Abstract: A free space optical FSO space data transmission system includes a first ground or aeronautical optical terminal, a second optical terminal housed on board a satellite, and a relay platform. The relay platform is configured so as to move at an altitude higher than that of clouds and atmospheric turbulence, so as to receive the data transmitted by the first terminal in the MWIR/LWIR domain of long wave infrared LWIR wavelengths and/or medium wave infrared MWIR wavelengths, and retransmit the received data to the second terminal in the domain of short wave infrared SWIR wavelengths, and/or receive the data transmitted by the second terminal in the domain of short wave infrared SWIR wavelengths, and retransmit the received data to the first terminal in the MWIR/LWIR domain of long wave infrared LWIR wavelengths and/or medium wave infrared MWIR wavelengths.

Abstract: A free space optical FSO space data transmission system includes a first ground or aeronautical optical terminal, a second optical terminal housed on board a satellite, and a relay platform. The relay platform is configured so as to move at an altitude higher than that of clouds and atmospheric turbulence, so as to receive the data transmitted by the first terminal in the MWIR/LWIR domain of long wave infrared LWIR wavelengths and/or medium wave infrared MWIR wavelengths, and retransmit the received data to the second terminal in the domain of short wave infrared SWIR wavelengths, and/or receive the data transmitted by the second terminal in the domain of short wave infrared SWIR wavelengths, and retransmit the received data to the first terminal in the MWIR/LWIR domain of long wave infrared LWIR wavelengths and/or medium wave infrared MWIR wavelengths.

Abstract: An elementary device for coherently recombining a first elementary beam and a second elementary beam, includes a first input and a second input, into which are respectively injected the first elementary beam and the second elementary beam to be recombined, an output that delivers an output beam corresponding to the coherent recombination of the first and second elementary beams, a delay line placed on one of the paths of said elementary beams and configured to induce a variable delay on said path, a variable coupler comprising a first 2×2 combiner, a phase modulator and a second 2×2 combiner, a control detector configured to generate, from the complementary beam, an error signal (?), a feedback loop configured to determine, from the error signal, the delay and the phase difference to be applied.

Abstract: A photonic frequency converter includes an electro-optical intensity modulator having an optical input, one optical output and at least one RF input for receiving two modulation radiofrequency signals at different frequencies; a set of optical sources that are configured to generate optical signals at at least two different wavelengths, the signals being modulated by respective local-oscillator signals at least two of which have different frequencies; and an optical multiplexer arranged to multiplex the optical signals and to inject them into the optical input of the modulator. A method for converting frequency by means of such a converter is also provided.

Abstract: An elementary device for coherently recombining a first elementary beam and a second elementary beam, includes a first input and a second input, into which are respectively injected the first elementary beam and the second elementary beam to be recombined, an output that delivers an output beam corresponding to the coherent recombination of the first and second elementary beams, a delay line placed on one of the paths of said elementary beams and configured to induce a variable delay on said path, a variable coupler comprising a first 2×2 combiner, a phase modulator and a second 2×2 combiner, a control detector configured to generate, from the complementary beam, an error signal (?), a feedback loop configured to determine, from the error signal, the delay and the phase difference to be applied.

Abstract: A photonic frequency converter includes an electro-optical intensity modulator having an optical input, one optical output and at least one RF input for receiving two modulation radiofrequency signals at different frequencies; a set of optical sources that are configured to generate optical signals at at least two different wavelengths, the signals being modulated by respective local-oscillator signals at least two of which have different frequencies; and an optical multiplexer arranged to multiplex the optical signals and to inject them into the optical input of the modulator. A method for converting frequency by means of such a converter is also provided.

Abstract: An inter-satellite communication device for satellites orbiting within a constellation of satellites comprises at least one optical terminal dedicated to intra-orbital plane communication links and at least one optical terminal dedicated to inter-orbital plane communication links, each optical terminal dedicated to intra-orbital plane communications configured to transmit and receive optical signals with an optical terminal of an identical satellite orbiting in the same orbital plane, each optical terminal dedicated to inter-orbital plane communications configured to transmit and receive optical signals with an optical terminal of an identical satellite in an orbital plane adjacent over the entirety of its orbit in its orbital plane and each optical terminal dedicated to inter-orbital plane communications having a field of regard such that the half-angle at the vertex of the latter is larger than the maximum value of the azimuthal angle over a revolution around the Earth.

Abstract: A method for transmitting digital data by a primary optical signal between a transmitter terminal and a receiver terminal, involves the following steps: determining a magnitude characterizing optical-wave degradation between the transmitter terminal and the receiver terminal, determining a number of transmission channels by a decreasing function of the magnitude characterizing optical-wave degradation, distributing the digital data over the transmission channels, modulating optical signals of different wavelengths using digital data distributed over the transmission channels, generating the primary optical signal by wavelength multiplexing of the optical signals, and sending a transmission configuration, including at least the number of transmission channels, from the transmitter terminal to the receiver terminal.

Abstract: A photonic radiofrequency signal cross-connect and frequency conversion device comprises: electronic/optical converters, for transferring radiofrequency input signals to optical carriers; optical combiners for grouping together in one and the same optical path several optical signals generated by the electronic/optical converters; electro-optical modulators for mixing the optical signals being propagated in a same optical path with a respective radiofrequency carrier; optical splitters for splitting the optical signals at the output of the modulators; optical combiners for grouping together the optical signals deriving from different optical paths; and optical/electronic converters, associated with these optical combiners. A space-borne telecommunications payload comprising such a photonic device is also provided.

Abstract: An inter-satellite communication device for satellites orbiting within a constellation of satellites comprises at least one optical terminal dedicated to intra-orbital plane communication links and at least one optical terminal dedicated to inter-orbital plane communication links, each optical terminal dedicated to intra-orbital plane communications configured to transmit and receive optical signals with an optical terminal of an identical satellite orbiting in the same orbital plane, each optical terminal dedicated to inter-orbital plane communications configured to transmit and receive optical signals with an optical terminal of an identical satellite in an orbital plane adjacent over the entirety of its orbit in its orbital plane and each optical terminal dedicated to inter-orbital plane communications having a field of regard such that the half-angle at the vertex of the latter is larger than the maximum value of the azimuthal angle over a revolution around the Earth.

Abstract: A distributed feeding device for antenna beamforming comprises a first distributed feeding circuit comprising P inputs and N outputs, for producing a signal on each of its outputs with a phase shift which is substantially constant between two adjacent outputs, at least one frequency multiplexer connected to at least one input of the said first circuit, a number N of frequency demultiplexers each connected, by their input, to an output of the first circuit and a second distributed feeding means comprising a plurality of inputs, each connected to an output of one of the frequency demultiplexers, and a plurality of outputs, the second distributed feeding means comprising at least one second distributed feeding circuit comprising Q inputs and M outputs, for producing a signal on each output with a phase shift which is substantially constant between two adjacent outputs, the integers P, N, Q and M being equal or distinct.

Abstract: A distributed feeding circuit for antenna beamforming array comprises a plurality N of inputs and a plurality N of outputs, wherein the said circuit is adapted for receiving, on at least one input, an electrical signal at a microwave frequency, modulated on at least one optical carrier, the circuit comprising at least one assembly of at least two optical dividers, two delay lines of length zero or substantially equal to a fraction of the wavelength of the signal at its microwave frequency and two means for combining two optical signals, the assembly being arranged and the delay lines being configured so that the theoretical transfer function of the circuit is an orthogonal matrix.

Abstract: A photonic radiofrequency signal cross-connect and frequency conversion device comprises: electronic/optical converters, for transferring radiofrequency input signals to optical carriers; optical combiners for grouping together in one and the same optical path several optical signals generated by the electronic/optical converters; electro-optical modulators for mixing the optical signals being propagated in a same optical path with a respective radiofrequency carrier; optical splitters for splitting the optical signals at the output of the modulators; optical combiners for grouping together the optical signals deriving from different optical paths; and optical/electronic converters, associated with these optical combiners. A space-borne telecommunications payload comprising such a photonic device is also provided.

Abstract: A method for transmitting digital data by a primary optical signal between a transmitter terminal and a receiver terminal, involves the following steps: determining a magnitude characterizing optical-wave degradation between the transmitter terminal and the receiver terminal, determining a number of transmission channels by a decreasing function of the magnitude characterizing optical-wave degradation, distributing the digital data over the transmission channels, modulating optical signals of different wavelengths using digital data distributed over the transmission channels, generating the primary optical signal by wavelength multiplexing of the optical signals, and sending a transmission configuration, including at least the number of transmission channels, from the transmitter terminal to the receiver terminal.

Abstract: A distributed feeding circuit for antenna beamforming array comprises a plurality N of inputs and a plurality N of outputs, wherein the said circuit is adapted for receiving, on at least one input, an electrical signal at a microwave frequency, modulated on at least one optical carrier, the circuit comprising at least one assembly of at least two optical dividers, two delay lines of length zero or substantially equal to a fraction of the wavelength of the signal at its microwave frequency and two means for combining two optical signals, the assembly being arranged and the delay lines being configured so that the theoretical transfer function of the circuit is an orthogonal matrix.

Abstract: A distributed feeding device for antenna beamforming comprises a first distributed feeding circuit comprising P inputs and N outputs, for producing a signal on each of its outputs with a phase shift which is substantially constant between two adjacent outputs, at least one frequency multiplexer connected to at least one input of the said first circuit, a number N of frequency demultiplexers each connected, by their input, to an output of the first circuit and a second distributed feeding means comprising a plurality of inputs, each connected to an output of one of the frequency demultiplexers, and a plurality of outputs, the second distributed feeding means comprising at least one second distributed feeding circuit comprising Q inputs and M outputs, for producing a signal on each output with a phase shift which is substantially constant between two adjacent outputs, the integers P, N, Q and M being equal or distinct.

Abstract: The invention relates to a system for conveying digital signals inside a space vehicle between a transmitter and a receiver. In the invention, the link between the transmitter and the receiver comprises a first portion made of optical fiber and a second portion in which infrared radiation propagates without guidance. A particular application lies in conveying remote control and telemetry signals within a satellite between a control module and a piece of equipment.

Abstract: The invention relates to a communications backbone interface between at least three members of a communications network for a space vehicle. In the invention, the interface combines various signals received at inlets, which signals may be analog, digital, and optical, coming from two members, and produces a multiplexed optical signal for delivery to a member of the vehicle, such as a piece of equipment. The invention also provides to a communications terminal interface, a communications network having such interfaces, and an optical fiber harness.

Abstract: The invention is related to a wavelength allocation scheme for a WDM (Wavelength Division Multiplex) equipment with a distribution of used optical channels that are arranged around a saturation channel in a way that the total spectrum of the optical channels is balanced independent from the number of equipped optical channels.

Abstract: To solve a problem of modularity favoring under-equipping and a problem of energy losses in an all-optical distribution frame for optical lines, a primary converter block includes a redundancy circuit which can emit an optical signal with a wavelength different from any of the other wavelengths broadcast by the other converter circuits of the primary block. In this case a star coupler responsible for frequency domain cross-connection of the signals preferably includes P+1 input channels for P output channels.