Etude de technologies avancées pour l'optimisation des systèmes de transmission optique multiplexés en longueur d'onde au débit de 40 Gbit/s
Author | : Mathieu Lefrançois |
Publisher | : |
Total Pages | : 24 |
Release | : 2007 |
ISBN-10 | : OCLC:493506269 |
ISBN-13 | : |
Rating | : 4/5 (69 Downloads) |
Book excerpt: Wavelength-Division-Multiplexed fiber-optic transmission systems working at 40 Gbit/s channel bit rate will soon be essential to follow the expected increasing of capacity demand, that could no more be ensured by existing 10 Gbit/s systems. The study of advanced technologies that could allow the optimization of their performance is then essential. To ensure it, we first have studied modulation formats to be used with high capacity while ensuring optimal transmission. The phase-shaped binary transmission and the differential quaternary phase-shift keying meet these criterions. Furthermore we have studied the predominating nonlinear effects occurring at 40 Gbit/s, the so-called intrachannel nonlinear effects. The phase modulation also allows an high tolerance to these effects, which is enhanced by the use of a polarization alternation. We then have studied advanced systems especially developed for 40 Gbit/s channel bit rate. Through these systems studies, we first have shown that conventional submarine systems, originally developed for 10 Gbit/s bit rate, can be used at 40 Gbit/s bit rate with phase-modulated formats and dispersion-slope compensation. Then we have studied systems comprising an information coding device at the transmitter to allow the impact of intrachannel nonlinear effects to be lower with minimal changes in the original information sequence. Finally, we have shown that improved new-generation submarine systems, without in-line compensating fibers, but which comprise an optical phase-conjugation device, can potentially overlook existing submarine systems.