Abstract: A system and method of resolving a time ambiguity in a receiver based on a received radio signal. The radio signal includes a first signal component and a second signal component. The first and second signal components include code symbols having durations of time The system and method include acquiring each of the signal components, and performing code symbol synchronization and/or code synchronization for each of the codes. The system and method further include estimating a code phase offset between the synchronized codes, or a code-symbol phase offset between the synchronized code symbols. Finally, the system and method include resolving the time ambiguity of the receiver within a time period based on the time-dependent code phase offset or the time-dependent code-symbol phase offset.

Abstract: An aggregated communication network includes one or more communication networks and a plurality of network nodes arranged in a plurality of hierarchical layers, the network nodes including a central node at a highest layer and a remaining network nodes being arranged, as part of the one or more communication networks, in layers below the highest layer, with one or more spatially distributed network nodes at each layer below the highest layer. The network nodes in each communication network are interconnected in a tree-like structure via communication links, with respective sub-branches extending from the network nodes via network nodes in lower layers. The one or more communication networks are connected to the central node in a star-like structure via respective communication links between the central node and respective network nodes in a next-to-highest layer. The communication links between network nodes in a lowest layer.

Abstract: A waveguide power divider device comprises four two-port orthomode junctions arranged with their common waveguides extending in parallel, wherein the two ports of each orthomode junction extend in orthogonal directions, four E-plane T-junctions, each T-junction coupling two of the four orthomode junctions to each other via respective ones of their ports, a four-port turnstile junction, wherein waveguides of the four ports are bent to extend in parallel to an extension direction of a common waveguide of the turnstile junction, and four waveguide twists, each waveguide twist coupling a common waveguide of a respective one of the T-junctions to the waveguide of a respective one of the ports of the turnstile junction, with broad walls of the common waveguide of the T-junction and of the waveguide of the port of the turnstile junction being orthogonal to each other. An array antenna may include one or more such waveguide power divider devices.

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 method of determining a phase shift caused by reflection at, or transmission through, a dielectric coating as a function of wavenumber includes obtaining a nominal phase shift for the dielectric coating as a function of wavenumber, determining a first wavenumber and a second wavenumber for performing measurements of phase shift at these wavenumbers based on the nominal phase shift, determining a wavenumber shift based on a first measurement of phase shift at the first wavenumber, a second measurement of phase shift at the second wavenumber, and the nominal phase shift as a function of wavenumber, and determining the phase shift as a function of wavenumber based on the wavenumber shift and the nominal phase. Further described is a method of determining a layer design for a dielectric coating, wherein the dielectric coating comprises a plurality of stacked layers.

Abstract: A satellite communication system includes a first satellite in a geostationary orbit and a plurality of second satellites. Each of the second satellites is in a separate orbit with time-dependent projection on ground. The first satellite is adapted to communicate with one or more user terminals and to communicate with each of the plurality of second satellites via a respective inter-satellite communication link. Further, each of the second satellites is adapted to communicate with one or more feeder link stations. Also disclosed is a method of communicating in a satellite communication system.

Abstract: A beamforming network for use with a plurality of antenna elements arranged in a planar array of linear sub-arrays includes first and second sets of beamforming sub-networks. Each beamforming sub-network in the first set of beamforming sub-networks is associated with a respective one of the linear sub-arrays and is adapted to generate, via the associated linear sub-array, fan beams along respective beam directions in a first set of beam directions. Each beamforming sub-network in the second set of beamforming sub-networks is associated with a respective one of the beam directions in the first set of beam directions. For each beamforming sub-network in the second set of beamforming sub-networks, each of the output port is coupled to an input port of a respective beamforming sub-network in the first set of beamforming sub-networks that corresponds to the associated beam direction. The application further relates to a multibeam antenna comprising such beamforming network.

Abstract: A space vehicle element configured to be at least partially destroyed during re-entry of a space vehicle into the atmosphere comprises a heat generating part comprising a metallo-thermal composition for providing additional heat during re-entry of the space vehicle into the atmosphere by an exothermic reaction of the metallo-thermal composition. The destruction of the space vehicle element is expedited by the additional heat provided by the heat generating part. The heat generating part is at least partially integrated within the space vehicle element or at least partially surrounds a portion of the space vehicle element. The application further relates to a corresponding method of manufacturing a space vehicle element configured to be destroyed during re-entry of the space vehicle into the atmosphere.

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 space vehicle includes one or more magnetorquers operable to change an attitude of the space vehicle in an external magnetic field, each magnetorquer comprising a coil, and a switching circuit for short-circuiting the coil of at least one of the magnetorquers so that a closed electric circuit comprising said coil is formed, for damping tumbling motion of the space vehicle in the external magnetic field. The switching circuit is configured to short-circuit the coil of the at least one magnetorquer upon occurrence of a condition indicative of end-of-life or failure of the space vehicle. The application further relates to a corresponding method of operating a space vehicle.

Abstract: The method involves sequentially encoding the plurality of data packets, which involves, for a data packet, obtaining a reference data packet, obtaining a mask packet indicative of which of the bits in the data packet are predictable and which of the bits in the data packet are not predictable obtaining change history data indicative of previously changed bits of the mask packet, determining an updated mask packet based on the mask packet, the data packet, and the reference data packet, determining updated change history data based on the change history data, the mask packet, and the updated mask packet, determining, as unpredictable bits, all those bits of the data packet that are indicated as not predictable by the updated mask packet, and generating an encoded data packet including a representation of the updated change history data and a representation of values of the unpredictable bits of the data packet.

Abstract: The method involves sequentially encoding the plurality of data packets, which involves, for a data packet, obtaining a reference data packet, obtaining a mask packet indicative of which of the bits in the data packet are predictable and which of the bits in the data packet are not predictable obtaining change history data indicative of previously changed bits of the mask packet, determining an updated mask packet based on the mask packet, the data packet, and the reference data packet, determining updated change history data based on the change history data, the mask packet, and the updated mask packet, determining, as unpredictable bits, all those bits of the data packet that are indicated as not predictable by the updated mask packet, and generating an encoded data packet including a representation of the updated change history data and a representation of values of the unpredictable bits of the data packet.

Abstract: A method for design an optimized constellation set and labeling for satellite point to multi-point transmission systems including transmitters and receivers, wherein the transmitters are adapted to create signals overlay and are configured to allow simultaneous transmission of at least two different data streams (services) intended for users with different radio link qualities. In particular, N services are provided to users having a good radio link and a subset of services is maintained and guaranteed for the users having a lower radio link quality condition.

Abstract: A receiver is provided for use with a global navigation satellite system (GNSS) comprising multiple satellites. The receiver comprises a receiver clock and at least one antenna for receiving multiple signals over multiple respective channels, each channel being defined by a transmitting satellite and a receiving antenna at opposing ends of the channel. The receiver further comprises at least one correlator for calculating cross-correlation functions between (i) the signals received over the multiple channels and (ii) reference versions of the navigation signals provided by the receiver. The receiver is configured to use the calculated cross-correlation functions to perform a joint estimate of (i) a clock bias of the receiver clock relative to the time reference maintained by the GNSS, and (ii) a composite channel comprising the combined contribution of the multiple channels as a function of time-delay.

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: 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: 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.