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Updated: Aug 27, 2025
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Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators
Published on: May 30, 2014
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Model-based end-to-end learning for a self-homodyne coherent system.
Optics Letters
|October 1, 2022
Summary
This study models noise in low-cost coherent systems using amplified spontaneous emission (ASE) sources. The optimized system improves information rates by 6.67% compared to 64-QAM, reducing the need for ASE bandwidth.
Area of Science:
- Optical communications
- Signal processing
Background:
- Investigates inherent intensity fluctuations in low-cost, low-complexity self-homodyne coherent systems.
- Utilizes an amplified spontaneous emission (ASE) source, common in cost-effective optical systems.
Purpose of the Study:
- Establish a noise distribution model for the described system.
- Design advanced mappers and demappers based on the noise model.
- Enhance system performance and data transmission rates.
Main Methods:
- Developed a noise distribution model for self-homodyne coherent systems.
- Experimentally validated the model with a 10 GBd 256-ary quadrature amplitude modulation (QAM) signal over 10 m duplex fiber.
- Designed and implemented optimized mappers and demappers.
Main Results:
- The noise model shows high consistency with experimental data.
- The optimized system alleviates the requirement for ASE bandwidth.
- Demonstrated a 6.67% increase in information rate compared to 64-QAM.
Conclusions:
- The developed noise model accurately represents system behavior.
- Advanced mappers and demappers improve system efficiency and performance.
- The optimized system offers a practical approach to increasing data rates in coherent optical communications.
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