Antenna With Parasitic Reflector Patents (Class 343/834)
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Patent number: 6320544Abstract: The method of producing antennas and antenna arrays with desired beam widths applies to both single and dual polarization antennas, and controls and modifies the radiation patterns of the antenna's radiating elements by placing appropriately designed parasitic elements in their vicinity.Type: GrantFiled: April 6, 2000Date of Patent: November 20, 2001Assignee: Lucent Technologies Inc.Inventors: Ilya A. Korisch, Benjamin Rulf
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Patent number: 6310585Abstract: An antenna arrangement is provide with a variable parasitic element whose position is varied as a function of the scan angle. According to an exemplary embodiment of the invention, a variable scanning array dual polarized antenna provides different scan angles by varying phase elements of the array. According to this embodiment an adjustable phase shift mechanism is used to modify the phase of the antenna array. The adjustable phase shift mechanism is used changes the antenna's phase as a function of a moveable dielectric slab. The dielectric slab slides over a microstrip line that results in a phase change that is a function of line coverage. A parasitic element is also connected to the dielectric slab such that the position of the parasitic element is varied in response to a change in the phase shift mechanism thereby varying the canceling signal of the parasitic element to optimize port isolation for the dual polarized antenna.Type: GrantFiled: September 29, 1999Date of Patent: October 30, 2001Assignee: Radio Frequency Systems, Inc.Inventor: Ronald A. Marino
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Publication number: 20010024176Abstract: A modified offset parabolic antenna is disclosed which provides improved gain when receiving satellite broadcasts from geosynchronous transmission sources spaced substantially 10 degrees apart. The surface of the reflector is defined by a Zernike expansion mapped to a unit circle. The values of the parameters of the Zernike expansion are selected to provide a shaped reflector surface which focuses beams from the three separate sources onto three focal points such that the gain of the antenna is maximized. A peak beam gain for an offset beam of substantially 33.9 dBi has been achieved.Type: ApplicationFiled: February 5, 2001Publication date: September 27, 2001Applicant: CHANNEL MASTER LLCInventors: Scott J. Cook, Bruce W. Barratt
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Patent number: 6278413Abstract: An antenna structure including a driven antenna element is formed on a substrate that is folded to provide a closed surface, causing the substrate to be nonplanar and spacing the driven antenna element from a base of the substrate. Adhesives on an outside surface of the substrate permit fastening of the folded substrate to a container or packaging. The substrate may have one or more resilient elbows formed by folding, to bias the antenna element carrying portion of the substrate from the base of the substrate. A modulation circuit may drive the driven antenna element. The flexible substrate may be folded into any of a variety of forms such as a substantially O-shape, a substantially oval shape, a substantially coil shape, a substantially spiral shape, and a substantially S-shape. Additional folds in the substrate may provide surfaces for mounting passive or parasitic antenna elements, such as reflectors and directors, to form a Yagi antenna structure.Type: GrantFiled: March 29, 1999Date of Patent: August 21, 2001Assignee: Intermec IP CorporationInventors: Steven C. Hugh, Christopher A. Wiklof, Terry M. Hudkins
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Patent number: 6222490Abstract: A fishbone-shaped patch antenna structure is provided to increase half-power beamwidth in the horizontal plane of slot coupled microstrip patch antenna containing limited ground plate and limited reflector. This effect is obtained by designing the resonant member to have a toothed portion along either edge of resonant axis thereof.Type: GrantFiled: April 4, 2000Date of Patent: April 24, 2001Assignee: SmartAnt Telecomm Co., Ltd.Inventors: Song Jia-Jiu, Wu Hung-Chang
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Patent number: 6191751Abstract: A multi-element radio antenna assembly is described. The antenna assembly includes a ground plane element having an array of conductor elements disposed thereon. A pair of LC trap structures provide dual band resonance for cellular telephone and PCS device bandwidth ranges. Additional performance may be achieved with parasitic reflector and director elements. The multi-element directional antenna finds particular applicability for in-vehicle use.Type: GrantFiled: May 1, 1999Date of Patent: February 20, 2001Assignee: RangeStar Wireless, Inc.Inventor: Greg Johnson
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Patent number: 6154180Abstract: A parasitic antenna array (Yagi-Uda or loop type) for multiple frequency bands has its driven and parasitic elements interlaced on a single support boom. In a first aspect of the invention, series resonant circuits are located in one or more parasitic director elements in order to minimize the deleterious mutual coupling effect between directors of different frequency bands. In a second aspect of the invention, an inductance is placed across the feed point of the driven element of one or more non-selected frequency bands in order to minimize the bandwidth narrowing effect of closely-spaced driven elements and to provide a desired feed point impedance at the driven element of the selected frequency band. Although the two aspects of the invention may be used without one another, they are advantageously employed together. In addition, the second aspect of the invention may be applied to closely-spaced driven elements that are not part of a parasitic array.Type: GrantFiled: September 3, 1998Date of Patent: November 28, 2000Inventor: David E. Padrick
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Patent number: 6144345Abstract: For use in or with a satellite receiving system having a receiving element such as low noise amplifier, a selectively variable RF signal attenuator locatable between the satellite and the amplifier comprises an RF radiation shield having at least one selectively variable radiation-passing area. The radiation shield comprises a plurality of overlapped shield members having selectively overlapped openings, movement of one member relative to the other causing the effective intersection defining a radiation-passing area of the shield to vary. According to a disclosed method, after locating a radiation attenuator as described between the satellite and the amplifier, the signal received from the satellite is variably attenuated using the signal attenuator until the signal level of the received radiation is within a range of an associated signal indicator wherein the indicator's response is more linear than it is at higher signal levels.Type: GrantFiled: September 4, 1996Date of Patent: November 7, 2000Assignee: Hughes Electronics CorporationInventor: David J. Kuether
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Patent number: 6140965Abstract: A patch antenna having enhanced frequency response has a generally planar element formed of a substantially conductive material, and antenna feed conductor electrically connected to the antenna element, and a generally planar parasitic element formed of a substantially conductive material positioned substantially coaxially with respect to the antenna element and spaced apart therefrom. The distance by which the parasitic element is spaced apart from the antenna element in order to provide such enhanced frequency response of the patch antenna is determined empirically. An optimally configured array of such patch antennas is also disclosed.Type: GrantFiled: May 6, 1998Date of Patent: October 31, 2000Assignee: Northrop Grumman CorporationInventor: Allen Lee Van Hoozen
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Patent number: 6114999Abstract: An antenna device for a Mobile Phone is disclosed, wherein a distance between a miniaturized radiator and a miniaturized reflector may be shortened by means of an introduced dielectric material optimizing the electrical distance between the radiator and reflector to create a compact antenna unit having a desired cardioid shaped radiation pattern. Furthermore an additional field reducing means in the form of metallic strips is used, for example utilizing an additional dielectric layer, with at least two thin isolated metallic strips running parallel to the current edges of the reflector element to thereby form chokes at the back of the reflector, which is normally directed towards the user, to further concentrate the near-field on this side to an area in between the chokes.Type: GrantFiled: October 30, 1997Date of Patent: September 5, 2000Assignee: Telefonaktiebolaget LM EricssonInventors: Erland Cassel, Jan Cassel
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Patent number: 6104348Abstract: An antenna device for receiving and/or transmitting dual polarized electromagnetic waves, comprising at least one antenna element (7). There are disposed parasitic elements (8, 9) of an electrically conductive material in a region, which surrounds the antenna element and includes the space between and including two parallel planes (2, 1) being defined by a ground plane layer (2) and the antenna element (7), respectively. Each parasitic element (8, 9) comprises at least one elongated, longitudinal portion, extending along an associated lateral side of the antenna element.Type: GrantFiled: July 23, 1998Date of Patent: August 15, 2000Assignee: Allgon ABInventors: Jan-Erik Karlsson, Stefan Jonsson
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Patent number: 6046705Abstract: A standing wave plasma antenna is provided. An ionizer generates an ioniz beam in a bounded plasma column extending along a vertical axis. A modulating signal is applied to an electro-optical crystal that modulates the ionizing beam. The resulting changes in the ionizing beam produce gradients in the plasma that cause ions and electrons to oscillate in a vertical path that generates alternating current having the frequency of the modulator. At a remote end the antenna terminates in a reflector. The reflector includes a chamber having a plasma with a charged particle density that is greater than the charged particle density in the plasma. The generated currents are therefore reflected as in a standing wave antenna. These currents generate an amplitude-, phase- or frequency-modulated electromagnetic field that radiates from the plasma column.Type: GrantFiled: May 21, 1999Date of Patent: April 4, 2000Assignee: The United States of America as represented by the Secretary of the NavyInventor: Theodore R. Anderson
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Patent number: 6034641Abstract: An antenna device comprises an array antenna having a plurality of transmitting planar antenna elements and a plurality of receiving planar antenna elements, a transmission selecting circuit for selecting at least one of the transmitting planar antenna elements, a transmitting circuit for transmitting a signal to the selected at least one transmitting planar antenna element, a reception selecting circuit for selecting at least one of the receiving planar antenna elements, and a receiving circuit for receiving a signal from the selected at least one receiving antenna element. By selecting the planar antenna elements exclusively for transmission or reception, it becomes possible to radiate or absorb (receive) a main beam in or from a direction corresponding to the respective planar antenna element, thereby enabling more minute switching of the main beam directions and improving the directional resolution of the antenna device.Type: GrantFiled: September 16, 1997Date of Patent: March 7, 2000Assignee: Honda Giken Kogyo Kabushiki KaishaInventors: Hiroshi Kudoh, Jun Ashihara
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Patent number: 5999142Abstract: A first antenna configuration contemplates a body housing and an antenna cap positioned at a top portion of the body housing. A helical winding is disposed within the antenna cap for radiating electromagnetic waves. A reflecting plate is installed within the antenna cap at a spaced-apart distance from the helical winding for reflecting the electromagnetic waves in a direction away from a user. Polyacetal material is disposed within the antenna cap for supporting the reflecting plate.Type: GrantFiled: May 23, 1996Date of Patent: December 7, 1999Assignee: SamSung Electronics Co., Ltd.Inventor: Chang-Weon Jang
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Patent number: 5977914Abstract: The microstrip antenna of the present invention has a basic structure of a ground conductor plate, dielectric substrate and radiation conductor plate laminated together. On the dielectric substrate, upon which the radiation conductor plate is formed, two radio wave reflectors are placed parallel to each other facing across the radiation conductor plate. The two surfaces of the two radio wave reflectors that are facing each other are either perpendicular to the dielectric substrate, or else the interval between the two surfaces enlarges as they depart from the dielectric substrate. Due to this structure, by increasing the variation in antenna directivity, the antenna can be made less susceptible to noise generated from noise sources in the antenna vicinity. Moreover, the antenna can be small-sized since the radio wave reflectors can be placed close to the radiation conductor plate.Type: GrantFiled: May 13, 1997Date of Patent: November 2, 1999Assignee: NEC CorporationInventor: Nobuya Harano
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Patent number: 5969691Abstract: The present invention provides a fuel dispenser antenna configuration having an antenna with a directive radiation pattern for receiving or transmitting electromagnetic energy, and a reflective surface on the fuel dispenser housing for redirecting the directive radiation pattern of the antenna so that the directive radiation pattern reflects off of the reflective surface and extends in a second direction over a fueling position.Type: GrantFiled: February 10, 1998Date of Patent: October 19, 1999Assignee: Gilbarco Inc.Inventor: Howard M. Myers
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Patent number: 5969685Abstract: Multiple frequency band antennas are pivotally connected to electronic devices such that coaxial connectors are not required. A dielectric substrate, including a plurality of radiating elements disposed thereon, is pivotally connected to an electronic device housing so as to have a predetermined path of rotation from a first position to a second position. At least one of the radiating elements disposed on the dielectric substrate is maintained in a substantially constant spaced-apart relationship with a conductive element disposed within the housing throughout the predetermined path so as to be capacitively coupled with the conductive element.Type: GrantFiled: August 17, 1998Date of Patent: October 19, 1999Assignee: Ericsson Inc.Inventors: Gerard James Hayes, Kim Rutkowski, Charles Rudisill, Russell Evans Winstead
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Patent number: 5905473Abstract: A passive reflective antenna located near an active receiving antennas is used to change the energy at the receiving antenna. The change in energy may be such as to remove a null created by multipath or to provide directionality, or both. The receiving antennas is permanently connected to a single receiver. When the receiver's output signal degrades below an acceptable level of quality, the reflective phase of the passive antenna's load is changed to change the phase of the reflected energy and achieve a desired effect (remove a null, change directionality, etc.) at the receiving antenna. In the simplest embodiment, the termination of the passive antenna is switched from an open circuit to a short circuit, or vice versa, to invert the phase of the reflected energy. The use of reflective elements in antenna designs, usually to achieve directionality, is well known (see the common Yagi or corner reflector antenna designs, for example), but these use passive reflector elements.Type: GrantFiled: March 31, 1997Date of Patent: May 18, 1999Assignee: ReSound CorporationInventor: Jon C. Taenzer
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Patent number: 5872544Abstract: A 90 degree azimuth beamwidth is achieved in a narrow cellular antenna, by inclusion of sidewalls. To improve front-to-back performance, slot radiating elements extending through the sidewalls re-radiate signals behind the antenna. Signals re-radiated from the slot elements are effective to partially cancel signals otherwise radiated behind the antenna as a result of diffraction. H-shaped slots are described for sidewall use and side-to-side slots are described for endwall use. Slots may be dielectrically loaded by contiguous portions of a radome.Type: GrantFiled: February 4, 1997Date of Patent: February 16, 1999Assignee: GEC-Marconi Hazeltine Corporation Electronic Systems DivisionInventor: Gary A. Schay
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Patent number: 5767807Abstract: A reactively controlled directive antenna array that has a single central monopole or dipole as a radiating element excited directly by a feed system. A plurality of parasitic elements surround the radiating element and through changing the state of the parasitic impedance causing the antenna to be in an omni directional or beam pointing mode according to whether the parasitic elements are open circuited or short circuited. A computer modem and memory including stored programs control the antenna array in an omnidirectional or directive mode to locate, identify and communicate with nodes in a wireless communication network. A stored table is created in the memory indicating the antenna direction for communicating with each node in the network. Using the stored table, the computer initiates a communication sequence with a selected node, the sequence having the advantages of improved signal sensitivity and angular discrimination for wireless communication systems.Type: GrantFiled: June 5, 1996Date of Patent: June 16, 1998Assignee: International Business Machines CorporationInventor: Don Michael Pritchett
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Patent number: 5689262Abstract: Microwave devices incorporate at least one photosensitive baffle that is selectively illuminated, changing the baffle's electronic characteristic from being transparent to microwave energy to being reflective thereof. That action selectively alters an electronic characteristic of the microwave device. The effect is shown applied in a number of devices, including a back lobe antenna. Undesired back lobes occuring at a principal frequency are reduced in a back plane antenna by alternately coupling and decoupling an extension to the antenna's back plane at a rate sufficiently high enough to shift the back lobes to adjacent frequencies. A photoelectrically controlled baffle suitably serves as the extension.Type: GrantFiled: June 26, 1996Date of Patent: November 18, 1997Assignee: McDonnell Douglas CorporationInventor: Jesse Clopton James
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Patent number: 5539419Abstract: An antenna for mobile communication includes a sleeve antenna having a feed point; at least one linear parasitic element insulated electrically form the sleeve antenna; and a supporting means for supporting the sleeve antenna and the linear parasitic element. The supporting means supports the sleeve antenna and the linear parasitic element so that the feed point of the sleeve antenna is located at a different elevation from an elevation of a central point of the linear parasitic element.Type: GrantFiled: October 4, 1995Date of Patent: July 23, 1996Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Koichi Ogawa, Tomoki Uwano
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Patent number: 5497168Abstract: A dielectric material having a dielectric constant which varies inversely with frequency, and preferably with the second power of frequency, fills the space between a radiator and a reflecting groundplane. The back-directed wave is reflected back to the radiator in phase with the directly radiated wave over a wide frequency band, increasing the radiator efficiency.Type: GrantFiled: August 4, 1994Date of Patent: March 5, 1996Assignee: Hughes Aircraft CompanyInventors: Michael D. Thomas, Ronald I. Wolfson, Jerome I. Glaser, Joseph P. Smalanskas, Shane H. Hunter, Allen M. Tran
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Patent number: 5485167Abstract: A multiple layer dipole array that provides for a multi-frequency band phased array antenna. Several layers of dipole pair arrays, each tuned to a different frequency band, are stacked relative to each other along the transmission/reception direction. The highest frequency array is in front of the next lowest frequency array and so forth. Due to the frequency selective property of the arrays, incident high frequency signals are completely absorbed by the highest frequency array. In regard to incident low frequency signals, the insertion loss due to higher frequency arrays is small resulting in good performance of the lower frequency arrays. The multi-frequency band phased array antenna may use active or driven dipole pairs, or parasitic elements that form the multiple layer dipoles. The multiple layer dipole array of the present invention may employ corporate feed circuit boards and a corporate feed power divider, using strip transmission line circuits, for example.Type: GrantFiled: January 18, 1994Date of Patent: January 16, 1996Assignee: Hughes Aircraft CompanyInventors: Nam S. Wong, Kuan M. Lee, Raymond Tang
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Patent number: 5440319Abstract: An antenna/downconverter directed to the subscription television distribution industry. The antenna/downconverter (20) includes an integral multidisc director mounted to a housing (51) which defines a reflector cup (54), side lobe suppression ears (38) and a chamber (66) which provides environmental protection for downconverter electronics (184). Received microwave energy is coupled to the downconverter electronics from the perimeter of a receive disc (50) axially spaced from the reflector cup. The housing defines a plurality of jaws (36) which facilitate alignment to variously polarized microwave signals when an installer receives a mounting mast in a selected one of the jaws.Type: GrantFiled: October 1, 1993Date of Patent: August 8, 1995Assignee: California AmplifierInventors: Joel J. Raymond, Lawrence G. Crawford
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Patent number: 5418545Abstract: A slot fed antenna is disclosed for use in radiating energy. The antenna includes a flat conductive member having an elongated vertically-oriented slot dividing the member into a pair of horizontally-extending variable-length flat dipole wing elements. Each of the flat dipole wing elements has a vertically-extending rectilinear edge. Also, each wing element extends in width in a direction perpendicular to the rectilinear edge from a minimum at its center and at each of its upper and lower ends to a maximum midway between each of the ends and the center.Type: GrantFiled: November 9, 1993Date of Patent: May 23, 1995Assignee: Harris CorporationInventors: Fred A. Pantsios, Theodore S. Hebron, William A. Kerkhoff
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Patent number: 5233362Abstract: An antenna (20) has a set of elongated electrically conductive radiating elements (24) disposed about a central mast (26) in the form of a maypole. The radiating elements are electrically connected to each other at a top end of the mast by a top ring (28) and near a bottom end of the mast by a bottom ring (30), both of the rings being electrically insulated from the mast. A positioning unit (32) is located on the mast between the two rings for bowing the radiating elements away from the mast. Sections of the respective radiating elements located between the positioning unit and the bottom ring are severed and connected together by impedance elements (82). Each of the impedance elements includes a resistor (84) which serves as a load for providing a current distribution in a radiating element similar to that of a traveling wave, the impedance elements also having an inductor (86) and a capacitor (88) connected in parallel with the resistor.Type: GrantFiled: January 28, 1991Date of Patent: August 3, 1993Assignee: Hughes Aircraft CompanyInventors: Eduardo H. Villaseca, Donald G. Keppler
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Patent number: 5231413Abstract: An IFF airborne antenna including a single primary radiating element 20 with a plurality of nuisance elements 30, 40, 50 associated with the primary radiating element is disclosed in conjunction with a switching device for switching respective nuisance elements so as to selectively modify the characteristics pattern of the primary radiating element in order to obtain either an omnidirectional pattern corresponding to the pattern of the IFF surveillance mode or a first directional pattern corresponding to the fore directional pattern in the IFF interrogation mode or a second directional pattern corresponding to the monitoring pattern in the IFF interrogation mode. The switching of the nuisance elements makes it possible to selectively obtain the fore directional pattern corresponding either to a first IFF standard (Western standard) on a first frequency band or to a second IFF standard (Eastern standard) on a second frequency band which is different from the first frequency band.Type: GrantFiled: August 1, 1991Date of Patent: July 27, 1993Assignee: Thomson-CSFInventor: Serge Dubois
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Patent number: 5229783Abstract: There is provided a new and useful field adjustable sectoral antenna comprising a flat reflecting surface having a front surface and first and second sides; at least one radiating element mounted in front of the front surface; and a pair of side panels each having front and rear edges and inner and outer surfaces; and wherein the panels are mounted with their inner surfaces along respective ones of the first and second sides of the reflecting surface for forward and rearward sliding movement of the side panels relative to the reflecting surface.Type: GrantFiled: December 24, 1991Date of Patent: July 20, 1993Inventors: Stephen E. Tilston, David A. Tilston
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Patent number: 5220335Abstract: A directional microstrip antenna includes a driven patch surrounded by an isolated reflector and one or more coplanar directors, all separated from a groundplane on the order of 0.1 wavelength or less to provide endfire beam directivity without requiring power dividers or phase shifters. The antenna may be driven at a feed point a distance from the center of the driven patch in accordance with conventional microstrip antenna design practices for H-plane coupled or horizontally polarized signals. The feed point for E-plane coupled or vertically polarized signals is at a greater distance from the center than the first distance. This feed point is also used for one of the feed signals for circularly polarized signals. The phase shift between signals applied to feed points for circularly polarized signals must be greater than the conventionally required 90.degree. and depends upon the antenna configuration.Type: GrantFiled: February 28, 1991Date of Patent: June 15, 1993Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space AdministrationInventor: John Huang
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Patent number: 5038152Abstract: A broad band omnidirectional monocone antenna 10 having a wide operative frequency spectrum and a large elevation angle A is disclosed herein. The antenna 10 of the present invention includes an input circular waveguide network 12 and 18 for providing electromagnetic energy of at least one polarization. Coupled to the circular waveguide network 12 and 18 is a dielectric-loaded waveguide arrangement 22 for projecting a first electromagnetic beam. The inventive antenna 10 further includes a parasitic element network 32, 34, and 36 positioned in the path of the first beam. The parasitic element network 32, 34, and 36 is disposed to form a parasitic beam in response to the first beam. In a particular embodiment of the inventive antenna 10 a beam shaping cone 40 circumscribes the dielectric waveguide arrangement 22. The cone 40 is adapted to augment the elevation angle A characterizing the antenna 10 of the present invention by redirecting the parasitic beam.Type: GrantFiled: May 17, 1990Date of Patent: August 6, 1991Assignee: Hughes Aircraft CompanyInventors: Mon N. Wong, Samuel S. Wong, Gregory D. Kroupa, Robert C. Perpall
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Patent number: 4989014Abstract: A reception antenna system for electrical connection to the positive and negative sides of a transmission feedline employed in television and other telecommunications includes a reflector having a conductive surface and further having a circumferential raised edge to provide reflected signals to the reflector. The system includes an even group of electrically open-ended radial pairs, having positive and negative ends, of hollow, substantially scalene triangular conductive loops, each loop of each pair being internally symmetric about a radius of the reflector, each pair of the group disposed at an uniform offset from the surface of the reflector, the offset defined by insulative mounting elements.Type: GrantFiled: November 6, 1989Date of Patent: January 29, 1991Inventor: Louis Kocsi
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Patent number: 4949094Abstract: A parasitic array for use on a transmission/reception antenna which comprises a cylindrical dielectric support having plural conductive, ring-like parasitic elements spaced along the support. The support is an elongate, hollow structure with closed ends and the parasitic elements are formed of a conductive film applied to the outer surface of the support.Type: GrantFiled: January 23, 1985Date of Patent: August 14, 1990Assignee: Spatial Dynamics, Ltd.Inventor: Tex Yukl
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Patent number: 4864320Abstract: The subject invention relates to antennas having substantially greater bandwidth and low angle gain of the type for the transceiving of circularly/elliptically polarized electromagnetic waves. The antenna structure comprises a ground plane, a source of linearly-polarized wave energy field associated with said ground plane, and a plurality of conductive elements having an L-shape, said elements equally spaced from one another and equiangularly disposed about the sources, said plurality of elements being in a form of a circular arrangements, each element being so disposed as to fall on the circumference of the circular arrangement, each element lying in a common plane orthogonal to the linearly-polarized wave energy field provided by said source. The subject invention has special utility in motor and marine craft for communication and navigation.Type: GrantFiled: May 6, 1988Date of Patent: September 5, 1989Assignee: Ball CorporationInventors: Michael G. Munson, Robert E. Munson, Patrick M. Westfeldt, Jr., Farzin Lalezari
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Patent number: 4860020Abstract: A compact, wideband antenna system is provided by an open-sleeve, meander dual zigzag monopole consisting of a driven element configured from two symmetrically-oriented meander wires fed from a common feed point and one or two closely-spaced parasitic elements (open sleeves), also configured from two meander wires and shorted to ground plane. The meander monopole has a low silhouette and provides approximately 50% reduction in height as compared to a conventional monopole. By varying the size, geometry, and location of the open sleeves, antennas are synthesized to achieve specific frequency response characteristics. Measurements have demonstrated that the meander monopole is capable of providing the desired radiation pattern characteristics over a 3:1 frequency band.Type: GrantFiled: April 30, 1987Date of Patent: August 22, 1989Assignee: The Aerospace CorporationInventors: Jimmy L. Y. Wong, Howard E. King
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Patent number: 4853705Abstract: The invention relates to an antenna for receiving and modulating transmitted signals having a very low power density on the order of below 1 watt per meter squared, at a selected center frequency above 2,000 MHz. The antenna uses a folded planar dipole section having two separated oppositely disposed U-shape elements, each of said elements having a pair of ends. A capacitor is series-coupled between two of the oppositely disposed ends of the elements, and a diode having a high impedance at the selected center frequency is series-coupled between the other two oppositely disposed ends of the U-shape elements. A metallic backplane is mounted parallel to the planar folded dipole section and spaced from the dipole section a predetermined distance selected to reduce the antenna impedance. The impedance of the diode, the shape of the folded planar diode section and the predetermined amount of spacing of the backplane from the planar folded dipole section are all selected to increase the d.c.Type: GrantFiled: May 11, 1988Date of Patent: August 1, 1989Assignee: Amtech Technology CorporationInventor: Jeremy A. Landt
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Patent number: 4849765Abstract: A low-profile antenna for operating in the 800 to 900 mHz range and especially suited for use with portable, hand-held electronic apparatus. The antenna features printed circuit board construction for precision fabrication, broadband operations and enhanced efficiency. The antenna includes a driven element in close association with a parasitic element printed on one surface of the printed circuit board in a side-by-side, parallel relation. A conductive strip is included on the other side of the board spanning the free ends of the driven and parasitic elements to enhance the coupling therebetween.Type: GrantFiled: May 2, 1988Date of Patent: July 18, 1989Assignee: Motorola, Inc.Inventor: Paul D. Marko
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Patent number: 4829312Abstract: The present invention is applied to a slotted waveguide antenna assembly which comprises a slotted waveguide having a plurality of slots, a reflector having an aperture in front of the slotted waveguide and reflecting radiated electromagnetic wave for forming directive beam, and a mounting portion for mounting the antenna assembly onto a place where the antenna assembly is to be installed.In such an antenna assembly, a fixing member is provided on the reflector at a position spaced from the slotted waveguide. The fixing member extends between the opposite walls of the reflector and fixed thereto. The fixing member has an end which projects outwardly from the wall of the reflector to form the mounting portion. The fixing member is sufficiently thin as compared with the working wavelength.The slotted waveguide antenna assembly may have a dielectric wave-guiding arrangement.Type: GrantFiled: January 22, 1987Date of Patent: May 9, 1989Assignee: Tokyo Keiki Co., Ltd.Inventors: Takashige Terakawa, Mutsumi Takahashi, Noriyuki Akaba
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Patent number: 4804971Abstract: A guy system is disclosed for a parabolic reflecting antenna having a reflecting surface and a signal receiver or feedhorn mounted at its focal point. A plurality of stays or guy wires is secured to the feedhorn, each of such guy wires extending through the reflecting surface to an anchor point behind the antenna substantially at or near its vertex. The resultant force acting on the antenna as a result of tension in the guy wires is thereby substantially tangential to the curvature of the reflecting surface.Type: GrantFiled: April 16, 1986Date of Patent: February 14, 1989Assignee: Chapparral CommunicationsInventors: Robert W. Bruns, Douglas Kotval
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Patent number: 4785304Abstract: A phase scan antenna array for planar radar scanning in a single plane with pencil-shaped beam is provided comprising a plurality of ferrite rod line source antennas. Each rod antenna has a plurality of beam-emitting slots spaced along one side thereof and is end fed in phase with the other antennas from a single hollow metallic waveguide by means of coupling slots in the waveguide which are spaced apart one wavelength of the radar frequency. The rods are mounted in a two-dimensional columnar array with the beam-emitting slots of each rod aligned in rows with the corresponding slots of the other rods by a mounting member having a plurality of mutually-parallel slots in which the rods are disposed. The walls of the mounting member slots suppress Faraday rotation of the waves in the rods and the bottom of the slots enhance the single beam emitted from the face of the array.Type: GrantFiled: November 20, 1986Date of Patent: November 15, 1988Assignee: The United States of America as represented by the Secretary of the ArmyInventors: Richard A. Stern, Richard W. Babbitt, Gerald F. Mikucki
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Patent number: 4761055Abstract: Retroreflector for the reflection of electromagnetic rays suitable for destroying, by reflection or absorption, electromagnetic radiation, which could lead to a lasting detrimental influencing of magnetic or other data carriers. The retroreflector is constructed as a flat article formed from a base layer of metallic, juxtaposed reflectors with filter coatings applied thereto formed from a suitable metallic material, and provided with top coatings on a bottom surface and a top surface of the base layer.Type: GrantFiled: September 29, 1986Date of Patent: August 2, 1988Assignee: Helmut K. Pinsch GmbH & Co.Inventor: Gunter H. Hatje
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Patent number: 4719470Abstract: A relatively broadband printed circuit antenna structure includes a dielectric sheet having printed circuit-like conductive structures printed on both sides in predetermined registration with one another. A traditional non-radiating microstrip transmission line structure extends from a common r.f. feedpoint to at least one terminal end portion. However, apertures disposed within the underlying (or overlying) conductive reference surface of the double-cladded printed circuit board in the vicinity of each terminal end cause substantial r.f. radiation to occur over a relatively broader bandwidth than with a more traditional microstrip antenna radiator structure. In one embodiment, the aperture in the microstrip ground plane itself becomes a radiating aperture due to the transmission line currents flowing within the ground plane.Type: GrantFiled: May 13, 1985Date of Patent: January 12, 1988Assignee: Ball CorporationInventor: Robert E. Munson
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Patent number: 4628322Abstract: A low profile antenna comprised of a driven element and a parasitic element spaced above a ground plane. The driven element is connected at one end to the feedpoint of the radio device to which it is attached, the opposite end thereof being free. The parasitic element is connected to the ground plane by its end nearest the feedpoint, the opposite end thereof being free. In the preferred embodiment the parasitic element length and the driven element length are both approximately equal to a quarter wavelength at the operating frequency.Type: GrantFiled: March 17, 1986Date of Patent: December 9, 1986Assignee: Motorola, Inc.Inventors: Paul D. Marko, Thomas F. Kneisel, Oscar M. Garay
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Patent number: 4611214Abstract: A vertically polarized array comprised of both bottom fed and top fed conurations having a driven element comprising at least one but, when desirable, two generally horizontal wire conductor segments of a length substantially equal to one half the operating wavelength of the array and with the ends of the half-wave conductor segments being connected to or extending into generally vertical quarter wavelength wire conductor segments. In a bottom fed configuration the feedpoint is at the bottom end of one vertical quarter wavelength conductor segment while in a top fed configuration one vertical quarter wavelength segment comprises a quarter wavelength of coaxial transmission line having one end configured into signal isolation means, comprising a cable choke, while the feedpoint is located at the other end.Type: GrantFiled: June 27, 1984Date of Patent: September 9, 1986Assignee: The United States of America as represented by the Secretary of the ArmyInventors: Donn V. Campbell, Palemon W. Dubowicz, Felix Schwering
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Patent number: 4591863Abstract: A low profile antenna structure includes a substantially planar conductive sheet having a substantially planar conductive member extending from one end at a normal angle. A driven radiating element and a parasitic radiating element are disposed adjacent the conductive sheet. A feed point is coupled to the driven element for coupling RF energy to and from the antenna. Both the driven and the parasitic elements are approximately one quarter wavelength long and are approximately parallel to one another and are situated approximately 1/20th of a wavelength apart.Type: GrantFiled: April 4, 1984Date of Patent: May 27, 1986Assignee: Motorola, Inc.Inventor: Stelios J. Patsiokas
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Patent number: 4584585Abstract: A low profile antenna comprised of a driven element and a parasitic element spaced above a ground plane. The driven element is connected at one end to the feedpoint of the radio device to which it is attached, the opposite end thereof being free. The parasitic element is connected to the ground plane by its end nearest the feedpoint, the opposite end thereof being free. In the preferred embodiment the parasitic element length and the driven element length are both approximately equal to a quarter wavelength at the operating frequency.Type: GrantFiled: April 4, 1984Date of Patent: April 22, 1986Assignee: Motorola, Inc.Inventors: Paul D. Marko, Thomas F. Kneisel, Oscar M. Garay
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Patent number: 4502053Abstract: A circularly polarized electromagnetic-wave radiator, formed from a rectangular section waveguide and a dipole, is energized directly by the guide and placed in the extension of its largest faces. An associated reflector element enables coincidence of the two respective phase centers of the guide and the dipole.Type: GrantFiled: May 10, 1982Date of Patent: February 26, 1985Assignee: Thomson-CSFInventors: Albert Dupressoir, Francois Salvat
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Patent number: 4494120Abstract: An antenna is provided which exhibits a low profile. The antenna includes a counterpoise of electrically conductive material and a passive element oriented substantially parallel thereto. The ends of the passive element are electrically coupled to the counterpoise surface. An active element of electrically conductive material includes a middle portion and first and second outer end portions. The middle portion is situated adjacent and spaced apart from the passive element by a predetermined distance and in a parallel relationship therewith. The first outer end portion of the active element is bent toward the grounded end of the passive element nearest thereto. The first outer end portion represents a feedpoint of the antenna with respect to the counterpoise. The remaining second outer end portion the active element is bent towards the remaining end of the passive element nearest thereto.Type: GrantFiled: April 29, 1983Date of Patent: January 15, 1985Assignee: Motorola, Inc.Inventor: Oscar M. Garay
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Patent number: 4290071Abstract: A multi-band multi-element directional antenna array having a driven element and at least one parasitic element with a network at the center of each element interconnecting element opposite side radiators. While some of these would be a driven element and either a reflector or director parasitic element array most applications call for at least three elements, a driven element, a reflector element and a director element, and for some applications, additional parasitic director elements are added. While antenna arrays embodying features hereof may be adapted as two band f.sub.1 f.sub.2, f.sub.2 f.sub.3, or f.sub.1 f.sub.3 antenna arrays, primary useage would be in a three radio band f.sub.1, f.sub.2, f.sub.3 version with band nominal center frequencies related, approximately by the progression 1, 1.5, 2 (example 14, 21, and 28 MHz).Type: GrantFiled: December 23, 1977Date of Patent: September 15, 1981Assignee: Electrospace Systems, Inc.Inventor: Richard C. Fenwick
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Patent number: D440965Type: GrantFiled: May 23, 2000Date of Patent: April 24, 2001Assignee: DX Antenna Company, LimitedInventor: Shigemi Inoue