Abstract: A telecommunication system has a space segment which includes a satellite carrying a multibeam telecommunications payload and a terrestrial segment comprising gateways for access to a terrestrial network. There is one gateway within a terrestrial coverage of each beam or of a group of beams. User terminals communicate with the payload of the satellite. The payload has, on a forward path from any gateway to any user terminal, a frame by frame routing unit for messages transmitted in time division multiplex. On a return path from a user terminal to a gateway the payload has a routing unit operating within each group of carriers belonging to a given beam.

Abstract: A satellite has a platform of elongated shape in a direction parallel to a roll axis of the satellite. A deployable arm is pivotally carried by a longitudinally extending face of the platform. A solar generator is carried at the end of the arm by a first motor for aiming the generator through a range of 360° about a pitch axis orthogonal to the direction of elongation of the platform. A second motor rotates the solar generator through a limited angular range about an axis that is orthogonal to the pitch axis and parallel to the plane of the generator. The arm, when deployed, moves the solar generator away from on a stored position in contact with the platform in a direction of a yaw axis.

Abstract: A method is disclosed for controlling the attitude of a satellite by controlling the speed of the gimbals of CMGs in a cluster of CMGs, the CMG having respective wheels mounted on gimbals that are mounted on a satellite platform to rotate about different orientation axes. From starting conditions and end conditions relating to attitude and angular speed and time, a cluster configuration is determined that is remote from any singular configuration such that exchanging angular momentum between the cluster of CMGs and the satellite during a given length of time will give rise to the desired attitude maneuver. The orientation of each gimbal is changed in simultaneous and independent manner into its reference orientation by using an angular position reference, applied in an open loop in the local servo-control of the angular positions of the gimbals.

Abstract: Thermal link device for use between an end surface of a cold finger of a cryogenic machine, at cryogenic temperature when in use, and a load, comprising:a plate confronting said end surface, for connection with the load, mechanically separate from the end surface and defining a condensation and vaporization gap with said end surface,a capillary pumping element in said gap,a flexible wall defining an enclosure accommodating said gap and surrounding at least said end surface and a portion of a cold finger which is close to said end surface, andgas means in said enclosure, said gas means including at least one gas having a condensation temperature selected responsive to a cryogenic temperature to be given to the load.

Abstract: The CCD device is suitable for use in a lidar. It has an image zone constituted by a matrix of M lines and N columns of photosensitive sites for receiving a light signal and generating charges, a first memory zone constituted by a matrix of P lines and N columns of non-photosensitive sites, a read-out register having a single line of N sites, and a second memory zone having P lines of N sites, apt to receive in parallel charges contained in the N sites of the read-out register. The first memory zone has a first line of sites apt to receive and to sum charges generated in a respective column of the image zone at the end of each of successive acquisition periods. The second memory zone stores and transfers charges to N sites of a same line of the image zone or the first memory zone whereby accumulating, in each line of the first memory zone, charges accumulated during an observation period and resulting from a plurality of successive summations.

Abstract: An earth orbiting satellite is enabled to assume a "survival mode" of operation in which its x axis is aligned with the sun by observing characteristics of the movement of the frame of the satellite (e.g. its x axis) relative to the sun and performing calculations based on those operations. A more accurate result is achieved if a deliberate offset is introduced between the mean direction of the x axis and the sun's direction. The control arrangement for positioning the x axis with this offset is preferably adaptive, resulting in control of the satellite's thrusters so as to produce oscillation of the x axis in a way which allows suitable measurements to be taken.

Abstract: A rotary actuator includes a bar made of shape memory alloy having ends provided with thermally insulating interface elements for interfacing with elements that are to be rotated relative to each other. An electric heater surrounds the bar and is apt to heat it above its transition temperature to the austenitic domain. The actuator is suitable for deploying or rotating solar panels.

Abstract: A microwave source has an amplifying transistor capable of operating at microwave frequencies and a frequency selection circuit. The circuit has a whispering mode dielectric resonator and a feedback loop having a first microstrip line connected by an impedance adaptation circuit to a gate of said transistor and a second microstrip line connected by an impedance adaptation circuit to a drain of said transistor. The dielectric resonator is located between the first line and the second line for magnetic field coupling therewith.

Abstract: The apparatus has n non aligned antennas, where n is at least for receiving radio signals from a plurality of OPS satellites. Radio frequency signals received by the various antennas are processed for measuring their phase differences, and for computing attitude on the basis of said phase differences. The measurement and computing system is repeatedly calibrated on the basis of measurements performed by a star sensor during periods when it provides usable data.

Abstract: The attitude of a satellite placed on a non-heliosynchronous earth orbit in a plane that is inclined relative to the equatorial plane of the earth is controlled for efficient use of solar panels and radiators. The satellite has a structure, solar panels apt to be rotated with respect to the structure rotation and two opposed radiators each fixed on one of two opposed faces of the satellite structure which are orthogonal to the rotation axis. One of the radiators has greater emissivity than the other. A yaw axis bound to the structure satellite and orthogonal to rotation axis is aimed towards the earth. The solar panels of the satellite are maintained in an optimum orientation relative to the sun by rotating them. At least during periods of each year when an angle .beta.

Abstract: For controlling the attitude of the body of an earth satellite placed on a low orbit, values of components of the geomagnetic field of the earth are measured along three axes of a frame of reference bound to the body. The values are derivated with respect to time, and multiplied by a gain. Currents responsive to the multiplicated derivatives are passed through magnetic torquers located along the three axes of the body to create magnetic torques that bias the body to a fixed angular position relative to the field lines of the geomagnetic field. Such steps are continuously carried out during eclipse periods. Out of eclipse periods, the pitch of the body is controlled by modifying an internal momentum in response to a signal provided by a solar sensor, so as to maintain solar generators carried by the body of the satellite oriented towards the Sun.

Abstract: The telescope includes at least one primary concave mirror (MI) for receiving an incoming image and relay optics for enlarging the image reflected by the primary mirror. The relay optics comprise a secondary mirror (M2) and a tertiary mirror (M3), each having a central aperture (12, 13) and each being positioned coaxially with the primary mirror (M1). The secondary mirror (M2) receives the image reflected by the primary mirror (M1) through the central aperture (13) of the tertiary mirror (M3). The tertiary mirror (M3), positioned close to the focal plane of the primary mirror (M1), receives the image reflected by the secondary mirror (M2) and reflects that image through the central aperture of the secondary mirror (M2).

Abstract: A three axis stabilized geostationary satellite comprises a structure having walls that face North and South when the satellite is on station and carrying at a storage battery of large capacity. The storage battery is constituted by cells mounted on a chassis having a base plate oriented North-South and mechanically secured to sides that face North and South when the satellite is on station. The sides carry thermal radiators that are thermally connected to each other and to the cells. Typically sides are in alignment with North and South faces of the structure and extend away from the Earth.

Abstract: The chip is fixed to a substrate by its lower face. At least one wire-bonding adaptor in the form of a board is used, the upper face of which has first bonding pads along at least one first edge and second bonding pads along at least one second edge, and including electrical connections between the first and second bonding pads. The wire-bonding adaptor is adhesively bonded by its lower face to the upper face of the chip so that the said first edge is adjacent to a row of output pads located elsewhere than on the periphery of the upper face of the chip and so that the said second edge is adjacent to the periphery of the chip. Bonding wires are bonded, on the one hand, between the output pads of the said row and the first bonding pads and, on the other hand, between the second bonding pads and conducting pads on the substrate.

Abstract: The device can be used on an aircraft or spacecraft. It comprises a laser for emitting short light pulses, a channel for receiving the backscattered light flux and an optical conical scanner means making it possible to orient a direction common to laser emission and to reception via the channel along successive generatrices of a cone. The scanner has a mirror rotated about a scanning axis for deflecting an optical path common to a receiving detector and to the laser along successive directions distributed at regular angular intervals around the scanning axis and several stationary reflectors distributed at the regular intervals. The reflectors are successively inserted on the common optical path by the rotating mirror. The stationary reflectors correspond to different probing orientations along the cone. The rotating mirror has a size very much less than that of the beam entering and exiting the device.

Abstract: The terrestrial sensor device is suitable for use on a satellite or spacecraft. It has a lens for forming an image of the Earth in a focal plane, and a sensor placed in the focal plane. The sensor is constituted by a two-dimensional array of pyroelectric detectors. The device also includes an actuator for oscillating the array in the focal plane, orthogonally to the optical axis of the image-formation lens, at a determined frequency and with an amplitude at least equal to the distribution spacing of the detectors and a processing circuit for acquisition of the output signals of the detectors at the oscillation frequency and for comparison of the output signals with a threshold.

Abstract: The multi-chip module comprises a co-fired substrate, and, on at least ont face of the substrate, a set of superimposed ceramic insulating layers, fired at a temperature substantially smaller than the firing temperature of the substrate. Conducting interconnection lines are formed in thick layers deposited between said ceramic insulating layers. Electronic components are mounted at the surface of the set of ceramic layers.

Abstract: The cooling device for cooling a travelling-wave tube is deigned to be mounted on board a geostationary telecommunications satellite. The collector of the tube is thermally insulated from the remainder of the tube and it is thermally connected to a radiator by means of a link part passing through a north or a south panel of the satellite structure and insulated from the panel.

Abstract: A pluggable electrical connection device comprises at least one pin-shaped male element of electrically conductive material and at least one female element. The female element is a metal coil spring having at least four turns sufficiently spaced apart to receive the male element between two mutually adjacent turns. The coil spring may have end portions which are bent to constitute tabs parallel to an axis of said coil spring and soldered to said support. It may also be locked between two elongated holes formed in two opposed sides of a cage and connected to a base circuit fast with said cage by pin.

Abstract: A memory component has a rectangular semiconductor substrate containing active memory circuits and output terminals on a major surface thereof. An insulating layer on the major surface receives a plurality of metal connection leads, connecting the output terminals to connection pads located on the major surface along only one of longer sides of the substrate. A plurality of additional pads are distributed between the connecting pads and are devoid of connection leads. A memory module comprising several stacked memory components is also described, which uses the additional pads as relays.