Open AccessWeakly coupled 10-mode-division multiplexed transmission over 48-km few-mode fibers with real-time coherent MIMO receivers
Author(s) -
Shohei Beppu,
Koji Igarashi,
Masahiro Kikuta,
Daiki Soma,
T. Nagai,
Yasuo Saito,
Hidenori Takahashi,
Takehiro Tsuritani,
Ramon Casellas
Publication year - 2020
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.395415
Subject(s) - multiplexing , mimo , polarization division multiplexing , optics , physics , spatial multiplexing , transmission (telecommunications) , polarization (electrochemistry) , electronic engineering , wavelength division multiplexing , computer science , wavelength , beamforming , telecommunications , engineering , chemistry
For weakly coupled mode-division multiplexed (MDM) transmission systems, we design and implement optical coherent receiver prototypes with real-time multiple-input multiple-output (MIMO) digital signal processing to equalize two degenerate linearly polarized modes with dual polarization. Using field programmable gate array circuits, we implement real-value 8 × 2 MIMO adaptive equalization with externally separated phase compensators based on the least mean square algorithm, which enables not only training equalization but also fast carrier-phase tracking. With the optical coherent MIMO receiver prototype, we demonstrate real-time weakly coupled 10 × MDM wavelength-division multiplexed dual-polarization quadrature phase shift keying transmission over 48-km few-mode fibers. This report shows a record number of multiplexed spatial modes, namely, 10 modes with dual polarization, in real-time MDM transmission experiments.