6×56-Gb/s mode-division multiplexed transmission over 33-km few-mode fiber enabled by 6×6 MIMO equalization

Area of Science:

• Optical communications
• Photonics
• Fiber optics

Background:

• Mode-division multiplexing (MDM) increases fiber capacity by utilizing multiple spatial modes.
• Mode coupling in few-mode fibers (FMFs) causes crosstalk and intersymbol interference (ISI), limiting system performance.
• Effective compensation techniques are crucial for realizing the potential of MDM.

Purpose of the Study:

• To investigate the feasibility of mode-division multiplexing over a 33-km FMF link.
• To evaluate the performance of a 6x6 multiple-input multiple-output (MIMO) digital signal processing (DSP) approach for crosstalk and ISI mitigation.
• To demonstrate high-speed data transmission using a novel FMF supporting six spatial and polarization modes.

Main Methods:

• Transmission of uncorrelated 28-GBaud Quadrature Phase-Shift Keying (QPSK) signals over a 33-km FMF.
• Implementation of 6x6 MIMO digital signal processing to compensate for mode coupling effects.
• Characterization of crosstalk and ISI in the MDM system.

Main Results:

• The 6x6 MIMO processing effectively compensated for crosstalk and ISI caused by mode coupling.
• High-speed QPSK signals were successfully transmitted over the 33-km FMF link.
• The novel FMF supported six spatial and polarization modes, enabling increased data capacity.

Conclusions:

• MDM over FMF is a viable technology for future high-capacity optical networks.
• Advanced digital signal processing, such as 6x6 MIMO, is essential for overcoming FMF impairments.
• The developed system shows promise for next-generation optical communication systems.