Abstract: A Raman amplifier with a number of pump lasers whose pump signals are regulated. In order to improve the frequency stability, the pump lasers are followed by optical filters. Polarization mixers produce a constant gain for different polarizations of a WDM signal. Matching to different transmission conditions and to a different number of transmission bands can be carried out via a controller.

Abstract: A pump source for broadband amplification of a wavelength-division multiplexed signal transmitted via an optical fiber having a number of low-power pump lasers, whose input signal power levels are increased in a conversion fiber. One or more high-power lasers such as Raman cascade lasers on the one hand, and one or more monomode laser diodes with a low output power, on the other hand, are used as the pump lasers. Pump signals from the monomode laser diodes are subjected to Raman amplification in the conversion fiber before providing broadband amplification of the WDM signal in the transmission fiber by stimulated Raman scatter. The powers required for the amplified pump signals at the output of the conversion fiber are achieved by respective pump power increases in the pump signals of the monomode laser diodes, and by using monomode laser diodes with different output powers, as well as via a corresponding arrangement of the input coupling of the output signals of the pump lasers into the conversion fiber.

Abstract: A system and method for measuring and compensating for the polarization mode dispersion of first and higher orders for a transmitted optical signal are described wherein the propagation time difference, caused from polarization mode dispersion, between orthogonally polarized signals of the transmitted optical signal can be determined very precisely, and can be compensated for, even above a delay of a bit duration of the data signal.

Abstract: An optical amplifier and optical amplifier arrangement with reduced cross phase modulation wherein in an active fiber of the optical amplifier, the fiber being doped with ions of elements from the group of rare earths, in order to reduce the cross phase modulation of the optical amplifier, at least one active fiber section is allocated a dispersion coefficient having a high magnitude, in which the optical transmission signal to be amplified assumes a high signal level.

Abstract: A pumping source is provided for the Raman amplification of an optical wavelength division multiplex signal, wherein the pumping source has a number of pumping lasers with, in each case, different pumping wavelengths. Modules for the angle and/or amplitude modulation of pumping signals of the pumping lasers are connected to the pumping lasers, such that by appropriate adaptation of the modulation of the pumping signals mixing products from four-wave mixing between the pumping signals are suppressed.

Abstract: An optical transmission system for wavelength-division multiplex signals, having cascaded Raman amplifiers, has a number of pump sources for each Raman amplifier, each having different pump wavelengths sets from one pump source to another pump source. This results in a flat gain spectrum for all the channels in a WDM transmission signal.

Abstract: The invention relates to the transmission of optical signals (C-Bein,L-Bein) in conventional transmission bands, especially C-bands and L-bands, and of additional optical signals (S+-Bein) in the S+-band by means of an optical fiber (OF). At least one optical pump signal (ps1, ps2) is coupled into the optical fiber (OF) for amplifying the additional optical signals (S+-Bein) by means of the Raman effect, whereby said additional signals are transmitted in the S+-band. The wavelength of the at least one optical pump signal (ps1, ps2) is situated in the wave range of 1,320 nm to 1,370 nm.

Abstract: A method for producing non-equidistant pump waves for Raman amplification of a signal which is passed via an optical waveguide, as well as a pump wave producing apparatus for producing pump waves for Raman amplification of a signal which is passed via an optical waveguide, which apparatus has at least one pump source and is set up such that it can produce pump waves at a first, a second, a third and a fourth mutually equidistant pump wavelength, having a control device which is set up such that it causes, in each case, the production of a pump wave u, v, w at the first, second and fourth pump wavelengths, with the control device being set up such that no pump wave is produced at the third pump wavelength, so that a non-equidistant pump channel pattern is achieved overall.

Abstract: In an optical transmission system, optical wavelength division multiplexed signals are transmitted via an optical fiber, wherein the signal-to-noise ratio of the optical transmission system is improved by setting the power levels of the optical WDM signals at the start of the optical fiber such that the optical WDM signals in the optical fiber have at least approximately the same minimum power levels, thus leading to the signal-to-noise ratios of the output of the optical transmission path being approximately the same.

Abstract: A pump source for broadband amplification of a wavelength-division multiplexed signal transmitted via an optical fiber having a number of low-power pump lasers, whose input signal power levels are increased in a conversion fiber. One or more high-power lasers such as Raman cascade lasers on the one hand, and one or more monomode laser diodes with a low output power, on the other hand, are used as the pump lasers. Pump signals from the monomode laser diodes are subjected to Raman amplification in the conversion fiber before providing broadband amplification of the WDM signal in the transmission fiber by stimulated Raman scatter. The powers required for the amplified pump signals at the output of the conversion fiber are achieved by respective pump power increases in the pump signals of the monomode laser diodes, and by using monomode laser diodes with different output powers, as well as via a corresponding arrangement of the input coupling of the output signals of the pump lasers into the conversion fiber.

Abstract: Regulated optical amplifiers for wavelength-division multiplex signal transmission that include a first control device for regulating the gain and a second, dominating control device having a significantly slower control behavior for regulating the output power level in conformity with a supplied rated power value. Both rapid level changes as well as slow changes in attenuation of the transmission path can be leveled with a transmission path utilizing these amplifiers.

Abstract: For amplification of optical signals which are transmitted via an optical transmission medium, at least one optical pump signal is injected in the transmission direction into the optical transmission medium in order to produce the Raman effect. In this case, the spectral power density, which relates to the optical signal wavelength band, of the at least one optical pump signal is reduced via at least one filter unit such that the remaining spectral power density is below the shot noise limit.

Abstract: An optical amplifier arrangement having at least one optical amplifier stage (V1, V2) and a variably settable attenuator (VDL), whose attenuation spectrum (DV2, DV3, DV5, DV6) assumes an attenuation profile (DV2, DV3, DV5, DV6) that increases or decreases proportionally to wavelength. To reduce tilt of the channel level spectrum of an optical transmission signal, the profile of the attenuation spectrum (DV2, DV3, DV5, DV6) is variably settable. An advantageous structure of the variably settable attenuator according to the invention is furthermore specified.

Abstract: An optical transmission system for wavelength-division multiplex signals, having cascaded Raman amplifiers, has a number of pump sources for each Raman amplifier, each having different pump wavelengths sets from one pump source to another pump source. This results in a flat gain spectrum for all the channels in a WDM transmission signal.

Abstract: A Raman amplifier with a number of pump lasers whose pump signals are regulated. In order to improve the frequency stability, the pump lasers are followed by optical filters. Polarization mixers produce a constant gain for different polarizations of a WDM signal. Matching to different transmission conditions and to a different number of transmission bands can be carried out via a controller.

Abstract: A method for equalizing channel quality differences in a WDM system having N transmitters, N receivers and N channels wherein the following steps are performed: separately measuring in each case a bit error rate of each individual one of the N channels in each one of the N receivers, these being measured in each case at different decider thresholds, deviating from the optimum value, in N first decision circuits; determining the bit error rate at the optimum operating point by extrapolating the measured bit error rates for each individual one of the N channels; determining a Q value for each one of the N channels from the respective associated extrapolated bit error rates; calibrating the N transmitters via a control device by raising the levels of the channels having a high bit error rate and lowering the levels of the channels having a low bit error rate at the ratio of the respective Q value of the channel, the aggregate level of all N channels in the N transmitters being kept constant; and repeating the st

Abstract: A method for stabilization of a transparent photonic network having at least one WDM path which has a specific number of channels on which signals can be transmitted, and a method for reconfiguration of a transparent photonic network from a first WDM path to a second WDM path between two points which have a number of channels on which signals can be transmitted.

Abstract: An optical amplifier and optical amplifier arrangement with reduced cross phase modulation wherein in an active fiber of the optical amplifier, the fiber being doped with ions of elements from the group of rare earths, in order to reduce the cross phase modulation of the optical amplifier, at least one active fiber section is allocated a dispersion coefficient having a high magnitude, in which the optical transmission signal to be amplified assumes a high signal level.

Abstract: A cascadable optical amplifier arrangement having a modular base amplifier arrangement (BVA) that is constructed in single-mode technology and has at least one amplifier stage (VS1 to VS4). At least one high-power amplifier stage (HVS1) that has its own active fiber (AF) and at least one pump signal source (PSQ1, PSQ2) is connected to the at least one amplifier stage (VS4) of said base amplifier arrangement (BVA). In this way, a stepwise increase of the output power of an already existing base amplifier arrangement (BVA) can be achieved.

Abstract: The regulated optical amplifiers (V) for wavelength-division multiplex signal transmission respectively comprise a first control device (OE1, OE2, R1) for regulating the gain and a second, dominating control device (OE2, R2, R1) having a significantly slower control behavior for regulating the output level (POUT) in conformity with a supplied rated value (POUT). Both rapid level changes as well as slow changes in attenuation of the transmission path can be leveled given a transmission path equipped with these amplifiers.