A deployable membrane structure for an antenna comprises a membrane comprising a plurality of first regions of higher-stiffness material integrally connected via one or more second regions of lower-stiffness material, wherein the one or more second regions are formed from compliant material configured to permit the membrane to be folded into a collapsed configuration and subsequently unfolded into a deployed configuration, and are arranged so as to allow adjacent ones of the plurality of first regions to be folded so as to lie against one another. In some embodiments the membrane is formed of a composite material comprising a plurality of fibres in a compliant matrix, and the plurality of first regions comprise material with a higher fibre density than the one or more second regions. A deployable antenna comprising the deployable membrane structure is also disclosed.

Methods and systems are described for providing end-to-end beamforming. For example, end-to-end beamforming systems include end-to-end relays and ground networks to provide communications to user terminals located in user beam coverage areas. The ground segment can include geographically distributed access nodes and a central processing system. Return uplink signals, transmitted from the user terminals, have multipath induced by a plurality of receive/transmit signal paths in the end to end relay and are relayed to the ground network. The ground network, using beamformers, recovers user data streams transmitted by the user terminals from return downlink signals. The ground network, using beamformers generates forward uplink signals from appropriately weighted combinations of user data streams that, after relay by the end-end-end relay, produce forward downlink signals that combine to form user beams.

An antenna device is disclosed, including a cavity structure having a floor portion and a perimeter wall portion connected to the floor portion. A dipole structure extends upward from a center region of the floor portion inside the cavity structure. At least one of the wall portion and the dipole structure has an opening small enough relative to an expected radio frequency wavelength to avoid affecting antenna performance.

The disclosed method for a communication satellite may include (1) simultaneously generating a first transmission beam to a first ground station and a second transmission beam to each of a plurality of second ground stations in sequence according to a schedule, (2) simultaneously receiving a third transmission beam from the first ground station and a fourth transmission beam from each of the second ground stations in sequence according to the schedule, (3) forwarding first data received via the third transmission beam to each of the second ground stations via the second transmission beam, and (4) forwarding second data received via the fourth transmission beam from each of the second ground stations to the first ground station via the first transmission beam. Various other methods and systems are also disclosed.

An attenuator is configured to attenuate and phase-shift a radiofrequency signal according to a control signal, having a plurality of first attenuation cells (A.sub.1, A.sub.N−1), configured to attenuate said radiofrequency signal by a predetermined value and activated according to a particular bit of the control signal, and implementing a combinatorial logic on the bits of the control signal that are used to control the first attenuation cells, and at least one second attenuation cell (B.sub.1, B.sub.M) configured to attenuate said radiofrequency signal by a predetermined value and activated according to a particular output implementing the combinatorial logic. A control node is also provided for an array antenna having such an attenuator, and an array antenna having an array of such control node and a satellite.

Provided herein is a deployable antenna assembly, a method of deploying an antenna, and systems and methods for sequentially deploying an extendable structure. The deployable antenna assembly includes an extendable pillar configured to extend in an axial direction along a deployment axis of the deployable antenna assembly to deploy an antenna. The extendable pillar includes at least one extendable element configured to convert between a stowed configuration and a deployed configuration where the deployed configuration is longer in the axial direction than the stowed configuration. The extendable pillar also includes a launcher configured to initiate conversion of the plurality of extendable elements from the stowed configuration to the deployed configuration, thereby extending the extendable pillar and deploying the antenna.

A multibeam antenna comprises a direct radiating array (DRA) comprising a plurality of radiating elements, a reflector facing the DRA so as to reflect a field generated by the DRA, and a DRA controller configured to control the plurality of radiating elements of the DRA according to a plurality of coefficients, such that the field generated at the DRA produces a plurality of beams when reflected by the reflector. The DRA controller is configured to determine the plurality of coefficients by using a bifocal antenna model to determine a field that would be produced by a subreflector and feed horn arrangement in an equivalent bifocal antenna configured to produce the plurality of beams, and determining the plurality of coefficients required to produce a similar incident field at the surface of the reflector. A method of controlling the multibeam antenna, and corresponding computer program instructions stored on a non-transitory computer-readable storage medium, are also disclosed.

Technologies directed to a slot antenna as a calibration antenna for a phased array antenna are described. The antenna structure includes a ground plane, a first antenna element, and a second antenna element. The first antenna element and the second antenna element are located in a first plane that is separated from the ground plane by a first distance. The second antenna element is separated from the first antenna element by a second distance. Conductive material is located in the first plane the first antenna element and the second antenna element. A portion of the conductive material adjacent to the first antenna element includes a slot antenna. A radio frequency feed point is located at the slot antenna. The conductive material electrically isolates the first antenna element and the second antenna element and radiates electromagnetic energy as a slot antenna.

A removeable satellite antenna pointing tool can include a mounting gear releasably engageable with a pole that supports a satellite antenna. The removeable satellite antenna pointing tool can also include an azimuth gear subsystem housed in a frame and engaged with the mounting gear and a motor that drives the azimuth gear subsystem, wherein actuation of the motor causes the frame to rotate about the pole. The removeable satellite antenna pointing tool can further include a linear drive that controls an elevation of a control shaft engageable with a fixture attached to the satellite antenna. Actuation of the motor can change an azimuth of the satellite antenna and actuation of the linear drive can change an elevation of the satellite antenna.

[Problem] To provide a spacecraft having a more effective arrangement of amplifiers. [Solution] Provided is a spacecraft comprising: a main body having a housing space for housing an electronic device within; an oscillator configured to output a radio wave including a frequency in a predetermined frequency band; an amplifier disposed on an exterior of the main body so as to be exposed to space and configured to amplify the power of the radio wave output by the oscillator; and an antenna, disposed on the exterior of the main body, for emitting the radio wave to the outside at the power amplified by the amplifier.