US3569977A - Hexagram antenna - Google Patents

Hexagram antenna Download PDF

Info

Publication number
US3569977A
US3569977A US786911A US3569977DA US3569977A US 3569977 A US3569977 A US 3569977A US 786911 A US786911 A US 786911A US 3569977D A US3569977D A US 3569977DA US 3569977 A US3569977 A US 3569977A
Authority
US
United States
Prior art keywords
elements
antenna
base
ground plane
radiating
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
Application number
US786911A
Inventor
William B Koller
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Goodyear Aerospace Corp
Original Assignee
Goodyear Aerospace Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Goodyear Aerospace Corp filed Critical Goodyear Aerospace Corp
Application granted granted Critical
Publication of US3569977A publication Critical patent/US3569977A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01QANTENNAS, i.e. RADIO AERIALS
    • H01Q11/00Electrically-long antennas having dimensions more than twice the shortest operating wavelength and consisting of conductive active radiating elements
    • H01Q11/02Non-resonant antennas, e.g. travelling-wave antenna
    • H01Q11/08Helical antennas

Definitions

  • flExfscRAM ANTENNA ABSTRACT Two triangular radiating elements are interlaced 7 Chum 4 Drawmg Figs in a helical winding about a common axis to form a single an- [52] U.S. Cl. 343/848, tenna structure. The elements are wound in opposite 343/895 directions and are laterally separated, thus reducing the RP [51] Int.
  • ATTORNEYS HEXAGltAli/l ANTENNA ll-lleretofore the use of helical antennas has been well known, with these antennas designed to provide a predetermined directional radiating and reception pattern.
  • Various methods have been utilized'to achieve circularity in the patterns, and to prevent mutual RF coupling between separate radiating elements if more than one element is utilized.
  • the problem of preventing mutual RP coupling, and obtaining dual circularity in one composite antenna structure is needed by the art.
  • FIG. 1 is a side elevational view of an antenna made according to one embodiment of the invention.
  • FIG. 2 is a cross-sectional plan view of the antenna of FIG. ll taken on line 2-2 thereof;
  • FIG. 3 is an enlarged broken away side view of the base of the antenna of FIG. 1 showing how the feed is provided to the separate radiating elements;
  • FIG. 4 is a cross-sectional plan viewof a second embodiment of the antenna of the present invention.
  • the numeral indicates generally an elongated supporting post having an axis which is carried by a mounting base 112 in any conventional manner so the axis is substantially normal to the surface of the base 12.
  • the post is preferably hexagonal in cross section as seen in FIG. 2.
  • the invention comprises a pair of radiating elements M and 16 which are wound in an interrelated triangular helix up the length of the support post 10, and concentric with the axis thereof with equal and uniform longitudinal spacing between the windings, as illustrated.
  • the triangular shape will fit around the hexagonal post 10 as shown in lFlG. 2.
  • the triangles are equilateral, although this is not absolutely necessary.
  • the elements 114 and I6 will normally be copper wire, but any suitable element to provide electromagnetic radiation will meet the objects of the invention. It should be understood that the post 10 is purely for purposes of support, and that any low loss material for supporting the antenna would be used. Also, of course, if the wires themselves have sufficient strength, or if the antenna is to be used in a space environment the post 10 may not be necessary. The only requirement is that the antenna windings be concentric to some common axis.
  • the antenna of FIG. 1 was made as an experimental model.
  • the pitch angle of the triangular helices was equal to 19.5 with a design bandwidth of between 1.00 to 2.00 Ghlz.
  • the ground plane diameter established by base 12 was 10 inches.
  • the base l2 was made from a conductive material whereas the post id was made from a dielectric material.
  • the pitch angle and bandwidth would change depending upon the specific requirements of the antenna.
  • the pitch angle of the antenna elements could be continually decreasing along the structure with a similar decrease in the dimension of the triangles to form a pyramidal like antenna.
  • a structure of this type would have a broader frequency bandwidth.
  • winding 14 is in a right-hand pattern while winding i6 is in a left-hand pattern.
  • the winding 14 is thus capable of transmitting and receiving right-hand circularly polarized radiation, with the winding 16 capable of transmitting and receiving left-hand circularly polarized radiation.
  • FIG. 3 illustrates the base feed wires designated 14a and 160, respectively, and shows the vertical displacement in the right-hand circular polarization feed on line Ida to provide the predetermined pitch distance displacement.
  • the lines are actually fed from a coaxial ,cable 20 with the shield of the cable electrically connected to the ground plane.
  • the purpose of coordinating displacement and pitch angle is to hold VSWR to the lowest possible value at the junction between the coaxial cable 20 and the antennas.
  • the radiation pattern and reception pattern with respect to each of the windings l4 and 16 is a uniformly directed lobe which has much greater predictability than normal countrawound helical antennas because of the lack of mutual coupling between windings.
  • the other winding could be receiving left-hand circularly polarized signals, thus making the antenna extremely desirable for use with earth orbiting satellites, for example, where one ground station would radiate right-hand circularly polarized waves to be detected by the right-hand circularly polarized antenna on the satellite, to trigger a lefthand circularly polarized signal from the satellite to be received at the left-hand circularly polarized antenna on the earth. This can be achieved in compact relationship on the single antenna structure.
  • FIG. 4 illustrates a modified embodiment of the invention utilizing substantially a square pattern in the windings in lieu of the triangular pattern. Again the points or corners are alternately positioned to provide the greatest possible spacing to prevent mutual coupling. It is believed that a figure with any more sides than four would not meet the objects of the invention.
  • the angular relation of the radiating elements to the ground plane could vary according to the particular radiation requirements of the antenna, but that the antenna should have a ground plane, and some helical configuration to the triangular windings.
  • the antenna is an intermediate frequency bandwidth antenna transmitting and receiving with different sense polarizations at slightly different frequencies, and is quite effective for these purposes.
  • the mutual coupling between antennas' is greatly reduced because of the hexagram configuration of the antenna.
  • Proper phasing of the radiating elements 14 and to, both in space and time will provide the best operating characteristics for each construction, determined for a particular required condition.
  • An antenna which comprises:
  • At least two radiating elements wound in a geometric pattern of not more than four sides in opposed helixes along a common axis with a uniform longitudinal spacing between elements and alternate positioning of angular changes in the elements whereby maximum spacing between elements is achieved to reduce mutual coupling;
  • An antenna according to claim 1 which includes a connector for feeding the elements, where said means to form a ground plane is a base and where the connector is electrically connected to the base whereby the base provides a ground plane for the antenna.
  • An antenna according to claim 2 which includes a post to support the radiating elements, which post in cross section has the shape of a hexagon, and the shape of the elements in plan is an equilateral triangle closely fitting around the longitudinal axis of the post.
  • An antenna which comprises: a base to provide a ground plane; and a pair of elements capable of transmitting and receiving electromagnetic radiation mounted to the base and extending substantially normal thereto in concentric relation to an axis substantially perpendicular to the surface of the base which is characterized by the elements being wound in opposed triangularly shaped helical convolutions about the axis with a uniform longitudinal spacing between elements whereby each apex is associated with a corresponding base of the adjacent element to reduce mutual coupling therebetween upon energization.
  • An antenna which comprises:
  • At least two radiating elements wound in a geometric pattern of not more than four sides in opposed helixes along a common axis with uniformly decreasing longitudinal spacing between elements, with a similar uniform decrease in the size of the convolutions of each helical wrap, and with alternate positioning of angular changes in the elements whereby maximum spacing between elements is achieved to reduce material coupling;

Abstract

Two triangular radiating elements are interlaced in a helical winding about a common axis to form a single antenna structure. The elements are wound in opposite directions and are laterally separated, thus reducing the RF coupling between them and improving the circularity of each radiating pattern with one radiating element wound in one direction and the other in the opposite direction, a dual circularity is achieved from the same physical volume.

Description

I United States Patent l 13,569,977
[72] inventor William B. Koller [56] References cu d 9:3 lohio UNITED STATES PATENTS [2!] A pl. No. i 2 616 046 10/1952 Marston et al 343/895X 22 Filed Dec. 26, 1968 Patented Mar. 9, 1971 3,083,364 3/1963 .Scheldorf 343/843 [73] Assignee Goodyear Aerospace Corporation Primary ExammerEh Lieberman Akron, Ohio Assistant ExaminerMarvin Nussbaum Attorney-J. G. Pere [54] flExfscRAM ANTENNA ABSTRACT: Two triangular radiating elements are interlaced 7 Chum 4 Drawmg Figs in a helical winding about a common axis to form a single an- [52] U.S. Cl. 343/848, tenna structure. The elements are wound in opposite 343/895 directions and are laterally separated, thus reducing the RP [51] Int. (I H0lq l/36, coupling between them and improving the circularity of each HOlq l/48 radiating pattern with one radiating element wound in one [50] Field of Search 343/874, direction and the other in the opposite direction, a dual circu- 895, 843, 848 iarity is achieved from the same physical volume.
PATENTED m 9197:
lOa
FIG.-2
FlG.-4
FlG.-l
ATTORNEYS HEXAGltAli/l ANTENNA ll-lleretofore the use of helical antennas has been well known, with these antennas designed to provide a predetermined directional radiating and reception pattern. Various methods have been utilized'to achieve circularity in the patterns, and to prevent mutual RF coupling between separate radiating elements if more than one element is utilized. However, the problem of preventing mutual RP coupling, and obtaining dual circularity in one composite antenna structure is needed by the art.
Therefore, it is the general object of the invention to meet the needs of the art by providing dual circularity in radiating and reception patterns on a single radiating structure, and where mutual coupling between separate radiating elements is substantially reduced.
For a better understanding of the invention reference should be had to the accompanying drawings wherein:
FIG. 1 is a side elevational view of an antenna made according to one embodiment of the invention;
FIG. 2 is a cross-sectional plan view of the antenna of FIG. ll taken on line 2-2 thereof;
FIG. 3 is an enlarged broken away side view of the base of the antenna of FIG. 1 showing how the feed is provided to the separate radiating elements;
FIG. 4 is a cross-sectional plan viewof a second embodiment of the antenna of the present invention.
With reference to the embodiment of the invention shown in MG. l of the drawings, the numeral indicates generally an elongated supporting post having an axis which is carried by a mounting base 112 in any conventional manner so the axis is substantially normal to the surface of the base 12. The post is preferably hexagonal in cross section as seen in FIG. 2. The invention comprises a pair of radiating elements M and 16 which are wound in an interrelated triangular helix up the length of the support post 10, and concentric with the axis thereof with equal and uniform longitudinal spacing between the windings, as illustrated. The triangular shape will fit around the hexagonal post 10 as shown in lFlG. 2. Preferably, the triangles are equilateral, although this is not absolutely necessary. The elements 114 and I6 will normally be copper wire, but any suitable element to provide electromagnetic radiation will meet the objects of the invention. It should be understood that the post 10 is purely for purposes of support, and that any low loss material for supporting the antenna would be used. Also, of course, if the wires themselves have sufficient strength, or if the antenna is to be used in a space environment the post 10 may not be necessary. The only requirement is that the antenna windings be concentric to some common axis.
The antenna of FIG. 1 was made as an experimental model. The pitch angle of the triangular helices was equal to 19.5 with a design bandwidth of between 1.00 to 2.00 Ghlz. The ground plane diameter established by base 12 was 10 inches. The base l2 was made from a conductive material whereas the post id was made from a dielectric material. However, it is to be understood that the pitch angle and bandwidth would change depending upon the specific requirements of the antenna.
The pitch angle of the antenna elements could be continually decreasing along the structure with a similar decrease in the dimension of the triangles to form a pyramidal like antenna. A structure of this type would have a broader frequency bandwidth.
The unique aspect of this antenna and that critical to its proper operation is that the triangular helices are wound in opposite direction about a common axis llla, as is best illustrated in FIG. 2;. Essentially, winding 14 is in a right-hand pattern while winding i6 is in a left-hand pattern. The winding 14 is thus capable of transmitting and receiving right-hand circularly polarized radiation, with the winding 16 capable of transmitting and receiving left-hand circularly polarized radiation.
With the exception of the feed line lengths at the base of the interlacing of the two helices requires that one of them be displaced some predetermined pitch distance higher off the ground plane. This distance to achieve minimum RF coupling can be determined either experimentally or mathematically. The opposite directing of the windings in the triangular helix pattern provides the greatest actual spaced relationship between the wires so as to substantially reduce mutual coupling. Specifically, as is quite clearly shown in H6. 2, the triangnilar points of each winding M'and 16 are at considerable spaced distances from the flat bases adjacent thereto, thus providing the maximum spaced relationship possible which greatly reduces mutual coupling.
FIG. 3 illustrates the base feed wires designated 14a and 160, respectively, and shows the vertical displacement in the right-hand circular polarization feed on line Ida to provide the predetermined pitch distance displacement. The lines are actually fed from a coaxial ,cable 20 with the shield of the cable electrically connected to the ground plane. The purpose of coordinating displacement and pitch angle is to hold VSWR to the lowest possible value at the junction between the coaxial cable 20 and the antennas.
The radiation pattern and reception pattern with respect to each of the windings l4 and 16 is a uniformly directed lobe which has much greater predictability than normal countrawound helical antennas because of the lack of mutual coupling between windings. Also, it should be understood that while one winding can be operating on the right-hand circularly polarized pattern, the other winding could be receiving left-hand circularly polarized signals, thus making the antenna extremely desirable for use with earth orbiting satellites, for example, where one ground station would radiate right-hand circularly polarized waves to be detected by the right-hand circularly polarized antenna on the satellite, to trigger a lefthand circularly polarized signal from the satellite to be received at the left-hand circularly polarized antenna on the earth. This can be achieved in compact relationship on the single antenna structure.
FIG. 4 illustrates a modified embodiment of the invention utilizing substantially a square pattern in the windings in lieu of the triangular pattern. Again the points or corners are alternately positioned to provide the greatest possible spacing to prevent mutual coupling. It is believed that a figure with any more sides than four would not meet the objects of the invention.
It should be understood that the angular relation of the radiating elements to the ground plane could vary according to the particular radiation requirements of the antenna, but that the antenna should have a ground plane, and some helical configuration to the triangular windings. The antenna is an intermediate frequency bandwidth antenna transmitting and receiving with different sense polarizations at slightly different frequencies, and is quite effective for these purposes. The mutual coupling between antennas'is greatly reduced because of the hexagram configuration of the antenna. Proper phasing of the radiating elements 14 and to, both in space and time will provide the best operating characteristics for each construction, determined for a particular required condition.
While in accordance with the patent statutes, only one best known embodiment of the invention has been illustrated and described in detail, it is to be understood that the invention is not limited thereto or thereby, but that the inventive scope is defined in the appended claims.
I claim:
ll. An antenna which comprises:
at least two radiating elements wound in a geometric pattern of not more than four sides in opposed helixes along a common axis with a uniform longitudinal spacing between elements and alternate positioning of angular changes in the elements whereby maximum spacing between elements is achieved to reduce mutual coupling; and
means to form a ground plane on one end of the elements.
2. An antenna according to claim 1 which includes a connector for feeding the elements, where said means to form a ground plane is a base and where the connector is electrically connected to the base whereby the base provides a ground plane for the antenna.
3. An antenna according to claim 2 which includes a post to support the radiating elements, which post in cross section has the shape of a hexagon, and the shape of the elements in plan is an equilateral triangle closely fitting around the longitudinal axis of the post.
4. An antenna according to claim 3 where the longitudinal displacement between elements is predetermined as a portion of the pitch distance for one convolution of the helical wrap of each element to achieve minimum VSWR between the connector and the radiating elements.
5. An antenna according to claim 4 where the pitch angle of the elements is 195 and where each element has a designed bandwidth between 1.00 to 2.00 Gl-lz.
6. An antenna which comprises: a base to provide a ground plane; and a pair of elements capable of transmitting and receiving electromagnetic radiation mounted to the base and extending substantially normal thereto in concentric relation to an axis substantially perpendicular to the surface of the base which is characterized by the elements being wound in opposed triangularly shaped helical convolutions about the axis with a uniform longitudinal spacing between elements whereby each apex is associated with a corresponding base of the adjacent element to reduce mutual coupling therebetween upon energization.
7. An antenna which comprises:
at least two radiating elements wound in a geometric pattern of not more than four sides in opposed helixes along a common axis with uniformly decreasing longitudinal spacing between elements, with a similar uniform decrease in the size of the convolutions of each helical wrap, and with alternate positioning of angular changes in the elements whereby maximum spacing between elements is achieved to reduce material coupling; and
means to form a ground plane on one end of the elements.

Claims (7)

1. An antenna which comprises: at least two radiating elements wound in a geometric pattern of not more than four sides in opposed helixes along a common axis with a uniform longitudinal spacing between elements and alternate positioning of angular changes in the elements whereby maximum spacing between elements is achieved to reduce mutual coupling; and means to form a ground plane on one end of the elements.
2. An antenna according to claim 1 which includes a connector for feeding the elements, where said means to form a ground plane is a base and where the connector is electrically connected to the base whereby the base provides a ground plane for the antenna.
3. An antenna according to claim 2 which includes a post to support the radiating elements, which post in cross section has the shape of a hexagon, and the shape of the elements in plan is an equilateral triangle closely fitting around the longitudinal axis of the post.
4. An antenna according to claim 3 where the longitudinal displacement between elements is predetermined as a portion of the pitch distance for one convolution of the helical wrap of each element to achieve minimum VSWR between the connector and the radiating elements.
5. An antenna according to claim 4 where the pitch angle of the elements is 19.5* and where each element has a designed bandwidth between 1.00 to 2.00 GHz.
6. An antenna which comprises: a base to provide a ground plane; and a pair of elements capable of transmitting and receiving electromagnetic radiation mounted to the base and extending substantially normal thereto in concentric relation to an axis substantially perpendicular to the surface of the base which is characterized by the elements being wound in opposed triangularly shaped helical convolutions about the axis with a uniform longitudinal spacing between elements whereby each apex is associated with a corresponding base of the adjacent element to reduce mutual coupling therebetween upon energization.
7. An antenna which comprises: at least two radiating elements wound in a geometric pattern of not more than four sides in opposed helixes along a common axis with uniformly decreasing longitudinal spacing between elements, with a similar uniform decrease in the size of the convolutions of each helical wrap, and with alternate positioning of angular changes in the elements whereby maximum spacing between elements is achieved to reduce material coupling; and means to form a ground plane on one end of the elements.
US786911A 1968-12-26 1968-12-26 Hexagram antenna Expired - Lifetime US3569977A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US78691168A 1968-12-26 1968-12-26

Publications (1)

Publication Number Publication Date
US3569977A true US3569977A (en) 1971-03-09

Family

ID=25139922

Family Applications (1)

Application Number Title Priority Date Filing Date
US786911A Expired - Lifetime US3569977A (en) 1968-12-26 1968-12-26 Hexagram antenna

Country Status (1)

Country Link
US (1) US3569977A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5345248A (en) * 1992-07-22 1994-09-06 Space Systems/Loral, Inc. Staggered helical array antenna
US5841407A (en) * 1996-10-11 1998-11-24 Acs Wireless, Inc. Multiple-tuned normal-mode helical antenna

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2616046A (en) * 1949-12-01 1952-10-28 Arthur E Marston Multielement helix antenna
US3083364A (en) * 1958-07-23 1963-03-26 Andrew Corp Bifilar wound quarter-wave helical antenna having broadside radiation

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2616046A (en) * 1949-12-01 1952-10-28 Arthur E Marston Multielement helix antenna
US3083364A (en) * 1958-07-23 1963-03-26 Andrew Corp Bifilar wound quarter-wave helical antenna having broadside radiation

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5345248A (en) * 1992-07-22 1994-09-06 Space Systems/Loral, Inc. Staggered helical array antenna
US5841407A (en) * 1996-10-11 1998-11-24 Acs Wireless, Inc. Multiple-tuned normal-mode helical antenna

Similar Documents

Publication Publication Date Title
US4062019A (en) Low cost linear/circularly polarized antenna
US4160978A (en) Circularly polarized loop and helix panel antennas
US3940772A (en) Circularly polarized, broadside firing tetrahelical antenna
JPH0453322B2 (en)
US6172655B1 (en) Ultra-short helical antenna and array thereof
JP2003502894A (en) Multiband antenna
US6806845B2 (en) Time-delayed directional beam phased array antenna
US3771162A (en) Omnidirectional antenna
US20100019979A1 (en) Tulip antenna with tuning stub
US2812514A (en) Spiral slot antenna
US6067058A (en) End-fed spiral antenna, and arrays thereof
EP3314694B1 (en) Multi-filar helical antenna
US20110221647A1 (en) Multi-Element Folded-Dipole Antenna
JPH0746028A (en) Antenna device and transponder equipped with the same
US3932874A (en) Broadband turnstile antenna
US5264861A (en) Circular polarization antenna
US3569977A (en) Hexagram antenna
CN1663075A (en) Double polarization dual-band radiating device
US3221332A (en) Log periodic antenna with plural crossed dipoles
US3409893A (en) Zigzag radiator with panel reflector
JP2005117493A (en) Frequency sharing nondirectional antenna and array antenna
JP4133695B2 (en) Compound antenna
RU2684676C1 (en) Antenna
US4021811A (en) Quad antenna support
US4087824A (en) Asymmetrically fed antenna arrays