Abstract: An antenna system includes a reflector having a modified-paraboloid shape; and a multi-beam, multi-band feed array located at a focal point of the reflector so that the antenna system forms a multiple congruent beams that are contiguous. The system has a single reflector with non-frequency selective surface. The reflector is sized to produce a required beam size at K-band frequencies and is oversized at EHF-band frequencies. The synthesized reflector surface is moderately shaped and disproportionately broadens EHF-band and Ka-band beams compared to K-band beams. The synthesized reflector surface forms multiple beams each having a 0.5-degree diameter at K-band, Ka-band, and EHF band. The multi-beam, multi-band feed array includes a number of high-efficiency, multi-mode circular horns that operate in focused mode at K-band and defocused mode at Ka-band and EHF-band by employing “frequency-dependent” design for the horns.

Abstract: Methods, systems, and apparatus are disclosed for high power thermal vacuum testing of satellite payloads using pick-up horns. Such pick-up horns can include at least one outer metal wall forming a metal body and at least one interior surface disposed in the metal body, forming at least one chamber in the metal body. The pick-up horn further includes a front metal surface disposed at a front end of the metal body, having at least one opening corresponding to the at least one chamber, and at least one high-power absorbing load disposed within the at least one chamber and in contact with the at least one interior surface. A pick-up horn may further include a serpentine coolant path disposed within the metal body between an outer surface of the at least one outer metal wall and the at least one high-power absorbing load. Related systems and methods are described.

Abstract: An antenna system for transmitting and/or receiving radio frequency (RF) signals in multiple frequency bands includes a horn antenna and a feed network. The horn antenna may transmit and/or receive RF signals in multiple frequency bands that are spread over more than an octave bandwidth with at least a 2.44-to-1 bandwidth ratio. The horn antenna includes a throat, an aperture, and an interior surface. The feed network includes a first waveguide section, a first junction, one or more first filters, and a first step-down waveguide section. The first waveguide section can provide a matching network and transmit and/or receive the RF signals in the multiple frequency bands. The first junction can transmit and/or receive the RF signals in first selected band(s) of the multiple frequency bands. The first step-down waveguide section may transmit and/or receive the RF signals in second selected band(s) of the multiple frequency bands.

Abstract: A stepped reflector for being illuminated by at least one multiple-band feed is provided. The reflector includes a central region and a first annular region with an annular width of w. The first annular region is axially stepped a height h above the central region, where h is approximately equal to m × [ ? ± ( ? ? ( ? = 0 ) - ? ? ( ? = ? 0 ) ) ] × ? 180 × ? 2 ? ? × 1 2 , where m is a positive odd integer, ? is a desired amount of phase shift of an outer region of a phase front for reflecting off of the reflector, ? is a feed phase contribution for an angle ?, and ?0 is an angle formed between an axis of the at least one feed and a line connecting a phase center of the at least one feed and an inner edge of the at least one annular region. The central region and the annular region of the reflector may be parabolically curved or may alternately be shaped. The reflector may be fed by one or more multiple-band horn antennas.

Abstract: An antenna system for generating and configuring at least one defocused beam is provided. The antenna system includes a reflector having a focal plane and a non-parabolic curvature for forming the at least one defocused beam, and a plurality of feed antennas that illuminate the reflector. Each feed antenna is disposed in the focal plane of the reflector. The antenna system further includes at least one incoming signal dividing network that divides at least one incoming signal into a plurality of sub-signals, each corresponding to one of the feed antennas, a plurality of variable phase shifters, each receiving one of the sub-signals from the incoming signal dividing network and phase shifting the sub-signal to generate a corresponding phase-shifted sub-signal, and a plurality of fixed-amplitude amplifiers, at least one corresponding to each of the feed antennas.

Abstract: Methods, systems, and apparatus are disclosed for high power thermal vacuum testing of satellite payloads using pick-up horns. Such pick-up horns can include at least one outer metal wall forming a metal body and at least one interior surface disposed in the metal body, forming at least one chamber in the metal body. The pick-up horn further includes a front metal surface disposed at a front end of the metal body, having at least one opening corresponding to the at least one chamber, and at least one high-power absorbing load disposed within the at least one chamber and in contact with the at least one interior surface. A pick-up horn may further include a serpentine coolant path disposed within the metal body between an outer surface of the at least one outer metal wall and the at least one high-power absorbing load. Related systems and methods are described.

Abstract: A dual-band feed assembly is configured to be coupled to a satellite repeater payload. The dual-band feed assembly includes a transmit filter assembly comprising a transmit pass-band filter configured to reject frequencies outside of a transmit frequency band and a low-pass and harmonic filter configured to reject receive band frequencies and harmonics of the transmit frequency band. The dual-band feed assembly further includes a receive filter assembly comprising a receive pass-band filter configured to reject frequencies outside of a receive frequency band and a high-pass filter configured to reject transmit band frequencies. A multi-port junction couples the transmit and receive waveguide assemblies to a dual-band horn. The dual-band feed assembly also may include receive and transmit test couplers.

Abstract: An antenna system for transmitting and/or receiving radio frequency (RF) signals in multiple frequency bands includes a horn antenna and a feed network. The horn antenna may transmit and/or receive RF signals in multiple frequency bands that are spread over more than an octave bandwidth with at least a 2.44-to-1 bandwidth ratio. The horn antenna includes a throat, an aperture, and an interior surface. The feed network includes a first waveguide section, a first junction, one or more first filters, and a first step-down waveguide section. The first waveguide section can provide a matching network and transmit and/or receive the RF signals in the multiple frequency bands. The first junction can transmit and/or receive the RF signals in first selected band(s) of the multiple frequency bands. The first step-down waveguide section may transmit and/or receive the RF signals in second selected band(s) of the multiple frequency bands.

Abstract: A antenna system for generating and distributing power among a plurality of non-focused beams is provided The system comprises a reflector having a focal plane and a non-parabolic curvature configured to form the defocused beams. The curvature is configured to create a symmetrical quadratic phase-front in an aperture plane of the reflector. The system further comprises a plurality of feed antennas disposed in the focal plane of the reflector and configured to illuminate the reflector. Each feed antenna is configured to contribute power toward each of the defocused beams. The system further comprises a plurality of fixed-amplitude amplifiers, at least one of which corresponds to each feed antenna.

Abstract: A pick-up horn for absorbing radiation emitted by a transmit antenna is provided. The pick-up horn includes at least one outer metal wall forming a metal body and at least one interior surface disposed in the metal body, forming at least one chamber in the metal body. The pick-up horn further includes a front metal surface disposed at a front end of the metal body, having at least one opening corresponding to the at least one chamber, and at least one high-power absorbing load disposed within the at least one chamber and in contact with the at least one interior surface. The pick-up horn may further include a serpentine coolant path disposed within the metal body between an outer surface of the at least one outer metal wall and the at least one high-power absorbing load.

Abstract: Methods, systems, and apparatus are disclosed for high power thermal vacuum testing of satellite payloads using pick-up horns. Such pick-up horns can include at least one outer metal wall forming a metal body and at least one interior surface disposed in the metal body, forming at least one chamber in the metal body. The pick-up horn further includes a front metal surface disposed at a front end of the metal body, having at least one opening corresponding to the at least one chamber, and at least one high-power absorbing load disposed within the at least one chamber and in contact with the at least one interior surface. A pick-up horn may further include a serpentine coolant path disposed within the metal body between an outer surface of the at least one outer metal wall and the at least one high-power absorbing load. Related systems and methods are described.

Abstract: An antenna system includes a reflector having a modified-paraboloid shape; and a multi-beam, multi-band feed array located at a focal point of the reflector so that the antenna system forms a multiple congruent beams that are contiguous. The system has a single reflector with non-frequency selective surface. The reflector is sized to produce a required beam size at K-band frequencies and is oversized at EHF-band frequencies. The synthesized reflector surface is moderately shaped and disproportionately broadens EHF-band and Ka-band beams compared to K-band beams. The synthesized reflector surface forms multiple beams each having a 0.5-degree diameter at K-band, Ka-band, and EHF band. The multi-beam, multi-band feed array includes a number of high-efficiency, multi-mode circular horns that operate in focused mode at K-band and defocused mode at Ka-band and EHF-band by employing “frequency-dependent” design for the horns.

Abstract: Methods, systems, and apparatus are disclosed for high power thermal vacuum testing of satellite payloads using pick-up horns. Such pick-up horns can include at least one outer metal wall forming a metal body and at least one interior surface disposed in the metal body, forming at least one chamber in the metal body. The pick-up horn further includes a front metal surface disposed at a front end of the metal body, having at least one opening corresponding to the at least one chamber, and at least one high-power absorbing load disposed within the at least one chamber and in contact with the at least one interior surface. A pick-up horn may further include a serpentine coolant path disposed within the metal body between an outer surface of the at least one outer metal wall and the at least one high-power absorbing load. Related systems and methods are described.

Abstract: An antenna system includes a reflector having a modified-paraboloid shape; and a multi-beam, multi-band feed array located at a focal point of the reflector so that the antenna system forms a multiple congruent beams that are contiguous. The system has a single reflector with non-frequency selective surface. The reflector is sized to produce a required beam size at K-band frequencies and is oversized at EHF-band frequencies. The synthesized reflector surface is moderately shaped and disproportionately broadens EHF-band and Ka-band beams compared to K-band beams. The synthesized reflector surface forms multiple beams each having a 0.5-degree diameter at K-band, Ka-band, and EHF band. The multi-beam, multi-band feed array includes a number of high-efficiency, multi-mode circular horns that operate in focused mode at K-band and defocused mode at Ka-band and EHF-band by employing “frequency-dependent” design for the horns.

Abstract: A pick-up horn for absorbing radiation emitted by a transmit antenna is provided. The pick-up horn includes at least one outer metal wall forming a metal body and at least one interior surface disposed in the metal body, forming at least one chamber in the metal body. The pick-up horn further includes a front metal surface disposed at a front end of the metal body, having at least one opening corresponding to the at least one chamber, and at least one high-power absorbing load disposed within the at least one chamber and in contact with the at least one interior surface. The pick-up horn may further include a serpentine coolant path disposed within the metal body between an outer surface of the at least one outer metal wall and the at least one high-power absorbing load.

Abstract: A dual-band multiple beam antenna system for a communications satellite sharing a set of reflector antennas for the transmit and receive frequencies. One set of reflectors is common to both the downlink and uplink frequencies. The feed horns are diplexed and exhibit frequency-dependent radiation patterns that separate the phase centers over the downlink and uplink frequency bands to obtain dual-band performance. The focal point of the reflector is in close proximity to the phase center corresponding to the downlink frequency band. The phase center for the uplink frequency band is spaced a predetermined distance from the phase center of the downlink frequency band. According to the present invention, the uplink frequencies are defocused and the downlink frequencies are focused thereby creating identical radiation patterns at both frequency bands and over the coverage region of the communications satellite.

Abstract: A dual-band multiple beam antenna system for a communications satellite sharing a set of reflector antennas for the transmit and receive frequencies. One set of reflectors is common to both the downlink and uplink frequencies. The feed horns are diplexed and exhibit frequency-dependent radiation patterns that separate the phase centers over the downlink and uplink frequency bands to obtain dual-band performance. The focal point of the reflector is in close proximity to the phase center corresponding to the downlink frequency band. The phase center for the uplink frequency band is spaced a predetermined distance from the phase center of the downlink frequency band. According to the present invention, the uplink frequencies are defocused and the downlink frequencies are focused thereby creating identical radiation patterns at both frequency bands and over the coverage region of the communications satellite.

Abstract: An antenna system includes a reflector having a modified-paraboloid shape; and a multi-beam, multi-band feed array located at a focal point of the reflector so that the antenna system forms a multiple congruent beams that are contiguous. The system has a single reflector with non-frequency selective surface. The reflector is sized to produce a required beam size at K-band frequencies and is oversized at EHF-band frequencies. The synthesized reflector surface is moderately shaped and disproportionately broadens EHF-band and Ka-band beams compared to K-band beams. The synthesized reflector surface forms multiple beams each having a 0.5-degree diameter at K-band, Ka-band, and EHF band. The multi-beam, multi-band feed array includes a number of high-efficiency, multi-mode circular horns that operate in focused mode at K-band and defocused mode at Ka-band and EHF-band by employing “frequency-dependent” design for the horns.

Abstract: A method, apparatus, article of manufacture, and a memory structure for generating reconfigurable beams is disclosed herein. The apparatus comprises a stationary feed array having a plurality of selectably activatable feed array elements, the feed array having a feed array sensitive axis; a reflector, illuminated by the selectably activatable feed array elements; a first mechanism, coupled to the reflector, for varying a position of the reflector along the feed array axis; wherein a desired beam size of the antenna system is selected by varying the reflector position along the feed array sensitive axis and by selectably activating the feed array elements.

Abstract: An antenna comprising a reflector having a reflector surface profile for reflecting a plurality of signals comprising a plurality of communication bands; a multi-depth corrugated horn assembly for receiving the signal comprising the plurality of communication bands; a stepped waveguide coupled to the corrugated horn; a first polarizer coupled to the stepped waveguide for separating a first communication band from the plurality of communication bands; a second polarizer coupled to the stepped waveguide for separating a second communication band from the plurality of communication bands; and a third polarizer coupled to the stepped waveguide for separating a third communication band from the plurality of communication bands. The antenna can simultaneously operate in the K, Ka and EHF frequency bands. Extension of this antenna to include five separate frequency bands is demonstrated.