US3871000A - Wide-band vertically polarized omnidirectional antenna - Google Patents

Wide-band vertically polarized omnidirectional antenna Download PDF

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Publication number
US3871000A
US3871000A US420581A US42058173A US3871000A US 3871000 A US3871000 A US 3871000A US 420581 A US420581 A US 420581A US 42058173 A US42058173 A US 42058173A US 3871000 A US3871000 A US 3871000A
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United States
Prior art keywords
metal surface
wide
slot
omnidirectional antenna
vertically polarized
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
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US420581A
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English (en)
Inventor
Gerhard Tymann
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Airbus Defence and Space GmbH
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Messerschmitt Bolkow Blohm AG
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Application granted granted Critical
Publication of US3871000A publication Critical patent/US3871000A/en
Priority to US05/581,265 priority Critical patent/US4005112A/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
    • H01Q13/00—Waveguide horns or mouths; Slot antennas; Leaky-waveguide antennas; Equivalent structures causing radiation along the transmission path of a guided wave
    • H01Q13/10—Resonant slot antennas
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q21/00—Antenna arrays or systems
    • H01Q21/06—Arrays of individually energised antenna units similarly polarised and spaced apart
    • H01Q21/20—Arrays of individually energised antenna units similarly polarised and spaced apart the units being spaced along or adjacent to a curvilinear path
    • H01Q21/205—Arrays of individually energised antenna units similarly polarised and spaced apart the units being spaced along or adjacent to a curvilinear path providing an omnidirectional coverage

Definitions

  • a wide-band vertically polarized omnidirectional antenna consists of an outer first cylindrically-shaped metal surface with a second cylindrically-shaped metal surface coaxial with and located within the first metal surface and concentrically disposed about a third cylindrically-shaped metal surface.
  • the first metal surface is formed of individual antenna elements each having a ring of circumferentially extending slots spaced axially from the ends of the elements with adjacent elements spaced apart by a circumferential ring slot.
  • the first metal surface can be a continuous tubular member divided in the axial direction by a number of axially spaced rings of circumferentially extending slots.
  • Each ring of slots consists of a number of uniformly circumferentially spaced rectangularly-shaped slots.
  • a three-wire line is associated with each ring of slots with two of the wires extending circumferentially while the third or inner wire extends radially inwardly from the first metal surface through the second metal surface in contact-free relationship and then into contact with the third metal surface.
  • the present invention is directed to a wideband, vertically polarized omnidirectional antenna and, more particularly, it concerns the arrangement of such antenna and especially its outer surface which is formed of a hollow cylindrical metal surface divided by circumferentially extending rings of slots located in planes extending perpendicular to the axis of the metal surface.
  • the rings of slots are arranged to divide the first surface into hollow cylinders having a height or axial length of about A to A of the wavelengths.
  • a three-wire line feeds each of the ring slots and a second hollow cylindrically-shaped metal surface disposed inwardly of and coaxially with the first metal surface serves as a meter frame or support.
  • antennas with a good circular radiation pattern or characteristic are required in a plane with medium gain.
  • the ability to withstand extremely high temperature stresses from about 80C to +200C is required in many space probes, for example, in solar probes.
  • the antenna dimensions, particularly the diameter are given.
  • several antennas must be superposed with a magnetometer arranged at the end of the antenna arm. The necessary feed lines for the upper antennas and for the magnetometer must be arranged within the interior of the lower antennas.
  • slot radiators which consist of two coaxial hollow cylindrical metal surfaces where the outer metal surface contains a circumferentially extending ringslot located in a plane disposed perpendicularly to the axis of the metal surface.
  • the inner metal surface serves as a meter frame or support.
  • Two hollow cylindrical rings separated by a ring slot form a slot radiator element.
  • the outer hollow cylindrical surface is secured over narrow stirrups on the inner hollow cylindrical metal surface.
  • the omnidirectional antennas mentioned in the two publications use the two outer conductors of the three-wire symmetrization to maintainthe distance of the outer hollow cylinders. These known omnidirectional antennas do not meet, however, the mechanical stability requirements for air and space travel. Reinforcement of the supports is not possible without, at the same time, impairing the electrical properties of the omnidirectional antenna.
  • a low-loss dielectric must be found which can withstand at least 200C. Further, it is very difficult, particularly with regard to thermal and mechanical stresses, to obtain good contact'between the dielectric and the metal surface. When large temperature fluctuations occur, an air gap develops due to the different coefficients of expansion of the metal and dielectric. Since the electrical field strength in the air gap is higher than in the dielectric, a breakdown may occur. Moreover, the antenna becomes highly frequency-sensitive, particularly in the form of a coaxial line radiator (note the Silver publication mentioned above).
  • the omnidirectional antenna described in the abovementioned patent is fed over two-wire lines arranged within hollow cylindrically-shaped rings. With many feeding points and several ring slots, such a system becomes very complicated and unwieldy, particularly since impedance converters and concentrated blind elements must be inserted into the feeding line system.
  • the space within the second hollow cylindrically-shaped metal surfaces is designed as a tubular or coaxial conductor.
  • the high-frequency energy is uncoupled over probes and is fed to the ring slots.
  • the tubular conductor must have a corresponding diameter.
  • a certain diameter ratio of the outer to the inner conductor must be maintained in view of wave resistance. If the diameter of the inner conductor is selected at a dimension such that a foreign cable can be laid within its interior, the diameter of the antennais frequently too great in respect to the wavelengths. In any case, it is not possible to arrange thicker supply lines for components arranged above the omnidirectional antenna inside the hollow cylindrically-shaped metal surfaces in the proximity of the antenna axis.
  • the use of ring slots with discrete feeding results in a lack of symmetry in the radiation diagram.
  • the radiation diagram can be influenced in the azimuth only by the number of coupling points and the diameter of the omnidirectional signal. Further, wide-band coupling of the ring slots is hardly possible.
  • the primary object of the present invention is to provide an antenna with a good circular radiation characteristic in a plane and of great band width, where the quality of the circular radiation is, for all practical purposes, independent of the diameter of the antenna and where the antenna has both high mechanical and thermal strength with easy mountability and a simple and insensitive feeding system. Further, the arrangement of the antenna permits the placement of additional supply cables inside the antenna structure particularly in the proximity of its axis.
  • the problems experienced in the past are solved in the present invention by dividing the ring slot in a uniform manner into individual or separate circumferentially extending slots spaced apart in the circumferential direction.
  • the individual slots can have a rectangular form or they can be widened conically or in steps, or they can be arranged as dumbbellshaped slots and each individual slot is fed over a threewire line from one or more coaxial conductors, and, if necessary, a third hollow cylindrically-shaped metal surface is provided inwardly of the first and second such surfaces.
  • the second and third hollow cylindrically-shaped surfaces are designed as a feeding system for the antenna arrangement and the inner wires or conductors of the three-wire line pass inwardly from the first metal surface in contact-free relationship through bores in the second metal surface and are coupled capacitatively or galvanically with the third metal surface.
  • Concentration of the radiation in a plane through the system axis is achieved by providing a ring of individual slots in an omnidirectional radiator element so that two hollow cylinder rings are formed and by arranging several such omnidirectional radiator elements, whose height is about equal to half the mean operating wavelength, in a superposed coaxially arranged group with the individual radiator elements spaced apart in the axial direction by a circumferential ring slot.
  • the omnidirectional radiator elements are joined together in the form of a continuous tubular member provided with the individual interrupted ring slots but without the separating circumferential ring slots.
  • the feeding or supply which is not limited to the antenna according to the present invention, is effected in the wide-band model in such a way that at least one coaxial conductor is positioned within the third hollow cylindrically-shaped metal surface and acts as a coaxial feed conductor with the outer wire of the feed conductor conductively connected to the third metal surface and with its inner conductor conductively connected to the second metal surface.
  • the feed arrangement is laid out so that the coaxial connection to the feed is arranged in the center of the antenna structure with the outer wire of the coaxial feed conductor conductively connected to the third hollow cylindrically-shaped metal surface over a hollow cylinder extension extended through an opening in the third metal surface and attached to it by a through connection and with the inner wire of the coaxial feed conductor passing outwardly through the hollow cylinder extension within another cylindrically-shaped member and attached to the exterior of the second metal surface.
  • an adjustable and fixable short-circuit plane is provided at the free end of the coaxial feed conductor at a distance of about $41 of the mean operating wavelength for adjusting the amplitude and phase conditions in the coaxial feed conductor.
  • the present invention it is possible to obtain a good circular radiation characteristic in a plane which is, to a great extent, independent of the ratio of the antenna diameter to the wavelength.
  • By using individual spaced slots in the interrupted ring of slots and by using different geometric forms for the slots it is possible to obtain optimum wide-band matching.
  • the symmetry of the arrangement can be improved, if necessary, by varying the lengths of the single or individual slots, or a designed asymmetry can be produced in the radiation pattern.
  • the single slots and the use of larger antenna diameters which is possible because of the independence of the quality of the circular radiation characteristic from the antenna diameter/wavelength ratio, a very high mechanical strength is obtained, particularly in the design which does not use separating ring slots between individual radiator elements.
  • the omnidirectional antenna without the use of the third hollow cylindrically-shaped surface by using a tubular conductor arrangement.
  • the third metal surface could be used as an outer wire of a coaxial feed line.
  • the advantages of wideband cabling and of incorporating other cables close to the axis of the antenna would not be available.
  • FIG. 1a is a partial view, partly in section, of an omnidirectional antenna embodying the present invention, and incorporating radiator elements having a length of about one-half the wavelength;
  • FIG. lb is a view similar to FIG. la, embodying the present invention with a continuous outer hollow cylindrically-shaped metal surface in place of the individual radiator elements;
  • FIG. 2 is an enlarged sectional view showing the feeding arrangement for the antenna.
  • FIG. 3a to 30 show possible forms of the individual slots.
  • an omnidirectional antenna is illustrated with its outer surface formed of a plurality of collinear radiator elements 12 each having a height or axial length of about 5% the wavelength.
  • the individual radiator elements 12 are spaced apart in the axial direction of the antenna by circumferentially extending slots 3 formed between adjacent ends of the elements.
  • an interrupted ring of rectangularly shaped individual slots 4 extend in the circumferential direction of the elements.
  • Each individual slot 4 is fed over a three-wire line 5, 8, 9.
  • the outer wires 8, 9 of the three-wire line serve to maintain the distance of the elements 12 from a radially inner hollow cylindrically-shaped metal surface which is arranged coaxially with the radiator elements.
  • a third hollow cylindrically-shaped metal surface 14 is located coaxially within the second metal surface 10.
  • Each inner wire 5 of the three-wire line is connected at its radially outer end to a nose 7 which protrudes in the axial direction from the surface of the radiator element 12 into the slot 4. Bores are formed in the second hollow metal surface 10 so that each of the inner wires 5 passes inwardly through the bore in contact-free relationship from the second metal surface 10 and is conductively connected'to the third metal surface 14.
  • FIG.'lb another embodiment of the omnidirectional antenna is illustrated which has the same design as shown in FIG. 1a.
  • the radiator elements 12 are formed in a continuous tubular metal surface 2 in which the rows of individual slots 4 extending circumferentially about the tubular member 2 are spaced apart at about the mean operating wavelength.
  • FIG. 2 a feeding arrangement for the invention is illustrated.
  • the coaxial conductor 16 opens into an outer cylinder 20 which forms'a coaxial conductor together with an inner conductor member 21 which is connected to the conductor 16.
  • the outer wire of the coaxial conductor 16 is conductively connected with the hollow cylinder 20- and its inner wire is conductively connected with the inner conductor member 21.
  • the hollow cylinder is disposed tangentially to the inner surface of the third hollow metal surface 14.
  • a hollow cylindrical extension 23 extends normally to the axis of the hollow cylinder and outwardly from it passing through an opening in the third metal surface 14 and it is secured by a screw conductor 24 to the outside surface of the third metal surface 14.
  • an adjustable and fixable short-circuit plane is arranged in the innermost coaxial conductor to compensate or adjust the amplitude and phase conditions within the feed arrangement.
  • the outermost hollow cylindrically-shaped metal surface 2 that is the radiator elements 12, contains the slot radiators which radiate a vertically polarized electromagnetic wave.
  • the next inner hollow cylindrical metal surface 10 serves as a meter frame or support as well as an outer wire for the coaxial feed system of the antenna arrangement and as a reflector.
  • the inner wire of the coaxial feed conductor is in contact with this second metal surface 10.
  • the innermost hollow cylindrically-shaped metal surface 14 forms the inner wire for the coaxial feed system and it is connected with the outer wire of the coaxial feed conductor.
  • FIG. 3a shows an individual slot, which widens conically and FIG. 3b an individual slot, which widens in steps.
  • FIG. 3c shows an individual slot with dumbbelllike shape. In the middle of the axial length of this dumbbell-like shaped slot 4" a projection extends into the slot.
  • the omnidirectional antenna according to the invention can also be designed for horizontal polarization.
  • the feeding device disclosed above is not limited to antennas of the type described herein, it also applies generally to individual radiator elements or radiator groups.
  • Preferred applications of the omnidirectional antenna according to the invention are for air and space travel, as well as in mobile and stationary telemetry stations.
  • the omnidirectional antenna described is particularly suitable for the superposition of several antennas.
  • Another advantageous application of the antenna of the present invention is as a primary radiator for reflection antennas, particularly for cylindrical-parabolic antennas.
  • the wide-band vertically polarized omnidirectional antenna has a wavelength of about 5,5 inches.
  • Typical diameter dimensions of the first, second and third hollow cylindrically-shaped metal surfaces would be as follows: 3, 1,5 inches and 1 inch.
  • the axial lengths of the antenna elements 12 would be 0,45 wavelengths.
  • the spacing between the interrupted rings of slots 4 in FIG. 1b would be of the wavelength.
  • a wide-band vertically polarized omnidirectional antenna comprisinga first hollow cylindrically-shaped metal surface divided transversely of its axis by a circumferentially extending slot into at least two hollow cylindrically-shaped rings having an axial length of $41 or k of thewavelength, three-wire lines distributed uniformly over the circumference of said first metal surface for feeding said slots, and a second hollow cylindrically-shaped metal surface arranged within and coaxially with said first metal surface as a support, wherein the improvement comprises that said slot is formed of a plurality of circumferentially extending individual slots uniformly spaced apart in thecircumferential direction and forming a circumferentially extending interrupted ring slot, one said three-wire line for feeding each said individual slot, at least one coaxial conductor positioned within said second metal surface, said second metal surface and said coaxial conductor arranged as a coaxial feeder system, said three-wire line comprising inner wires extending radially inwardly from said first metal surface, said second metal surface having bores therethrough aligned
  • a wide-band vertically polarized omnidirectional antenna as set forth in claim 1, wherein a third hollow cylindrically shaped, metal surface is positioned within said second metal surface, said third metal surface comprising one or several coaxial conductors in order to feed the antenna system and, if necessary, comprising also other conductors and feed lines not used for feeding the antenna system, said second metal surface and said third metal surface arranged as a coaxial feeder system of the antenna, said three-wive line comprising inner wires extending radially inwardly from said first metal surface, said second metal surface having bores therethrough aligned with said inner wife so that said inner wife pass contact-free through said second metal surface and are coupled capacitatively or galvanically with said third metal surface.
  • a wide-band vertically polarized omnidirectional antenna as set forth in claim 1, wherein said individual slots are rectangular in form.
  • a wide-band vertically polarized omnidirectional antenna as set forth in claim 3, wherein a projection on said first hollow cylindrically-shaped metal surface extends into said rectangularly shaped slot from one side thereof and is spaced from the other side thereof, and one said inner wire of said three-wire line being coupled with said projection into said slot.
  • a wide-band vertically polarized omnidirectional antenna as set forth in claim 1, wherein said individual slots have conically widening configuration.
  • a wide-band vertically polarized omnidirectional antenna as set forth in claim 1, wherein said individual slots widen in a step-wise manner.
  • a wide-band vertically polarized omnidirectional antenna as set forth in claim 1, wherein said individual slots have a dumbbell-like shape.
  • a wide-band vertically polarized omnidirectional antenna as set forth in claim 7, wherein a projection on said first hollow cylindrically-shyped metal surface extends into said dumbbell-like shaped slot from one side thereof and is spaced from the other side thereof, and one said inner wire of said three-wire line being coupled with said projection into said slot.
  • A. wide-band vertically polarized omnidirectional antenna as set forth in claim 1, wherein said first metal surface comprises a plurality of cylindrically-shaped omnidirectional antenna elements arranged in surface alignment, each said antenna element having an axial length about equal to half the mean operating wavelength, said antenna elements being spaced apart in the axial direction and forming a continuous circumferentially extending slot therebetween, and each said antenna element having said interrupted ring slot therein positioned axially from and intermediate its opposite ends.
  • a wide-band vertically polarized omnidirectional antenna as set forth in claim 1, wherein said first metal surface comprises a continuous axially elongated tubular member having a plurality of axially spaced said interrupted ring slots therein dividing said tubular member into a plurality of interconnected omnidirectional antenna elements.
  • a wide-band vertically polarized omnidirectional antenna as set forth in claim 2, wherein at least a part of oneof said coaxial conductors comprises an axially elongated hollow cylinder forming an outer conductor and an axially elongated inner conductor positioned coaxially within and spaced inwardly from said hollow cylinder, said hollow cylinder connected conductively to said third metal surface and said inner conductor connected conductively to said second metal surface.
  • A- wide-band vertically polarized omnidirectional antenna as set forth in claim 11, wherein said hollow cylinder forming the outer conductor is in surface contact with the surface of said third metal surface and said third metal surface having an opening therethrough, said hollow cylinder having a tubular-shaped extension secured thereto and extending laterally outwardly therefrom transversely of the axial direction of said hollow cylinder through the opening in said third metal surface, a threaded connector member in screwed engagement with the outer surface of said extension for fixing said hollow cylinder to said third metal surface, said second metal surface having an opening therethrough aligned with the opening in said third metal surface, a hollow cylindrically-shaped member secured to the outer surface of said second metal surface and extending through the opening in said second metal surface and through said tubularshaped extension secured to said hollow cylinder and in spaced relationship to said tubular-shaped extension, and a connector member displaceably mounted in said hollow cylindrically-shaped member and connected to and phase conditions in said coaxialconductor.

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  • Waveguide Aerials (AREA)
  • Variable-Direction Aerials And Aerial Arrays (AREA)
US420581A 1972-12-02 1973-11-30 Wide-band vertically polarized omnidirectional antenna Expired - Lifetime US3871000A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US05/581,265 US4005112A (en) 1973-11-30 1975-05-27 Multistep method for preparation of tetrahydrofuran starting from propylene, oxygen and a carboxylic acid

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE2259082A DE2259082A1 (de) 1972-12-02 1972-12-02 Breitbandige, vertikal polarisierte rundstrahlantenne

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US05/581,265 Division US4005112A (en) 1973-11-30 1975-05-27 Multistep method for preparation of tetrahydrofuran starting from propylene, oxygen and a carboxylic acid

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US3871000A true US3871000A (en) 1975-03-11

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US420581A Expired - Lifetime US3871000A (en) 1972-12-02 1973-11-30 Wide-band vertically polarized omnidirectional antenna

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US (1) US3871000A (enExample)
JP (1) JPS4989460A (enExample)
DE (1) DE2259082A1 (enExample)
FR (1) FR2209226B1 (enExample)
GB (1) GB1419283A (enExample)
IT (1) IT1001963B (enExample)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3949405A (en) * 1973-12-21 1976-04-06 Thomson-Csf Vertically polarised omnidirectional antenna
US4468675A (en) * 1981-11-04 1984-08-28 Robinson Lawrence P Shortened antenna with coaxial telescoping cylinders
US5105199A (en) * 1989-08-17 1992-04-14 Alliance Telecommunications Corporation Method and apparatus for tube element bracket
DE4308604A1 (de) * 1993-03-18 1994-09-22 Kolbe & Co Hans Lineare Gruppenantenne mit Rundstrahlcharakteristik
WO1999043046A1 (en) * 1998-02-18 1999-08-26 Ems Technologies, Inc. Geodesic slotted cylindrical antenna
US6020860A (en) * 1997-04-29 2000-02-01 Howell Laboratories, Inc. Antenna inner conductor and shorts system
US6356241B1 (en) * 1998-10-20 2002-03-12 Raytheon Company Coaxial cavity antenna
US20100134360A1 (en) * 2007-01-11 2010-06-03 Byung Hoon Ryou Integrated antenna of parallel-ring type
US20100309082A1 (en) * 2009-06-09 2010-12-09 Dbspectra, Inc. Omnidirectional antenna radiation element
US10826179B2 (en) 2018-03-19 2020-11-03 Laurice J. West Short dual-driven groundless antennas
CN115296027A (zh) * 2022-08-05 2022-11-04 四创电子股份有限公司 一种新型并馈馈电全向天线

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2973515A (en) * 1957-04-05 1961-02-28 Alford Andrew Omnidirectional vertically polarized antenna
US3417400A (en) * 1966-04-25 1968-12-17 Administrator Of The Nat Acron Triaxial antenna

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2935747A (en) * 1956-03-05 1960-05-03 Rca Corp Broadband antenna system
US2895133A (en) * 1956-05-22 1959-07-14 Applic Rech Electronique Wide-band antenna

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2973515A (en) * 1957-04-05 1961-02-28 Alford Andrew Omnidirectional vertically polarized antenna
US3417400A (en) * 1966-04-25 1968-12-17 Administrator Of The Nat Acron Triaxial antenna

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3949405A (en) * 1973-12-21 1976-04-06 Thomson-Csf Vertically polarised omnidirectional antenna
US4468675A (en) * 1981-11-04 1984-08-28 Robinson Lawrence P Shortened antenna with coaxial telescoping cylinders
US5105199A (en) * 1989-08-17 1992-04-14 Alliance Telecommunications Corporation Method and apparatus for tube element bracket
DE4308604A1 (de) * 1993-03-18 1994-09-22 Kolbe & Co Hans Lineare Gruppenantenne mit Rundstrahlcharakteristik
US6020860A (en) * 1997-04-29 2000-02-01 Howell Laboratories, Inc. Antenna inner conductor and shorts system
US6011520A (en) * 1998-02-18 2000-01-04 Ems Technologies, Inc. Geodesic slotted cylindrical antenna
WO1999043046A1 (en) * 1998-02-18 1999-08-26 Ems Technologies, Inc. Geodesic slotted cylindrical antenna
US6356241B1 (en) * 1998-10-20 2002-03-12 Raytheon Company Coaxial cavity antenna
US20100134360A1 (en) * 2007-01-11 2010-06-03 Byung Hoon Ryou Integrated antenna of parallel-ring type
US20100309082A1 (en) * 2009-06-09 2010-12-09 Dbspectra, Inc. Omnidirectional antenna radiation element
US8421701B2 (en) * 2009-06-09 2013-04-16 dcSpectra, Inc. Omnidirectional antenna radiation element
US10826179B2 (en) 2018-03-19 2020-11-03 Laurice J. West Short dual-driven groundless antennas
US11605890B2 (en) 2018-03-19 2023-03-14 Laurice J. West Short dual-driven groundless antennas
CN115296027A (zh) * 2022-08-05 2022-11-04 四创电子股份有限公司 一种新型并馈馈电全向天线

Also Published As

Publication number Publication date
JPS4989460A (enExample) 1974-08-27
GB1419283A (en) 1975-12-31
IT1001963B (it) 1976-04-30
FR2209226B1 (enExample) 1978-06-16
DE2259082A1 (de) 1974-06-06
FR2209226A1 (enExample) 1974-06-28

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