Open Access1 λ × 144 Tb/s free-space IM-DD transmission employing OAM multiplexing and PDM
Author(s) -
Yixiao Zhu,
Kaiheng Zou,
Zhennan Zheng,
Fan Zhang
Publication year - 2016
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.24.003967
Subject(s) - terabit , optics , multiplexing , physics , polarization division multiplexing , transmission (telecommunications) , wavelength division multiplexing , bit error rate , modulation (music) , forward error correction , free space optical communication , spectral efficiency , optical communication , computer science , channel (broadcasting) , wavelength , telecommunications , decoding methods , acoustics
We report the experimental demonstration of single wavelength terabit free-space intensity modulation direct detection (IM-DD) system employing both orbital angular momentum (OAM) multiplexing and polarization division multiplexing (PDM). In our experiment, 12 OAM modes with two orthogonal polarization states are used to generate 24 channels for transmission. Each channel carries 30 Gbaud Nyquist PAM-4 signal. Therefore an aggregate gross capacity record of 1.44 Tb/s (12 × 2 × 30 × 2 Gb/s) is acheived with a modulation efficiency of 48 bits/symbol. After 0.8m free-space transmission, the bit error rates (BERs) of all the channels are below the 20% hard-decision forward error correction (HD-FEC) threshold of 1.5 × 10(-2). After applying the decision directed recursive least square (DD-RLS) based filter and post filter, the BERs of two polarizations can be reduced from 5.3 × 10(-3) and 7.3 × 10(-3) to 2.2 × 10(-3) and 3.4 × 10(-3), respectively.