Abstract: A ring optical transmission network access node (ANi) comprises: two identical band splitters (BSa, BSb), each provided with homologous first, second and third ports (Ba, BWa, BPa; Bb, BWb, BPb), a first coupler (CW) coupling the second port (BWb) of the second splitter (BSb), on the one hand, to the second port (BWa) of the first splitter (BSa) via a first channel and, on the other hand, to an access point (A2) via a second channel, a second coupler (CP) coupling the third port (BPa) of the first splitter (BSa), on the one hand, to the third port (BPb) of the second band splitter (BSb) via a first channel and, on the other hand, to another access point (A1) via a second channel. Such nodes enable the implementation of a passive ring network comprising only one fiber and in which the coupling ratios of the couplers (CW, CP) are optimized for two opposite traffic propagation directions. Application in particular to optical fiber metropolitan access networks, with broken fiber protection device.

Abstract: A WDM network (R) comprises an optical fiber (F) connected to a hub (H) via an input of a demultiplexer (DX) having N outputs to communications stations (Si-Sn) able to deliver and/or receive spectral multiplexes of modulated optical signals with different wavelengths, via coupling means (CP, CP?, MXB). The communications stations (Sn?1) are adapted to deliver spectral multiplexes of modulated optical signals from a given one of P disjoint bands of wavelengths. At least one of the coupling means (MXB) is a 2×1 band multiplexer comprising i) an output connected to a downstream portion of the optical fiber (F), ii) a first input connected to one of the stations (then referred to as the “primary” station) and adapted to its band of wavelengths, and iii) a second input connected to an upstream portion of the optical fiber (F) and adapted to channels having wavelengths different from those of the channels passing through the first input.

Abstract: A Laser device for optical packet data transmission in TDM-systems is provided. The device comprises a laser light source for outputting laser light beam and a laser driver for driving the laser light source; an optical modulator which receives and modulates the laser light beam output by the laser light source; a packet data source for outputting a packet data stream; and a modulator driver for receiving the packet data stream output by the packet data source and for driving the optical modulator in response to the packet data stream resulting in that the optical modulator modulates the laser light beam in response to the packet data stream. A filter generates an envelope signal of the data packets in the packet data stream, and a switch switches the laser driver in response to the envelope signal.

Abstract: An optical telecommunications network (1000), of metropolitan area type, having a ring type core (10), and secondary rings (41, 42; 43, 44). In each sending access node (11), transmitters (111) for sending information-carrying optical signals use a wavelength belonging to a group of wavelengths dedicated to the secondary ring (41, 42) to which this sending access node (11) is connected. In each destination access node (21), receivers (212) are capable of receiving all the wavelengths used by sending nodes (11) of the network. Communication nodes (1, 2) comprise all-optical devices (100, 101, 10; 201, 20) for inserting, into the core fiber (10), optical signals sent by a sending access node connected to the communication nodes. Optical couplers (31, 32), for taking from the core fiber (10) a so-called representative signal formed of a fraction of the power of each information-carrying signal, are respectively coupled to the receivers of the destination nodes.

Abstract: A ring optical transmission network access node (ANi) comprises: two identical band splitters (BSa, BSb), each provided with homologous first, second and third ports (Ba, BWa, BPa; Bb, BWb, BPb), a first coupler (CW) coupling the second port (BWb) of the second splitter (BSb), on the one hand, to the second port (BWa) of the first splitter (BSa) via a first channel and, on the other hand, to an access point (A2) via a second channel, a second coupler (CP) coupling the third port (BPa) of the first splitter (BSa), on the one hand, to the third port (BPb) of the second band splitter (BSb) via a first channel and, on the other hand, to another access point (A1) via a second channel. Such nodes enable the implementation of a passive ring network comprising only one fiber and in which the coupling ratios of the couplers (CW, CP) are optimized for two opposite traffic propagation directions. Application in particular to optical fiber metropolitan access networks, with broken fiber protection device.

Abstract: A WDM network (R) comprises an optical fiber (F) connected to a hub (H) via an input of a demultiplexer (DX) having N outputs to communications stations (Si-Sn) able to deliver and/or receive spectral multiplexes of modulated optical signals with different wavelengths, via coupling means (CP, CP?, MXB). The communications stations (Sn?1) are adapted to deliver spectral multiplexes of modulated optical signals from a given one of P disjoint bands of wavelengths. At least one of the coupling means (MXB) is a 2×1 band multiplexer comprising i) an output connected to a downstream portion of the optical fiber (F), ii) a first input connected to one of the stations (then referred to as the “primary” station) and adapted to its band of wavelengths, and iii) a second input connected to an upstream portion of the optical fiber (F) and adapted to channels having wavelengths different from those of the channels passing through the first input.

Abstract: The invention relates to an optical amplifier device including a semiconductor optical amplifier component (1) including a guide active structure (12), characterized in that the guide active structure (12) is subjected to a stress external to said component (1) coming from integrating said component (1) in said device, and in that said component (1) has a controlled sensitivity to the state of polarization of the light to be amplified in order to render the gain of said optical amplifier device insensitive to the polarization of said light to be amplified.

Abstract: The invention relates to a laser device for optical packet data transmission. Such devices are basically known in the art and comprise a laser light source for outputting a laser light beam and a laser driver for driving said laser light source. The laser device further comprises an optical modulator means for modulating a packet data stream onto said laser light beam. The optical modulator means presently available on the market, only have a low extinction rate; consequently residual light is output by said optical modulator means, even if a logical zero shall be transmitted.

Abstract: This optical telecommunications network (1000), of metropolitan area type, comprises a ring type core (10), and secondary rings (41, 42; 43, 44). In each sending access node (11), means (111) for sending information-carrying optical signals use a wavelength belonging to a group of wavelengths dedicated to the secondary ring (41, 42) to which this sending access node (11) is connected. In each destination access node (21), receiving means (212) are capable of receiving all the wavelengths used by sending nodes (11) of the network. Insertion means (1, 2) comprise all-optical means (100, 101, 10; 201, 20) for inserting, into the core fibre (10), optical signals sent by a sending access node connected to these insertion means. Extraction means (31, 32) comprise optical couplers for taking from the core fibre (10) a so-called representative signal formed of a fraction of the power of each information-carrying signal, these couplers being respectively coupled to said receiving means of the destination nodes.

Abstract: In order to be able to use a semiconductor light amplifier of conventional type and operating under gain saturation conditions while nevertheless providing constant gain for an optical signal to be amplified, the device comprises means for producing a compensation light wave and coupling means for injecting the optical signal to be amplified and the compensation light wave into the amplifier. The compensation light wave presents amplitude modulation such that when combined with the optical signal to be amplified the overall amplitude modulation is eliminated or at least attenuated. The device is applicable to optical transmission systems operating at a single wavelength or with wavelength division multiplexing.

Abstract: The invention relates to an optical amplifier device including a semiconductor optical amplifier component (1) including a guide active structure (12), characterized in that the guide active structure (12) is subjected to a stress external to said component (1) coming from integrating said component (1) in said device, and in that said component (1) has a controlled sensitivity to the state of polarization of the light to be amplified in order to render the gain of said optical amplifier device insensitive to the polarization of said light to be amplified.

Abstract: The invention relates to a semi-conductor optical amplifier comprising an active waveguide and a laser oscillator structure framing the active waveguide, characterized in that it includes at least one input for control of the gain at the threshold of the said laser structure to enable adjustment of the value of the amplifier's gain. This amplifier is intended to be used in an optical system which includes means of regulation capable of acting on the control inputs of the amplifier in response to the optical power of the carrier wave of an output signal to enable adjustment of the value of the amplifier's gain. This optical system makes it possible particularly to obtain power equalization of a signal at the entry to a telecommunication system.

Abstract: An active structure in the semiconductor die of an amplifier or converter includes a plurality of stacked active layers with different compositions. The different compositions lead to a spectral offset between the respective gain bands of the layers which widens the gain band of the amplifier or the optical bandwidth of the converter. Applications include fiber optic telecommunication networks.