Related Experiment Video
Updated: May 20, 2026
09:43
Transmission of Multiple Signals through an Optical Fiber Using Wavefront Shaping
Published on: March 20, 2017
High-order statistical equalizer for nonlinearity compensation in dispersion-managed coherent optical communications
Toshiaki Koike-Akino1, Chunjie Duan, Kieran Parsons
1MERL, 201 Broadway, Cambridge, Massachusetts 02139, USA. koike@merl.com
Optics Express
|July 10, 2012
Summary
A new equalizer tackles fiber nonlinearity in ultra-high-speed optical communications. This trained high-order statistics equalizer significantly boosts performance for long-haul data transmission.
Area of Science:
- Optical Communications
- Signal Processing
Background:
- Fiber nonlinearity is a key limitation for ultra-high-speed optical communication systems.
- Data-pattern dependent nonlinear impairments degrade signal quality.
Purpose of the Study:
- To propose and evaluate a novel fractionally-spaced equalizer.
- To mitigate nonlinear impairments in fiber-optic communications using trained high-order statistics.
Main Methods:
- A 3-tap fractionally-spaced equalizer was designed using trained high-order statistics.
- Computer simulations were performed for long-haul transmission scenarios.
- The equalizer's performance was evaluated in conjunction with digital backpropagation (DBP).
Main Results:
- The proposed equalizer improved the Q-factor by over 2 dB for 40 Gbps transmission over 5,230 km.
- Combining the equalizer with DBP provided an additional 1-2 dB improvement.
- Performance was assessed for future high-speed transmissions (100 Gbps and beyond).
Conclusions:
- The developed equalizer effectively combats data-pattern dependent nonlinear impairments.
- Joint optimization with DBP enhances performance through channel shortening.
- The approach shows promise for future ultra-high-speed optical communication systems.
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