Abstract: Techniques are presented herein to setup a wavelength on a path from a source node to a destination node. Cross-talk margin information already computed for one or more installed wavelengths is obtained between the source node and destination node. A total margin as a function of the cross-talk margin information is computed. A determination is then made as to whether to perform non-linear impairment validation of the wavelength based on the total margin. These techniques may be generalized to account for coherent and non-coherent portions of a network.

Abstract: Techniques are presented herein to setup a wavelength on a path from a source node to a destination node. Cross-talk margin information already computed for one or more installed wavelengths is obtained between the source node and destination node. A total margin as a function of the cross-talk margin information is computed. A determination is then made as to whether to perform non-linear impairment validation of the wavelength based on the total margin. These techniques may be generalized to account for coherent and non-coherent portions of a network.

Abstract: The present invention proposes a method and a device to add and drop optical channels in an optical transmission system (1) in which a multi-channel optical signal is transmitted into an optical fiber line (300).

Abstract: An optical transmission system has been designed to optimize the use of the spectral emission range of rare-earth-doped fiber amplifiers. The system includes a wide band of channels in the spectral emission range of erbium-doped fiber amplifiers, which is split into two sub-bands, a low sub-band corresponding to the low end of the range and a high sub-band corresponding to the high end of the range. The two sub-bands are separately amplified and optimized, and then recombined without significant competition between the two sub-bands. In addition, an equalizing filter, such as a specialized Bragg filter or interferential filter, is applied to the low sub-band instead of the entire band of channels, thus greatly reducing any equalization need or unequalization effects.

Abstract: An optical fiber amplifier and filtering apparatus and method for a bidirectional wavelength-division-multiplexing (WDM) system having odd and even interleaved channels is disclosed. The apparatus uses optical circulators, in-fiber Bragg gratings, and erbium-doped fiber amplifiers to amplify channels traveling in opposite directions in a WDM system and to filter unwanted ASE and back reflection noise between the channels. Interface circulators positioned at opposite ends of the apparatus respectively receive odd and even channels traveling in opposite directions in the WDM system and pass the channels through an erbium-doped fiber amplifier. Other circulators direct the amplified channels to two series of Bragg gratings that respectively reflect only the odd channels and pass only the even channels or vice versa, thereby filtering ASE and other noise located between the channels. An additional amplifier may boost the channels before they exit the apparatus via the interface circulators.