Abstract: A receiver for radiofrequency signals designed to be installed on board a satellite comprises: a device for frequency controlling the receiver allowing the reception frequency of the receiver to be adjusted based on a frequency command; and a filtering assembly of the bandpass filter type having a passband, referred to as passband of the filtering assembly, having an adjustable passband width able to take a set of values, the filtering assembly allowing the bandwidth of a first signal representative of the input signal of the receiver to be limited to the passband of the filtering assembly; adjustment means allowing the width of the passband of the filtering assembly to be adjusted using a filtering passband control; power acquisition means allowing a measurement of the power of the first signal to be delivered at the output of the filtering assembly.

Abstract: A receiver for radiofrequency signals designed to be installed on board a satellite comprises: a device for frequency controlling the receiver allowing the reception frequency of the receiver to be adjusted based on a frequency command; and a filtering assembly of the bandpass filter type having a passband, referred to as passband of the filtering assembly, having an adjustable passband width able to take a set of values, the filtering assembly allowing the bandwidth of a first signal representative of the input signal of the receiver to be limited to the passband of the filtering assembly; adjustment means allowing the width of the passband of the filtering assembly to be adjusted using a filtering passband control; power acquisition means allowing a measurement of the power of the first signal to be delivered at the output of the filtering assembly.

Abstract: Device for controlling a frequency F of a TTC satellite link transmitter and/or receiver on the basis of a frequency command whose value is taken in a predetermined frequency plan composed of several frequency notches distributed in a discontinuous manner in a given frequency band, said device including a quartz oscillator delivering a reference frequency FOCXO, a synthesized local oscillator delivering said frequency F on the basis of said reference frequency FOCXO according to a relation F = F OCXO ? N R where N and R are programmable divider coefficients, and a digital integrated circuit which implements a conversion table mapping each frequency notch of said predetermined frequency plan to a set of binary addresses distributed in a contiguous manner addressing the values of said coefficients N and R in the form of binary words allowing the synthesized local oscillator to generate said frequency F whose value is equal to that of said frequency command.

Abstract: The invention relates to a telemetry, control, and ranging link of a satellite; it proposes using spread spectrum transmission for the up link, i.e. for commanding the satellite and for the ranging up signal. It proposes using subcarrier modulation for the down link, i.e. for telemetry and for the ranging down signal. This makes it possible for the up link to withstand interference and to provide co-localization; on the down link, the use of subcarrier modulation makes it possible to continue using existing equipment and known solutions.

Abstract: The subject of the present invention is a frequency and phase modulation remote control receiver for a geostationary satellite which is lighter and less expensive than the customary receivers, while not degrading the passband of the telecommunication equipment for its payload, and it is characterized in that it comprises a heterodyne amplifier analog input and filtering circuit (28) followed by a digital processing circuit (49) configurable as an FM demodulation device or as a PM demodulation device, the analog input circuit being common to both modes of demodulation.

Abstract: The invention concerns a satellite having at least two antennas (3, 5) whose radiation patterns overlap, at least in part and means (45; 47, 49, 51) for receiving the sum of the signals from the various antennas. To limit multipath problems when summing signals from the antennas, the invention proposes that the receiver means include means for demodulating a spread spectrum signal and that the absolute difference between the respective transmission times of signals transmitted to the receiver means via two antennas is greater than one chip of the spread spectrum modulation. Application to a satellite TTC (telemetry, tracking and command) link.

Abstract: The invention relates to the command link of a satellite, also referred to as the telemetry, tracking and control link. Depending on the bit rate needed for the link, the invention proposes using either direct modulation of a carrier to transmit at high bit rates or subcarrier modulation of the carrier to transmit at low bit rates. The invention also proposes a receiver and a transmitter for receiving and transmitting on the command link.