Abstract: An amplification device includes an element for splitting an input optical signal into first and second optical signals having first and second polarization modes, first and second amplification stages each including polarized SOAs for amplifying the first and second optical signals depending on driving currents, an intermediate processing stage for compensating optical characteristics of the optical gain bandwidth of the first amplification stage depending on driving currents, an element for combining the first and second optical signals outputted by the second amplification stage to produce an output optical signal, and a control means producing the driving currents depending on information representative of powers of the first and second optical signals before the polarized SOAs of each amplification stage and on a targeted power of the output optical signal.

Abstract: A method and device for optical data transmission are disclosed. Data bits are transmitted in the form of data symbols, by modulating an optical signal in dependence on the data bits and in accordance with two or more constellation schemes. The data bits are transmitted, by generating first data symbols, which represent respective sets of data bits containing an even number of data bits. The first data symbols are generated, by modulating the optical signal in accordance with a first constellation scheme. Furthermore, the data bits are transmitted, by generating second data symbols, which represent respective sets of data bits having an odd number of data bits. The second data symbols are generated, by modulating the optical signal in accordance with a second constellation scheme. The first and the second data symbols are generated at a predefined symbol rate, such that the first and the second data symbols are interleaved in time.

Abstract: A modular optical device having a set of optoelectronic modules that enables the device to operate, e.g., as a WDM or multichannel transceiver. In an example embodiment, the set of optoelectronic modules includes a laser module, a modulator module, and an optical-to-electrical converter module, all mounted on the same circuit board and optically and electrically connected for the intended application. Each of the optoelectronic modules comprises a respective stack of integrated circuits, at least one of which is a photonic integrated circuit (PIC). Some of the PICs may be configurable for different applications, with the configuration setup being carried out using electrical control signals and/or optical connections of the PICs.

Abstract: A technique is provided for a receiver of an optical signal. The technique includes an apparatus that is configured to input digitized samples of the optical signal at a first sampling rate. The apparatus is further configured to filter the digitized samples based on a plurality of filter coefficients to obtain filtered samples of the optical signal at a second sampling rate. The second sampling rate is different from the first sampling rate. The apparatus is further configured to output the filtered samples of the optical signal at the second sampling rate.

Abstract: A modular optical device having a set of optoelectronic modules that enables the device to operate, e.g., as a WDM or multichannel transceiver. In an example embodiment, the set of optoelectronic modules includes a laser module, a modulator module, and an optical-to-electrical converter module, all mounted on the same circuit board and optically and electrically connected for the intended application. Each of the optoelectronic modules comprises a respective stack of integrated circuits, at least one of which is a photonic integrated circuit (PIC). Some of the PICs may be configurable for different applications, with the configuration setup being carried out using electrical control signals and/or optical connections of the PICs.

Abstract: An amplification device includes an element for splitting an input optical signal into first and second optical signals having first and second polarization modes, first and second amplification stages each including polarized SOAs for amplifying the first and second optical signals depending on driving currents, an intermediate processing stage for compensating optical characteristics of the optical gain bandwidth of the first amplification stage depending on driving currents, an element for combining the first and second optical signals outputted by the second amplification stage to produce an output optical signal, and a control means producing the driving currents depending on information representative of powers of the first and second optical signals before the polarized SOAs of each amplification stage and on a targeted power of the output optical signal.

Abstract: A technique is provided for a receiver of an optical signal. The technique includes an apparatus that is configured to input digitized samples of the optical signal at a first sampling rate. The apparatus is further configured to filter the digitized samples based on a plurality of filter coefficients to obtain filtered samples of the optical signal at a second sampling rate. The second sampling rate is different from the first sampling rate. The apparatus is further configured to output the filtered samples of the optical signal at the second sampling rate.

Abstract: A technique is provided for provisioning optical connections in an optical network.

Abstract: An optical transmitter for transmitting a multilevel amplitude-shift-keying modulated signal includes an optical modulator for modulating an optical signal with a multilevel amplitude-shift-keying modulation, and a spectral filter adapted to increase a high-frequency component of the modulated optical signal relatively to a central frequency component. The multilevel ASK modulation is quaternary ASK and the symbol rate of the optical modulator is above 40 Gbaud. An optical link connects the optical transmitter to a quadratic direct detection optical receiver.

Abstract: An exemplary method and apparatus are provided for high efficiency wavelength division multiplexing (WDM) optical communication systems. An optical transmitter adapted to transmit an optical signal on an optical WDM transmission channel to a corresponding optical receiver is described. The optical transmitter comprises a symbol generation unit adapted to convert input data into a sequence of data symbols at a symbol rate B; with B being a real number greater zero; an amplitude modulation unit adapted to modulate an amplitude of every Nth data symbol in a sequence derived from the sequence of data symbols, thereby creating a modulated sequence of data symbols; wherein N is an integer; wherein N>2; and a digital-to-optical converter adapted to convert a sequence derived from the modulated sequence of data symbols into an optical signal to be transmitted to the optical receiver.

Abstract: A method and device for optical data transmission are disclosed. Data bits are transmitted in the form of data symbols, by modulating an optical signal in dependence on the data bits and in accordance with two or more constellation schemes. The data bits are transmitted, by generating first data symbols, which represent respective sets of data bits containing an even number of data bits. The first data symbols are generated, by modulating the optical signal in accordance with a first constellation scheme. Furthermore, the data bits are transmitted, by generating second data symbols, which represent respective sets of data bits having an odd number of data bits. The second data symbols are generated, by modulating the optical signal in accordance with a second constellation scheme. The first and the second data symbols are generated at a predefined symbol rate, such that the first and the second data symbols are interleaved in time.

Abstract: To that end, it is an object of the invention to provide a method for converting a high-speed digital signal in the form of optical pulses intended to be transmitted within optical guides, within which the signal is converted into a series of optical pulses in three possible phase states (?/6, 5?/6, ??/2) separated from one another two-by-two by an angle greater than ?/2.

Abstract: An optical transmitter for transmitting a multilevel amplitude-shift-keying modulated signal includes an optical modulator for modulating an optical signal with a multilevel amplitude-shift-keying modulation, and a spectral filter adapted to increase a high-frequency component of the modulated optical signal relatively to a central frequency component. The multilevel ASK modulation is quaternary ASK and the symbol rate of the optical modulator is above 40 Gbaud. An optical link connects the optical transmitter to a quadratic direct detection optical receiver.

Abstract: An exemplary method and apparatus are provided for high efficiency wavelength division multiplexing (WDM) optical communication systems. An optical transmitter adapted to transmit an optical signal on an optical WDM transmission channel to a corresponding optical receiver is described. The optical transmitter comprises a symbol generation unit adapted to convert input data into a sequence of data symbols at a symbol rate B; with B being a real number greater zero; an amplitude modulation unit adapted to modulate an amplitude of every Nth data symbol in a sequence derived from the sequence of data symbols, thereby creating a modulated sequence of data symbols; wherein N is an integer; wherein N>2; and a digital-to-optical converter adapted to convert a sequence derived from the modulated sequence of data symbols into an optical signal to be transmitted to the optical receiver.

Abstract: A data transmitter (A, B, C, D) wherein, in a first operating mode, the first and second carrier signals are mutually phase-shifted, and the data module generates said first and second data signals based on different data, so as to produce, at the transmitter's output, a modulated signal exhibiting a first constellation of states (A, B, C, D) in a complex plane, and, in a second operating mode of the transmitter, the data module generates said first and second data signals correlated with one another based on common data, so as to produce, at the transmitter's output, a modulated signal exhibiting a second constellation of states (A, D; E, F) in the complex plane that is more reduced and more dispersed then said first constellation of states.

Abstract: The embodiments of the present invention describe a method for optimizing the capacity of an optical communication network that uses wavelength division multiplexing, wherein the spectral distribution of the signals intended to be transmitted over a plurality of channels is done dynamically through the use of a variable spectrum grid whose spectral spacings between two successive channels are determined based on the spectral width of said signals and in which dynamic filtering of said signals is carried out before their transmission in order to adjust their spectral width based on the available spectral space, and thereby reduce crosstalk between adjacent channels when the signals are transmitted.

Abstract: To that end, it is an object of the invention to provide a method for converting a high-speed digital signal in the form of optical pulses intended to be transmitted within optical guides, within which the signal is converted into a series of optical pulses in three possible phase states (?/6, 5?/6, ??/2) separated from one another two-by-two by an angle greater than ?/2.

Abstract: A method for monitoring a system using optical reflectometry comprises: receiving a first optical response signal coming from the system in response to a first optical excitation signal, said first excitation signal carrying a first numeric sequence (A), receiving a second optical response signal coming from the system in response to a second optical excitation signal, said second excitation signal carrying a second numeric sequence (1A, B), and determining correlations between said optical response signals and said numeric sequences in order to detect a singularity of the system. The first and second excitation signals are transmitted simultaneously within the optical system on separate carrier wavelengths ?0, ?1) by wavelength division multiplexing, and the first and second response signals are received simultaneously on said separate carrier wavelengths.

Abstract: The embodiments of the present invention describe a method for optimizing the capacity of an optical communication network that uses wavelength division multiplexing, wherein the spectral distribution of the signals intended to be transmitted over a plurality of channels is done dynamically through the use of a variable spectrum grid whose spectral spacings between two successive channels are determined based on the spectral width of said signals and in which dynamic filtering of said signals is carried out before their transmission in order to adjust their spectral width based on the available spectral space, and thereby reduce crosstalk between adjacent channels when the signals are transmitted.

Abstract: The invention relates to a modulation scheme for optical communication, in particular for fiber optics communication. According to invention, an optical signal is generated, both phase and polarization of which modulated in dependency of the data to be transmitted. Preferably, the generated optical signal comprises a sequence of symbols (22a-22k) and each symbol (22a-22k) has one of two different phase states and one of two different orthogonal polarization states. Bits of the data stream to be transmitted are encoded both in the phase state of a symbol (or in the phase state difference between subsequent symbols) and in the polarization state of the symbol (or in the polarization state difference between the subsequent symbols).