Abstract: A method for transmitting data, wherein along a transmission path: (i) a modulated carrier signal is generated based on the data to be transmitted, the carrier signal having a carrier frequency within a given transmission channel, which is comprised of a number of frequencies, and (ii) the modulated carrier signal is amplified to a transmission signal, wherein along a compensation path: (i) the modulated carrier signal is filtered, whereby the frequency components within the transmission channel are removed, and at least one of a phase, an amplitude, and/or a delay of the filtered signal is modified thereby generating a compensation signal, and wherein the compensation signal is subtracted from the transmission signal thereby generating a compensated transmission signal, and wherein the compensated transmission signal is transmitted. Also a respective data transmission device is disclosed.

Abstract: A method for transmitting data, wherein along a transmission path: (i) a modulated carrier signal is generated based on the data to be transmitted, the carrier signal having a carrier frequency within a given transmission channel, which is comprised of a number of frequencies, and (ii) the modulated carrier signal is amplified to a transmission signal, wherein along a compensation path: (i) the modulated carrier signal is filtered, whereby the frequency components within the transmission channel are removed, and at least one of a phase, an amplitude, and/or a delay of the filtered signal is modified thereby generating a compensation signal, and wherein the compensation signal is subtracted from the transmission signal thereby generating a compensated transmission signal, and wherein the compensated transmission signal is transmitted. Also a respective data transmission device is disclosed.

Abstract: The invention describes a method and an arrangement for transmitting an optical transmission signal with reduced polarization-dependent loss. A first transmission signal component and a second orthogonal transmission signal component of the optical transmission signal are transmitted with a time difference between said transmission signal components.

Abstract: The present invention provides an apparatus, in particular an optical network unit, which comprises a first part operably coupled to an arm of an optical fiber network, the first part comprises an optical module including an optical-electric interface and/or an electric-optical interface locked on a preset wavelength band, and an interface module, and at least one second part operably coupled to a network entity of a communication network, each comprising a control unit, a signal processing unit and an interface module. One of the control units of the at least one second part is set by a optical line terminal of the optical fiber network as a master control unit configured to tune and control the optical module of the first part. The first part and the at least one second part are wireless coupled with respect to each other via the interface modules.

Abstract: A received optical signal is coherently demodulated and converted into electrical complex samples (p(n); (px(n), py(n)), which are dispersion compensated in a compensation filter (11). A control circuit (12, 13, 14, 15) calculates comparison values (R1, R2) from corrected samples q(n) and an estimated error value (?MIN). A plurality of compensation function (T(M)) is applied according to a predetermined dispersion (CD) range and after a second iteration is the compensation filter (11) set to an optimum compensation function (T(M)).

Abstract: A method and a device are provided for data processing. The data contains symbols and a control parameter is determined based on a correlation property of the symbols of the data. In this manner signal recovery is achieved that is robust against any kind of distortion and is fast enough to track time varying clocking disturbances. Further, a communication system is provided containing such a device.

Abstract: A received optical signal is coherently demodulated and converted into electrical complex samples (p(n); (px(n), py(n)), which are dispersion compensated in a compensation filter (11). A control circuit (12, 13, 14, 15) calculates comparison values (R1, R2) from corrected samples q(n) and an estimated error value (?MIN). A plurality of compensation function (T(M)) is applied according to a predetermined dispersion (CD) range and after a second iteration is the compensation filter (11) set to an optimum compensation function (T(M)).

Abstract: The present invention provides an apparatus, in particular an optical network unit, which comprises a first part operably coupled to an arm of an optical fiber network, the first part comprises an optical module including an optical-electric interface and/or an electric-optical interface locked on a preset wavelength band, and an interface module, and at least one second part operably coupled to a network entity of a communication network, each comprising a control unit, a signal processing unit and an interface module. One of the control units of the at least one second part is set by a optical line terminal of the optical fiber network as a master control unit configured to tune and control the optical module of the first part. The first part and the at least one second part are wireless coupled with respect to each other via the interface modules.

Abstract: A received optical signal is coherently demodulated and converted into electrical complex samples, which are dispersion compensated in a compensation filter. A control circuit calculates comparison values from corrected samples and an estimated error value. A plurality of compensation functions is applied according to a predetermined dispersion range and after a second iteration, the compensation filter is set to an optimum compensation function.

Abstract: A method and a device are provided for phase recovery of at least two channels comprising the steps of (i) a phase is estimated for each channel; (ii) the phase estimated of each channel is superimposed by a coupling factor with at least one other phase estimated. Further, a communication system is suggested comprising such a device.

Abstract: A received optical signal is coherently demodulated and converted into orthogonal x-polarization samples, and y-polarization samples. These samples are converted into signal x-samples and signal y-samples by an FIR butterfly filter. Correction values are calculated in an error calculating circuit of a control unit and added to filter transfer functions derived by a standard algorithm to determine corrected filter coefficients. Degenerate convergences calculating the transfer functions are avoided.

Abstract: The invention describes a method and an arrangement for transmitting an optical transmission signal with reduced polarisation-dependent loss. A first transmission signal component and a second orthogonal transmission signal component of the optical transmission signal are transmitted with a time difference between said transmission signal components.

Abstract: A signal processing method and a signal processing arrangement for coherent receivers are provided. The method includes the steps of receiving a coherent complex signal, extracting orthogonal in-phase and quadrature signal components from the coherent complex signal, quantizing the orthogonal signal components independently, combining the quantized orthogonal signal components as real and imaginary part of a complex number resulting in a first signal, and soft differential decoding the first signal resulting in a second signal.

Abstract: A receiver is provided for a quadrature-modulated signal, which can be divided into an inphase signal and a quadrature signal. The inphase signal is fed to first and third equalizers, and the quadrature signal is fed to second and fourth equalizers, wherein the first and second equalizers each perform a first equalization of the respective signal. An output of the first equalizer is connected to a second input of the fourth equalizer, which, by means of a second equalization of the quadrature signal, transmits an equalized quadrature signal as a function of the previously fed equalized inphase signal of the first equalizer. An output of the second equalizer is connected to the second input of the third equalizer, which, through a second equalization of the inphase signal, transmits an equalized inphase signal as a function of the previously fed equalized quadrature signal of the second equalizer.

Abstract: A received optical signal (SH, Sv) is coherently demodulated and converted into orthogonal x-polarisation samples (rx(n)), and y-polarisation samples (ry(n)). These samples are converted into signal x-samples zx(n) and signal y-samples zy(n) by an FIR butterfly filter (8). Correction values are calculated in an error calculating circuit (12) of a control unit (11) and added to filter transfer functions derived by a standard algorithm to determine corrected filter coefficients. Degenerate convergences calculating the transfer functions are avoided.

Abstract: A received optical signal is coherently demodulated and converted into electrical complex samples, which are dispersion compensated in a compensation filter. A control circuit calculates comparison values from corrected samples and an estimated error value. A plurality of compensation functions is applied according to a predetermined dispersion range and after a second iteration, the compensation filter is set to an optimum compensation function.

Abstract: A method and a device are provided for phase recovery of at least two channels comprising the steps of (i) a phase is estimated for each channel; (ii) the phase estimated of each channel is superimposed by a coupling factor with at least one other phase estimated. Further, a communication system is suggested comprising such a device.

Abstract: A method and a device are provided for data processing. The data contains symbols and a control parameter is determined based on a correlation property of the symbols of the data. In this manner signal recovery is achieved that is robust against any kind of distortion and is fast enough to track time varying clocking disturbances. Further, a communication system is provided containing such a device.

Abstract: The invention relates to a receiver for a quadrature-modulated signal, which can be divided into an inphase signal (I) and a quadrature signal (Q). The inphase signal (I) is fed to first and third equalizers (EZ1, EZ3), and the quadrature signal (Q) is fed to second and fourth equalizers (EZ2, EZ4), wherein the first and second equalizers (EZ1, EZ2) each perform a first equalization of the respective signal. An output of the first equalizer (EZ1) is connected to a second input of the fourth equalizer (EZ4), which, by means of a second equalization of the quadrature signal (Q), transmits an equalized quadrature signal (Q2) as a function of the previously fed equalized inphase signal (II) of the first equalizer (EZ1).

Abstract: Demodulation of CPM-modulated information symbols which are demodulated after being transmitted through an AWGN channel, using only partial whitened matched filtering, whereby finite pulses are produced which, however, are still accompanied by interferences in the form of remaining colored noise which can be approximately converted into white noise by a successive additional whitening filter so that the noise power will be minimized. For correcting the accompanying symbol interferences, a sequence estimation with reduced number of states follows.