EP0468620B1 - Zweibandantenne mit Mehrfachausnutzung der Frequenzbänder - Google Patents

Zweibandantenne mit Mehrfachausnutzung der Frequenzbänder Download PDF

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Publication number
EP0468620B1
EP0468620B1 EP19910303892 EP91303892A EP0468620B1 EP 0468620 B1 EP0468620 B1 EP 0468620B1 EP 19910303892 EP19910303892 EP 19910303892 EP 91303892 A EP91303892 A EP 91303892A EP 0468620 B1 EP0468620 B1 EP 0468620B1
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EP
European Patent Office
Prior art keywords
meanderline
traces
layers
antenna
waveguide
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
EP19910303892
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English (en)
French (fr)
Other versions
EP0468620A3 (en
EP0468620A2 (de
Inventor
Terry M. Smith
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.)
Maxar Space LLC
Original Assignee
Space Systems Loral LLC
Loral Space Systems Inc
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 Space Systems Loral LLC, Loral Space Systems Inc filed Critical Space Systems Loral LLC
Publication of EP0468620A2 publication Critical patent/EP0468620A2/de
Publication of EP0468620A3 publication Critical patent/EP0468620A3/en
Application granted granted Critical
Publication of EP0468620B1 publication Critical patent/EP0468620B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q21/00—Antenna arrays or systems
    • H01Q21/24—Combinations of antenna units polarised in different directions for transmitting or receiving circularly and elliptically polarised waves or waves linearly polarised in any direction
    • H01Q21/245—Combinations of antenna units polarised in different directions for transmitting or receiving circularly and elliptically polarised waves or waves linearly polarised in any direction provided with means for varying the polarisation 
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q15/00—Devices for reflection, refraction, diffraction or polarisation of waves radiated from an antenna, e.g. quasi-optical devices
    • H01Q15/24—Polarising devices; Polarisation filters 
    • H01Q15/242—Polarisation converters
    • H01Q15/244—Polarisation converters converting a linear polarised wave into a circular polarised wave

Definitions

  • This invention relates to antennas having frequency reuse capabilities, and more particularly to antennas having a four port network or quadruplexer located in the antenna waveguide, a feed horn attached to the waveguide, and a polarizer disposed at the aperture of the antenna for converting linearly polarized signals to circularly polarized signals.
  • This device includes two coaxial waveguides, the outer waveguide being used for the transmission and reception of the four GHz band and the inner coaxial waveguide being utilized for the six GHz band.
  • a tunable configuration of screws and baffles within the waveguides are utilized to convert the linearly polarized signals into circularly polarized signals.
  • the device utilizes a grooved conical horn to transmit and receive signals.
  • a meanderline polarizer comprising several printed-circuit sheets each covered with an array of conductive meander lines is disclosed in a paper entitled "Polarization Converters for a DBS Flat-Plate Antenna" published as BBC Research Department Report, No. 7, July 1988. As the title of the paper suggests, the meanderline polarizer was used only for a flat-plate antenna and no other investigations were made or uses contemplated.
  • Japanese Patent Application No. A-1126803 disclosed the use of an antenna comprising a waveguide section coupled to a horn provided with a cover in the form of a meanderline polarizer.
  • the waveguide section is provided with two orthogonal ports with one being axially positioned in order to input a linearly polarized signal into the antenna.
  • the present invention provides a frequency reuse antenna comprising: a waveguide network having ports for transmitting and receiving orthogonal, linearly polarized signals of a second frequency; a feed horn being engaged to said waveguide network and adapted to enhance the transmission and reception of signals from and to said waveguide network respectively; and a signal polarizing means being engaged to the aperture of said feed horn and adapted to convert between linearly polarized signals and circularly polarized signals, characterised in that the antenna is a dual band antenna with the waveguide network having a central section and four ports, two of the ports being positioned to feed into the free end of the central section for receiving orthogonal, linearly polarized signals within a first-frequency band, and the other two of the ports being spaced apart at different axial positions along the central section near the end of the section to which the feed horn is attached whereby to transmit orthogonal linearly polarized signals within a second frequency band different to said first frequency band.
  • the meanderline polarizer (16) preferably includes five separated layers of meanderlines, wherein the first and fifth layers (50 and 58 respectively) include identical meanderlines, the second and fourth (52 and 56 respectively) layers include identical meanderlines that differ from those of the first and fifth layers, and the third layer (54) includes meanderlines that differ from the others in the first, second, fourth and fifth layers. It is an advantage of the present invention that it provides a dual band frequency reuse antenna having minimal cross-polarization.
  • the four port waveguide network is preferably constructed as a square waveguide, a pyramidal horn and meanderline polarizer to achieve increased signal gain and reduced cross-polarization. This provides dimensional stability over a broad thermal range, whereby the antenna is usable in an earth orbital environment.
  • the antenna 10 includes three main components, a waveguide 12, a horn 14 and a meanderline polarizer 16 that is attached to the aperture 17 of the horn 14.
  • the antenna 10 is preferably designed to be used with a parabolic reflector 18, such that the antenna 10 is fixedly mounted to a structure (not shown) and the antenna beam is scanned by movement of the reflector 18 relative to the fixedly mounted antenna 10.
  • the waveguide 12 includes a four port waveguide network.
  • Two of the ports 20 and 22 are designed for the transmission of orthogonal, linearly polarized signals of a first frequency, which in the preferred embodiment is a 4.035 to 4.200 GHz transmission band frequency.
  • the other two ports 24 and 26 are designed for the reception of orthogonal, linearly polarized signals of a different frequency, which in the preferred embodiment is a 6.260 to 6.425 GHz receiving band frequency.
  • the four independent, linearly polarized signals (1 from each port) are coupled into the common square waveguide 12, which in turn excites the pyramidal feed horn 14.
  • the meanderline polarizer 16 then converts the linearly polarized signals to circular polarizations, such that two oppositely, circularly polarized fields are radiated from the antenna 10 at the transmission band frequency.
  • the meanderline polarizer also converts two oppositely, circularly polarized signals to two orthogonal, linearly polarized signals at the receiving band frequency.
  • Each port 20, 22, 24 and 26 of the four port waveguide network includes an attachment flange 30, 32, 34 and 36 respectively, disposed about its outer end to which signal transmitting or receiving devices (not shown) are coupled.
  • the orthogonal ports 24 and 26 feed directly into the side and throat respectively of the waveguide 12, whereas orthogonal ports 20 and 22 are provided with additional waveguide structures 40 and 42 respectively which lead to the body of the waveguide 12.
  • the waveguide structures 40 and 42 comprise a series of rectangular corrugations formed perpendicularly to the central axis of the waveguide structures 40 and 42.
  • support straps 46 are engaged across the outer surface of the corrugations to provide structural rigidity to the waveguide structures 40 and 42.
  • the corrugated waveguide structures 40 and 42 are dimensionally configured to act as a short circuit to the six GHz signals while allowing the four GHz signals to pass therethrough.
  • the linearly polarized six GHz receiving signal does not propagate into waveguide structures 40 and 42, but rather continues through the body of the waveguide 12 to the ports 24 and 26.
  • a central section 48 of the waveguide 12 located behind ports 20 and 22 is dimensionally sized to prevent the propagation of the four GHz transmission signals backwards through the waveguide 12 to the six GHz ports 24 and 26.
  • the feed horn 14 is a pyramidal horn having a flare angle of approximately 10 degrees and a square aperture having a side measurement of approximately 6 inches; its aperture 17 is located approximately 3.5 inches towards the reflector 18 from the focal point 50 of the reflector 18.
  • the meanderline polarizer is oriented relative to the square aperture 17 of the feed horn 14, such that the meanderlines run diagonally across the aperture 17 of the feed horn 14.
  • the improved meanderline polarizer 16 serves to transform the linearly polarized signals into circularly polarized signals at the aperture 17 of the antenna horn 14.
  • the signals that propagate within the horn 14 and waveguide 12 are entirely orthogonal, linearly polarized signals, and no circularly polarized signals propagate within the horn 14 or waveguide 12. This configuration results in the transmission and reception within the waveguide of orthogonal, linearly polarized signals with significantly reduced cross-polarization, whereby improved signal gain and reduced noise is achieved.
  • the meanderline polarizer 16 is a sandwich structure including five thin layers 50, 52, 54, 56 and 58, each having a plurality of meanderline traces 60, 62, 64, 66 and 68, respectively, formed thereon.
  • Four foam-like spacers 70, 72, 74 and 76 serve to separate the five meanderline layers.
  • the use of meanderline polarizers that are generally configured as described hereinabove is well known in the art, as particularly taught in U.S. Patent 3,754,271 issued to J. Epis on August 21, 1973.
  • a significant difference between the polarizer 16 of the present invention and the prior art polarizers resides in the utilization of meanderline traces of differing dimensions in the various layers 50, 52, 54, 56 and 58.
  • the meanderline traces in layers 50 and 58 are identical
  • the meanderline traces in layers 52 and 56 are identical, although differing in dimensions from the meanderline traces in layers 50 and 58.
  • the meanderline traces in layer 54 are different in dimension from those of any other layer.
  • the polarizer is a 9.0 ⁇ square by 2.0 ⁇ thick sandwich construction.
  • the sandwich consists of the four spacers 60, 62, 64 and 66 composed of Stanthyne 817 Foam, and the five layers 50, 52, 54, 56 and 58 are composed of etched 1/2 oz. copper clad 3 mill Kapton bonded together with Hysol 9309 adhesive. Bonding is done so as not to cover the traces.
  • the polarizer is bonded to a fiberglass frame 19 which is bolted to the aperture 17 of the horn 14.
  • the traces are preferably formed on the Kapton layers utilizing printed circuit board techniques to provide close tolerances and reliability to the device.
  • the dimensions of the meanderline traces in each layer can be expressed by four parameters that are designated as: A, the periodicity of a meanderline trace; H, the height of the meanderline trace; W, the width of the meanderline trace; and B, the distance between adjacent meanderline traces.
  • A the periodicity of a meanderline trace
  • H the height of the meanderline trace
  • W the width of the meanderline trace
  • B the distance between adjacent meanderline traces.
  • the following table provides the dimensions for each of the layers of the meanderline polarizer 16.
  • the present invention provides a reuse frequency capability. That is, that the same frequency can be used for transmitting two signals, one of which is circularly polarized in a first sense and the other of which is circularly polarized in an opposite sense. Additionally, the utilization of four ports in the waveguide network permits the simultaneous utilization of two reuse frequency signals, approximately 4 GHz and approximately 6 GHz.
  • the use of a meanderline polarizer at the aperture 17 of the feed horn 14 provides improved performance as compared to prior art devices which attempt to convert signals from circular polarization to linear polarization within the waveguide.
  • the improved meanderline polarizer reduces cross-polarization and thus contributes to the improved performance of the invention.

Landscapes

  • Waveguide Aerials (AREA)
  • Aerials With Secondary Devices (AREA)
  • Control Of Motors That Do Not Use Commutators (AREA)
  • Waveguide Switches, Polarizers, And Phase Shifters (AREA)

Claims (8)

  1. Frequenz-Mehrfachnutzungs-Antenne mit:
    einem Wellenleiter-Netz (12) mit Anschlüssen zum Senden und Empfangen orthogonaler, linear polarisierter Signale einer zweiten Frequenz;
    einem an dem Wellenleiternetz (12) in Anlage gebrachten Einspeisehorn (14), das ausgelegt ist, das Senden und Empfangen von Signalen von dem Wellenleiternetz (12) bzw. durch dasselbe zu verbessern; und
    einem Signalpolarisationsmittel (16), das an der Apertur (17) des Speisehorns (14) in Anlage gebracht und ausgelegt ist, zwischen linear polarisierten Signalen und zirkular polarisierten Signalen zu wandeln,
    dadurch gekennzeichnet, daß die Antenne eine Doppelbandantenne ist, bei der das Wellenleiternetz (12) einen Zentralabschnitt und vier Anschlüsse (20, 22, 24, 26) besitzt, von denen zwei Anschlüsse (24, 26) zum Einspeisen in das freie Ende des Zentralabschnitts angeordnet sind zum Empfangen von orthogonalen linear polarisierten Signalen innerhalb eines ersten Frequenzbandes und die anderen beiden (20, 22) Anschlüsse mit Abstand voneinander an unterschiedlichen axialen Positionen längs des Zentralabschnitts in der Nähe des Abschnittendes angebracht sind, an dem das Einspeisehorn (14) angebracht ist, um dadurch orthogonale linear polarisierte Signale innerhalb eines zweiten, zum ersten Frequenzband unterschiedlichen Frequenzbandes zu senden.
  2. Doppelband-Frequenzmehrfachnutzungs-Antenne, wie in Anspruch 1 beschrieben, bei der das Signalmittel (16) einen Mäanderleitungs-Polarisator umfaßt.
  3. Doppelband-Frequenzmehrfachnutzungs-Antenne, wie in Anspruch 2 beschrieben, bei der der Maanderleitungs-Polarisator eine Vielzahl von Schichten (50, 52, 54, 56, 58) umfaßt, von denen jede Schicht eine Vielzahl von im wesentlichen identischen Mäanderleitungs-Spuren (60, 62, 64, 66, 68) umfaßt, die daran ausgebildet sind.
  4. Doppelband-Frequenzmehrfachnutzungs-Antenne, wie in Anspruch 3 beschrieben, bei der die Mäanderleitungs-Spuren (60, 62), die an mindestens zwei (50, 52) der Schichten ausgebildet sind, mit unterschiedlichen Maßen ausgebildet sind.
  5. Doppelband-Frequenzmehrfachnutzungs-Antenne, wie in Anspruch 4 beschrieben, bei der die an einer ersten Schicht (50) ausgebildeten Mäanderleitungs-Spuren (60) sich in ihren Abmessungen von den an einer zweiten Schicht (52) ausgebildeten Mäanderleitungs-Spuren (62) unterscheiden, und die an einer dritten Schicht (54) ausgebildeten Mäanderleitungs-Spuren (64) sich in ihren Abmessungen von den jeweils an der ersten Schicht (50) und der zweiten Schicht (52) ausgebildeten Mäanderleitungs-Spuren (60, 62) unterscheiden.
  6. Doppelband-Frequenzmehrfachnutzungs-Antenne, wie in Anspruch 3 beschrieben, bei der der Mäanderleitungs-Polarisator fünf Schichten (50, 52, 54, 56, 58) enthält, von denen jede Schicht eine Vielzahl von daran ausgebildeten Mäanderleitungs-Spuren (60, 62, 64, 66, 68) enthält;
    wobei die an der ersten und der fünften Schicht (50, 58) ausgebildeten Mäanderleitungs-Spuren im wesentlichen in ihren Abmessungen identisch sind;
    die an der zweiten und der vierten Schicht (52, 56) ausgebildeten Mäanderleitungs-Spuren im wesentlichen in ihren Abmessungen identisch sind, wobei sich die an der zweiten und der vierten Schicht ausgebildeten Mäanderleitungs-Spuren in ihren Abmessungen von den an der ersten und fünften Schicht ausgebildeten Mäanderleitungs-Spuren unterscheiden; und
    die an der dritten Schicht (54) ausgebildeten Mäanderleitungs-Spuren sich in ihren Abmessungen von denen an der ersten, zweiten, vierten und fünften Schicht ausgebildeten Mäanderleitungs-Spuren unterscheiden.
  7. Doppelband-Frequenzmehrfachnutzungs-Antenne nach einem der vorangehenden Ansprüche, bei der der zentrale Abschnitt des Wellenleiternetzes (12) und das Horn (14) im wesentlichen quadratische Querschnitte besitzen.
  8. Doppelband-Frequenzmehrfachnutzungs-Antenne nach einem der vorangehenden Ansprüche, die weiter umfaßt erste und zweite gewellte Wellenleiterstrukturen (40, 42) mit jeweils einer zentralen Achse und mit Wellungen, die senkrecht zur entsprechenden zentralen Achse ausgebildet sind zum Kurzschließen von Signalen des ersten Frequenzbandes, währens sie das Durchleiten von Signalen des zweiten Frequenzbandes zulassen, wobei die gewellten Wellenleiterstrukturen (40, 42) zwischen den zentralen Abschnitten und den anderen beiden Teilen (20, 22) des Wellenleiternetzes gekoppelt sind.
EP19910303892 1990-07-26 1991-04-30 Zweibandantenne mit Mehrfachausnutzung der Frequenzbänder Expired - Lifetime EP0468620B1 (de)

Applications Claiming Priority (2)

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US55903490A 1990-07-26 1990-07-26
US559034 1990-07-26

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EP0468620A2 EP0468620A2 (de) 1992-01-29
EP0468620A3 EP0468620A3 (en) 1992-05-20
EP0468620B1 true EP0468620B1 (de) 1995-12-27

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EP (1) EP0468620B1 (de)
JP (1) JP2651962B2 (de)
CA (2) CA2041572C (de)
DE (1) DE69115783T2 (de)

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Publication number Priority date Publication date Assignee Title
JPH08139502A (ja) * 1994-11-14 1996-05-31 Nec Corp 円偏波発生器
WO2009110755A2 (ko) * 2008-03-05 2009-09-11 주식회사 인텔리안테크놀로지스 반사경 안테나 및 혼 안테나을 이용한 다중 대역 신호 송/수신 장치 및 그 방법
CN107093802B (zh) * 2017-03-20 2019-07-23 东南大学 口径面相位和幅度均匀分布的高增益透镜天线
US10665931B2 (en) 2017-08-01 2020-05-26 Lockheed Martin Corporation Waveguide aperture design for geo satellites
CN114709622B (zh) * 2022-03-31 2024-04-23 重庆邮电大学 一种基于超表面结构的极化单元、极化转换器和制备方法

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3754271A (en) * 1972-07-03 1973-08-21 Gte Sylvania Inc Broadband antenna polarizer
DE3023562C2 (de) * 1980-06-24 1982-10-28 Siemens AG, 1000 Berlin und 8000 München Einrichtung zur Polarisationsumwandlung elektromagnetischer Wellen
FR2488055A1 (fr) * 1980-07-31 1982-02-05 Thomson Csf Transducteur d'antenne pour antenne d'emission-reception et source primaire d'antenne equipee d'un tel transducteur
FR2529392B1 (fr) * 1982-06-25 1985-06-28 Thomson Csf Dispositif de multiplexage pour grouper deux bandes de frequences et multiplexeur comportant un tel dispositif
JPS60176302A (ja) * 1984-02-22 1985-09-10 Mitsubishi Electric Corp 偏分波器
JPH0611085B2 (ja) * 1987-02-23 1994-02-09 三菱電機株式会社 円偏波アレ−アンテナ
JPH01126803A (ja) * 1987-11-12 1989-05-18 Mitsubishi Electric Corp ホーンアンテナ装置

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DE69115783T2 (de) 1996-07-25
JP2651962B2 (ja) 1997-09-10
JPH05136624A (ja) 1993-06-01
EP0468620A3 (en) 1992-05-20
CA2046975A1 (en) 1992-01-27
CA2041572A1 (en) 1992-01-27
CA2041572C (en) 1999-11-09
DE69115783D1 (de) 1996-02-08
EP0468620A2 (de) 1992-01-29

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