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Updated: Jul 4, 2025
09:43
Transmission of Multiple Signals through an Optical Fiber Using Wavefront Shaping
Published on: March 20, 2017
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OAM mode-division multiplexing IM/DD transmission at 4.32 Tbit/s with a low-complexity adaptive-network-based fuzzy
Optics Letters
|February 1, 2024
Summary
A novel low-complexity adaptive-network-based fuzzy inference system (LANFIS) equalizer effectively compensates for nonlinear impairments in high-speed orbital angular momentum (OAM) mode-division multiplexing (MDM) systems. This advanced equalizer significantly improves receiver sensitivity and reduces computational complexity for optical fiber communications.
Area of Science:
- Optical Communications
- Signal Processing
- Information Theory
Background:
- High-speed optical fiber communication systems, particularly those employing orbital angular momentum (OAM) mode-division multiplexing (MDM), face significant performance limitations due to stochastic nonlinear impairments.
- Intensity-modulation direct-detection (IM/DD) systems are widely used but susceptible to these distortions, necessitating advanced compensation techniques.
Purpose of the Study:
- To introduce and evaluate a low-complexity adaptive-network-based fuzzy inference system (LANFIS) nonlinear equalizer for WDM-OAM-MDM IM/DD systems.
- To demonstrate the LANFIS equalizer's ability to mitigate stochastic nonlinear impairments and improve transmission performance.
Main Methods:
- The proposed LANFIS equalizer adapts the probability distribution functions (PDFs) of distorted pulse amplitude modulation (PAM) symbols to match the channel's statistical characteristics.
- The equalizer was tested in a system with three OAM modes and 15 wavelength division multiplex (WDM) channels at 1550.12 nm.
Main Results:
- The LANFIS equalizer achieved superior performance compared to Volterra and Convolutional Neural Network (CNN) equalizers, showing improvements in receiver sensitivity of up to 2 dB.
- Significant complexity reductions were observed: 67% compared to Volterra, 74% compared to CNN, and 99.9% compared to Adaptive Neuro-Fuzzy Inference System (ANFIS).
Conclusions:
- The LANFIS equalizer effectively compensates for stochastic nonlinear impairments in high-speed WDM-OAM-MDM systems.
- Its combination of high performance and low computational complexity makes it a highly promising solution for future optical communication systems.
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