlinearity compensator for CO-OFDM systems.

Liang B Y Du¹, Arthur J Lowery

¹Department of Electrical & Computer Systems Engineering, Monash University, Clayton, VIC 3800, Australia.

|January 26, 2012

Summary

Pilot-based compensation effectively reduces nonlinear impairments like cross-phase modulation (XPM) in coherent optical orthogonal frequency-division multiplexing (CO-OFDM) systems. This method enhances the nonlinear limit by 6 dB, with reduced pilot overhead for wider bandwidth signals.

More Related Videos

Operation of the Collaborative Composite Manufacturing (CCM) System

Operation of the Collaborative Composite Manufacturing (CCM) System

Published on: October 1, 2019

Generation and Coherent Control of Pulsed Quantum Frequency Combs

Generation and Coherent Control of Pulsed Quantum Frequency Combs

Published on: June 8, 2018

Related Experiment Videos

Last Updated: May 25, 2026

Gain-compensation Methodology for a Sinusoidal Scan of a Galvanometer Mirror in Proportional-Integral-Differential Control Using Pre-emphasis Techniques

Gain-compensation Methodology for a Sinusoidal Scan of a Galvanometer Mirror in Proportional-Integral-Differential Control Using Pre-emphasis Techniques

Published on: April 4, 2017

Operation of the Collaborative Composite Manufacturing (CCM) System

Operation of the Collaborative Composite Manufacturing (CCM) System

Published on: October 1, 2019

Generation and Coherent Control of Pulsed Quantum Frequency Combs

Generation and Coherent Control of Pulsed Quantum Frequency Combs

Published on: June 8, 2018

Area of Science:

Optical communications
Nonlinear optics
Signal processing

Background:

Coherent optical orthogonal frequency-division multiplexing (CO-OFDM) systems are susceptible to nonlinear impairments.
Cross-phase modulation (XPM) significantly degrades system performance.
Effective compensation strategies are crucial for advancing optical communication systems.

Purpose of the Study:

To experimentally verify the effectiveness of pilot-based nonlinearity compensation for mitigating XPM in CO-OFDM systems.
To quantify the improvement in the nonlinear limit achieved by the proposed compensation method.
To investigate the impact of signal bandwidth on pilot overhead requirements.

Main Methods:

Experimental verification of pilot-based XPM compensation in a 400-km optical link with periodic dispersion compensation.
Implementation of a single-step single-carrier-modulated optical orthogonal frequency-division multiplexing (SCM-OFDM) system with pilot tones.
Numerical simulations to analyze the guard-band requirements and optimal pilot power ratio for varying signal bandwidths.

Main Results:

A 6-dB increase in the nonlinear limit was achieved using pilot-based XPM compensation after single-step SPM compensation.
The required guard-band bandwidth around the pilot is nearly independent of the data-carrying sideband bandwidth.
The optimal pilot-to-signal power ratio decreases for higher bandwidth OFDM signals, reducing overhead.

Conclusions:

Pilot-based nonlinearity compensation is an effective technique for mitigating XPM in CO-OFDM systems, provided SPM is compensated first.
The proposed method offers a practical approach to enhance the nonlinear performance of optical communication systems.
The reduced pilot overhead for wider bandwidth signals makes this compensation strategy more efficient for future high-capacity systems.