Abstract: Described herein is a power processing unit (PPU) for use with a Hall Effect Thruster (HET) and a Propellant Management Assembly (PMA) of a spacecraft. The PPU comprises an anode and ignitor supply subsystem that provides anode and ignitor signals to an anode and an ignitor circuit of the HET. The PPU also comprises a valve control subsystem that provides valve control signal(s) to valve(s) of the PMA. The anode and ignitor supply subsystem and the valve control subsystem are each coupled to a low voltage (LV) bus of an electrical power subsystem of the spacecraft. The anode and ignitor supply subsystem includes a step-up DC-DC converter having a transformer that steps-up a voltage of the LV bus to a higher voltage used to produce the anode and ignitor signals. The valve control subsystem is devoid of a transformer. An Electric Propulsion System (EPS) includes the PPU, HET and PMA.

Abstract: An articulated mechanism is included in an articulated pointing system. The articulated mechanism includes first, second, and third spherical joints, and a first, second, and third lever. The first and second spherical joints are linked by the first lever. The first lever includes a first projecting portion. The first and third spherical joints are linked by the second lever, the second lever including a second projecting portion projecting in an opposite direction of the first projecting portion. The second and third spherical joints are linked by the third lever, such that the longitudinal axes of the first lever and of the second lever are perpendicular. The articulated pointing system includes a basement platform and a mobile platform joined by two articulated hinges. The hinges are moved by actuators. The articulated mechanism has the first lever attached to the mobile platform and the second lever attached to the basement platform.

Abstract: In one embodiment of the present disclosure, an antenna assembly includes a plurality of layers defining an antenna assembly including a plurality of PCB layers and a plurality of non-PCB layers, the antenna assembly having a top surface and a bottom surface, and adhesive coupling between the PCB layers and the non-PCB layers.

Abstract: A neutralizer suitable for use in an ion engine comprises a halogen gas source and an electrode tube comprising an inlet opening connected to the halogen gas source for supplying a halogen gas provided by the halogen gas source into the electrode tube, a discharge space for generating a plasma from the halogen gas supplied into the electrode tube, and an outlet opening for discharging the plasma generated in the discharge space and free electrons from the electrode tube. An electron emitter is arranged in the discharge space of the electrode tube, which is at least partially made of tungsten, a tungsten alloy or a tungsten composite material containing at least one of iridium, rhenium, ruthenium, rhodium and osmium.

Abstract: Technology is disclosed herein for a spacecraft launch restraint and dispensing structure. The dispensing structure has a number of trusses and a central structure. When the trusses are in a support position, each spacecraft may be supported at one point by the central structure and at two points by one or more of the trusses. Therefore, each spacecraft may be supported at three points, thereby providing a stable support for each spacecraft. The spacecrafts do not touch each other and do not bear the weight of other spacecrafts. In a deployment position, the trusses extend away from the satellites and do not support the satellites; however, the satellites initially remain connected to the central structure. In the deployment position, the trusses are out of an ejection path such that the satellites can be ejected in a desired sequence from the central structure.

Abstract: Systems, methods, and computer-readable media are provided for hybrid beamforming.

Abstract: A release system for the release of satellites from a launch vehicle is provided that includes: (i) a torsion bar, having a first end which is fixed by means of support means to a launch vehicle and is locked in rotation around a longitudinal axis of the torsion bar, and a second end which is connected by means of hinge means to the launch vehicle and is free to rotate around the longitudinal axis; (ii) at least one launch arm extending perpendicularly from the torsion bar and comprising (a) a torsion lever having a first end which is fixed to the torsion bar in an integral manner, and (b) a guide having a first end connected to a second end of the torsion lever, and a second free end; (iii) at least one slider which is fixed in an integral manner to a satellite to be launched and arranged to engage the guide in a sliding manner; and (iv) and a limit stop element designed to act upon the torsion lever to stop the rotation of the launch arm around the longitudinal axis.

Abstract: An aircraft has a first antenna arrangement, a payload and a processing unit. The first antenna arrangement is designed to wirelessly receive electromagnetic signals. The processing unit is coupled to the first antenna arrangement, on the one hand, and to the payload, on the other hand. The processing unit is designed to modulate an electromagnetic signal received by the first antenna arrangement and thereby to generate a first modulated signal and to forward it to the payload. The payload is designed to use the first modulated signal as working signal. A radiofrequency power signal on an uplink is thus remodulated into a payload working signal, such that the payload working signal is able to be used directly by the payload without rectification into a DC voltage.

Abstract: An attention-based audio adjustment method includes identifying, at a processor and at a first time, a first estimated gaze direction of a first participant within a virtual environment. First audio data is received at the processor from a compute device of the first participant. A second estimated gaze direction of the first participant within the virtual environment is determined by the processor at a second time. Second audio data, different from the first audio data and associated with a virtual representation of a second participant and/or a virtual object, is automatically generated by the processor, based on the first audio data and the second estimated gaze direction. A signal is sent from the processor to the compute device of the first participant, at a third time, to cause an adjustment to an audio output of the compute device of the first participant based on the second audio data.

Abstract: A method and system for Air-To-Ground communications allowing integration of the aircraft communication with a terrestrial cellular communications network. The solution is carried out in the aircraft so any existing standard terrestrial cellular communication network may be used without requiring any modification. The constraints due to the special aircraft conditions (speed and height) are efficiently solved, allowing broad interoperability with the cellular communications network, satisfying the increasing high speed data demand. Specifically, in order to solve the handover constraints the aircraft antenna will create at least two radiation patterns: one for maintaining the current connection with the serving base station and another one or more to search the next suitable best station for handover.

Abstract: A pulsed metal plasma thruster (MPT) cube has a plurality of thrusters, each having a first cathode electrode and a trigger electrode separated from the first electrode by an insulator sufficient to support an initiation plasma, and a porous anode electrode positioned a separation distance from the face of all of the cathode electrodes. The cathode electrode can be either the inner electrode or the outer electrode. A power supply delivers a high voltage pulse to the trigger electrode with respect to the cathode electrode sufficient to initiate a plasma on the surface of the insulator. The plasma transfers between the anode electrode and cathode electrode of selected thrusters, thereby generating a pulse of thrust.

Abstract: A: spacecraft attitude control system comprising •at least one attitude control device (2), the attitude control device comprising •first and second magnets (3, 4) having magnetic dipole moments M1 and M2 respectively, each magnet (3, 4) comprising a north pole face and a south pole face; •the magnets (3, 4) being spaced apart along a length axis by a gap, •for each magnet the pole face closest to the other magnet being termed the closest face, the magnets being arranged with the closest faces being of the same pole; •the first magnet 3 being connected to a rotation mechanism (7), the rotation mechanism being adapted to rotate the first magnet about first and second axes (8, 9), none of the first axis (8), second axis (9) and magnetic dipole moment M1, M2 of the first magnet (3) being parallel to the other.

Abstract: A process for the production of a layer structure of a nitride semiconductor component on a silicon surface, comprising: provision of a substrate having a silicon surface; deposition of an aluminium-containing nitride nucleation layer on the silicon surface of the substrate; optional: deposition of an aluminium-containing nitride buffer layer on the nitride nucleation layer; deposition of a masking layer on the nitride nucleation layer or, if present, on the first nitride buffer layer; deposition of a gallium-containing first nitride semiconductor layer on the masking layer, wherein the masking layer is deposited in such a way that, in the deposition step of the first nitride semiconductor layer, initially separate crystallites grow that coalesce above a coalescence layer thickness and occupy an average surface area of at least 0.16 ?m2 in a layer plane of the coalesced nitride semiconductor layer that is perpendicular to the growth direction.

Abstract: The present invention discloses a method for updating road signs and markings on the basis of monocular images, comprising the following steps: acquiring street images of urban roads and GPS phase center coordinates and spatial attitude data corresponding to the street images; extracting coordinates of the road sign marking images; constructing a sparse three-dimensional model, and then generating a streetscape image depth map; calculating the space position of the road sign and marking according to the semantic and depth values of the image, the collinear equation and the space distance relation; if the same road sign and marking is visible in multiple views, solving the position information of the road sign; and vectorizing the obtained road sign position information, and fusing the information into the original data to realize the updating of the road sign data.

Abstract: A distributed computer system for a spacecraft is disclosed. The system has multiple computer nodes, each controlling a different aspect of a mission of the spacecraft. Each node includes a control circuit(s) that controls a set of components, a router processor, and a programmable processor. The programmable processor of each respective computer node issue commands to the control circuit(s) of the respective computer node to carry out an aspect of the mission associated with the respective computer node. Upon failure of the programmable processor in a particular computer node, a healthy programmable processor send commands to the router processor in the particular computer node The router processor of the particular computer node routes the commands received from the remote programmable processor to the control circuit(s) in the particular computer node to control the set of components to carry out the aspect of the mission associated with particular computer node.

Abstract: The present invention provides an octree-based three-dimensional building model LOD method, specifically comprising the following steps: S1, reading three-dimensional building model data; S2, setting a tree depth Depth parameter of the octree; S3, respectively merging leaf node bounding boxes of the octree according to layers, and establishing coarse grid blocks; S4, merging the coarse grid blocks of the components of each layer; S5, performing triangularization; S6, calculating a normal vector of the coarse grid block; S7, merging the simplified components to form a building model of a coarse grid block; S8, deleting internal vertexes; S9, setting materials or textures; and S10, outputting the three-dimensional building LOD model.

Abstract: A low-earth orbit (LEO) satellite includes a global positioning receiver configured to receive first signaling from a first plurality of non-LEO navigation satellites of a constellation of non-LEO navigation satellites in non-LEO around the earth. An inter-satellite transceiver is configured to send and receive inter-satellite communications with other LEO navigation satellites in a constellation of LEO navigation satellites. At least one processor is configured to execute operational instructions that cause the at least one processor to perform operations that include: determining an orbital position of the LEO satellite based on applying precise point positioning (PPP) correction data to the first signaling, wherein the PPP correction data is received separately from the first signaling; and generating a navigation message based on the orbital position.

Abstract: A stacked multi-junction solar cell with a back-contacted front side, having a germanium substrate that forms a rear side of the multi-junction solar cell, a germanium sub-cell and at least two III-V sub-cells, successively in the named order, and at least one passage contact opening that extends from the front side of the multi-junction solar cell through the sub-cells to the rear side and a metallic connection contact that is guided through the passage contact opening. A diameter of the passage contact opening decreases in steps from the front side to the rear side of the multi-junction solar cell. The front side of the germanium sub-cell forms a first step having a first tread depth that circumferentially projects into the passage contact opening. The second step with a second tread depth circumferentially projects into the passage contact opening.

Abstract: A balloon system including a balloon, and optionally including a payload and/or a safety module. A balloon, preferably including a balloon envelope and one or more passive vents, and optionally including one or more active valves. A method of balloon system operation, preferably including maintaining a zero-pressure balloon condition and sealing balloon vents, and optionally including ascending, descending, and/or otherwise operating the balloon system in flight.