Abstract: A method (50) of acquiring images of a terrestrial region Z using a spacecraft (10) in non-geostationary orbit around the Earth (30), the spacecraft includes an observation instrument associated with a ground footprint of length L along the direction of travel, the method includes: a step (51) of observing a portion P1 of the terrestrial region Z, including a step of controlling the attitude of the spacecraft (10) during which the ground footprint is kept stationary during the entirety of the step of observing portion P1, and a step of acquiring an image of portion P1, a step (52) of modifying the pitch attitude of the spacecraft (10) so as to place the ground footprint over a portion P2 of the terrestrial region Z, and a step (53) of observing portion P2 of the terrestrial region.

Abstract: A computer assisted method for manufacturing a foldable paraboloid antenna includes election of a two-dimensional radial Origami pattern with triangular cells and election of a paraboloid surface. The Origami pattern is projected from the paraboloid surface focus onto the paraboloid surface to print the Origami pattern on the paraboloid surface, obtaining triangles with curved sides. A pattern with triangles with straight sides on the paraboloid surface is obtained by joining vertices of the projected curved-sided triangles. The method includes scaling and calculating centroids of the triangles, to reduce each triangle referenced on the corresponding centroid and to determine spacing, obtaining a mesh with segments and triangular cells delimited by the segments. The triangular cells have triangles of reflective rigid material. The mesh is flexible, so each segment width is at least the sum of the thicknesses of two adjacent rigid triangles, and periphery cells have a rounded outer edge.

Abstract: A method for estimating collision between a satellite in orbit and at least one piece of space debris having a time of closest approach to the satellite is disclosed including: obtaining the reference orbit of the satellite; determining an ephemeris of state transition data representative of the trajectory of the reference orbit; communicating the reference orbit and the ephemeris of state transition data to the satellite. The method includes the steps on board the satellite of: determining the true orbital position of the satellite; propagating the true orbit; calculating a probability of collision between the satellite and the piece of debris.

Abstract: A deployable assembly for antennae includes a structure having a reflective surface and n pairs of segments, each pair of segments corresponding to one side of a deployed polygonal shape. N hinge joints are between the two segments of a side. N hinged angular links are between every two adjacent sides. The structure is changeable from a stowed substantially cylindrical shape into a deployed substantially planar polygonal shape with n sides. A deployable boom is between two segments. The boom lays stowed between the two segments before deployment and ends in a feeder electromagnetically feeding the antenna and includes a clamping element for keeping the structure closed when stowed. The feeder acts as structural support element when stowed and electromagnetic feeder for the antenna when deployed. A cable network shapes the reflective surface, with corresponding cables held by tensor elements protruding from the back of the segments.

Abstract: A method and a receiver device for detecting the start of a frame of a satellite communication signal. A shaping filtering is applied directly after sampling of the signal, before a frequency correction is applied. During a first phase, an approximate frequency error and a candidate first sample for the start of the frame are estimated by performing several correlations respectively associated with different frequency hypotheses. The samples obtained after sampling or after shaping filtering are buffered during the execution of the first phase. Then, during a second phase, a final candidate sample for the start of the frame is determined from the memorised samples, using the approximate frequency error and the candidate first sample estimated during the first phase.

Abstract: A fiber composite laying method for producing a fiber composite scrim for forming a fiber composite component. The method includes supplying a reinforcement fiber band to a laying head, laying and compacting the supplied reinforcement fiber band on a laying surface at an average compaction pressure by a compaction roller, and detecting a local compaction pressure on the laid reinforcement fiber band by pressure sensors on the compaction roller.

Abstract: An optimisation method is presented for the transmission of data along any radio frequency link which can be split into distinct transmission blocks, an example being a beam hopping system. By reordering the packets to be transmitted, it is possible to send packets either at, or nearer to, their optimal modulation and encoding configuration. This will allow for a higher bit to symbol conversion for the majority of packets and hence more data bits can be sent for the same number of symbols.

Abstract: A terminal (100) for optical communication by laser signals including a matrix image sensor used as a tracking and acquisition detector (2). The matrix image sensor is used simultaneously to check that a portion of the laser signals received by the terminal are injected into an optical fibre (1). A spectral filter element (22) is associated with the matrix image sensor to allow such a combination of functions.

Abstract: A composite component system includes a base component with a first component fiber ply and a second component fiber ply and a repair insert with a first repair fiber ply and a second repair fiber ply. The base component is connected to the repair insert by an adhesive joint. The first component fiber ply has an interface surface connected to the interface surface of the first repair fiber ply by the adhesive joint. The second component fiber ply has an interface surface connected to the interface surface of the second repair fiber ply by the adhesive joint. The first component fiber ply has a fiber orientation corresponding substantially to a fiber orientation of the first repair fiber ply. The interface surface of the first repair fiber ply completely overlaps the interface surface of the first component fiber ply.

Abstract: A fuselage for an aircraft. The fuselage has a control element with an integrated engine outlet. The control element is integrated at a rear end of the fuselage, so that the control element terminates flush with an outer skin of the fuselage in a circumferential direction of the fuselage. An outer wall of the control element surrounds the engine outlet wherein the engine outlet is directed towards an open rear side of the control element. The control element is connected to the fuselage such that the control element jointly the engine outlet is pivotable about a rotation axis with respect to the fuselage. The rotation axis runs transversely to a longitudinal direction of the fuselage and the control element functions as a tailplane when pivoting about the rotation axis.

Abstract: An apparatus for releasing received command data includes a processor unit with a code generator, a cryptography module, and a comparison module. The code generator generates a transaction code. The apparatus has a transmitting unit which provides the transaction code via an unsecured data connection, a receiving unit which receives an external authentication code and command data via the unsecured data connection, and a memory unit which stores data of a predefined private key. Also disclosed is a transmission apparatus for command data. The transmission apparatus has a basic receiving unit which receives the transaction code, an input unit which receives the command data, a basic memory unit which stores the data of the predefined private key, a basic processor unit which has a basic cryptography module, and a basic transmitting unit which provides the external authentication code and the command data via the unsecured data connection.

Abstract: A system for monitoring the state of an unmanned aircraft includes a first communication unit, a second communication unit that can be integrated within the aircraft, a state transmission unit that can be integrated within the aircraft for transferring state data of the aircraft, a receiving unit integrated within the aircraft for receiving control commands, a computing unit assigned to the aircraft for validating the state of the aircraft, and an external control and monitoring unit connected to the computing unit. The computing unit executes a simulation model of the aircraft, which is based on numerical integration of a system of equations with a simulation state vector. The computing unit sends a warning signal to the control and monitoring unit on the occurrence of one or repeated instances of a model error correction term exceeding specified interval limits.

Abstract: A method of telecommunications includes the steps of receiving an encoded block having a plurality of values, dividing the received encoded block into a plurality of received segments, each received segment comprising at least two of the values, decoding each received segment by providing, for each received segment, a plurality of estimated encoded sequences, each estimated encoded sequence comprising at least two data units, merging estimated encoded sequences for consecutive segments to provide a plurality of candidate sequences, and selecting one of the plurality of candidate sequences by performing a closest fit calculation between the received encoded data block and each of the candidate sequences. The method is suitable for use in software-defined radios.

Abstract: A method for synchronizing wireless network nodes of a wireless communication network involves a base station of the wireless communication network to determine or obtain a maximum value for a frequency content per unit of time of an FMCW radio-frequency signal interfering with the wireless communication network, transmit a first synchronization frame containing a first synchronization sequence in a first wireless communication frequency bandwidth, and transmit a second synchronization frame simultaneously to the first synchronization frame, the second synchronization frame containing a second synchronization sequence in a second wireless communication frequency bandwidth that is spaced apart from the first wireless communication frequency bandwidth by a spectral distance larger or equal to the product of the determined maximum value for the frequency content per unit of time of the FMCW radio-frequency signal and duration of the first and second synchronization sequences.

Abstract: An interconnector plate for a fuel cell and a fuel cell system for an aircraft. For better extraction of the energy generated by the fuel cell, an interconnector plate can be attached by form fit to fixing studs of the fuel cell by retaining eyes. The interconnector plate may additionally be secured using glass solder. In preparation for a higher power density, a fuel cell can be produced in ceramic by 3D-printing and has an improved power density because of its helical shape.

Abstract: An elongate flexible waveguide section for radio frequency signals is provided, wherein the waveguide section is corrugated in the longitudinal direction, and the waveguide section is at least partially corrugated in a circumferential direction perpendicular to the longitudinal direction. Also provided is an apparatus for connecting a VHTS antenna system to a spacecraft.

Abstract: A system and method for secure cloud computing. The cloud based processing system comprises a user interface, allowing a user to enter and edit data, a proxy server, and a cloud based processing server. The user interface sends data entered by a user to the proxy server, which sends the encrypted data to the cloud based processing server. The proxy server receives editing commands from the user interface, and sends those commands to the cloud based processing server along with the encrypted data. The cloud based processing server receives the encrypted data and editing commands, applies the editing commands to the encrypted data, and sends the edited encrypted data back to the proxy server.

Abstract: A preprocessing technique for synthetic radar images. An embodiment of a method for preprocessing synthetic aperture radar images includes: receiving range-compressed radar data generated from raw radar image data on-board a satellite or an airborne vehicle; generating a preliminary SAR image by performing a pre-focusing on the range-compressed radar data; extracting image subsectors from the preliminary SAR image; transmitting the extracted image subsectors to an on-ground portion; reconstructing the range-compressed radar data pertaining to the extracted image subsectors; and making the range-compressed radar data pertaining to the extracted image subsectors available for a Nominal synthetic aperture radar processor, wherein the Nominal synthetic aperture radar processor is configured to generate a focused SAR image having a nominal value of image resolution that is higher than the resolution of the preliminary SAR image.

Abstract: An air direction arrangement for an aircraft. The air direction arrangement contains an inlet opening and an inlet channel connected thereto and which is at least partially surrounded by an outer wall. The inlet channel is configured to guide air to an engine of the aircraft. The outer wall contains at least one outlet channel and at least one outlet element. The outlet element is configured to selectively release or close the outlet channel for an air flow from the inlet channel into the environment of the aircraft. The air direction arrangement contains a heat exchanger in the outlet channel to discharge thermal energy to the air flow which is flowing from the inlet channel into the environment of the aircraft.

Abstract: A method (50) for orbit control of a satellite (10) in Earth orbit and for desaturation of an angular momentum storage device of the satellite, the satellite (10) including an articulated arm (21) suitable for moving a propulsion unit (31) within a motion volume included in a half-space delimited by an orbital plane when the satellite is in a mission attitude, the method (50) including a single-arm control mode using only the propulsion unit (31) carried by the articulated arm (21), the single-arm control mode using a maneuvering plan including only thrust maneuvers to be executed when the satellite (10) is located within an angular range of at most 180° centered on a target node in the orbit of the satellite (10), including two thrust maneuvers to be performed respectively upstream and downstream of the target node.