Abstract:
A process of encoding information data in a sequence of bursts ( . . . , Bi-2, Bi-1 Bi, Bi+1, . . . ), each burst comprising a block of information symbols and a block of redundancy symbols. The block of redundancy symbols (R,) of the current burst (B,) of the sequence is generated by calculating a sum of a series of coding values relating to a series of bursts (Bi-2, Bi-1), each coding value of the series of coding values being obtained by a respective coding function applied to the block of information symbols of the corresponding burst of the series of bursts.
Abstract:
The positioning receiver according to the invention comprises means for storing configuration information and information on its reception conditions, which is processed in order to calculate a current and/or predicted precision of the positioning calculation. Advantageously, at least some of this information is integrated into a variation model of a Kalman filter integrated into the receiver. The invention notably allows a more rapid convergence on a reference precision in a mono-frequency operating mode and transitions between a mono-frequency and bi-frequency mode to be smoothed. Advantageously, the precision information is delivered graphically or in numerical form to the user.
Abstract:
In the field of active phase-control antennas, a method is provided for calibrating the phase center of an active antenna including a plurality of sub-elements able to receive a useful signal emitted by a satellite, the calibration being defined as a function of the reception characteristics of a reference signal at the level of each sub-element, the reference signal being emitted by the same satellite on a frequency band substantially equal to the frequency band of the useful signal and whose theoretical reception characteristics are known.
Abstract:
A telecommunications satellite stabilized on three axes includes a set of dissipative equipment constituting a payload of the satellite. The satellite includes support data transmission antennas and is substantially parallelepipedal in shape with the panels forming two opposite faces, east and west faces. The panels form two additional opposite faces, north and south faces, and include radiator surfaces on their external faces. The radiator surfaces are configured to cool the electronic equipment of the satellite. The equipment installed on the north and south panels dissipate thermal power corresponding to less than 25% of the total dissipated power.
Abstract:
A method is provided of dynamic allocation of shared resources in a communication network, consisting in defining, in a time-frequency plan, a superframe of a given duration ΔT and a given spectral width Δf, made up of one or more frames, each defining a regular time-frequency grid, of which one square, referred to as a time-frequency unit, constitutes the smallest time and frequency interval allocable to a user of said network within said frame, said method consisting in reserving, on each carrier frequency of a frame, at least one block of a number K, greater than or equal to 1, of time-frequency units which can be dynamically allocated to a user for communication or for synchronization.
Abstract:
There is disclosed a computer implemented method for processing the signal emitted by a distress beacon, the signal being received by several satellites and forwarded to at least one ground station, the method comprising the steps consisting in determining a set of hypothetical positions of the beacon, and for at least one of the hypothetical positions, for each satellite, offsetting the signal received and forwarded as a function of the hypothetical position; summing the offset signals; and evaluating the validity of the sum of the offset signals as a function of the presence of a predefined characteristic in the sum. Developments describe aspects such as the temporal and/or frequency offsetting, the construction of a digital replica of the signal transmitted by the beacon, and as the minimizing of the weighted residues of the offsets. System aspects are described, including the calibration of an active antenna or an array of antennas.
Abstract:
A hyperfrequency interconnection device between two components is provided, each component comprising an upper face and a signal line arranged on the upper face, the planes containing the upper faces of the components being separated by a distance known as the height difference. The hyperfrequency interconnection device comprises a substrate comprising a lower face and an upper face defined by a first axis and a second axis perpendicular to the first axis, a signal line arranged on the lower face of the substrate, a projection of the signal line into the plane of the upper face forming the first axis, at least two contact pads capable of electrically connecting the signal line of the device to the signal line of the components. The upper face of the substrate is corrugated along the second axis, capable of conferring on the substrate flexibility along the first axis.
Abstract:
Disclosed is an optical time-stamping device, including an optical instrument with a retina having a field of view and being able to produce on the retina images of the field of view, and a high accuracy reference clock signal receive. The time-stamping device also includes: a lighting source at a distance from the retina of an optical instrument, and configured to emit a light signal in the direction of the retina of an optical instrument and in the field of view of an optical instrument, and a control unit connected to the reference clock signal receiver by a first connection and to the lighting source by a second connection, and configured for controlling the lighting source for emitting a light signal in a synchronized way with the reference clock signal. An associated image sensing system and optical time-stamping method are also disclosed.
Abstract:
A cooling method for cooling a device connected to a cryogenic tank via a main admission duct for feeding the device with cryogenic fluid once the device is cooled. In contrast, during cooling, a cryogenic fluid is introduced into the device via a cooling admission duct that is different from the main admission duct and that presents a flow section that is narrower than the flow section of the main admission duct.
Abstract:
A bandpass filter for microwave-frequency wave which is frequency tunable, comprises at least one resonator. Each resonator comprises a cavity having a conducting wall substantially cylindrical in relation to an axis Z, and at least one dielectric element disposed inside the cavity. The resonator resonates on two perpendicular polarizations having respectively distributions of the electromagnetic field in the cavity that are deduced from one another by a rotation of 90° and according to one and the same frequency. The wall of the cavity comprises an insert section facing the element having a different shape from a section not situated facing the element. The insert section and the element are able to perform a rotation with respect to one another in relation to the axis Z so as to define at least a first and a second relative position differing by an angle substantially equal to 45° to within 20°.