Open AccessSpectrally efficient pilot tone-based compensation of inter-channel cross-phase modulation noise in a WDM coherent transmission using injection locking
Author(s) -
Takashi Kikuchi,
Kôzô Satô,
Masato Yoshida,
Toshihiko Hirooka,
Keisuke Kasai,
Masataka Nakazawa
Publication year - 2021
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.414381
Subject(s) - optics , phase noise , wavelength division multiplexing , cross phase modulation , modulation (music) , transmission (telecommunications) , channel spacing , quadrature amplitude modulation , spectral efficiency , wideband , qam , bit error rate , phase modulation , physics , compensation (psychology) , channel (broadcasting) , computer science , telecommunications , acoustics , wavelength , psychology , psychoanalysis
We propose the precise and wideband compensation of the nonlinear phase noise caused by cross-phase modulation (XPM) among WDM channels using a pilot tone (PT) and injection locking for short-reach, higher-order QAM transmission. A high spectral efficiency is maintained by sharing a single PT among multiple channels. We describe a 60 ch, 3 Gbaud PDM-256 QAM transmission over 160 km, where the bit error rate was improved from 6 × 10 -3 to 2 × 10 -3 by employing the proposed XPM compensation technique, with a spectral efficiency of 10.3 bit/s/Hz. We also analyze the influence of the group delay caused by fiber chromatic dispersion that determines the compensation range achievable with a single PT. We obtained good agreement with the experimental results.