Alain Bertaina

Experimental investigation of stimulated Raman scattering limitation on WDM transmission over various types of fiber infrastructures

We measure the impact of stimulated Raman scattering on the power distribution of a 32-channel multiplex after 100-km transmission over various fiber types. The Raman gain coefficient is then estimated in each configuration.

Dependence of self-phase modulation impairments on residual dispersion in 10-Gb/s-based terrestrial transmissions using standard fiber

We carry out, by computer simulation, an extensive investigation of the impact of residual dispersion on power margins induced by self-phase modulation in typical 5/spl times/100 km-long terrestrial transmission systems at 10 Gb/s, using standard single-mode fiber and modular dispersion compensation. We show that the most performing compensation technique is postcompensation, with positive residual dispersion, and that precompensation must be avoided in case of dual-stage amplification. We also propose a design rule to perform optimal dispersion compensation in multichannel transmissions.

Experimental investigation of dispersion management for an 8/spl times/10 Gbit/s WDM transmission over non-zero dispersion shifted fiber

We experimentally demonstrate that an 8/spl times/10 Gbit/s wavelength-division multiplexing (WDM) transmission with 200-GHz channel spacing over nonzero-dispersion-shifted fiber requires dispersion management when using field channel powers. This is then investigated and optimized.

320-Gb/s (32 x 10 Gb/s WDM) transmission over 500 km of conventional single-mode fiber with 125-km amplifier spacing

Thirty-two 10-Gb/s channels spaced by 100 GHz are transmitted over 500 km of dispersive fiber (D>+19 ps/nm/spl middot/km) with 125-km amplifier spacing. This is made possible by the use of 3 in-line dual-stage flat-gain erbium-doped fiber amplifiers (EDFAs) incorporating dispersion-compensating fiber. The transmission performance is significantly improved when a 9-km section of dispersion compensating fiber is added at the receiver end, for the longer-wavelength half of the multiplex.

Optimized NZDSF-based link for wide-band seamless terrestrial transmissions

We have designed and manufactured an optimized nonzero dispersion shifted fibre (NZDSF) based link for wide-band seamless terrestrial transmissions through minimization of higher-order dispersion (up to 4/sup th/-order dispersion). This link is composed of a new low-slope NZDSF with optimum dispersion of /spl sim/8 ps/nm-km and slope of /spl sim/0.03 ps/nm/sup 2/-km@1550 nm and a matched dispersion compensated fibre (DCF) in a module with low and flat attenuation over the S-, C- and L-bands. A maximum link-dispersion variation of /spl plusmn/0.18 ps/nm-km over 165 nm-bandwidth ranging from 1460 to 1625 nm was experimentally demonstrated. This is to our knowledge the lowest dispersion variation reported to date over such a wide bandwidth.

Advance in long-haul fibers

Dramatic increase in transmission systems capacity has recently been reported in long-haul terrestrial transmission systems. This paper will review advances in transmission and compensating fibers that opened the door to such transmission capability improvements.

Optical communication and fiber design

Optical fiber has evolved from a not-so-transparent glass tube to an extraordinarily efficient transmission medium. It is now acknowledged as a central element of modern telecommunication being part of the whole optimization process to further improve transmission system performance and cost. In this paper, we briefly introduce transmission system optimization problematics as well as key fiber characteristics. We then review the elements of fiber design for optimized optical communication networks, including metropolitan, long and ultra-long haul applications and show how fibers have evolved over the last ten years to keep pace with more and more demanding requirement of transmission system.RésuméD’un tube de verre peu transparent, la fibre optique a évolué vers un moyen de transmission d’une remarquable efficacité. La fibre est maintenant reconnue comme un élément central des réseaux de communications modernes. Son optimisation permet d’améliorer les performances et les coûts des systèmes de transmission. Dans cet article, nous rappelons les problèmes mis en jeu dans l’optimisation d’un système de transmission, ainsi que les caractéristiques essentielles des fibres optiques. Nous présentons ensuite les éléments clés de la conception des fibres qui ouvrent la voie à des réseaux de communications optimisés, incluant les applications pour le métropolitain, les longues et ultra-longues distances. Enfin, nous montrons comment les fibres ont évolué pour s’adapter aux contraintes toujours plus fortes imposées par les systèmes de transmission.

Line fibers for new transmission windows

The potential transmission bandwidth of optical fiber is very large (1300 nm-1700 nm). Apart from the classical C-band, optical transmissions can use the O, E, S, L and U bands. This paper reviews the enabling parameters required for the line fiber to open these new windows.

Investigation of the limitations of WDM typical terrestrial transmissions over NZDSF and SMF

WDM transmission limitations at 10Gbit/s over NZDSF are analyzed numerically on uncompensated and dispersion-managed links. The results are then compared to that obtained with a dispersion-managed transmission based on SMF.

High-throughput WDM transmission

We present the design of high-throughput WDM terrestrial transmission systems. Management of dispersion, nonlinearity, and amplification is reviewed and illustrated through high spectral efficiency transmission of channels at 10 and 40 Gbit/s. Dense-wavelength division multiplexing (DWDM) is a powerful technique to increase the capacity of advanced optical networks, to cope with the data traffic explosion. The full use of the optical fibre bandwidth, leading to cost-effective solutions, requires technologies and system design dealing with fibre attenuation, chromatic dispersion and nonlinearities.