Abstract: A relay platform for communicating telemetry data from one or more moving observation satellite(s) to the ground is provided. The relay platform for communicating from a space observation system, installed on board an aircraft moving above the clouds, comprises a first reception interface for demodulating telemetry data from at least one moving observation satellite, a second transmission interface for modulating and transmitting the data received to at least one destination ground station. The relay platform comprises a first descending two-level decryption/encryption chain for the telemetry data returned from at least one moving observation satellite(s) to the destination ground station(s).

Abstract: A relay platform for communicating telemetry data from one or more moving observation satellite(s) to the ground is provided. The relay platform for communicating from a space observation system, installed on board an aircraft moving above the clouds, comprises a first reception interface for demodulating telemetry data from at least one moving observation satellite, a second transmission interface for modulating and transmitting the data received to at least one destination ground station. The relay platform comprises a first descending two-level decryption/encryption chain for the telemetry data returned from at least one moving observation satellite(s) to the destination ground station(s).

Abstract: A system for space-based imaging in three dimensions includes at least two satellites in a geocentric orbit in a same orbital plane, a satellite being equipped with equipment for optical imaging in two dimensions and a system for transmitting to the ground images in two dimensions; at least one data receiving station on the ground, connected to a communications network; at least one center for processing the images received in two dimensions from the satellites in order to create resulting images in three dimensions and to broadcast the resulting images in three dimensions, the processing center being connected to the communications network; and, a system for controlling the satellites such that a geographical area of the Earth of which images are to be taken is seen under an angle of incidence with respect to a nadir greater than a minimum threshold and/or less than a maximum threshold.

Abstract: A system of geographical location of at least one radio signal transmitter located on the Earth's surface including: a set of satellites equipped with receiving antennas adapted for receiving said signals, forming a main extended interferometry device; an intersatellite relative metrology device for determining the relative positions of said satellites to one another, including at least one dedicated sensor for each satellite, and intersatellite communication means; a device for dating said received signals from said determining of the relative positions of said satellites to one another, issued by said intersatellite relative metrology device; a secondary interferometry device including at least one set of at least three antennas of a satellite; a ground base station; a device for transmitting measurements acquired on the satellites to the ground base station; and means of determining an absolute position of at least one of the satellites.

Abstract: A system of geographical location of at least one radio signal transmitter located on the Earth's surface including: a set of satellites equipped with receiving antennas adapted for receiving said signals, forming a main extended interferometry device; an intersatellite relative metrology device for determining the relative positions of said satellites to one another, including at least one dedicated sensor for each satellite, and intersatellite communication means; a device for dating said received signals from said determining of the relative positions of said satellites to one another, issued by said intersatellite relative metrology device; a secondary interferometry device including at least one set of at least three antennas of a satellite; a ground base station; a device for transmitting measurements acquired on the satellites to the ground base station; and means of determining an absolute position of at least one of the satellites.

Abstract: The invention provides a method of determining the location of one or more terrestrial transmitters by measuring the electromagnetic field vector at a plurality of instants from an antenna of a satellite. The propagation direction of the electromagnetic field and the location of the transmitter are determined on the basis of the measured vectors. The invention also provides methods of locating a terrestrial transmitter by using a plurality of optionally geostationary satellites. The invention also provides a satellite comprising an antenna and means for implementing such methods.

Abstract: The invention provides a method of determining the location of one or more terrestrial transmitters by measuring the electromagnetic field vector at a plurality of instants from an antenna of a satellite. The propagation direction of the electromagnetic field and the location of the transmitter are determined on the basis of the measured vectors. The invention also provides methods of locating a terrestrial transmitter by using a plurality of optionally geostationary satellites. The invention also provides a satellite comprising an antenna and means for implementing such methods.

Abstract: The invention relates to a method of locating a jammer (14) of a satellite telecommunications system (10). To locate the jammer, at least two of the following three measurements are performed: a measurement of the difference between the instant of arrival at the telecommunications satellite and at a detection satellite (16) of signals transmitted at the same time by the jammer (14), the detection satellite being used solely for detection purposes; a measurement of the difference between the frequencies received by the telecommunications satellite and by the detection satellite, for a signal transmitted by the jammer; and an interferometric measurement of the angle between a direction associated with the detection satellite and the straight line between said satellite and the jammer (14).