A novel multilevel coherent optical system: 4-quadrature signaling

Author

Betti, Sivello ; Curti, Franco ; De Marchis, Giancarlo ; Iannone, Eugenio

Author_Institution

Fondazione Ugo Bordoni, Rome, Italy

Volume

9

Issue

4

fYear

1991

fDate

4/1/1991 12:00:00 AM

Firstpage

514

Lastpage

523

Abstract

A novel multilevel coherent optical system is proposed. It is based on the exploitation of the property that the electromagnetic field propagating in a single-mode optical fiber can be represented by a four-dimensional vector whose components are the phase and quadrature terms of the two polarization components of the electrical field. This allows a wider use of the resources of the electromagnetic field for information transmission in order to obtain a spectrally efficient modulation format with a limited end. The net performance gain with respect to multilevel amplitude and phase modulation (N-APK) and N-PSK increases with an increase in the number of levels N. For instance, for N=32 the gain is 1.6 and 7.7 dB with respect to N-APK and N-PSK systems. The effect of laser phase noise on the system performance is evaluated

Keywords

amplitude modulation; light coherence; light polarisation; optical links; optical modulation; phase modulation; vectors; 1.6 dB; 4-quadrature signaling; 4D EM field vectors; 7.7 dB; laser phase noise; multilevel amplitude modulation; multilevel coherent optical system; phase modulation; phase terms; polarization components; quadrature terms; single-mode optical fiber; Electromagnetic fields; Electromagnetic propagation; Electromagnetic wave polarization; Laser noise; Optical fiber polarization; Optical fibers; Optical propagation; Performance gain; Phase modulation; Phase noise;

fLanguage

English

Journal_Title

Lightwave Technology, Journal of

Publisher

ieee

ISSN

0733-8724

Type

jour

DOI

10.1109/50.76666

Filename

76666