Abstract: A Raman amplifier comprising a gain control unit adapted to control a pump power of an optical pump signal in response to at least one monitored optical feedback signal reflected back from a transmission line fiber connected to said pumped Raman amplifier.

Abstract: Methods and systems for post-transient gain control of optical amplifiers may include using a gain offset control module in an optical amplifier to generate a gain offset cancelling signal. The gain offset cancelling signal may be output to a gain control module in the optical amplifier to generate at least one of a pump signal and an attenuation control signal. In this manner, a gain offset may be cancelled for a plurality of wavelengths in an optical signal transmitted by an optical network.

Abstract: Methods and systems for post-transient gain control of optical amplifiers may include using a gain offset control module in an optical amplifier to generate a gain offset cancelling signal. The gain offset cancelling signal may be output to a gain control module in the optical amplifier to generate at least one of a pump signal and an attenuation control signal. In this manner, a gain offset may be cancelled for a plurality of wavelengths in an optical signal transmitted by an optical network.

Abstract: A method and apparatus for suppressing pump-mode optical beat interference noise in a Raman amplified fiber link of an optical network, wherein a wavelength of a laser beam generated by a first pump laser and a wavelength of a laser beam generated by a second pump laser of a pair of polarization multiplexed pump lasers are detuned with respect to each other to suppress the optical beat interference, OBI, noise in the Raman amplified fiber link of said optical network.

Abstract: The invention relates to a directionless and colorless reconfigurable optical add/drop multiplexer (ROADM) for a number of clients comprising: an add/drop interface for optical signals of at least one optical network, wherein each received optical signal is split by at least one optical splitter into optical signals which are applied to a downstream cross connector distributing the split optical signals to wavelength selectors of different clients, wherein each wavelength selector performs a wavelength selection of at least one wavelength from the distributed optical signals, wherein an optical signal having a selected wavelength (?) is applied to a client transponder of a client.

Abstract: A Raman amplifier comprising a gain control unit adapted to control a pump power of an optical pump signal in response to at least one monitored optical feedback signal reflected back from a transmission line fiber connected to said pumped Raman amplifier.

Abstract: It is described an optical amplification device for receiving an optical input signal and transmitting an amplified optical output signal on the basis of the optical input signal comprising an optical amplifier that comprises an input and an output. An optical gain control unit is connected to the output path of the optical amplifier and the optical gain control unit is connected to the input path of the optical amplifier. The optical gain control unit is configured to control the gain of the optical output signal. Additionally, an electrical gain control unit is connected to the output path of the optical amplifier. The electrical gain control unit is also connected to the input path of the optical amplifier. The electrical gain control unit is configured to control the gain of the optical output signal. By providing both an electrical gain control unit and an optical gain control unit, a control characteristic can be improved.

Abstract: A Raman amplifier comprising a gain control unit adapted to control a pump power of an optical pump signal in response to at least one monitored optical feedback signal reflected back from a transmission line fiber connected to said pumped Raman amplifier.

Abstract: A Raman amplifier comprising a gain control unit adapted to control a pump power of an optical pump signal in response to at least one monitored optical feedback signal reflected back from a transmission line fiber connected to said pumped Raman amplifier.

Abstract: It is described an optical amplification device for receiving an optical input signal and transmitting an amplified optical output signal on the basis of the optical input signal comprising an optical amplifier that comprises an input and an output. An optical gain control unit is connected to the output path of the optical amplifier and the optical gain control unit is connected to the input path of the optical amplifier. The optical gain control unit is configured to control the gain of the optical output signal. Additionally, an electrical gain control unit is connected to the output path of the optical amplifier. The electrical gain control unit is also connected to the input path of the optical amplifier. The electrical gain control unit is configured to control the gain of the optical output signal. By providing both an electrical gain control unit and an optical gain control unit, a control characteristic can be improved.

Abstract: The invention relates to a directionless and colorless reconfigurable optical add/drop multiplexer (ROADM) for a number of clients comprising: an add/drop interface for optical signals of at least one optical network, wherein each received optical signal is split by at least one optical splitter into optical signals which are applied to a downstream cross connector distributing the split optical signals to wavelength selectors of different clients, wherein each wavelength selector performs a wavelength selection of at least one wavelength from the distributed optical signals, wherein an optical signal having a selected wavelength (?) is applied to a client transponder of a client.

Abstract: An optical modulator for a high power laser transmitter includes a laser source coupled through a phase modulator to a signal modulator. A noise source provides a band limited noise signal to either the laser source or the phase modulator or both. Alternatively, an optical modulator for a high power laser transmitter includes a laser source providing a laser output optical signal and a phase modulator. First and second continuous wave signals at respective first and second frequencies are combined to modulate either the laser source or the phase modulator. The first frequency is different than the second frequency. The laser and phase modulation produces a broadened optical output signal such that the broadened optical output signal is characterized by beat frequencies harmonically related to the first and second frequencies. The modulation bandwidth includes no significant beat frequencies.

Abstract: An optical modulator for a high power laser transmitter includes a laser source coupled through a phase modulator to a signal modulator. A noise source provides a band limited noise signal to either the laser source or the phase modulator or both. Alternatively, an optical modulator for a high power laser transmitter includes a laser source providing a laser output optical signal and a phase modulator. First and second continuous wave signals at respective first and second frequencies are combined to modulate either the laser source or the phase modulator. The first frequency is different than the second frequency. The laser and phase modulation produces a broadened optical output signal such that the broadened optical output signal is characterized by beat frequencies harmonically related to the first and second frequencies. The modulation bandwidth includes no significant beat frequencies.