US3922682A - Aberration correcting subreflectors for toroidal reflector antennas - Google Patents

Aberration correcting subreflectors for toroidal reflector antennas Download PDF

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Publication number
US3922682A
US3922682A US475226A US47522674A US3922682A US 3922682 A US3922682 A US 3922682A US 475226 A US475226 A US 475226A US 47522674 A US47522674 A US 47522674A US 3922682 A US3922682 A US 3922682A
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United States
Prior art keywords
subreflector
antenna system
axis
point
revolution
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Expired - Lifetime
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US475226A
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English (en)
Inventor
Geoffrey Hyde
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Comsat Corp
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Comsat Corp
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Publication date
Application filed by Comsat Corp filed Critical Comsat Corp
Priority to US475226A priority Critical patent/US3922682A/en
Priority to CA226,139A priority patent/CA1039843A/en
Priority to SE7505209A priority patent/SE403855B/xx
Priority to GB18871/75A priority patent/GB1513452A/en
Priority to JP50061158A priority patent/JPS51863A/ja
Priority to DE19752523800 priority patent/DE2523800A1/de
Priority to IT68395/75A priority patent/IT1036133B/it
Priority to NL7506474A priority patent/NL7506474A/xx
Priority to FR7517096A priority patent/FR2275901A1/fr
Application granted granted Critical
Publication of US3922682A publication Critical patent/US3922682A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q19/00—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic
    • H01Q19/10—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using reflecting surfaces
    • H01Q19/18—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using reflecting surfaces having two or more spaced reflecting surfaces
    • H01Q19/19—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using reflecting surfaces having two or more spaced reflecting surfaces comprising one main concave reflecting surface associated with an auxiliary reflecting surface

Definitions

  • ABSTRACT The correction of aberration in toroidal reflector antennas by a novel type of subreflector is disclosed.
  • the specific shape of the subreflector ultimately depends on the geometry of the toroidal reflector
  • the effect of the subreflector is to achieve a point focus in a system which, without the subreflector, does not focus at a point.
  • this is equiva lent to turning a non-planar equiphase surface in the aperture into a plane thereby eliminating the phase error about the aperture plane perpendicular to the desired direction of propagation.
  • the design of the subreflector is accomplished by developing a heuristic geometric optics model of the focusing properties of the toroidal reflector and using a programmable general purpose digital computer to generate the subreflector shape by numerically computing points on the surface of the subreflector for separate, individual rays intercepted by the toroidal reflector, for a bundle of rays incident from the desired direction.
  • the present invention generally relates to toroidal antenna structures and systems, and more particularly to a novel aberration correcting subreflector and design technique useful in both rectangular and non-rectangular toroidal reflector antenna systems.
  • a toroidal reflector may be simply defined as a section of a surface of revolution and, typically, the generating curve is a conic section. If the axis of revolution is perpendicular to the axis of the generating curve, then the reflector is a section of a rectangular torus, otherwise it is a section of a non-rectangular torus, otherwise it is a section of a non-rectangular torus.
  • An example of the latter is the subject of US. Pat. No. 3,852,763 by Kreutel and Hyde entitled "Torus- Type Antenna Having a Conical Scan Capability.
  • toroidal reflector focuses In order to treat the aberration problem in toroidal antennas, and particularly those having parabolas as generating curves, it is useful to first understand how the toroidal reflector focuses.
  • One approach to this is to consider separately the focusing properties of the generating section and the circular arc about which the generating section is swung, and then to consider the interaction of the two.
  • a parabolic reflector has perfect focusing properties for axial rays. However, for rays incident slightly non-parallel to the axis, the focus moves in a direction opposite to the deviation from parallel by the incidnet rays to describe a locus of points which define a best" focus arc. This are is itself a parabola of focal length one-half that of the parabolicsection of the reflector. As the deviation angle to parallel increases, the focus spreads in a coma-like manner. This is manifested in the far-field pattern by gain loss and by the characteristic coma-lobe on the off-side and a reduced sidelobe on the near side of the off-axis beam of incident rays.
  • the resultant focal region may be characterized as having the possibility that more than one ray passes through a given point. More specifically, in the multiple ray regions, i.e. the region bounded by the marginal rays, the caustic surface and the paraxial focus, more than one ray may pass through a given point.
  • the essential points here are the presence of spherical aberration and the incident angle independence of the focal region distribution.
  • the circular section Unlike the parabolic section, which has perfect focusing for rays paral- 2 lel to the section axis and imperfect focusing for a collimated bundle of rays that are not parallel to the axis, the circular section always has abberration for all directions of the ray bundle. But whereas the aberrations for the parabolic section are a function of the deviation angle, the aberrations arising from a circular section are not a function of direction.
  • the optimum location of the focal point of the parabolic section is located inside the location of the paraxial focus of the circular section.
  • the optimum feed position turns out to be located just inside the focal point of the parabolic section, with the refocused configuration giving less pathlength variation in the aperture plane than that encountered by putting the feed at the focal point.
  • a correcting subreflector which, when illuminated by a feed-horn, reflects energy onto the main toroidal reflector so that a beam is formed to radiate in the desired direction.
  • incoming rays incident upon the main reflector are reflected onto the subreflector and from it onto the feed-horn, focusing at a point so that the pathlength from a reference plane is equal for all rays.
  • the specific shape of the correcting subreflector depends on the specific geometry of the main toroidal refelctor, the actual design of the subreflector is achieved by numerical computation of points on the surface of the subreflector for the constraints that (1 all rays focus at a single point, and (2) all pathlengths from a reference plane to the point of focus are constant and equal to a desired reference pathlength.
  • FIG. 1 is a pictorial view illustrating the geometry of a torus antenna
  • FIGS. 2A and 2B are graphs showing efficiency as a function of antenna diameter in wavelengths with illamination as a parameter for two choices of torus ge 3 ometry;
  • FIGS. 3A and 3B are graphs showing parabolic torus gain as a function of antenna diameter in wavelengths with illumination as a parameter for the two choices of torus geometry adopted in FIGS. 2A and 2B, respectively', FIGS. 2A, 28, 3A, and 38 clearly demonstrating the deleterious effects of aberration for electrically larger antennas (larger D/A);
  • FIG. 4 illustrates the basic geometric model used to design the surface of the correcting subreflector according to the invention
  • FIG. 5 illustrates another geometric model representing the vector equations which define points on the surface of the subreflector according to the invention
  • FIGS. 6A, 6B and 6C are, respectively, a plan view and side views of two mutually perpendicular axes of a specific subreflector shape made in accordance with the teaching of the invention.
  • FIGS. 7A and 7B are, respectively, a plan view and a side view of another specific subreflector, herein referred to as a Cassegorian subreflector, made by careful choice of geometric parameters in accordance with the teaching of the invention.
  • FIGS. 8A and 8B show typical approximate crosssections of the Cassegorian subreflector shown in FIGS. 7A and 78.
  • FIG. 1 there is illustrated the geometry of a typical frontfed toroidal reflector.
  • the specific reflector illustrated is non-rectangular in that a 95.5, where a is the angle the axis of revolution 2' makes with the desired direction of propagation z.
  • This geometry produces a conical scan surface which closely approximates the actual conical surface subtended by an earth station site within the continental and contiguous United States and the geostationary are as explained in the aforementioned US. Pat. No. 3,852,763.
  • d is the vertical distance below the toroidal reflector of a feedhorn and D is the vertical dimension of the toroidal reflector
  • 3 s RID s 2 where R is the radius of revolution
  • 0.48 sf/R s 0.49 where f is the focal length of the parabolic generating section.
  • 0, is defined as the field-of-view angle at the antenna.
  • the section M through the vertex V, while typically a parabola, may be any other conic section such as a circle, ellipse or hyperbola.
  • the reflector is formed by rotating the section M about the z axis.
  • the axis of the section M is the z axis, which is the desired direction of the beam formed in the region A,,.
  • the optimum projected location of the focal point F of the parabolic section M is located inside the location of the paraxial focus, P.
  • the optimum feed position turns out to be located just inside the focal point F, the refocused 4 configuration giving less rms pathlength variation in the aperture plane than that encountered by putting the feed at the focal point.
  • the reflector presents the same shape to, and hence has the same beam forming capability for identical feeds located at all points on the are described by the rotation of the feed point of the generating curve about the axis of rotation.
  • a single moveable feed or a plurality of selectively energizable feeds located along the feed are, when illuminating the reflector surface, will form identical beams, the torus of whose axes of beam direction describe the surface of a right circular cone.
  • the result of this feed positioning is to achieve the best point focus in a system which really does not focus at a point.
  • the specific purpose of the invention is to turn the equiphase surface mentioned above into a plane while preserving the field of view of the antenna system.
  • the crux of the problem solved by the invention is that the nonplanar equiphase surface characteristic of the point-fed uncorrected torus is invariant in terms of the physical measurements of the system, while wavelength changes inversely with frequency.
  • a fixed pathlength departure from the planar condition turns into a phase error that increases with frequency.
  • FIGS. 2A and 2B and FIGS. 3A and 3B in terms of efficiency and gain, respectively, as functions of wavelength-normalized antenna diameter D/A for two choices of R/D.
  • D/)t 150 there is little seen of the effects of aberration, while for D/It 300, it is clear that aberration dominates.
  • Equation (1) tells us we can find the unit normal ii... to the surface M.
  • Equation (2) says that if we know this unit normal, and the direction of the incident ray, which is given, we can find the direction of the ray reflected from the surface M, but we do not know its length
  • Equation (4) tells us that since we know H, the desired focal point, and M... the incident point, we know the plane of the two ray segments the first of whic his reflected off M at M. and incident on S at S., i.e., M.S., and the second segmerigf which is the reflection off S at S. towards H, i.e.. 8.11..
  • An implicit condition is that only one ray is incident on S at each point 8..
  • the point H is arbitrary and must i... M.H c. c, 2c, (3, 3,. and
  • sinc fl is a unit vector.
  • Equation (50) is calculated using Equation (50). and the point on the subreflector is now completely established.
  • Equation (7) if we examine this equation geometrically as shown in FIG. 5, the simplicity of the scheme is self-evident.
  • lf 1. is the reference pathlength, then 1.,
  • Equation flu Equation flu
  • HE. and ii are parallel (or antiparallel).
  • A.M., ii and M.E. lie in the same plane. by the laws of geometric optics.
  • M.S., R, and S.H lie in the same plane.
  • the AHS.E. is isoceles and the equal angles e are equal to the angles of incidence and reflection at S..
  • a single moveable feed assembly consisting of a horn. H, and subreflector S, or a plurality of such feed assemblies located along an are about the axis of rotation, z'. of the main reflector will form identical beams. Moreover, each such feed assembly will provide aberration free beams in scanning.
  • FIGS. 6A, 6B and 6C show a specific subreflector designed according to the invention for a non-rectangular toroidal antenna system having a 10-foot aperture and dimensional ratios of flit- 0.487 and RID 2.
  • This subreflector is hyperbolic along the x-axis (the axis of symmetry) and departs from this off the x-axis.
  • this subreflector improved the gain of the antenna system achieved by conventional means by 2dB, from 54dB to S6dB, and the efficiency from about 28% to about 45% aperture efficiency.
  • FIGS. 6A. 6B and 6C While the improvements realized with the subreflector shown in FIGS. 6A. 6B and 6C are significant, by changing the dimensional parameters of the main toroidal reflector. a more optimum antenna configuration can be realized which achieves an aperture efficiency in excess of 70%.
  • a Cassegorian subreflector results for the design procedure according to the invention. Such a subreflector is shown in FIGS. 7A and 7B.
  • the name Cassegorian" was coined because the subreflector has cross-sectional shapes which resemble a subreflector having a hyper bolic section shown in FIG.
  • the new feed method according to the invention corrects pathlength so that true optical focusing is obtained, there is not aberration in the antenna system, and the efficiency is independent of frequency. This permits the development of antennas which have high efficiency independent of frequency.
  • a toroidal reflector antenna system can be designed for use at 4, 6, l2, I4, and GHz by use of appropriate feedhorns, without changing the optics of the system.
  • a toroidal reflector antenna system including a main reflector having the shape of a surface section of a torus of revolution and a feed-horn assembly positioned to illuminate said main reflector and thereby form beams in the desired directions of propagation, the improvement comprising an aberration correcting subreflector interposed between said main reflector and said feed-horn and forming a feed assembly with said feed-horn, the surface of said subreflector being nonconcentric with said main reflector and so designed that for the aberration correcting surface of said subreflector only one ray is incident on the surface at each point thereon, substantially all rays focus at a single point at said feed-horn and substantially all ray pathlengths from a reference aperture plane to said single point of focus are constant and equal to a predetermined reference pathlength, whereby said system is free of aberration and the efficiency of said system is independent of frequency, said feed assembly further being movable along an are about the axis of revolution of said main reflector to provide substantially aberration free beams in scanning.
  • main reflector is a surface section of a nonrectangular torus, said antenna system having a conical scan capability to scan along the geostationary arc.

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US475226A 1974-05-31 1974-05-31 Aberration correcting subreflectors for toroidal reflector antennas Expired - Lifetime US3922682A (en)

Priority Applications (9)

Application Number Priority Date Filing Date Title
US475226A US3922682A (en) 1974-05-31 1974-05-31 Aberration correcting subreflectors for toroidal reflector antennas
CA226,139A CA1039843A (en) 1974-05-31 1975-05-02 Aberration correcting subreflectors for toroidal reflector antennas
GB18871/75A GB1513452A (en) 1974-05-31 1975-05-06 Subreflectors for toroidal reflector antennas
SE7505209A SE403855B (sv) 1974-05-31 1975-05-06 Toroidreflektorantennanordning med organ for minskning av aberration
JP50061158A JPS51863A (en) 1974-05-31 1975-05-23 Toroidaru rifurekuta antenayo shusahoseiyohojorifurekuta
DE19752523800 DE2523800A1 (de) 1974-05-31 1975-05-28 Ringreflektorantenne mit unterreflektor zur aberrationskorrektur
IT68395/75A IT1036133B (it) 1974-05-31 1975-05-30 Subriflettore corraettore di aberrazioni per antenne a riflettore toroidale
NL7506474A NL7506474A (nl) 1974-05-31 1975-05-30 Aberratie corrigerende hulpreflectoren voor toro- idale reflectorantennes.
FR7517096A FR2275901A1 (fr) 1974-05-31 1975-06-02 Sous-reflecteur de correction d'aberrations d'antenne toroidale

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US475226A US3922682A (en) 1974-05-31 1974-05-31 Aberration correcting subreflectors for toroidal reflector antennas

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US (1) US3922682A (de)
JP (1) JPS51863A (de)
CA (1) CA1039843A (de)
DE (1) DE2523800A1 (de)
FR (1) FR2275901A1 (de)
GB (1) GB1513452A (de)
IT (1) IT1036133B (de)
NL (1) NL7506474A (de)
SE (1) SE403855B (de)

Cited By (34)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
USD244096S (en) * 1976-01-07 1977-04-19 Mecaniplast Plate-type antenna
US4145695A (en) * 1977-03-01 1979-03-20 Bell Telephone Laboratories, Incorporated Launcher reflectors for correcting for astigmatism in off-axis fed reflector antennas
US4201992A (en) * 1978-04-20 1980-05-06 Communications Satellite Corporation Multibeam communications satellite
US4272769A (en) * 1979-08-27 1981-06-09 Young Frederick A Microwave antenna with parabolic main reflector
US4339757A (en) * 1980-11-24 1982-07-13 Bell Telephone Laboratories, Incorporated Broadband astigmatic feed arrangement for an antenna
US4343004A (en) * 1980-11-24 1982-08-03 Bell Telephone Laboratories, Incorporated Broadband astigmatic feed arrangement for an antenna
US4355314A (en) * 1980-11-28 1982-10-19 Bell Telephone Laboratories, Incorporated Wide-field-of-view antenna arrangement
DE3302727A1 (de) * 1982-02-15 1983-09-01 Kokusai Denshin Denwa K.K., Tokyo Wellenleiter-strahlzufuehrung
US4482898A (en) * 1982-10-12 1984-11-13 At&T Bell Laboratories Antenna feed arrangement for correcting for astigmatism
US4491848A (en) * 1982-08-30 1985-01-01 At&T Bell Laboratories Substantially frequency-independent aberration correcting antenna arrangement
US4535338A (en) * 1982-05-10 1985-08-13 At&T Bell Laboratories Multibeam antenna arrangement
US4631545A (en) * 1984-11-16 1986-12-23 At&T Bell Laboratories Antenna arrangement capable of astigmatism correction
US4638322A (en) * 1984-02-14 1987-01-20 The Boeing Company Multiple feed antenna
US4786910A (en) * 1987-11-05 1988-11-22 American Telephone And Telegraph Company, At&T Bell Laboratories Single reflector multibeam antenna arrangement with a wide field of view
US4833484A (en) * 1984-02-09 1989-05-23 The General Electric Company, P.L.C. Earth terminal for satellite communication
EP0168904B1 (de) * 1984-02-24 1992-06-17 Nippon Telegraph And Telephone Corporation Asymmetrische Spiegelantenne mit zwei Reflektoren
US5175562A (en) * 1989-06-23 1992-12-29 Northeastern University High aperture-efficient, wide-angle scanning offset reflector antenna
USD387773S (en) * 1996-10-28 1997-12-16 Weller Roger G Satellite dish protective visor
WO2002005385A1 (en) * 2000-07-10 2002-01-17 Wavefrontier Co., Ltd Reflector antenna
US20020113744A1 (en) * 2001-02-22 2002-08-22 Strickland Peter C. Low sidelobe contiguous-parabolic reflector array
WO2007136293A1 (en) * 2006-05-23 2007-11-29 Intel Corporation Millimeter-wave reflector antenna system and methods for communicating using millimeter-wave signals
US20070287384A1 (en) * 2006-06-13 2007-12-13 Sadri Ali S Wireless device with directional antennas for use in millimeter-wave peer-to-peer networks and methods for adaptive beam steering
US20080094298A1 (en) * 2006-10-23 2008-04-24 Harris Corporation Antenna with Shaped Asymmetric Main Reflector and Subreflector with Asymmetric Waveguide Feed
US20100033390A1 (en) * 2006-05-23 2010-02-11 Alamouti Siavash M Millimeter-wave communication system with directional antenna and one or more millimeter-wave reflectors
US20140055314A1 (en) * 2012-08-21 2014-02-27 Northeastern University Doubly shaped reflector transmitting antenna for millimeter-wave security scanning system
EP2637253A4 (de) * 2011-12-29 2014-12-17 Quantrill Estate Inc Universelle vorrichtung für energiekonzentration
USD738866S1 (en) * 2013-09-25 2015-09-15 World Products Llc Antenna with dome form factor
EP2871716A4 (de) * 2012-07-03 2016-03-09 Kuang Chi Innovative Tech Ltd Antennenreflektorphasenkorrekturfilm und reflektorantenne
RU2629906C1 (ru) * 2016-11-09 2017-09-04 Самсунг Электроникс Ко., Лтд. Зеркальная антенна с двойной поляризацией и широким углом сканирования
US9874508B2 (en) * 2013-08-19 2018-01-23 Iasotek, Llc. Spectrophotometer based on optical caustics
USD814449S1 (en) * 2016-02-19 2018-04-03 Samsung Electronics Co., Ltd. Network terminal
USD815075S1 (en) * 2016-02-19 2018-04-10 Samsung Electronics Co., Ltd. Network terminal
US11101569B2 (en) * 2020-01-08 2021-08-24 Dau-Chyrh Chang Toroidal compact antenna test range
RU2776722C1 (ru) * 2021-06-29 2022-07-26 Федеральное государственное казенное образовательное учреждение высшего образования "Академия Федеральной службы безопасности Российской Федерации" (Академия ФСБ России) Осесимметричная многодиапазонная многолучевая многозеркальная антенна

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5698905A (en) * 1980-01-11 1981-08-08 Kokusai Denshin Denwa Co Ltd <Kdd> Dual reflecting mirror antenna
JPS57178402A (en) * 1981-04-27 1982-11-02 Kokusai Denshin Denwa Co Ltd <Kdd> Multireflex mirror antenna
GB2154067B (en) * 1984-02-09 1988-02-17 Gen Electric Plc An earth terminal for satellite communication systems
US4806985A (en) * 1986-07-11 1989-02-21 Xerox Corporation Stripper fingers

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3737909A (en) * 1970-06-18 1973-06-05 Radiation Inc Parabolic antenna system having high-illumination and spillover efficiencies
US3828352A (en) * 1971-08-09 1974-08-06 Thomson Csf Antenna system employing toroidal reflectors
US3852763A (en) * 1970-06-08 1974-12-03 Communications Satellite Corp Torus-type antenna having a conical scan capability

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3852763A (en) * 1970-06-08 1974-12-03 Communications Satellite Corp Torus-type antenna having a conical scan capability
US3737909A (en) * 1970-06-18 1973-06-05 Radiation Inc Parabolic antenna system having high-illumination and spillover efficiencies
US3828352A (en) * 1971-08-09 1974-08-06 Thomson Csf Antenna system employing toroidal reflectors

Cited By (42)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
USD244096S (en) * 1976-01-07 1977-04-19 Mecaniplast Plate-type antenna
US4145695A (en) * 1977-03-01 1979-03-20 Bell Telephone Laboratories, Incorporated Launcher reflectors for correcting for astigmatism in off-axis fed reflector antennas
US4201992A (en) * 1978-04-20 1980-05-06 Communications Satellite Corporation Multibeam communications satellite
US4272769A (en) * 1979-08-27 1981-06-09 Young Frederick A Microwave antenna with parabolic main reflector
US4339757A (en) * 1980-11-24 1982-07-13 Bell Telephone Laboratories, Incorporated Broadband astigmatic feed arrangement for an antenna
US4343004A (en) * 1980-11-24 1982-08-03 Bell Telephone Laboratories, Incorporated Broadband astigmatic feed arrangement for an antenna
US4355314A (en) * 1980-11-28 1982-10-19 Bell Telephone Laboratories, Incorporated Wide-field-of-view antenna arrangement
DE3302727A1 (de) * 1982-02-15 1983-09-01 Kokusai Denshin Denwa K.K., Tokyo Wellenleiter-strahlzufuehrung
US4535338A (en) * 1982-05-10 1985-08-13 At&T Bell Laboratories Multibeam antenna arrangement
US4491848A (en) * 1982-08-30 1985-01-01 At&T Bell Laboratories Substantially frequency-independent aberration correcting antenna arrangement
US4482898A (en) * 1982-10-12 1984-11-13 At&T Bell Laboratories Antenna feed arrangement for correcting for astigmatism
US4833484A (en) * 1984-02-09 1989-05-23 The General Electric Company, P.L.C. Earth terminal for satellite communication
US4638322A (en) * 1984-02-14 1987-01-20 The Boeing Company Multiple feed antenna
EP0168904B1 (de) * 1984-02-24 1992-06-17 Nippon Telegraph And Telephone Corporation Asymmetrische Spiegelantenne mit zwei Reflektoren
US4631545A (en) * 1984-11-16 1986-12-23 At&T Bell Laboratories Antenna arrangement capable of astigmatism correction
US4786910A (en) * 1987-11-05 1988-11-22 American Telephone And Telegraph Company, At&T Bell Laboratories Single reflector multibeam antenna arrangement with a wide field of view
US5175562A (en) * 1989-06-23 1992-12-29 Northeastern University High aperture-efficient, wide-angle scanning offset reflector antenna
USD387773S (en) * 1996-10-28 1997-12-16 Weller Roger G Satellite dish protective visor
WO2002005385A1 (en) * 2000-07-10 2002-01-17 Wavefrontier Co., Ltd Reflector antenna
US6563473B2 (en) * 2001-02-22 2003-05-13 Ems Technologies Canada, Ltd. Low sidelobe contiguous-parabolic reflector array
US20020113744A1 (en) * 2001-02-22 2002-08-22 Strickland Peter C. Low sidelobe contiguous-parabolic reflector array
WO2007136293A1 (en) * 2006-05-23 2007-11-29 Intel Corporation Millimeter-wave reflector antenna system and methods for communicating using millimeter-wave signals
US20100033390A1 (en) * 2006-05-23 2010-02-11 Alamouti Siavash M Millimeter-wave communication system with directional antenna and one or more millimeter-wave reflectors
US20100156721A1 (en) * 2006-05-23 2010-06-24 Alamouti Siavash M Millimeter-wave indoor wireless personal area network with ceiling reflector and methods for communicating using millimeter-waves
US8149178B2 (en) 2006-05-23 2012-04-03 Intel Corporation Millimeter-wave communication system with directional antenna and one or more millimeter-wave reflectors
US8193994B2 (en) 2006-05-23 2012-06-05 Intel Corporation Millimeter-wave chip-lens array antenna systems for wireless networks
US8395558B2 (en) 2006-05-23 2013-03-12 Intel Corporation Millimeter-wave reflector antenna system and methods for communicating using millimeter-wave signals
US20070287384A1 (en) * 2006-06-13 2007-12-13 Sadri Ali S Wireless device with directional antennas for use in millimeter-wave peer-to-peer networks and methods for adaptive beam steering
US8320942B2 (en) 2006-06-13 2012-11-27 Intel Corporation Wireless device with directional antennas for use in millimeter-wave peer-to-peer networks and methods for adaptive beam steering
US20080094298A1 (en) * 2006-10-23 2008-04-24 Harris Corporation Antenna with Shaped Asymmetric Main Reflector and Subreflector with Asymmetric Waveguide Feed
EP2637253A4 (de) * 2011-12-29 2014-12-17 Quantrill Estate Inc Universelle vorrichtung für energiekonzentration
US9825370B2 (en) 2012-07-03 2017-11-21 Kuang-Chi Innovative Technology Ltd. Antenna reflector phase correction film and reflector antenna
EP2871716A4 (de) * 2012-07-03 2016-03-09 Kuang Chi Innovative Tech Ltd Antennenreflektorphasenkorrekturfilm und reflektorantenne
US20140055314A1 (en) * 2012-08-21 2014-02-27 Northeastern University Doubly shaped reflector transmitting antenna for millimeter-wave security scanning system
US9874508B2 (en) * 2013-08-19 2018-01-23 Iasotek, Llc. Spectrophotometer based on optical caustics
USD738866S1 (en) * 2013-09-25 2015-09-15 World Products Llc Antenna with dome form factor
USD814449S1 (en) * 2016-02-19 2018-04-03 Samsung Electronics Co., Ltd. Network terminal
USD815075S1 (en) * 2016-02-19 2018-04-10 Samsung Electronics Co., Ltd. Network terminal
RU2629906C1 (ru) * 2016-11-09 2017-09-04 Самсунг Электроникс Ко., Лтд. Зеркальная антенна с двойной поляризацией и широким углом сканирования
US11101569B2 (en) * 2020-01-08 2021-08-24 Dau-Chyrh Chang Toroidal compact antenna test range
RU2776722C1 (ru) * 2021-06-29 2022-07-26 Федеральное государственное казенное образовательное учреждение высшего образования "Академия Федеральной службы безопасности Российской Федерации" (Академия ФСБ России) Осесимметричная многодиапазонная многолучевая многозеркальная антенна
RU2805200C1 (ru) * 2023-01-18 2023-10-12 Федеральное государственное казенное образовательное учреждение высшего образования "Академия Федеральной службы безопасности Российской Федерации" (Академия ФСБ России) Составная многолучевая зеркальная антенна

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DE2523800A1 (de) 1975-12-11
GB1513452A (en) 1978-06-07
JPS51863A (en) 1976-01-07
NL7506474A (nl) 1975-12-02
CA1039843A (en) 1978-10-03
SE403855B (sv) 1978-09-04
SE7505209L (sv) 1975-12-01
FR2275901A1 (fr) 1976-01-16
IT1036133B (it) 1979-10-30

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