Open AccessDual-polarization OFDM-OQAM for communications over optical fibers with coherent detection
Author(s) -
François Horlin,
Jessica Fickers,
Philippe Emplit,
André Bourdoux,
Jérôme Louveaux
Publication year - 2013
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.21.006409
Subject(s) - computer science , orthogonal frequency division multiplexing , spectral efficiency , multiplexing , electronic engineering , wavelength division multiplexing , polarization division multiplexing , bit error rate , synchronization (alternating current) , optical communication , channel (broadcasting) , optics , quadrature amplitude modulation , minimum mean square error , telecommunications , physics , wavelength , mathematics , engineering , statistics , estimator
In order to improve the spectral efficiency of coherent optical communication systems, it has recently been proposed to make use of the orthogonal frequency-division multiplexing offset quadrature amplitude modulation (OFDM-OQAM). Multiple optical channels spaced in the frequency domain by the symbol rate can be transmitted orthogonally, even if each channel overlaps significantly in frequency with its two adjacent channels. The solutions proposed until now in the literature unfortunately only address a single polarization communication, and therefore do not benefit from the capacity gain reached when two polarizations are used to transmit independent information signals. The aim of the present paper is to propose a receiver architecture that can decouple the two polarizations. We build an equalizer per channel at twice the symbol rate and optimize it based on the minimum mean square error (MMSE) criterion. We demonstrate the efficiency of the resulting system compared to the Nyquist wavelength-division multiplexing (N-WDM) system both in terms of performance and complexity. We also assess the system sensitivity to transmit synchronization errors and show that system can even work under significant synchronization errors.