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High-order QAM NANF transmission utilizing MIMO equalizer integrated with low-complexity decision-directed carrier
Optics Letters
|May 1, 2024
Summary
High-speed optical fiber communication was achieved using nested anti-resonant nodeless fiber (NANF) with polarization division multiplexing (PDM) and probabilistic shaping (PS). This advanced system successfully transmitted a 60-Gbaud PDM-PS-256QAM signal over 2 km, meeting forward error correction thresholds.
Area of Science:
- Optical Communications
- Fiber Optics Engineering
- Signal Processing
Background:
- Nested anti-resonant nodeless fiber (NANF) offers potential for high-capacity optical transmission.
- Polarization division multiplexing (PDM) and probabilistic shaping (PS) are advanced techniques for enhancing spectral efficiency.
- Existing equalization methods face challenges with crosstalk and phase disturbances in complex modulation formats.
Purpose of the Study:
- To experimentally demonstrate high-speed optical transmission using NANF.
- To integrate and validate a robust signal processing scheme for PDM-PS signals.
- To achieve transmission beyond the soft-decision forward error correction (SD-FEC) threshold.
Main Methods:
- Experimental realization of a high-speed transmission system.
- Utilizing polarization division multiplexing (PDM) and probabilistic shaping (PS) technologies.
- Implementing a low-complexity multiple-input multiple-output (MIMO) real-valued equalizer (RVE) integrated with decision-directed carrier phase estimation (DDCPE).
Main Results:
- Successful transmission of a 60-Gbaud PDM-PS-256QAM signal.
- Demonstrated robustness against IQ crosstalk and phase disturbance.
- Achieved signal transmission over a 2-km NANF link.
Conclusions:
- The proposed MIMO-RVE-DDCPE scheme effectively overcomes signal impairments in high-order modulation formats.
- High-speed transmission in NANF is feasible with advanced signal processing.
- The system meets the stringent requirements of soft-decision forward error correction (SD-FEC).
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