Abstract: A synthetic aperture radar (SAR) for a flight vehicle may include an elongate phased array antenna oriented with a long axis in an elevation direction. The elevation direction is normal to a direction of flight of the flight vehicle. A transmitter is coupled to the elongate phased array antenna, and a receiver is coupled to the elongate phased array antenna. A controller is coupled to the transmitter and receiver and is configured to generate temporally alternating sets of receive beams for respective swaths to be used to form a SAR image across a surface below the flight vehicle. The same center frequency is used to create consistent SARs for all swaths, allowing for coherent combination between subsequent passes over the same swath.

Abstract: A deployable space antenna may include a housing and a first telescoping boom and a second telescoping boom extendable from the housing in opposite directions from a stowed position to a deployed position. Each of the first and second telescoping booms may include telescoping boom segments. Each of a plurality of deployable, steerable antennas is carried by respective telescoping boom segment and movable between a stowed position and a deployed position. An antenna controller is configured to steer the deployable, steerable antennas.

Abstract: A spaceborne antenna for a satellite may include antenna sections for the satellite, and at least one rolling flex hinge rotatably coupling first and second antenna sections together and permitting rotation between a stored position and a deployed position. The first and second antenna sections may be stacked in the stored position and extended in end-to-end relation in the deployed position. The at least one rolling flex hinge may include a first hinge body coupled to an end of the first antenna section, a second hinge body coupled to an end of the second antenna section, and a flexible strap arrangement coupling the first hinge body and second hinge body together to permit rolling contact therebetween. At least one locking linkage may be coupled between the first and second hinge bodies to lock the first and second hinge bodies when the first and second antenna sections are in the deployed position.

Abstract: A space antenna may include an extendible boom movable between stored and deployed positions. An extendible hoop may surround the extendible boom and is movable between the stored and deployed positions. A front cord arrangement may be coupled to the extendible hoop and defines a curved shape in the deployed position, and a reflective layer may be carried thereby. A rear cord arrangement may be behind the front cord arrangement and coupled between the extendible hoop and the extendible boom. The rear cord arrangement may include a rear plurality of interconnected cords defining rear polygons. Tie cords may extend between the front cord arrangement and the rear cord arrangement. A top cord arrangement may be above the reflective layer and coupled between the hoop and the extendible boom.

Abstract: A spaceborne antenna for a satellite may include antenna sections for the satellite, and at least one rolling flex hinge rotatably coupling first and second antenna sections together and permitting rotation between a stored position and a deployed position. The first and second antenna sections may be stacked in the stored position and extended in end-to-end relation in the deployed position. The at least one rolling flex hinge may include a first hinge body coupled to an end of the first antenna section, a second hinge body coupled to an end of the second antenna section, and a flexible strap arrangement coupling the first hinge body and second hinge body together to permit rolling contact therebetween. At least one locking linkage may be coupled between the first and second hinge bodies to lock the first and second hinge bodies when the first and second antenna sections are in the deployed position.

Abstract: A synthetic aperture radar (SAR) for a flight vehicle may include an elongate phased array antenna oriented with a long axis in an elevation direction. The elevation direction is normal to a direction of flight of the flight vehicle. A transmitter is coupled to the elongate phased array antenna, and a receiver is coupled to the elongate phased array antenna. A controller is coupled to the transmitter and receiver and is configured to generate temporally alternating sets of receive beams for respective swaths to be used to form a SAR image across a surface below the flight vehicle. The same center frequency is used to create consistent SARs for all swaths, allowing for coherent combination between subsequent passes over the same swath.

Abstract: A space antenna may include an extendible boom movable between stored and deployed positions. An extendible hoop may surround the extendible boom and is movable between the stored and deployed positions. A front cord arrangement may be coupled to the extendible hoop and defines a curved shape in the deployed position, and a reflective layer may be carried thereby. A rear cord arrangement may be behind the front cord arrangement and coupled between the extendible hoop and the extendible boom. The rear cord arrangement may include a rear plurality of interconnected cords defining rear polygons. Tie cords may extend between the front cord arrangement and the rear cord arrangement. A top cord arrangement may be above the reflective layer and coupled between the hoop and the extendible boom.

Abstract: Systems and methods for operating an antenna with a tension cord network coupled to a plurality of anchor points of a perimeter hoop structure. The methods comprise: using the tension cord network to support a flexible antenna reflector surface such that a given shape of the flexible antenna reflector surface is provided; and allowing locations of the anchor points to change relative to the tension cord network while the antenna is in use. The flexible antenna reflector surface is held taut when the locations of the anchor points change relative to the tension cord network.

Abstract: Perimeter truss reflector includes a perimeter truss assembly (PTA) comprised of a plurality of battens, each having an length which traverses a PTA thickness as defined along a direction aligned with a reflector central axis. A collapsible mesh reflector surface is secured to the PTA such that when the PTA is in a collapsed configuration, the reflector surface is collapsed for compact stowage and when the PTA is in the expanded configuration, the reflector surface is expanded to a shape that is configured to concentrate RF energy in a predetermined pattern. Each of the one or more longerons extend around at least a portion of a periphery of the PTA. These longerons each comprise a storable extendible member (SEM) which can be flattened and rolled around a spool, but exhibits beam-like structural characteristics when unspooled.

Abstract: A satellite includes first and second extensible pantographic trusses, each configured to extend outwardly from the satellite in opposite directions from a stored position to a deployed position, and first and second sets of ribs carried by the respective first and second extensible pantographic trusses. A Radio Frequency (RF) reflective film may be carried by the first and second sets of ribs to define a curved RF reflector surface. The satellite antenna may include first and second sets of phased array antenna feeds carried by the respective first and second extensible pantographic trusses and directed toward the RF reflective film, which in an example may be a RF reflective mesh.

Abstract: A radar antenna for a flight vehicle that follows a flight path comprises a radio frequency (RF) reflector, and separated first arrays of first RF feed elements to form, with the reflector, respective first fixed radar beams that are directed at the Earth and positionally offset with respect to each other, such that when the radar antenna follows the flight path, the respective first fixed radar beams trace respective first subswaths on the Earth that are separated from each other by respective subswath gaps.

Abstract: A satellite includes first and second extensible pantographic trusses, each configured to extend outwardly from the satellite in opposite directions from a stored position to a deployed position, and first and second sets of ribs carried by the respective first and second extensible pantographic trusses. A Radio Frequency (RF) reflective film may be carried by the first and second sets of ribs to define a curved RF reflector surface. The satellite antenna may include first and second sets of phased array antenna feeds carried by the respective first and second extensible pantographic trusses and directed toward the RF reflective film, which in an example may be a RF reflective mesh.

Abstract: Systems and methods for extending a boom. The methods comprise: placing a drive train assembly in a start configuration in which an engagement member of the drive train assembly is coupled to an inner telescoping segment of the boom; rotating a spool in a first direction so as to unwind a slit-tube that is coupled to the engagement member; causing the inner telescoping segment to move in a direction away from a proximal end of the boom as the slit-tube is being unwound from the spool; and coupling the inner telescoping segment to an adjacent telescoping segment when the inner telescoping segment reaches an extended position. The slit-tube extends a distance inside the boom that is equal to or less than a length of the adjacent telescoping segment when the inner telescoping segment is in the extended position.

Abstract: A reflector antenna system comprising: a hoop assembly configured to expand between a collapsed configuration and an expanded configuration; a mesh reflector secured to the hoop assembly such that when the hoop assembly is in the collapsed configuration the mesh reflector is collapsed within the hoop assembly and when the hoop assembly is in the expanded configuration the mesh reflector is expanded to a shape that is intended to concentrate RF energy in a desired pattern; a mast assembly including an extendible boom to which the hoop assembly is secured by cords; and an antenna feed that is located on a vehicle so as to face a concave surface of the mesh reflector that is intended to concentrate RF energy in the desired pattern.

Abstract: A synthetic aperture radar (SAR) generates concurrent first radar pulses in first frequency channels. The SAR transmits, and receives returns of, the concurrent first radar pulses by first antenna feeds that form first beams in the first frequency channels and that are directed to respective first subswaths of a swath on the Earth separated by subswath gaps. The SAR generates concurrent second radar pulses in second frequency channels. The SAR transmits, and receives returns of, the concurrent second radar pulses by second antenna feeds configured to form second beams in the second frequency channels and that are directed to respective second subswaths of the swath on the Earth and that coincide with the subswath gaps. The SAR processes the returns of the first radar pulses from the first subswaths and the returns of the second radar pulses from the second subswaths to form a SAR image contiguous across the swath.

Abstract: Systems and methods for operating a reflector system. The methods comprise: structurally supporting a mesh reflector surface using a circumferential hoop that is coupled to a boom via cords; supporting the circumferential hoop using a series of cords extending at least from a base structure of the reflector system to the circumferential hoop and from the boom to the circumferential hoop (where the line of action of all the cords intersect an axis of symmetry of the circumferential hoop); and preventing rotation of the circumferential hoop using at least a first set of additional cords extending from the base structure of the reflector system to the circumferential hoop (where the additional cords of the first set both point to a first point that is horizontally offset from the axis of symmetry).

Abstract: Systems and methods for deploying an extendable reflector structure. The methods comprise: transitioning the extendable reflector structure from a stored configuration to a deployed configuration; and causing expansion of a pantograph coupling structure while the extendable reflector structure is being transitioned from the stored configuration to the deployed configuration. The pantograph coupling structure indirectly couples the extendable reflector structure to a boom such that a beam produced by the extendable reflector structure during operation is offset from a focal axis of the extendable reflector structure by a certain amount.

Abstract: Systems and methods for deploying an extendable reflector structure. The methods comprise: transitioning the extendable reflector structure from a stored configuration to a deployed configuration; and causing expansion of a pantograph coupling structure while the extendable reflector structure is being transitioned from the stored configuration to the deployed configuration. The pantograph coupling structure indirectly couples the extendable reflector structure to a boom such that a beam produced by the extendable reflector structure during operation is offset from a focal axis of the extendable reflector structure by a certain amount.

Abstract: Perimeter truss reflector includes a perimeter truss assembly (PTA) comprised of a plurality of battens, each having an length which traverses a PTA thickness as defined along a direction aligned with a reflector central axis. A collapsible mesh reflector surface is secured to the PTA such that when the PTA is in a collapsed configuration, the reflector surface is collapsed for compact stowage and when the PTA is in the expanded configuration, the reflector surface is expanded to a shape that is configured to concentrate RF energy in a predetermined pattern. Each of the one or more longerons extend around at least a portion of a periphery of the PTA. These longerons each comprise a storable extendible member (SEM) which can be flattened and rolled around a spool, but exhibits beam-like structural characteristics when unspooled.

Abstract: Deployable reflector antenna includes a fabrication hub in which at least one additive fabrication unit disposed. The additive fabrication unit is configured to form at least one rigid structural element of a reflector antenna system. In a stowed condition, an RF reflector material comprised of a flexible webbing is disposed in a stowed configuration proximate to the fabrication hub. A fabrication control system controls the additive fabrication unit so as to form the at least one rigid structural element. The RF reflector material is arranged to transition during the additive fabrication process from the stowed configuration in which the flexible webbing material is furled compactly at the fabrication hub, to a deployed configuration in which the flexible webbing material is unfurled.