US2928087A - Omnidirectional beacon antenna - Google Patents

Omnidirectional beacon antenna Download PDF

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Publication number
US2928087A
US2928087A US678938A US67893857A US2928087A US 2928087 A US2928087 A US 2928087A US 678938 A US678938 A US 678938A US 67893857 A US67893857 A US 67893857A US 2928087 A US2928087 A US 2928087A
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United States
Prior art keywords
elements
carrier
coupling
rotating
radius
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Expired - Lifetime
Application number
US678938A
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English (en)
Inventor
Ernest G Parker
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.)
TDK Micronas GmbH
International Telephone and Telegraph Corp
Original Assignee
Deutsche ITT Industries GmbH
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Publication date
Application filed by Deutsche ITT Industries GmbH filed Critical Deutsche ITT Industries GmbH
Priority to US678938A priority Critical patent/US2928087A/en
Priority to GB26295/58A priority patent/GB842063A/en
Priority to CH6300058A priority patent/CH364535A/de
Application granted granted Critical
Publication of US2928087A publication Critical patent/US2928087A/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
    • H01Q3/00—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system
    • H01Q3/12—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system using mechanical relative movement between primary active elements and secondary devices of antennas or antenna systems
    • H01Q3/14—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system using mechanical relative movement between primary active elements and secondary devices of antennas or antenna systems for varying the relative position of primary active element and a refracting or diffracting device
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S1/00—Beacons or beacon systems transmitting signals having a characteristic or characteristics capable of being detected by non-directional receivers and defining directions, positions, or position lines fixed relatively to the beacon transmitters; Receivers co-operating therewith
    • G01S1/02—Beacons or beacon systems transmitting signals having a characteristic or characteristics capable of being detected by non-directional receivers and defining directions, positions, or position lines fixed relatively to the beacon transmitters; Receivers co-operating therewith using radio waves

Definitions

  • This invention relatesto omnidirectional beacon antennas and more particularly toomnidirectional beacon antennas for use in producing ay multilobed radiation pattern having afundamental modulation frequency and one or more Aadditional harmonicsv of the fundamental frequency for use in radio navigation systems suchas that commonly known as TACAN, j Y Y Omnidirectional beacon systems such as in TACAN have a high order of directional accuracy which is dependent upon the :use of a directive antenna pattern rotatedat a, fundamental#frequencyV and modulated by a harmonic of fundamental frequency so.
  • the ⁇ principal object ofthis invention isto provide an omnidirectional' beacon antenna,lhayin'g, af small height and diameter' while Qbtiliniug high carrier ⁇ vgain in the vertical pattern ⁇ and good; modulation characteristics.
  • parasitic modulating elements are spaced less than three ⁇ half Wave-f lengths from the center, either along the same radiusas the carrier elements or equally spaced between the carrier elements.
  • the harmonic modulation component is the ninth harmonic, it is preferred to use nine parasitic modulating elements and nine rotating carrier elements.
  • the elements may be quarter-wavelength elements onV a counterpoise or they may be half-wavelength center fed elements. ,Y ,i A
  • the means for coupling energy to the rotating carrier elements rincludes vertical coupling elements spaced near the. center element.
  • these coupling elements are connected at the .upper endvby .a coupling ring and the lower end is adjacent the counterpoise and connected to the transmissionline.
  • the rotating carrier elements may be folded monopoles.
  • the transmission line is coupled between the centers of the' coupling elements and the centers of the rotating carrier elements, and the upper and lower edsgof the, coupling elements are connected by coupling rings.
  • the rotating carrier elements may be folded dipoles.
  • Fig. 3 is a plan view of an embodiment using hlf- Wavele'ngth elements
  • Fig. 4 is a cross-section View taken along lines 3 3 of'Fig. 4;
  • Fig. 5 is a diagram in perspective useful in explaining the formation of the radiation pattern
  • Fig. 6 is a vector diagram of the radiation components
  • Fig 7 is a graph of two Bessel coeicients of the radiation components used in the analysis.
  • Figs. 8 and 9 are computed and measured graphs respectively of the variation of carrier signal strength with elevation angle. Y
  • an Vomnidiiectional beacon antenna having a central quarter-wavelength radiating element 1 in the form of a cup, rotating carrier elements 2, a fundamental parasitic element 4a, and harmonic parasitic elements 4.
  • the center element is supported by insulation 5 above a counterpoise 6, and the rotating elements 2, 3, and 4 are mounted on a counterpoise 7.
  • the center stationary portion of the counterpoise has a skirt portion 8 and the rotating portion has a skirt portion 9, the skirts being a quarter-wavelength long forming' an R-F choke joint.
  • the rotating'counte'rpoise 7 is mounted on a supporting structure shown diagrammatically at 10 which is rotated by a motor 11.
  • a coaxial feedline 12 passes through the hollow shaft of the motor.
  • Line 12 has its center conductor 13 connected to the center radiating element 1 and its outer conductor 14 connected to the stationary counterpoise 6.
  • the elements 2 are yfed by a transmission line 3 which is spaced from the counterpoise 7 by a spacer 15, which may be balsa wood. These transmission lines are connected, respectively, at their inner ends to vertical coupling elements 16. The upper ends of these elements 16 are connected by a ring 17 which is supported by a dielectric cylinder 18. The elements 2 are folded monopoles to match the impedance of the transmission lines 3.
  • the center radiator has a radius of 1%/4 inches
  • the cupling elements 16 are at a radius of 2%; inches
  • the rotating carrier elements 2 have their inner wire at a radius of 91%6 inches and their outer wire at a radius dk of l inches.
  • the parasitic elements 4 are at a radius dm of 12 inches.
  • the rotating elements and transmission line are formed from #18 A.W.G. wire.
  • An embodiment using printed half-wavelength elements includes a stationary central radiator in the form of two cups 19 and 2t) fed by a transmission line 21.
  • the inner conductor 22 of line 21 is connected to the upper portion 19 of the dipole and the outer conductor 22 is connected to the lower portion 23.
  • the rotating portion 20 of the antenna includes carrier elements 24 and parasitic elements 25.
  • the carrier elements 24 are in the form of folded dipoles fed by respective transmission lines 26, which are connected at their inner ends to the centers of respective vertical coupling elements 27. These coupling elements 27 are connected at their upper ends by a coupling ring 28 and at their lower ends by a coupling ring 29.
  • the elements 24, 25 and 27 and lines 26 are printed on respective supports 30, which are mounted on a dielectric cylinder 31.
  • a fundamental parasitic element 32 is mounted on an inner surface of cylinder 31.
  • Cylinder 31 may be mounted on a rotating counterpoise 33.
  • This counterpoise 33 has an inner skirt 34 and an outer skirt 35 which are a quarter wavelength and form R-F choke joints.
  • the rotating assembly may be supported and driven by a structure such as that shown diagrammatically in Fig. 2.
  • the coupling elements 27 have a radius of 21/2 inches, the outer conductor of elements 24 is at a radius of inches, and the parasitic elements 25 are at a radius of 13 inches.
  • the transmission lines 26 have the conductors spaced 1%6 inch and are mounted 5 inches above the counterpoise.
  • the inner and outer conductors of the elements 24 are spaced 3A; inches.
  • the vertical length of the elements 24 and 25 may be 4 inches.
  • Fig. 5 is a diagram in perspective of one rotating element at a distance d from a center element.
  • the received signal will include a component C from the center element and a component R from the rotating element.
  • Fig. 6 is a simple vector diagram of the radiated signals.
  • the center element radiates a carrier signel KC.
  • the rotating element will produce a signal having two components KR and MR which are always in quadrature.
  • the relative radiation phase if of KR with respect to KC depends upon the factors including the relative excitation phase and the phase angle of self-impedance of the clements.
  • Analysis using the Bessel function expansion shows that the component KR includes a carrier component and all even harmonic modulation components of 0, and the component MR contains all the odd harmonic terms.
  • a carrier radio frequency equal to WK/Znthe resulting eld pattern at the distant point may be given by the following equation:
  • MR 18Q RnB) Jgd es B) cos 9 o
  • KR 9a fR(B) J0(d cos B)
  • Kc is a function fc(B) of the vertical angle
  • J0 (d cos B) is the Bessel term of order zero and argument (d cos B)
  • I9(d cos 0) is the Bessel term of order nine and argument (d cos B).
  • the constant a depends on the relative signal strength from. the rotating and center elements.
  • the expressions fR(B) and fC(B) are the space factors, or vertical patterns, of the individual rotating and center elements, respectively. If the angular rate of rotation elements about the central elements is wM, and p is the bearing angle to the receiver, then 0 is equal to (wMt-).
  • the relative radiation phase ⁇ If should be centered around an odd integral number of 90, that is mr/ 2 with n an integer.
  • the excitation phase with parasitic rotating elements is the spacing d in electrical distance. If the self-impedance phase is set equal to zero, the proper radiation phase for maximum modulation occurs at the odd numbers of quarter wavelength for the spacing d.
  • the values of these odd integers may be referred to as modes.
  • FIG. 7 A graph of the J0 and J9 Bessel coecient terms, according to wavelength and radians, is given in Fig. 7.
  • the variation of the Bessel coefficient with vertical angle (d cos B) for any value of d may be obtained as indicated on the graph for eleven radians.
  • a maximum in the J9 curve occurs near eleven radians, which is in the seventh mode, and this spacing has often been chosen for parasitic modulating elements in previous antenna designs. At this spacing, the J9 term decreases as the vertical angle increases, the value at 35 being shown on the graph.
  • Fig. 7 An inspection of Fig. 7 shows that ninth harmonie modulation may be obtained in the fifth mode, and that the carrier term J0 could be used to obtain gain if the correct phasing were used. Further, thes lope of I0 which occurs from about four to seven radians has a desirable slope such that for spacings of about seven radians, the value decreases as the vertical angle increases.
  • Fig. 8 is a calculated pattern using half-wave elements in free space at a radius of 61/2 radians.
  • the curve Kc is the pattern, or space factor, for a half-wave center element.
  • KR is the variation vof the Bessel term Io. The sum of these terms if added in phase is shown by the curve Kyi-KR. This curve is seen to predict high gain at low angles, dropping to a very low value at about 50. Since the curve KR does not take into consideration the space factor of the rotating element, the second lobe predicted by the curve Kc-l-KR should be very minor. Experimental results from a model using a spacing of 7.5 radians are shown by the curve in Fig. 9.
  • a counterpoise or ground plane will modify the patterns shown in Figs. 8 and9 by producing uptilt, so that the maximum carrier radiation occurs above Zero degrecs, or the horizon.
  • Figs. l to 4 use a radius of one wavelength at a frequency near the centerrof the band for the carrier elements.
  • the quadrature radiation component from the carrier elements will produce a small amount of ninth harmonic modulation.
  • vIt is-necessary to supplement this by using parasitic elements at a spacing at which the .T9 term is greater, and which.. have the proper radiation phase. These elements maybe placed at about 8.5 radians, and either in line with the carrier elements or on radii midway between them.
  • the .T9 curve in the fifth mode has a slope which produces a vertical pattern which approximates the slope ofthe resulting carrier pattern, thereby' producing relative modulation within the desired limits at vertical angles up to a high value.
  • an antenna is designed for operation in the fifth mode, with rotating carrier elements having positive feed in phase with the center radiator.
  • Such an antenna has a small diameter and small vertical height, and the desirable characteristics of large diameter antennas with a vertically stacked central array.
  • additional carrier elements may be used at greater radii to obtain still more gain, if proper points on the L, curve for the desired slope ane chosen, and the phasing is correct.
  • An omnirange beacon antenna system comprising a vertically disposed vertically polarized central radiator, a verticallyI polarized carrier element vertically disposed for rotation about said central radiator, means for supporting said carrier element, means to rotate said supporting means, a source of input energy, rst Itransmission line means coupling radio-frequency energy from said source to said central radiator, and means for coupling energy from said source to said carrier element to obtain a radient-energy pattern having gain in the average value at low angles in the vertical planes.
  • An antenna system according to claim l, further including a parasitic element mounted on said supporting means for rotation about said central radiator to produce a modulation component in said radiant-energy pattern.
  • An antenna system including a plurality of said carrier elements, and further including a plurality of parasitic elements mounted on said supporting means for rotation about said central radiator to produce modulation in said radiant-energy pattern.
  • An antenna system comprising a vertically disposed vertically polarized central radiator, a vertically polarized carrier element vertically disposed for rotation about said cen-tral'radiator, means for supporting said carrierelement, and means to rotate said supporting means, a source of input energy, rst transmission line means coupling energy from said source to said central radiator, and means including second transmission line means forcoupling energy from said source to said carrier'eler'nent to obtain a radiant-energy pattern havingrgain in the average value at low angles inthe vertical planes.
  • said means f or coupling energy to said carrier element in cludes a vertically disposed coupling element mounted on said supporting means at a small radius compared to the radius to said carrier element, and said second transmission line couples said coupling element to said carrier element.
  • An antenna system further including a parasitic element mounted on said supporting means for rotation about said central radiator to produce a modulation component in said radiant-energy pattern.
  • An antenna system including .la plurality of said carrier elements, and further including a plurality of parasitic elements mounted on said supporting means for rotation about said central radiator to produce modulation in said radiant-energy pattern.
  • An antenna system wherein said energy may be at any frequency within a Agiven band, and said rotating carrier and parasitic elements are located at a radius of less than three half wavelengths at a frequency within said band.
  • An antenna system wherein said supporting means and the elements mounted thereon are rotated at a given angular velocity, there being n said carrier elements equally spaced around a circumference at a radius of approximately one wavelength, said plurality of parasitic elements comprising one element for modulation at said angular velocity and a group of n. elements equally spaced around a circumference at a radius greater than one wavelength for producing modulation at the nth harmonic of said angular velocity.
  • An omnirange beacon antenna system comprising a vertically disposed vertically polarized central radiator, an outer vertically polarized element vertically disposed for rotation about said central radiator, means for supporting said outer element, means to rotate said supporting means, a source of input energy, first'transmission line means coupling radio-frequency energy from said source to said central radiator, and means including second transmission line means for coupling energy from said source to said outer element.
  • An antenna system comprising a vertically disposed vertically polaiized central radiator, supporting means, means to rotate said supporting means, a source of radio-frequency energy within a given frequency band, means coupling energy from said source to said central radiator, n carrier elements mounted on said supporting means equally spaced around a circumference at a radius from the center of the central radiator of less than three half wavelengths at a frequency within said band, n vertically disposed coupling elements mounted on said supporting means around a circumference at a small radius compared to the radius to said outer elements; a coupling ring connected to an end of each of said coupling elements, n transmission lines, each coupling one of said coupling elements to a corresponding one of said carrier elements, said antenna system having a radiantenergy pattern such that at a remote point at a low vertical angle it has substantial gain in the average value with respect to the central radiator pattern.
  • An antenna system comprising a vertically disposed vertically polarized central radiator, supporting means, means to rotate said supporting means at a given angular velocity, a source of radio-frequency energy within a given frequency band, means coupling energy from said source to said central radiator, n carrier elements mounted on said supporting means equally spaced around a circumference at a radius from the center of the central radiator of less than three half wavelengths at a frequency Within said band, n.
  • each of said coupling elements mounted on said supporting means around a circumference at a small radius compared to the radius to said outer elements, a coupling ring connected to an end of each of said coupling elements, n transmission lines, each coupling one of said coupling elements to a corresponding one of said carrier elements, and n parasitic elements equally spaced around a circumference at a radius of less than three half wavelengths at a frequency within said band, said antenna system having a radiant-energy pattern such that at a remote point at a low vertical angle it has substantial gain in the including a counterpoise, said central radiator, carrierelements and parasitic elements being quarter-Wavelength elements disposed above said counterpoise, and said transmission lines comprise respective conductors parallel to said counterpoise, each connected to a corresponding coupling element and carrier element.
  • An antenna system further including a counterpoise, with said central radiator, coupling elements, carrier elements, and parasitic elements spaced above said counter-poise.

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
  • Variable-Direction Aerials And Aerial Arrays (AREA)
  • Details Of Aerials (AREA)
US678938A 1957-08-19 1957-08-19 Omnidirectional beacon antenna Expired - Lifetime US2928087A (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
US678938A US2928087A (en) 1957-08-19 1957-08-19 Omnidirectional beacon antenna
GB26295/58A GB842063A (en) 1957-08-19 1958-08-15 Omnidirectional beacon antenna
CH6300058A CH364535A (de) 1957-08-19 1958-08-16 Allrichtungs-Bakenantennenanlage

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US678938A US2928087A (en) 1957-08-19 1957-08-19 Omnidirectional beacon antenna

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Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3051951A (en) * 1957-09-11 1962-08-28 Itt Omnidirectional beacon antenna
US3066291A (en) * 1960-06-20 1962-11-27 Alford Andrew Antenna structure and system
US3109175A (en) * 1960-06-20 1963-10-29 Lockheed Aircraft Corp Rotating beam antenna utilizing rotating reflector which sequentially enables separate groups of directors to become effective
US3136996A (en) * 1960-10-13 1964-06-09 Itt Omnirange beacon antenna
US3178713A (en) * 1961-03-08 1965-04-13 Andrew Corp Parabolic antenna formed of curved spaced rods
DE2523919A1 (de) * 1974-06-03 1975-12-18 E Systems Inc Antenne
USH605H (en) 1986-02-03 1989-03-07 The United States Of America As Represented By The Secretary Of The Air Force Multi-element adaptive antenna array
US4864320A (en) * 1988-05-06 1989-09-05 Ball Corporation Monopole/L-shaped parasitic elements for circularly/elliptically polarized wave transceiving
US6606057B2 (en) * 2001-04-30 2003-08-12 Tantivy Communications, Inc. High gain planar scanned antenna array
US20040027304A1 (en) * 2001-04-30 2004-02-12 Bing Chiang High gain antenna for wireless applications
US20100104054A1 (en) * 2008-10-23 2010-04-29 Troll Systems Corporation Directional diversity receive system
US20140299733A1 (en) * 2013-04-09 2014-10-09 Wistron Neweb Corporation Antenna rotation mechanism
CN118232011A (zh) * 2024-05-23 2024-06-21 成都核心智慧科技有限公司 一种基于奇偶模原理的全向和定向方向图可重构天线

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4071847A (en) * 1976-03-10 1978-01-31 E-Systems, Inc. Radio navigation antenna system
US4074268A (en) * 1976-06-21 1978-02-14 Hoffman Electronics Corporation Electronically scanned antenna
GB2438245B (en) * 2006-05-18 2010-05-05 Deltenna Ltd Antenna element

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR797676A (fr) * 1935-11-14 1936-05-01 Appareil de protection contre les gaz, avec admission d'air périphérique

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR797676A (fr) * 1935-11-14 1936-05-01 Appareil de protection contre les gaz, avec admission d'air périphérique

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3051951A (en) * 1957-09-11 1962-08-28 Itt Omnidirectional beacon antenna
US3066291A (en) * 1960-06-20 1962-11-27 Alford Andrew Antenna structure and system
US3109175A (en) * 1960-06-20 1963-10-29 Lockheed Aircraft Corp Rotating beam antenna utilizing rotating reflector which sequentially enables separate groups of directors to become effective
US3136996A (en) * 1960-10-13 1964-06-09 Itt Omnirange beacon antenna
US3178713A (en) * 1961-03-08 1965-04-13 Andrew Corp Parabolic antenna formed of curved spaced rods
DE2523919A1 (de) * 1974-06-03 1975-12-18 E Systems Inc Antenne
US3935576A (en) * 1974-06-03 1976-01-27 E-Systems, Inc. Broadband beacon antenna system
USH605H (en) 1986-02-03 1989-03-07 The United States Of America As Represented By The Secretary Of The Air Force Multi-element adaptive antenna array
US4864320A (en) * 1988-05-06 1989-09-05 Ball Corporation Monopole/L-shaped parasitic elements for circularly/elliptically polarized wave transceiving
US6606057B2 (en) * 2001-04-30 2003-08-12 Tantivy Communications, Inc. High gain planar scanned antenna array
US20040027304A1 (en) * 2001-04-30 2004-02-12 Bing Chiang High gain antenna for wireless applications
US6864852B2 (en) 2001-04-30 2005-03-08 Ipr Licensing, Inc. High gain antenna for wireless applications
US20050212714A1 (en) * 2001-04-30 2005-09-29 Ipr Licensing, Inc. High gain antenna for wireless applications
US7088306B2 (en) 2001-04-30 2006-08-08 Ipr Licensing, Inc. High gain antenna for wireless applications
US20100104054A1 (en) * 2008-10-23 2010-04-29 Troll Systems Corporation Directional diversity receive system
US8816933B2 (en) * 2008-10-23 2014-08-26 Troll Systems Corporation Directional diversity receive system
US20140299733A1 (en) * 2013-04-09 2014-10-09 Wistron Neweb Corporation Antenna rotation mechanism
US9673505B2 (en) * 2013-04-09 2017-06-06 Wistron Neweb Corporation Antenna rotation mechanism
CN118232011A (zh) * 2024-05-23 2024-06-21 成都核心智慧科技有限公司 一种基于奇偶模原理的全向和定向方向图可重构天线

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CH364535A (de) 1962-09-30
GB842063A (en) 1960-07-20

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