Alcatel

Alcatel N.v.

Alcatel Cit

Alcatel Fibres Optiques

Alcatel Cable France

Alcatel Fibers Optiques

Jean-Pierre Hamaide

Olivier Audouin

Pascale Nouchi

Pierre Sansonetti

Denis Penninckx

Jose Chesnoy

St&eacute;phanie Lanne

Emmanuel Desurvire

Dominique Lesterlin

Laurence Prigent

Elisabeth Brun

Sandrine Cussat-Blanc

Fr&eacute;d&eacute;ric Neddam

An optical fiber transmission system having Raman amplifier module for inputting a pumping signal into an optical fiber for stimulated Raman amplification of a first carrier signal. The Raman amplifier module includes a pump having two optical sources, wherein the first optical source emits a linear beam along a first polarization axis of polarization, and the second optical source emits another linear beam along a second polarization axis distinct from the first axis. The two beams are combined to for the pumping signal. The Raman amplifier module also includes a polarization tuning means arranged to superimpose in real time at least one of the polarization axes to a Polarization Dependant Loss axis.

Optical fiber transmission system

A device for compensating the polarization dispersion suffered by an optical signal when it is transmitted by an optical line includes a polarization controller. It generates a differential time delay between two orthogonal polarization modes and controls the polarization controller so that it converts the signal transmitted by the line into a compensated optical signal. If the quality of the compensated optical signal remains below a reference quality the device modifies the state of polarization of the optical signal. Applications include long distance optical transmission via standard fibers.

Device for compensating polarization dispersion in an optical transmission system

To increase the bit rate at which and the distance over which data can be transmitted by optical fiber, polarization dispersion is compensated by means of a polarization controller, a system for generating a differential group delay between two orthogonal modes of polarization and a control unit of the polarization controller. A chromatic dispersion compensator applies compensation which is adjusted dynamically to optimize the quality of the received optical signal. Applications include long-haul optical transmission on standard fibers.

System for compensating polarization dispersion in an optical transmission system

The invention relates to a method of stabilizing managed optical solitons propagating in a dispersion-managed optical fiber transmission line, said method being characterized in that the following are performed periodically along the transmission line for each managed optical soliton: a first step consisting in establishing coupling that is substantially linear between the energy and the spectrum width of the optical soliton; and a second step consisting in setting the spectrum width by filtering, and, by means of the substantially linear coupling, in setting the energy of the soliton resulting from the first step, the center frequency of the filtering being substantially equal to the center frequency of the optical soliton.

Method of stabilization optical solitons, and equipment for implementing the method

The invention enables wavelength division multiplexed (WDM) solitons conveyed by an optical fiber to be regenerated synchronously. The invention consists in using optical delay lines, in particular of the photorefractive filter type, prior to the regenerators so as to resynchronize a subset of the m soliton channels, and in placing the regenerator at a position where the n-m other soliton channels are naturally synchronized.

Method and device for on-line regeneration of a signal transmitted by wavelength division multiplexed solitons and optical telecommunication system comprising such a regenerating device

Dispersion-shifted monomode optical fibers have an effective mode surface area greater than 65 &mgr;m by optimization of the geometrical characteristics that characterize the fibers.

Dispersion-shifted monomode optical fiber

Dispersion-shifted monomode optical fibers have an effective mode surface area greater than 65 .mu.m.sup.2 by optimization of the geometrical characteristics that characterize the fibers.

Light pulses carrying data in binary form to be transmitted are injected into a transoceanic line fiber in which they pass through amplifiers imparting Gordon-Haus jitter to them. In accordance with the invention, a compensation fiber is disposed at the output of the line fiber so as to apply negative chromatic dispersion to the pulses so as to compensate their jitter in part before they are processed in a receiver. The invention applies to telecommunications.

System and a method for performing soliton transmission

An electrical power supply (20, 22) powers a semiconductor laser chip (2) under gain switching conditions so as to make the chip emit light pulses. The light pulses are compressed in a fiber (30) having negative dispersion, so that they constitute solitons. Their spectrum width is decreased by the fact that a gain segment powered by the power supply constitutes only a portion of the length of the resonant cavity of the chip. The invention applies to transmitting data over optical fibers.

Gain-switched semiconductor light pulse source, and a soliton

An optical communication link with correction of non-linear effects comprises an optical fiber transmission line subject to chromatic dispersion and non-linear effects and correction means for limiting the disadvantageous consequences of this dispersion and/or these non-linear effects. The correction means comprise at the output of the transmission line a dispersion compensator adapted to apply dispersion in the opposite direction to and of lower absolute value than the dispersion due to the transmission line.

Growing community of inventors

St Germain les Arpajon, France

Jean-Pierre Hamaide