Abstract: In summary the present invention discloses a horn reflect array antenna system and a method for producing a signal using a horn reflect array antenna. The system comprises at least one reflective element illuminated by an incident radio frequency (RF) signal from a feed horn, the reflective element reflecting a portion of the incident RF signal as a portion of a reflected RF signal, and at least one phase shifting device, each phase shifting device coupled to a corresponding reflective element, wherein a beam pattern of the reflected RF signal is altered when the phase shifting element changes the phase of the portion of the reflected RF signal.

Abstract: A communication system and method for reconfigurably transmitting and receiving signals via a multi-beam reflector antenna array are disclosed. The multi-beam antenna system comprises a plurality of rings of single beam reflectors, each reflector having its own feed, wherein the plurality of rings are substantially concentric or nested and disposed on separate planes such that the reflectors of adjacent rings are substantially interleaved. The method, in one embodiment, comprises generating beams from a first, second and third ring of single beam feeds, respectively reflecting each beam from the first, second and third ring of single beam feeds on a separate reflector to a substantially separate coverage area, wherein the first, second and third rings are substantially concentric and disposed on separate planes such that the reflectors of adjacent rings are substantially interleaved.

Abstract: A communication system and method for reconfigurably transmitting and receiving signals via a multi-beam reflector antenna array are disclosed. The multi-beam antenna system comprises a plurality of rings of single beam reflectors, each reflector having its own feed, wherein the plurality of rings are substantially concentric or nested and disposed on separate planes such that the reflectors of adjacent rings are substantially interleaved. The method, in one embodiment, comprises generating beams from a first, second and third ring of single beam feeds, respectively reflecting each beam from the first, second and third ring of single beam feeds on a separate reflector to a substantially separate coverage area, wherein the first, second and third rings are substantially concentric and disposed on separate planes such that the reflectors of adjacent rings are substantially interleaved.

Abstract: The present invention discloses a method for generating multiple antenna beams and a system for generating multiple antenna beams. The system comprises a first reflector surface that has a primary and at least a first auxiliary surface, and a second reflector surface, and also comprises first, second, and third feed horns. The first feed horn illuminates the primary surface with radio frequency (RF) energy, the second feed horn illuminates the auxiliary surface with RF energy, and the third feed horn illuminates the second reflector surface with RF energy. The first feed horn and third feed horn are removed from an axis of symmetry of the first auxiliary surface.

Abstract: An antenna system and method for generating a desired contiguous spot beam pattern, and a signal is disclosed. The contiguous spot beam generating antenna system comprises a reflector system configured in a side-fed Cassegrain (SFOC) configuration, an array of feed horns comprising at least a subset of feed horns for illuminating the reflector system, and a beamforming network, communicatively coupled to the array of feed horns, for controlling an excitation of the subset of the feed horns in the array of feed horns. The method comprises illuminating a side fed offset Cassegrain reflector system with an RF signal emanating from an array of feed horns, and controlling an excitation of the subset of the feed horns.

Abstract: A method and apparatus for producing contiguous spot beam communications coverage on the Earth's surface are disclosed. The apparatus comprises an antenna system including two wide scan antennas and two narrow scan antennas. The two wide scan antennas are disposed substantially opposite each other, and the two narrow scan antennas are disposed substantially opposite each other and substantially normal to the wide scan antennas. The first wide scan antenna, second wide scan antenna, and first narrow scan antenna produce a first beam pattern on a planetary surface and the first wide scan antenna, second wide scan antenna, and second narrow scan antenna produce a second beam pattern on the planetary surface.

Abstract: A reconfigurable payload for a satellite having a flexible antenna system, a variable downconverter technology and a filter technology that all work in combination to allow the payload of a satellite to be reconfigured in orbit.

Abstract: An antenna system having a rotatable and scannable reconfigurable shaped reflector with a movable feed system. The antenna system allows beam shapes to be rotated about an optimum axis and defocused while a spacecraft is in orbit in order to change a particular coverage pattern for the spacecraft.

Abstract: An antenna system comprising a first reflector and a second reflector is disclosed. The first reflector reflects an incident signal from a signal source. The incident signal comprises a first signal having a first polarization and a second signal having a second polarization. The first reflector has a surface that reflects the first signal and the second signal. The second reflector receives the reflected incident signal from the first reflector and comprises a first reflective surface for reflecting the first signal and a second reflective surface for reflecting the second signal.

Abstract: A tunable polarizer having a 90 degree phase shift section and two adjustable, or rotatable, 45 degree phase shift sections. Each section is separated by spacer to maintain independence and avoid interaction. When the two 45 degree phase shift sections and are orthogonal to each other, the polarization detected is determined by the 90 degree phase shift section which provides compatibility with circularly polarized signal. When the two 45 degree phase shift sections and are aligned, the polarizer is in a linear polarization compatibility mode.

Abstract: A unique feed structure for improving the cross-polarization performance of a reflector antenna system is disclosed. According to the present invention, the feed structure is an array including a number of feeds, which are rotated in a predetermined fashion to yield superior cross polarization performance of the antenna system. The array feed in the center of the feed structure is positioned approximately in the focus of the antenna reflector. The array feeds located on the y-axis are slightly rotated in either a clockwise or a counter-clockwise manner. The magnitude of the rotation is proportional to the distance of the feeds from the x-axis along the y-axis. The rotation of the feeds yields significant performance in cross polarization performance, while having little or no co-polarization effect.

Abstract: A dual band omni directional antenna is disclosed. A dielectric cylinder supports a cone shaped reflector over a corrugated radio frequency horn. Orthogonal mode transducers produce and conduct circularly polarized radio frequency waves within the horn. The reflector, the horn, and the transducers are all coaxially disposed. The antenna produces a torodial radiation pattern in a plane that is substantially orthogonal to the axis of the antenna. Transmit and receive functions may be performed simultaneously using a single reflector and two orthogonal mode transducers.

Abstract: An improved dual gridded reflector antenna configuration which allows cross-polarization radiation to be scanned in any given direction. The dual-gridded reflector assembly includes a front parabolic reflector illuminated by a first source, and a second parabolic reflector illuminated by a second source. The second reflector is positioned adjacent to and behind the front reflector such that the center points of the reflectors align to define a center axis. Additionally, the first and second sources are positioned at different offsets with respect to the reflectors and have a respective rotated offset angle with respect to the center axis such that the sources define an antenna feed separation. By modifying the offsets and the rotated offset angles, the feed separation can be designed to have an inclination with respect to the north-south or east-west feed separation direction.

Abstract: A system and method for changing the radiation pattern of an antenna assembly of a satellite in orbit is provided. The antenna assembly includes a reflector antenna fed by a feed assembly. The reflector antenna transmits and receives signals within a radiation pattern. The reflector antenna and the feed assembly are movably mounted to a sliding mechanism so that they can be displaced with respect to one another. The displacement causes defocusing as the reflector antenna is displaced from the focus point. The defocusing causes the radiation pattern to become more compact or broadened. Thus, the radiation pattern of the satellite provided with a single reflector antenna and a single feed element may be changed while the satellite is in orbit. The system and method include gimballing the reflector antenna to steer the radiation pattern.

Abstract: A reconfigurable multiple beam array antenna for transmitting beams includes a reflector and radiating elements for feeding beam signals to the reflector. The array antenna includes a reconfigurable beam forming network having a plurality of dividers, a plurality of adjustable phase shifter and attenuator pairs, and a plurality of combiners to form beam signals from beam signals input to the beam forming network. A first hybrid matrix formed by an association of couplers is connected to the beam forming network for receiving the beam signals. Amplifiers receive and amplify the beam signals from the first hybrid matrix. A second hybrid matrix formed by an association of couplers is connected to the amplifiers for receiving the beam signals. The second hybrid matrix provides the amplified beam signals to the radiating elements for the reflector to transmit beams.

Abstract: A reconfigurable multiple beam phased array antenna has radiating elements arranged in a planar array and variable phase shifters. Each one of the phase shifters is connected to a respective one of the radiating elements. The array antenna further includes a beam forming network for forming spot and regional beam signals. The beam forming network forms a regional beam signal from a combination of spot beam signals. The beam forming network has two dimensional stacks of Rotman lenses provided with a first set of ports. Each one of the first set of ports is connected to a respective one of the radiating elements with. The Rotman lenses generate frequency invariant spot beam signals which are communicated between the radiating elements and the Rotman lenses via the first set of ports for transmission and reception of spot beams and regional beams by the radiating elements. The phase shifters are adjusted to steer the spot and regional beams to desired locations.

Abstract: A pair of dual-gridded shaped reflectors (10) and (20) are arranged one behind the other for transmitting and receiving orthogonally polarized energy waves. A front reflector (10) has a first shaped reflective surface (12) formed on a first body surface (14) for providing a first shaped beam coverage. A rear reflector (20) has a second reflective surface (22) formed on a second body surface (24) for providing a second shaped beam coverage. The first and second reflective surfaces (12) and (22) have substantially identical surface contours and include reflective grids (13) and (23). The reflective grids (13) and (23) are orthogonal with respect to each other so as to handle orthogonally polarized energy. The first and second shaped reflective surfaces (12) and (22) are arranged offset and tandem from each other so as to provide first and second focal points (16) and (26) separate from each other while providing substantially identical first and second shaped beam coverages (15) and (25).

Abstract: A satellite-based communication system providing high rate transfer of data between linked terminals. The system comprises a plurality of user terminals (VSAT's) that are linked by and that communicate with each other by way of a satellite-based relay system. A network control center provides configuration signals that control the satellite relay system and coordinate linking of terminals to each other. Frequency division multiplexing uplinks are used from the terminals and the network control center to the satellite relay system. Time division multiplexing are used on downlinks from the satellite relay system to the terminals and the network control center. Each user terminal comprises a data compression and decompression circuit, a transceiver, and an antenna for transmitting and receiving data to and from the satellite relay system. The satellite relay system comprises a satellite, a wide area antenna, a plurality of receive antennas, a plurality of transmit antennas, and a signal processor.

Abstract: A dual-reflector antenna system (40) is provided for generating a shaped main beam radiation pattern (20) and at least one additional secondary spot beam radiation pattern (30,32). The antenna system (40) includes a main shaped reflector (10) having a shaped reflective surface (11) operatively coupled to a subreflector (12) for communicating therewith. A main feed horn (14) communicates directly with the subreflector (12) so as to reflect first energy to and from the main reflector (10) within a shaped beam radiation pattern (20). In a preferred embodiment, the subreflector (12) has an ellipsoidal reflective surface (13) which communicates directly with the main reflector (10) via an inverted reflective path (17) which has a converging focal point (18). One or more auxiliary feed horns (24,26) are operatively coupled directly to the main reflector so as to directly communicate therewith and reflect second energy within one or more additional radiation patterns (30,32).

Abstract: Equalized offset fed east and west shaped reflectors (12) and (14) and technique for producing the same are provided herein. A first shaped reflector (12) has a first shaped reflective surface (3) formed to provide a first shaped beam radiation pattern (22). Dimensional deviations such as deviations (X) and (Y) are measured between the first shaped reflective surface (13) and a parent surface (30). A second shaped reflector (14) is formed with a shaped reflective surface (15) which has dimensional deviations superimposed on the other side of the parent surface (30). The second shaped reflector (12) is rotated 180 degrees relative to the first shaped reflector (14). The first and second shaped reflectors (12) and (14) are then placed in a configuration opposite one another and have shaped beam radiation patterns (22) and (24) which are substantially equal to one another. In addition, feed horns (18) and (20) are operatively coupled to the first and second shaped reflective surfaces (13) and (15) respectively.