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: 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: 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 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: The present invention relates to an amplifier system for satellites, in particular for radio-frequency amplifier systems incorporating travelling wave tube amplifiers and used in space repeaters. The amplifier system (1) includes two amplifier modules (A1, A2) each having an input and an output, a signal divider (D) having an input, a first output, and a second output, a signal combiner (C) having a first input, a second input and an output. The first output of the divider (D) is connected to the input of the first amplifier module (A1) via a connection length Le1. The second output of the divider (D) is connected to the input of the second amplifier module (A2) via a connection length Le2. The output of the first amplifier module (A1) is connected to the first input of the combiner (C) via a connection length Ls1. The output of the second amplifier module (A2) is connected to the second input of the combiner (C) via a connection length Ls2.

Abstract: The present invention relates to an amplifier system for satellites, in particular for radio-frequency amplifier systems incorporating travelling wave tube amplifiers and used in space repeaters. The amplifier system (1) includes two amplifier modules (A1, A2) each having an input and an output, a signal divider (D) having an input, a first output, and a second output, a signal combiner (C) having a first input, a second input and an output. The first output of the divider (D) is connected to the input of the first amplifier module (A1) via a connection length Le1. The second output of the divider (D) is connected to the input of the second amplifier module (A2) via a connection length Le2. The output of the first amplifier module (A1) is connected to the first input of the combiner (C) via a connection length Ls1. The output of the second amplifier module (A2) is connected to the second input of the combiner (C) via a connection length Ls2.

Abstract: A satellite for a satellite telecommunication system transmits signals at different powers on the downlink connection. The powers are chosen to limit the relative dynamic range of signals received on the downlink connection. The relative dynamic range of signals received on the downlink connection is advantageously less than 5 dB and preferably less than 2 dB. A digital processor circuit is used, together with an analog-digital converter, a circuit taking the fast Fourier transform of the converted signals, a circuit for monitoring the gain of the signals, a circuit for switching the signals to at least two amplifier subsystems each including an inverse fast Fourier transform circuit, a digital-analog converter and a power amplifier.