Abstract: An optical communication line of a communication system has a first processing station and an amplifying station. The line has a first optical connection having at least partially compensated accumulated dispersion and is placed between the first processing station and the amplifying station. A second optical connection having at least partially compensated accumulated dispersion is connected to the output of the amplifying station. Portions of optical fiber leaving the processing station and the amplifying station are associated to respective first order chromatic dispersions which are of opposite signs and have absolute values lower than or equal to 13 ps2/Km.

Abstract: An optical system having an optical fiber path suitable for propagating an optical signal at least in a first direction, and a plurality M of optical amplifiers disposed along the optical fiber path so as to divide the optical fiber path in N spans of optical fiber. The spans of optical fiber all have substantially a length Lamp and have at least one transmission optical fiber having an effective length Leff. An optical phase conjugation device is associated to one of the amplifiers of the plurality of amplifiers and is disposed in combination with a dispersion compensator. The compensator is disposed upstream from the amplifier associated to the optical phase conjugation device and is adapted for introducing an accumulated dispersion such as to substantially compensate the dispersion accumulated in a portion having a length (Lamp?Leff) of the span immediately upstream from the amplifier associated to the optical phase conjugation device.

Abstract: An optical communication line of a communication system has a first processing station and an amplifying station. The line has a first optical connection having at least partially compensated accumulated dispersion and is placed between the first processing station and the amplifying station. A second optical connection having at least partially compensated accumulated dispersion is connected to the output of the amplifying station. Portions of optical fiber leaving the processing station and the amplifying station are associated to respective first order chromatic dispersions which are of opposite signs and have absolute values lower than or equal to 13 ps2/Km.

Abstract: An optical communication line for transmitting an optical signal having a predetermined wavelength has a plurality of spans and at least one PMD compensation device adapted to process the optical signal so as to obtain in output a polarized optical signal having associated a maximum power fraction of the optical signal. The PMD compensation device is inserted between two spans of the line.

Abstract: A PMD mitigation apparatus for mitigating the effects of PMD of a plurality of input optical signals, has a processing unit having a first input for the plurality of input optical signals, a second input and an output; a feedback control unit having an input coupled to the output of the processing unit and an output coupled to the second input of the processing unit. Under the control of a control signal, the processing unit is adapted to act on the polarization of the plurality of input optical signals separately so as to obtain at its output an aggregate having a corresponding plurality of polarized optical signals having associated a maximum fraction of power of the plurality of input optical signals. The feedback control unit is adapted to receive at its input a power portion of the aggregate of the plurality of polarized optical signals, to process the optical power portion so as to generate the control signal to the second input of the processing unit.

Abstract: An optical system has an optical fiber path suitable for propagating an optical signal at least in a first direction, and a plurality of optical line amplifiers disposed along the optical fiber path so as to divide the optical fiber path in spans of optical fiber. The spans of optical fiber have at least one transmission optical fiber having an effective length Leff. An optical phase conjugation device is associated to one of the amplifiers of the plurality of amplifiers, and is disposed in combination with an optical fiber length having the same sign of dispersion of the transmission optical fiber and a higher dispersion coefficient at a wavelength of the optical signal. The additional accumulated dispersion introduced by the optical fiber length is nearly equal to the dispersion accumulated in an effective length Leff of transmission fiber. A further optical amplifier is associated to the optical fiber length.

Abstract: An optical system having an optical fiber path suitable for propagating an optical signal at least in a first direction, and a plurality M of optical amplifiers disposed along the optical fiber path so as to divide the optical fiber path in N spans of optical fiber. The spans of optical fiber all have substantially a length Lamp and have at least one transmission optical fiber having an effective length Leff. An optical phase conjugation device is associated to one of the amplifiers of the plurality of amplifiers and is disposed in combination with a dispersion compensator. The compensator is disposed upstream from the amplifier associated to the optical phase conjugation device and is adapted for introducing an accumulated dispersion such as to substantially compensate the dispersion accumulated in a portion having a length (Lamp?Leff) of the span immediately upstream from the amplifier associated to the optical phase conjugation device.

Abstract: An optical system having an optical fiber path suitable for propagating an optical signal at least in a first direction, a plurality of optical gain modules disposed along the optical fiber path so as to divide the optical fiber path in N spans of optical fiber. Each span of optical fiber has at least one transmission optical fiber connected downstream from the optical gain modules. An optical phase conjugation device is disposed at a predetermined distance downstream from one of the optical gain modules.