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Transmission of Multiple Signals through an Optical Fiber Using Wavefront Shaping
Published on: March 20, 2017
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Improvement for a full-spectrum modulated nonlinear frequency division multiplexing transmission system.
Optics Express
|October 15, 2022
Summary
This study enhances nonlinear frequency division multiplexing (NFDM) for optical communication by optimizing full-spectrum (FS) modulation. This approach achieves higher data rates and improves transmission performance, overcoming Kerr nonlinearity limits.
Area of Science:
- Optical communication systems
- Nonlinear optics
- Signal processing
Background:
- Kerr nonlinearity limits conventional coherent optical communication.
- Nonlinear frequency division multiplexing (NFDM) offers a potential solution.
- Full-spectrum (FS) modulation aims to maximize spectral efficiency.
Purpose of the Study:
- To optimize the data rate of discrete spectrum (DS) in FS-NFDM systems.
- To improve the transmission performance of FS-NFDM systems.
- To achieve data rates exceeding current benchmarks.
Main Methods:
- Optimizing eigenvalue distribution in the discrete spectrum (DS) of FS-NFDM.
- Introducing probabilistic shaping (PS) into the FS system.
- Employing linear minimum mean square (LMMSE) estimators for signal recovery.
Main Results:
- Achieved 112 Gbps transmission over 1120 km with BER below HD-FEC threshold.
- Utilized 128 subcarriers (PS-64QAM) in continuous spectrum (CS) and 13 eigenvalues (64QAM) in DS.
- Demonstrated a 12% higher achievable data rate compared to pure CS modulation.
- Implemented the largest number of multiplexed eigenvalues in an FS-NFDM system to date.
Conclusions:
- The proposed FS-NFDM system with optimized DS and PS significantly enhances optical communication performance.
- This approach effectively overcomes limitations imposed by Kerr nonlinearity.
- The study provides a viable method for improving FS-NFDM system performance and data rates.
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