Alcatel

Alcatel Lucent

Nokia Solutions and Networks Oy

Fred Buchali

Roman Dischler

Henning Bülow

Laurent Schmalen

Andreas Leven

Ulrich Gebhard

Dieter Ferling

Lars Dembeck

Axel Klekamp

Vahid Aref

Stenio Magalhaes Ranzini

Hu Qian

Karsten Schuh

A coherent optical data receiver having a digital signal processor (DSP) capable of mitigating equalization-enhanced phase noise (EEPN). In an example embodiment, the DSP mitigates EEPN by applying individual phase adjustments to different spectral slices of a digital stream carrying CD-compensated digital samples of the received optical data signal. In different embodiments, the individual phase adjustments can be dynamically selected based on symbol decisions taken prior to EEPN mitigation, based on transmitted pilot symbols, and/or using moving averages computed for different spectral slices. Some embodiments are suitable for handling polarization-division-multiplexed optical data signals. Some embodiments are advantageously capable of producing an effective SNR gain of approximately 1 dB.

Mitigation of equalization-enhanced phase noise in a coherent optical receiver

Embodiments relate to a method for generating a second data packet for a second network layer from a first data packet including a first header portion with information related to a first network layer higher than the second network layer. The method comprises generating, based on the first header portion, a second header portion including information related to the second network layer and generating a payload portion including the first data packet. The method further comprises generating the second data packet for the second network layer by linking the second header portion and the payload portion.

Method and an apparatus for generating a second data packet from a first data packet

Embodiments relate to an apparatus for a regenerative network node between a first and a second link portion. The apparatus comprises an input configured to receive, from the first link portion, a signal impaired by the first link portion, the signal including a data packet with a Forward Error Correction (FEC) encoded payload portion and a header portion. The apparatus comprises a signal regeneration unit configured to mitigate signal impairments of the first link portion to provide a regenerated FEC encoded payload portion. The apparatus comprises a processing unit configured to extract destination information in the data packet's header portion. If extracted destination information indicates that the data packet's destination is the regenerative network node, the data packet's regenerated FEC encoded payload portion is forwarded to a decoding unit of the regenerative network node. Else, the data packet's regenerated FEC encoded payload portion is forwarded to the second link portion.

Apparatus and a method for a regenerative network node between a first and a second link portion

In order to achieve a higher spectral efficiency of OFDM sub-bands, optical signals using orthogonal frequency division multiplexing are transmitted through an optical network in the form of a continuous waveband optical signal. An optical add/drop multiplexer () splits the continuous waveband optical signal into an express path and a drop path. A band pass filter () is provided in the drop path to extract a sub-band carrying at least one of said OFDM modulated optical signals (DROP). The band pass filter () has a filter bandwidth that covers the sub-band to be extracted. A band-stop filter () is provided in the express path to remove the sub-band to be extracted from the continuous waveband optical signal (IN). The band stop filter () has a filter bandwidth which is narrower than the band pass filter (). An OFDM modulated optical add signal (ADD) can be added into the wavelength gap created through the band stop filter (). The sub-band carrying the optical add signal (ADD) occupies a wavelength range which is completely covered by the filter bandwidth of the band-stop filter (). The difference between the filter bandwidths of the band pass filter () and the band stop filter () corresponds preferably to the slope of the filter edges of the filters ().

Optical transmission method and apparatus using OFDM

A receiver device for optical data signals, in particular optical data signals in the Gb/s range, comprising an opto-electrical conversion unit, a frequency multiplicator unit () for frequency-multiplying the converted electrical data signal, and a clock recovery unit is characterized in that the frequency multiplicator unit () performs a frequency multiplication by a factor of n, with n being a natural number larger than 2. The receiver device has an improved tolerance on dispersion as far as generating a clock line is concerned.

Data transmission system and receiver device for optical data signals

A polarization mode dispersion (PMD) controller device for controlling the state of polarization of an optical light wave comprising a dispersion compensation unit () and an adaptation control unit (), wherein the dispersion compensation unit () comprises a multitude of compensation stages processing the optical light wave, and wherein the adaptation control unit () controls the dispersion compensation unit () is characterized in that at least one feed-forward signal tap (--) is provided tapping the optical light wave inserted into one of the compensation stages, that the feed-forward signal(s) is(are) fed into a distortion analyzer unit () and that the distortion analyzer unit () provides the adaptation control unit () with information about the incoming optical light wave. It accelerates the adaptation speed and lowers the costs of a high-speed PMD controller device.

Polarization mode dispersion controller device and method for its operation

A process is proposed for recovering disturbed digital signals, wherein the electrical signals pass through a feedback equalizer and an analogue control of the setting parameters of the equalizers is performed. A pseudo-error monitor, which facilitates a high-speed adjustment of decision element thresholds, is also provided.

Process for recovering digital optical signals and a feedback decision circuit

To protect the high frequency circuits arranged in a casing and which are operated at frequencies of &gt;1 GHz to 100 GHz against inner electromagnetic perturbing radiation, the complete circuit (1) is equipped on both sides with a large area layer (3, 4) which absorbs electrical fluctuations. The layer (4), made from a material which absorbs electrical fluctuations, such as silicon with average conductivity, is arranged below the circuit carrier (1). The circuit carrier (1) with the components (5) is encapsulated by a dielectric material such as silicon sealing compound or epoxy resin. The layer (3) made from a sealing compound which absorbs electrical fluctuations, such as silicon filled with iron powder, is arranged above the encapsulated circuit carrier (1, 2).

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Waiblingen, Germany

Fred Buchali