Abstract: A device for inserting/extracting at least one optical subband into an optical channel consisting of a plurality of optical subbands. The device includes an extraction means that is capable of extracting a first optical subband belonging to the optical channel, a suppression means that is arranged so as to obtain a filtered optical channel from the optical channel wherein at least one second subband is suppressed, and a coupling means that is capable of inserting a replacement optical subband in place of the second subband in the filtered optical channel so as to obtain a modified optical channel. The device moreover relates to an optical insertion/extraction switcher, using one or more insertion/extraction devices, and to the corresponding insertion/extraction methods.

Abstract: The differential group delay is measured in an optical fiber connection for an optical signal undergoing a phase modulation BPSK or DPSK by a digital signal at a given rate. A polarization controller at an emerging end of the connection scans polarization states of the modulated optical signal. An emulator iteratively introduces an additional delay in the modulated optical signal emerging from the connection and combines the delayed modulated optical signal and the non delayed modulated optical signal which are both polarized along two orthogonal axes into a resulting optical signal. A polarization controller and a fixed polarizer select a polarization state in the resulting optical signal along one of bisecting lines of the orthogonal axes into a linearly polarized signal. An eye diagram or a spectrum of the polarized signal is acquired by a digital oscilloscope or an optical spectrum analyzer to determine the differential group delay.

Abstract: A passive optical network is provided, which includes an optical central office connected to a line termination device by a branch of the network including a passive amplification medium. The central office is adapted to send/receive a first data optical signal and has a first amplifier for sending a second amplification optical signal. The second signal exciting the amplification medium to amplify the optical power of an optical signal. The line termination device is adapted to receive the first optical signal, modulate the second amplification optical signal; and inject the modulated second signal into the network.

Abstract: The apparatus includes a pulse emitter and at least one line fiber for conveying at least one pulse in the line fiber. A spreader module for linearly spreading pulses is provided including a propagation medium that is dispersive and linear. The propagation medium presents accumulated chromatic dispersion that is high enough to lower the peak power of the pulse to below a predetermined threshold, where a signal above the threshold is subjected to non-linear distortion in the line fiber. The spreader module is disposed between the emitter and the line fiber.

Abstract: The invention concerns a device for temporal subsampling of an OTDM optical signal at a predetermined subsampling frequency, comprising a generator (10) for generating clock pulses transmitted at the predetermined subsampling frequency and at a conversion wavelength ?H and a wavelength converter device (16) adapted to receive at its input the OTDM optical signal and the clock pulses in order to deliver at its output a subsampled OTDM optical signal at the conversion wavelength. The converter device comprises a linear optical amplifier (18) adapted to receive the OTDM optical signal and the clock pulses propagating in the opposite direction, the maximum linear power of the conversion being adjusted so that it can be less than the peak power of the OTDM optical signal, and a converter (20) of phase modulation into amplitude modulation.

Abstract: The invention relates to a device and a method for converting WDM signals into an OTDM signal. The device comprises shifting means (102, 103, 104) adapted to introduce a time shift between the pulses of the WDM signals carried by the optical carriers, modulation means (112, 113, 114) adapted to modify the optical power of the WDM signals, an optical temporal multiplexer/demultiplexer (120), a birefringent propagation medium (130) into which the WDM signals are injected in such a manner as to achieve a soliton trapping phenomenon, and absorption means (140) adapted to introduce optical losses into the components of the OTDM signal. This device performs WDM/OTDM conversion at very high bit rates. It also performs OTDM/WDM conversion. It is intended to be installed in long-haul telecommunication networks.

Abstract: The invention relates to a passive optical network comprising an optical exchange linked by at least one optical fiber to at least one line termination device of said network, able to transmit a downlink optical signal phase-modulated in NRZ-DPSK format and to receive an uplink optical signal. According to the invention, said line termination device comprises means of converting the transmitted downlink optical signal phase-modulated in NRZ-DPSK format into an optical data signal amplitude-modulated in duobinary modulation format and means of generating an uplink optical signal phase-modulated in NRZ-DPSK format from the downlink optical signal phase-modulated in NRZ-DPSK format. The optical exchange is able to convert the uplink optical signal phase-modulated in NRZ-DPSK format into an optical data signal amplitude-modulated in duobinary modulation format.

Abstract: The differential group delay is measured in an optical fiber connection for an optical signal undergoing a phase modulation BPSK or DPSK by a digital signal at a given rate. A polarization controller at an emerging end of the connection scans polarization states of the modulated optical signal. An emulator iteratively introduces an additional delay in the modulated optical signal emerging from the connection and combines the delayed modulated optical signal and the non delayed modulated optical signal which are both polarized along two orthogonal axes into a resulting optical signal. A polarization controller and a fixed polarizer select a polarization state in the resulting optical signal along one of bisecting lines of the orthogonal axes into a linearly polarized signal. An eye diagram or a spectrum of the polarized signal is acquired by a digital oscilloscope or an optical spectrum analyzer to determine the differential group delay.

Abstract: An optical signal processor device (14) intended to be fitted to means (10) for optically transmitting an information-carrying signal (S) comprises means (20, 22) for suppressing backscattered signals (RS) in the optical transmission means (10), an optical propagation medium (16) intended to be connected in parallel with the optical transmission means (10), divertor means (18, 20) for diverting the backs-propagated signals (P, RS) in the optical transmission means (10) into the optical propagation medium (16), and signal discrimination means (22) connected to the optical propagation medium (16).

Abstract: A non-linear phase noise limiter device limits the non-linear phase noise that affects a phase-modulated input optical signal of constant mean amplitude conveyed over a transmission line. The device is placed at a zero dispersion point of the transmission line, and it is suitable for suppressing amplitude fluctuations about a mean value in said optical signal.

Abstract: A passive optical network is provided, which includes an optical central office connected to a line termination device by a branch of the network including a passive amplification medium. The central office is adapted to send/receive a first data optical signal and has a first amplifier for sending a second amplification optical signal. The second signal exciting the amplification medium to amplify the optical power of an optical signal. The line termination device is adapted to receive the first optical signal, modulate the second amplification optical signal; and inject the modulated second signal into the network.

Abstract: The invention relates to a device for regenerating the phase of an optical signal carrying an information encoded by phase modulation of said signal, the device comprising an optical modulation converter for converting the signal carrying the information encoded by phase modulation into at least one secondary signal carrying said information encoded by amplitude modulation, and at least one module for optically regenerating the amplitude of the secondary signal.

Abstract: The invention relates to a device and a method for converting WDM signals into an OTDM signal. The device comprises shifting means (102, 103, 104) adapted to introduce a time shift between the pulses of the WDM signals carried by the optical carriers, modulation means (112, 113, 114) adapted to modify the optical power of the WDM signals, an optical temporal multiplexer/demultiplexer (120), a birefringent propagation medium (130) into which the WDM signals are injected in such a manner as to achieve a soliton trapping phenomenon, and absorption means (140) adapted to introduce optical losses into the components of the OTDM signal. This device performs WDM/OTDM conversion at very high bit rates. It also performs OTDM/WDM conversion. It is intended to be installed in long-haul telecommunication networks.

Abstract: This device for optically regenerating pulses includes a synchronous intensity modulator to provide time synchronization for pulses passing through it and to stabilize intensity fluctuations in the pulses. In addition, it includes noise suppression circuitry in the form of a saturable absorber that is distinct from the synchronous intensity modulator and the intensity fluctuations stabilizer.

Abstract: A device and a method for converting WDM signals into an OTDM signal. A time shift is introduced between the pulses of the WDM signals carried by the optical carriers. A modulation means is (112, 113, 114) adapted to modify the optical power of the WDM signals, and an optical temporal multiplexer/ demultiplexer (120) is provided. The WDM signals are injected into a birefringent propagation medium (130) in such a manner as to achieve a soliton trapping phenomenon. An absorption means (140) is adapted to introduce optical losses into the components of the OTDM signal. This technique performs WDM/OTDM conversion at very high bit rates. It also performs OTDM/WDM conversion. It is intended to be installed in long-haul telecommunication networks.

Abstract: System and method of transmitting downlink and uplink data traffic between a central office terminal (15) and a plurality of customer terminals (17) Interconnected by means of a passive optical access network (5), comprising the following steps: sending data carried by an amplitude-division multiplexed optical signal (S) including a plurality of amplitudes and having a single wavelength to said plurality of customer terminals (17); converting the single wavelength of said optical signal (S) sent by said central office terminal (15) into a plurality of wavelengths according to said plurality of amplitudes, by spectrum shifting, thereby forming a wavelength-division multiplexed optical signal, so that said data is received by said plurality of customer terminals (17) in a plurality of optical signals (S1, . . .

Abstract: The invention relates to in particular to a device for optically regenerating pulses, the device comprising an optical bandpass filter adapted for providing time synchronization and intensity stabilization of dispersion-managed soliton pulses. The device further comprises noise suppression means distinct from the bandpass filter.

Abstract: The invention concerns a device for temporal subsampling of an OTDM optical signal at a predetermined subsampling frequency, comprising a generator (10) for generating clock pulses transmitted at the predetermined subsampling frequency and at a conversion wavelength ?H and a wavelength converter device (16) adapted to receive at its input the OTDM optical signal and the clock pulses in order to deliver at its output a subsampled OTDM optical signal at the conversion wavelength. The converter device comprises a linear optical amplifier (18) adapted to receive the OTDM optical signal and the clock pulses propagating in the opposite direction, the maximum linear power of the conversion being adjusted so that it can be less than the peak power of the OTDM optical signal, and a converter (20) of phase modulation into amplitude modulation.

Abstract: The invention relates to an apparatus for transmitting a signal through an optical data transmission network, the apparatus comprising a pulse emitter (10) and at least one line fiber (12) for conveying at least one pulse (30) in said line fiber. The apparatus further comprises a spreader module (14) for linearly spreading pulses, said spreader module comprising a propagation medium that is dispersive and linear, said propagation medium presenting accumulated chromatic dispersion that is high enough to lower the peak power (PC) of the pulse to below a predetermined threshold (S), where a signal above said threshold is liable to be subjected to non-linear distortion in the line fiber, said spreader module (14) being disposed between the emitter (10) and the line fiber (12).

Abstract: An optical signal processor device (14) intended to be fitted to means (10) for optically transmitting an information-carrying signal (S) comprises means (20, 22) for suppressing backscattered signals (RS) in the optical transmission means (10), an optical propagation medium (16) intended to be connected in parallel with the optical transmission means (10), divertor means (18, 20) for diverting the backs-propagated signals (P, RS) in the optical transmission means (10) into the optical propagation medium (16), and signal discrimination means (22) connected to the optical propagation medium (16).