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Published on: March 20, 2017
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Prototype system for real-time IM/DD MDM transmission based on multiple-ring-core FMF and degenerate-mode-selective
Optics Express
|December 28, 2019
Summary
This study introduces a novel digital signal processing-free scheme for mode division multiplexing (MDM) transmission. It enables real-time 4K video transmission over few-mode fiber without complex processing.
Area of Science:
- Optical Communications
- Fiber Optics
- Signal Processing
Background:
- Digital signal processing (DSP) presents a significant computational challenge for mode division multiplexing (MDM) systems.
- Existing IM/DD MDM systems often require complex DSP to manage modal crosstalk and demultiplex signals.
- There is a need for efficient and simplified MDM transmission schemes to reduce hardware complexity and cost.
Purpose of the Study:
- To propose and demonstrate a novel DSP-free intensity-modulation/direct-detection (IM/DD) MDM transmission scheme.
- To overcome the computational bottleneck associated with traditional MDM DSP.
- To enable real-time, high-capacity optical communication using simplified hardware.
Main Methods:
- Utilizing a few-mode fiber (FMF) with a multiple-ring-core structure to minimize modal crosstalk.
- Employing a degenerate-mode-selective fiber coupler for simultaneous demultiplexing of degenerate modes.
- Demonstrating the system using commercial single-mode (SM) 10 Gbps SFP+ modules and 4K video transceivers.
Main Results:
- Successful demonstration of the first DSP-free IM/DD MDM prototype system over 10 km of ultralow-modal-crosstalk FMF.
- Stable Q²-factor performance, indicating robustness against temperature and wavelength variations.
- Compatibility with commercial off-the-shelf components without hardware modification.
Conclusions:
- The proposed scheme offers a viable and smooth evolution path from conventional SM IM/DD systems.
- DSP-free IM/DD MDM transmission is achievable with advanced FMF design and mode-selective couplers.
- The architecture can be extended to support higher-order modes for increased capacity.
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