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 (εMIN).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 for processing data in an optical network element is provided, wherein a multicarrier signal is linear pre-coded, and wherein the linear pre-coded signal is modulated. An according optical network element is also suggested.
Abstract:
Disclosed herein is a dual parallel Mach-Zehnder-modulator (DPMZM) device comprising a DPMZM 10 having first and second inner MZMs arranged parallel to each other. The first inner MZM generates an in-phase component EI of an optical signal in response to a first driving voltage VI, and the second inner MZM generates a quadrature component EQ of said optical signal in response to a second driving voltage VQ. Further disclosed is a calculation unit 52 configured for receiving an in-phase component yI and a quadrature component yQ_ of a desired base-band signal, and for calculating pre-distorted first and second driving voltages VI, VQ. The calculation of the pre-distorted first and second driving voltages VI, VQ is based on a model of said DPMZM 10 accounting for I-Q cross-talk, and using an algorithm that determines said first and second driving voltages VI, VQ each as a function of both of said in-phase and quadrature components yI, yQ of said base-band signal.
Abstract:
Component signal values are derived from component signals and fed to at least one fixed equalizer which generates equalizer output signals. The signals are fed to phase error detectors generating phase error signals. The phase error signals are combined with further phase error signals derived by further error detectors receiving signal values from further equalizers and/or the component signal values directly from sample units.
Abstract:
Component signal values are derived from component signals and fed to at least one fixed equalizer which generates equalizer output signals. The signals are fed to phase error detectors generating phase error signals. The phase error signals are combined with further phase error signals derived by further error detectors receiving signal values from further equalizers and/or the component signal values directly from sample units.
Abstract:
A method and device is provided for reducing optical transmission impairments, particularly nonlinear effects, of at least one link Said method comprising the following steps: extracting a phase information (Δθ) from an optical signal (120) received via that at least one link, determining a nonlinear coefficient (γ), associated with the at least one link, based on the phase information (Δθ), applying a control mechanism (202) using the nonlinear coefficient (γ). Furthermore, a communication system is suggested comprising said device.
Abstract:
Disclosed herein is a transponder (14), comprising a transmitter (18) for generating and transmitting an optical signal and a receiver (20), wherein said receiver (20) comprises a receiver input amplifier (40) at the receiver's input. The transponder further comprises a bypass line (46) configured to selectively feed an optical signal from said transmitter (18) to the receiver (20), and a control unit (22) configured for determining the performance of the transponder (14) in relation to an OSNR related parameter, by controlling the transponder to generate a noise signal to be received by the receiver (20), by operating the receiver input amplifier (40) to thereby cause ASE in the receiver input amplifier (40) and to determine a noise intensity value, generate a test signal at the transmitter (18) and to determine a signal intensity value and superimpose said noise signal and said test signal, or replicas thereof, to form a combined signal to be received by said receiver (20) and determining said performance related parameter based on said combined signal, wherein for generating said combined signal, said test signal is fed from the transmitter (18) to the receiver by means of said bypass line (46).