Abstract: A method of encoding fixed length data bit strings includes receiving and sequentially encoding a sequence of data bit strings. For a data bit string immediately following a preceding data bit string, this includes obtaining a reference bit string, and a mask bit string and a tracking bit string as present at the end of a previous encoding of the preceding data bit string, identifying bits that differ form corresponding bits in the reference bit string, determining, as unpredictable bits, all those bits in the data bit string that are indicated as not predictable by the mask bit string and are not in bit positions indicated by the tracking bit string, generating a sequence of position indicators, generating an encoded data packet that includes representations of values of the unpredictable bits and the sequence of positon indicators, and periodically updating the mask bit string and the tracking bit string.

Abstract: A directional coupler (100) comprises two hollow bodies (200, 201) forming two waveguide portions. Each hollow body has an open end arranged at a first side (10) of the hollow body and another open end arranged at a second side (20) of the hollow body opposite to the first side in a longitudinal direction (30) of the hollow body. The hollow body has a first cross section perpendicular to the longitudinal direction. A second cross section along the longitudinal direction defines a first plane of propagation of the electric field. The two waveguide portions have a common wall along the longitudinal direction (30) forming a septum (400) between the two waveguide portions on a second plane orthogonal to the first plane. The septum has an aperture (410) for coupling the two waveguide portions. The aperture has a shape comprising a part (420) slanted with respect to the longitudinal direction.

Abstract: The present disclosure relates to a filter for filtering wavelengths of an electromagnetic signal to provide a filtered signal. The filter includes: at least one commensurate-line structure (CLS); and, at least one stub-modified commensurate-line structure (SMCLS) arranged to provide a corresponding at least one transmission zero in the filtered signal.

Abstract: A method of controlling transmission of signals in a group of beams emitted by a satellite, wherein each beam has an associated area of coverage, includes adjusting an allocation of a channel resource by re-distributing portions of the channel resource among the beams in the group of beams in accordance with respective capacity demands for the areas of coverage of the beams in the group. The method further includes obtaining, for each of the areas of coverage, an indication of a signal quality from a terminal in the respective area of coverage for the adjusted allocation of the channel resource, and applying a co-channel interference mitigating technique to the group of beams in accordance with the obtained indications of the signal quality. The application further relates to an apparatus for performing such method.

Abstract: An apparatus and method are described for processing a global navigation satellite system (GNSS) signal, the GNSS comprising multiple satellites, wherein each satellite transmits a respective navigation signal containing a spreading code. The method comprises receiving an incoming signal at a receiver, wherein the incoming signal may contain navigation signals from one or more satellites; encrypting the incoming signal at the receiver using a homomorphic encryption scheme to form an encrypted signal; and transmitting the encrypted signal from the receiver to a remote server.

Abstract: A bi-state driver circuit for switching an output terminal between a first predetermined voltage level and a high impedance state, which involves a first string of transistors connected between the output terminal and the first predetermined voltage level at least a first transistor arranged closer to the first predetermined voltage level, a second transistor arranged closer to the output terminal, a voltage divider circuit connected between the output terminal and a voltage level of a control signal attaining voltage levels between the first predetermined voltage level and a second predetermined voltage level, including at least one intermediate node having an intermediate voltage level between a voltage level of the output terminal and the voltage level of the control signal, and a second string of transistors connected between the intermediate node of the voltage divider circuit and the second predetermined voltage level, and including at least a third transistor.

Abstract: A directional coupler (100) comprises two hollow bodies (200, 201) forming two waveguide portions. Each hollow body has an open end arranged at a first side (10) of the hollow body and another open end arranged at a second side (20) of the hollow body in opposite to the first side in a longitudinal direction (30) of the hollow body. The hollow body has a first cross section perpendicular to the longitudinal direction. A second cross section along the longitudinal direction defines a first plane of propagation of the electric field. The two waveguide portions have a common wall along the longitudinal direction (30) forming a septum (400) between the two waveguide portions on a second plane orthogonal to the first plane. The septum has an aperture (410) for coupling the two waveguide portions. The aperture has a shape comprising a part (420) slanted with respect to the longitudinal direction.

Abstract: A transceiver for imparting a voltage signal on a differential signaling bus, involving an output terminal and a string of one or more transistors connected between the output terminal and a predetermined voltage level. The transceiver can be switched between an active state in which the predetermined voltage level is applied to the output terminal, and an inactive state in which the predetermined voltage level is not applied to the output terminal. Methods for the transceiver can involve a detection step of detecting a first quantity depending on a current flowing through a first transistor in the string of transistors, a failure determination step of determining whether the detected first quantity satisfies one or more error conditions, and a control step of switching the transceiver to the inactive state if the detected first quantity is determined to satisfy at least one of the one or more error conditions.

Abstract: A method and apparatus are provided for determining a schedule for a contact between a ground segment and a space segment. The ground segment comprises multiple ground stations, each ground station having one or more antennas, such that the overall number of ground station antennas in the ground segment is (Nant), and the space segment comprises a constellation of satellites in orbit, in which the number of satellites is (Nsat). The method comprises selecting a subset of no more than Nant satellites from the Nsat satellites for contact at a given epoch with the ground segment; and allocating each of the selected Nant satellites to the Nant antennas in a one-to-one relationship at the given epoch. The selecting of the subset of no more than Nant satellites from the Nsat satellites comprises determining a subset of the Nant satellites that has maximum spatial diversity.

Abstract: A microwave branching switch for selectively interconnecting terminals of a plurality of microwave transmission lines, involving microwave transmission lines with a terminal; a housing in which the terminals are arranged; a switching portion with a junction portion for selectively interconnecting terminals of the microwave transmission lines through selective interconnection. The switching portion is switchable between a first position and a second position; wherein the switching portion with the junction portion is dimensioned and positioned inside the housing in dependence of an arrangement of the microwave transmission lines such that the junction portion interconnects a first group of terminals when the switching portion is in the first position and interconnects a second group of terminals when the switching portion is in the second position. The first and second groups of terminals differ in at least one terminal and the first group of terminals involves at least three terminals.

Abstract: The present invention relates to a method of manufacturing a component 1 by additive manufacturing. The method comprises providing a work surface 2 on which the component 1 is to be manufactured, and providing at least one deposition material 3 from which the component 1 is to be composed. The deposition material, typically in the form of wire, is advanced to a localized deposition area 4 where it is added to the component 1 being manufactured. The method further comprises focusing at least one light beam 5 of incoherent light emitted from at least one heating source 6 in the deposition area 4 so that the deposition material 3 is deposited for building up the component 1. At least one light focusing mirror 7 and/or lens 11 is used to focus the incoherent light in the deposition area 4. The invention further relates to the use of such a method in space, such as on a space station, on a space craft or on parabolic flights for testing.

Abstract: A method of performing radio occultation for inferring physical properties of a portion of atmosphere includes receiving, at a receiver, a first signal from a satellite at a first timing; receiving, at the receiver, a second signal from the satellite at a second timing different from the first timing; correlating the first signal with the second signal; and determining a first quantity indicative of a path delay between the first signal and the second signal resulting from at least one of the first signal and the second signal having passed through the portion of atmosphere between transmission by the satellite and reception at the receiver, based on a result of the correlation. The application further relates to a system for performing radio occultation for inferring physical properties of a portion of atmosphere.

Abstract: Reconfigurable RF front-end circuit for a multi-beam array fed reflector antenna system having a first plurality of NB input beam signals and a second plurality of NE radiating elements (RE), and method of operating such a front-end circuit. The front-end circuit comprises a reconfigurable beam forming network (LLRBFN), having a set of NB input ports and distributing each input port signal to a plurality of NA output ports with phase and amplitude control, a plurality of NA high power amplifiers (HPA) connected to the plurality of NA output ports of the reconfigurable beam forming network (LLRBFN) and an output network (ONET, OSN), arranged for recombining signals output by the high power amplifiers (HPA) and feeding the recombined signals to the second plurality of NE radiating elements (RE). The high power amplifiers (HPA) are variable bias high power amplifiers (VB-HPA).

Abstract: A fluidic filter for filtering a fluid includes a filter housing having an inlet part, an outlet part and a housing part, and a filter element having an inlet side and an outlet side. The filter element is housed inside the housing part of the filter housing and includes a first flow passage that extends along a longitudinal direction of the filter element and is connected to the outlet part, and a plurality of ridges extending along the longitudinal direction. A plurality of second flow passages respectively are formed between ridges and an inner surface of the housing part, allowing the fluid to flow from the inlet side of the filter element along the longitudinal direction. At least a portion of the plurality of ridges facing the second flow passages is permeable to the fluid so as to allow passage of the fluid from the second flow passages to the first flow passage.

Abstract: The present invention relates to a method of manufacturing a ceramic article (3) from a metal or metal matrix composite preform (1) provided by 3D-printing or by 3D-weaving. The preform (1) is placed in a heating chamber (2), and a predetermined time-temperature profile is applied in order to controllably react the preform (1) with a gas introduced into the heating chamber (2). The metal, the gas and the time-temperature profile are chosen so as to induce a metal-gas reaction resulting in at least a part of the preform (1) transforming into a ceramic. Preferred embodiments of the invention comprises a first oxidation stage involving a metal-gas reaction in order to form a supporting oxide layer (5) at the surface of the metal, followed by a second stage in which the heating chamber (2) is heated to a temperature above the melting point of the metal to increase the kinetics of the chemical reaction. The invention also relates to a number of advantageous uses of a ceramic article manufactured as described.

Abstract: A, method and apparatus for wirelessly transmitting data to a plurality of terminals in each of a plurality of beams through a plurality of transmit feeds includes selecting, for each beam, two or more terminals among the plurality of terminals in the beam as a subgroup of terminals, on the basis of channel state information of the plurality of terminals; determining, for each beam, equivalent channel state information representing the subgroup of terminals in the beam on the basis of the channel state information of the terminals of at least one of the plural subgroups of terminals; and determining a set of weight coefficients that relate the plurality of transmit feeds to a plurality of signals that are intended for transmission in the plurality of beams on the basis of the equivalent channel state information representing the plural subgroups of terminals.

Abstract: The present invention relates to a system for contactless induction of high-frequency vibrations in a volume of molten metal during the manufacturing of a metal component or a metal matrix composite component. The system includes a moveably arranged electromagnetic primary coil, adjustment means for adjusting the position of the primary coil, and a control unit for controlling the position of the primary coil to a predefined distance above, but not in contact with, an upper free surface of the molten metal. The molten metal may be contained in a foundry crucible during manufacturing. The system can be used as an additive manufacturing system, with the primary coil arranged above the melt pool. A secondary low-frequency electromagnetic coil may be arranged around and at a distance from the molten metal to induce flow and/or vibrations in the molten metal.

Abstract: A multiport distribution network is provided that supports N inputs and N outputs, where N>1, the multipart distribution network providing an independent distribution path extending from each input to each output, each path being formed from a sequence of at least two fundamental units. Each fundamental unit comprises a circuit formed of multiple resonator cavities and having n input ports for receiving respective input signals, and n output ports for outputting respective output signals, where n>1, and wherein the circuit is configured to: (i) at each input port, split an input signal received at that input port into n equal signal components and provide each of the n signal components to a respective output port of the circuit; and (ii) at each output port, combine the signal components received from the n input ports to form an output signal for that output port. The multipart distribution network is configured to apply the same filter transfer function along each independent distribution path.

Abstract: An imaging spectrometer receives a beam of light from a slit and outputs the beam of light to a focal plane. The output beam of light at the focal plane is dispersed in accordance with a spectral composition of the beam of light received from the slit. The imaging spectrometer comprises first to fourth curved reflective portions. The first to fourth curved reflective portions are arranged so that the beam of light, in its passage from the slit to the focal plane, sequentially strikes the first to fourth curved reflective portions and is reflected by the first to fourth curved reflective portions. Further, the first to fourth curved reflective portions are alternatingly concave or convex, respectively, along the passage of the beam of light. At least one of the first to fourth curved reflective portions has a reflective grating structure. Further disclosed is a method of manufacturing such imaging spectrometer.

Abstract: A foil deployment mechanism comprises a first drum rotatable about a first longitudinal axis, and a second drum rotatable about a second longitudinal axis. The foil deployment mechanism further comprises a cable, the cable comprising a first section which extends from a lower part of the second drum to an upper part of the first drum, a second section which is wound around a part of the first drum facing away from the second drum, a third section which extends from a lower part of the first drum to an upper part of the second drum, and a fourth section which is wound around a part of the second drum facing away from the first drum, wherein the first section and the third section intersect each other between the first drum and the second drum when being viewed along the first longitudinal axis.