EP0290844B1 - Directional antenna - Google Patents

Directional antenna Download PDF

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Publication number
EP0290844B1
EP0290844B1 EP88106532A EP88106532A EP0290844B1 EP 0290844 B1 EP0290844 B1 EP 0290844B1 EP 88106532 A EP88106532 A EP 88106532A EP 88106532 A EP88106532 A EP 88106532A EP 0290844 B1 EP0290844 B1 EP 0290844B1
Authority
EP
European Patent Office
Prior art keywords
directional antenna
horn
opening
conductive disc
antenna according
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
EP88106532A
Other languages
German (de)
French (fr)
Other versions
EP0290844A3 (en
EP0290844A2 (en
Inventor
Heinrich Dipl.-Ing. Otters
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.)
Bosch Telecom GmbH
Original Assignee
ANT Nachrichtentechnik GmbH
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 ANT Nachrichtentechnik GmbH filed Critical ANT Nachrichtentechnik GmbH
Publication of EP0290844A2 publication Critical patent/EP0290844A2/en
Publication of EP0290844A3 publication Critical patent/EP0290844A3/en
Application granted granted Critical
Publication of EP0290844B1 publication Critical patent/EP0290844B1/en
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
    • H01Q13/00—Waveguide horns or mouths; Slot antennas; Leaky-waveguide antennas; Equivalent structures causing radiation along the transmission path of a guided wave
    • H01Q13/02—Waveguide horns
    • H01Q13/0266—Waveguide horns provided with a flange or a choke
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q19/00—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic
    • H01Q19/06—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using refracting or diffracting devices, e.g. lens
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q19/00—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic
    • H01Q19/10—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using reflecting surfaces
    • H01Q19/18—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using reflecting surfaces having two or more spaced reflecting surfaces
    • H01Q19/19—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using reflecting surfaces having two or more spaced reflecting surfaces comprising one main concave reflecting surface associated with an auxiliary reflecting surface

Definitions

  • the present invention relates to a directional antenna which consists of a main reflector, a horn at its base and a sub-reflector which deflects the radiation emitted by the horn towards the main reflector.
  • Directional antennas which usually consist of a horn, a main reflector and a subreflector, find e.g. Application in terrestrial radio relay, in radio location or in satellite radio.
  • Such directional antennas are sometimes required to be non-rotationally symmetrical - e.g. generate an elliptical radiation field, which is particularly important in satellite radio in order to illuminate asymmetrical regions on earth. In such cases, measures must be taken when designing a directional antenna to influence the shape of its radiation field.
  • the exciter in a directional antenna known from DE-A 30 07 150, so that it generates an elliptical radiation field, the exciter is provided with slots and a dielectric tube attached to its inner wall, which projects beyond the exciter opening and covers the slots. Also to generate an elliptical radiation field is a horn with an antenna resulting from DE-A-29 39 562 an elliptical aperture. Horn emitters with an elliptical aperture, however, have certain manufacturing problems.
  • a directional antenna with a main and a subreflector is known from AW LOVE "Reflector Antennas", Part IV: “Microwave Antennas Derived from the Cassegrain Telescope", 1978, Institute of Electrical and Electronics Engineers, US, p. 144
  • Main reflector is arranged in front of a horn.
  • the area of the main reflector located in front of the horn is designed as a grating, which has the function of a polarization filter. It transmits waves of a certain polarization direction, whereas waves of a polarization direction orthogonal to it are reflected.
  • the invention is based on the object of specifying a directional antenna which has means which are simple to manufacture in terms of production technology and which are able to give the radiation field of the antenna a desired shape.
  • a directional antenna which consists of a main reflector 1, a horn antenna 2 located at the base thereof and a subreflector 3 which deflects the radiation emitted by the horn antenna 2 towards the main reflector 1.
  • a conductive disk 4 is arranged in its radiation field, which has an opening 5 which is at least as large as the aperture of the horn 2.
  • This disk 4 influences the shape of the radiation field emanating from the horn radiator 2, depending on how the size and shape of the opening 5 in the disk 4 are selected and how far the disk 4 is from the horn aperture.
  • the opening 5 in the disc 4 is, for example, elliptical in order to give the rotationally symmetrical radiation field emanating from the round horn radiator the shape of an ellipse.
  • the angle of the radiation in the plane of the small ellipse axis decreases, whereas the angle of the radiation in the plane of the large ellipse axis remains unaffected. So you can, despite the use of a round horn, the is easy to manufacture in terms of production technology, generate an asymmetrical radiation field.
  • Other non-rotationally symmetrical opening cross sections forming the radiation field are also possible, for example rectangular, diamond-shaped etc.
  • a disc with a rotationally symmetrical (round) opening cross section in front of a circular horn has the advantageous effect that the slope of the flank of the primary characteristic becomes very steep outside the transmission angle range of the disc. This means that the unwanted subreflector radiation is disproportionately damped. Since the beam angle reduction is frequency-dependent, the natural frequency dependency of the lobe width of the horn can be compensated and the reflector can thus be illuminated as a function of frequency.
  • two or more conductive discs can also be arranged in parallel, the mutual spacings and opening cross sections of which must be selected such that the desired influence on the radiation field is achieved becomes.
  • the conductive disc 4 it is expedient to design the conductive disc 4 so curved (see FIG. 1) that any rays reflected thereon do not fall concentrated on the main reflector 1, but are scattered at a wide angle.
  • an absorber material By coating the conductive disc 4 with an absorber material, disturbing beam reflections can be reduced.
  • Holding struts 6 are provided as fastening means for the pane 4, which are attached to the edge of the horn 2 and are connected to the pane 4.

Landscapes

  • Waveguide Aerials (AREA)
  • Aerials With Secondary Devices (AREA)

Description

Die vorliegende Erfindung betrifft eine Richtantenne, die aus einem Hauptreflektor, einem in deren Fußpunkt befindlichen Hornstrahler und einem Subreflektor besteht, der die vom Hornstrahler abgegebene Strahlung zum Hauptreflektor hin umlenkt.The present invention relates to a directional antenna which consists of a main reflector, a horn at its base and a sub-reflector which deflects the radiation emitted by the horn towards the main reflector.

Richtantennen, die in der Regel aus einem Hornstrahler, einem Hauptreflektor und einem Subreflektor bestehen, finden z.B. Anwendung im terrestrischen Richtfunk, in der Funkortung oder im Satellitenfunk. Von solchen Richtantennen wird manchmal verlangt, daß sie ein nicht rotationssymmetrisches - z.B. ein elliptisches - Strahlungsfeld erzeugen, was insbesondere beim Satellitenfunk von Bedeutung ist, um asymmetrische Gebiete auf der Erde auszuleuchten. In diesen Fällen müssen also beim Entwurf einer Richtantenne Maßnahmen ergriffen werden, um Einfluß auf die Form ihres Strahlungsfeldes zu nehmen.Directional antennas, which usually consist of a horn, a main reflector and a subreflector, find e.g. Application in terrestrial radio relay, in radio location or in satellite radio. Such directional antennas are sometimes required to be non-rotationally symmetrical - e.g. generate an elliptical radiation field, which is particularly important in satellite radio in order to illuminate asymmetrical regions on earth. In such cases, measures must be taken when designing a directional antenna to influence the shape of its radiation field.

Zu diesem Zweck ist bei einer aus der DE-A 30 07 150 bekannten Richtantenne, damit diese ein elliptisches Strahlungsfeld erzeugt, der Erreger mit Einschlitzungen und einem an seiner Innenwandung angebrachten dielektrischen Rohr versehen, das über die Erregeröffnung hinausragt und die Einschlitzungen abdeckt. Ebenfalls zur Erzeugung eines elliptischen Strahlungsfeldes ist bei einer aus der DE-A- 29 39 562 hervorgehenden Antenne ein Hornstrahler mit einer elliptischen Apertur eingesetzt. Hornstrahler mit elliptischer Apertur bringen aber gewisse fertigungstechnische Probleme mit sich.For this purpose, in a directional antenna known from DE-A 30 07 150, so that it generates an elliptical radiation field, the exciter is provided with slots and a dielectric tube attached to its inner wall, which projects beyond the exciter opening and covers the slots. Also to generate an elliptical radiation field is a horn with an antenna resulting from DE-A-29 39 562 an elliptical aperture. Horn emitters with an elliptical aperture, however, have certain manufacturing problems.

Aus A. W. LOVE "Reflector Antennas", Part IV:" Microwave Antennas Derived from the Cassegrain Telescope", 1978, Institute of Electrical and Electronics Engineers, US, S. 144 ist eine Richtantenne mit einem Haupt- und einem Subreflektor bekannt, bei der der Hauptreflektor vor einem Hornstrahler angeordnet ist. Der vor dem Horn befindliche Bereich des Hauptreflektors ist als ein Gitter ausgebildet, das die Funktion eines Polarisationsfilters hat. Es läßt Wellen einer bestimmten Polarisationsrichtung durch, wogegen Wellen einer dazu orthogonalen Polarisationsrichtung reflektiert werden.A directional antenna with a main and a subreflector is known from AW LOVE "Reflector Antennas", Part IV: "Microwave Antennas Derived from the Cassegrain Telescope", 1978, Institute of Electrical and Electronics Engineers, US, p. 144 Main reflector is arranged in front of a horn. The area of the main reflector located in front of the horn is designed as a grating, which has the function of a polarization filter. It transmits waves of a certain polarization direction, whereas waves of a polarization direction orthogonal to it are reflected.

Der Erfindung liegt nun die Aufgabe zugrunde, eine Richtantenne anzugeben, die fertigungstechnisch einfach herzustellende Mittel aufweist, die in der Lage sind, dem Strahlungsfeld der Antenne eine gewünschte Form zu verleihen.The invention is based on the object of specifying a directional antenna which has means which are simple to manufacture in terms of production technology and which are able to give the radiation field of the antenna a desired shape.

Erfindungsgemäß wird diese Aufgabe durch die Merkmale des Anspruchs 1 gelöst.According to the invention, this object is achieved by the features of claim 1.

Vorteilhafte Weiterbildungen der Erfindung gehen aus den Unteransprüchen hervor.Advantageous developments of the invention emerge from the subclaims.

Anhand eines in der Zeichnung dargestellten Ausführungsbeispiels wird nachfolgend die Erfindung näher erläutert.

  • Fig. 1 zeigt eine Richtantenne im Querschnitt und
  • Fig. 2 eine Sicht in Richtung auf die Apertur des Hornstrahlers der Antenne.
Based on an embodiment shown in the drawing, the invention is explained in more detail below.
  • Fig. 1 shows a directional antenna in cross section and
  • Fig. 2 is a view towards the aperture of the antenna horn.

Der Fig. 1 ist eine Richtantenne zu entnehmen, die aus einem Hauptreflektor 1, einem in dessen Fußpunkt befindlichen Hornstrahler 2 und einem Subreflektor 3 besteht, der die vom Hornstrahler 2 abgegebene Strahlung zum Hauptreflektor 1 hin umlenkt. Außerhalb des Hornstrahlers 2 ist in dessen Strahlungsfeld eine leitende Scheibe 4 angeordnet, welche eine Öffnung 5 aufweist, die mindestens so groß wie die Apertur des Hornstrahlers 2 ist. Diese Scheibe 4 beeinflußt die Form des vom Hornstrahler 2 ausgehenden Strahlungsfeldes je nachdem wie Größe und Form der Öffnung 5 in der Scheibe 4 gewählt sind und wie weit die Scheibe 4 von der Hornapertur entfernt ist. Wie die Draufsicht auf die Scheibe 4 und die dahinter liegende Apertur des Hornstrahlers 2 in Fig. 2 zeigt, ist die Öffnung 5 in der Scheibe 4 z.B. ellipsenförmig, um dem vom runden Hornstrahler ausgehenden rotationssymmetrischen Strahlungsfeld die Form einer Ellipse zu verleihen. Und zwar verkleinert sich nur der Winkel der Strahlung in der Ebene der kleinen Ellipsenachse, wogegen der Winkel der Strahlung in der Ebene der großen Ellipsenachse unbeeinflußt bleibt. Man kann also trotz des Einsatzes eines runden Hornstrahlers, der fertigungstechnisch problemlos herstellbar ist, ein asymmetrisches Strahlungsfeld erzeugen. Es sind auch andere das Strahlungsfeld formende nicht rotationssymmetrische Öffnungsquerschnitte möglich, z.B. rechteckförmige, rautenförmige etc..1 shows a directional antenna which consists of a main reflector 1, a horn antenna 2 located at the base thereof and a subreflector 3 which deflects the radiation emitted by the horn antenna 2 towards the main reflector 1. Outside the horn 2, a conductive disk 4 is arranged in its radiation field, which has an opening 5 which is at least as large as the aperture of the horn 2. This disk 4 influences the shape of the radiation field emanating from the horn radiator 2, depending on how the size and shape of the opening 5 in the disk 4 are selected and how far the disk 4 is from the horn aperture. As the top view of the pane 4 and the aperture of the horn radiator 2 behind it in FIG. 2 shows, the opening 5 in the disc 4 is, for example, elliptical in order to give the rotationally symmetrical radiation field emanating from the round horn radiator the shape of an ellipse. In fact, only the angle of the radiation in the plane of the small ellipse axis decreases, whereas the angle of the radiation in the plane of the large ellipse axis remains unaffected. So you can, despite the use of a round horn, the is easy to manufacture in terms of production technology, generate an asymmetrical radiation field. Other non-rotationally symmetrical opening cross sections forming the radiation field are also possible, for example rectangular, diamond-shaped etc.

Eine Scheibe mit einem rotationssymmetrischen (runden) Öffnungsquerschnitt vor einem kreisrunden Hornstrahler hat den vorteilhaften Effekt, daß der Flankenabfall der Primärcharakteristik außerhalb des Durchlaßwinkelbereichs der Scheibe sehr steil wird. Das bedeutet, daß die unerwünschte Subreflektorüberstrahlung überproportional stark gedämpft wird. Da die Strahlwinkelreduktion frequenzabhängig ist, kann die natürliche Frequenzabhängigkeit der Keulenbreite des Hornes kompensiert werden und der Reflektor so frequenzabhängig ausgeleuchtet werden.A disc with a rotationally symmetrical (round) opening cross section in front of a circular horn has the advantageous effect that the slope of the flank of the primary characteristic becomes very steep outside the transmission angle range of the disc. This means that the unwanted subreflector radiation is disproportionately damped. Since the beam angle reduction is frequency-dependent, the natural frequency dependency of the lobe width of the horn can be compensated and the reflector can thus be illuminated as a function of frequency.

Statt nur eine leitende Scheibe 4 mit einer Öffnung 5 zu verwenden, wie es aus der Zeichnung hervorgeht, können ebenso zwei oder noch mehr leitende Scheiben parallel hintereinander angeordnet werden, deren gegenseitige Abstände und Öffnungsquerschnitte so zu wählen sind, daß die gewollte Beeinflussung des Strahlungsfeldes erreicht wird.Instead of using only one conductive disc 4 with an opening 5, as can be seen from the drawing, two or more conductive discs can also be arranged in parallel, the mutual spacings and opening cross sections of which must be selected such that the desired influence on the radiation field is achieved becomes.

Es ist zweckmäßig, die leitende Scheibe 4 so gekrümmt auszubilden (vgl. Fig. 1), daß evtl. daran reflektierte Strahlen nicht konzentriert auf dem Hauptreflektor 1 fallen, sondern in weitem Winkel gestreut werden. Durch Beschichten der leitenden Scheibe 4 mit einem Absorbermaterial lassen sich störende Strahlreflexionen verringern.It is expedient to design the conductive disc 4 so curved (see FIG. 1) that any rays reflected thereon do not fall concentrated on the main reflector 1, but are scattered at a wide angle. By coating the conductive disc 4 with an absorber material, disturbing beam reflections can be reduced.

Als Befestigungsmittel für die Scheibe 4 sind Haltestreben 6 vorgesehen, die einerseits am Rand des Hornstrahlers 2 angebracht und andererseits mit der Scheibe 4 verbunden sind.Holding struts 6 are provided as fastening means for the pane 4, which are attached to the edge of the horn 2 and are connected to the pane 4.

Claims (7)

  1. Directional antenna, which consists of a main reflector (1), a horn radiator (2) disposed in the base thereof and a subsidiary reflector (3) which deflects the radiation, which is issued by the horn radiator (2), to the main reflector (1), characterised thereby that arranged outside the horn radiator (2) in the radiation field thereof and in front of the subsidiary reflector (3) is at least one conductive disc (4), which has an opening (5) which is at least as large as the horn aperture, and that the spacing of the disc (4) from the horn aperture and the opening cross-section (5) are so dimensioned that the radiation field receives a desired shape.
  2. Directional antenna according to claim 1, characterised thereby that the opening (5) in the conductive disc (4) is circular.
  3. Directional antenna according to claim 1, characterised thereby that the opening (5) in the conductive disc (4) is rectangular.
  4. Directional antenna according to claim 1, characterised thereby that the opening (5) in the conductive disc (4) is elliptical.
  5. Directional antenna according to claims 1 and 4, characterised thereby that the horn radiator (2) has a round cross-section and the opening (5) in the conductive disc (4) has an elliptical crosssection.
  6. Directional antenna according to one of the preceding claims, characterised thereby that the conductive disc (4) is coated with an absorbent material.
  7. Directional antenna according to one of the preceding claims, characterised thereby that the conductive disc (4) is so curved that the rays reflected thereat are widely scattered.
EP88106532A 1987-05-14 1988-04-23 Directional antenna Expired - Lifetime EP0290844B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19873716033 DE3716033A1 (en) 1987-05-14 1987-05-14 DIRECTIONAL ANTENNA
DE3716033 1987-05-14

Publications (3)

Publication Number Publication Date
EP0290844A2 EP0290844A2 (en) 1988-11-17
EP0290844A3 EP0290844A3 (en) 1990-12-19
EP0290844B1 true EP0290844B1 (en) 1993-07-21

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Application Number Title Priority Date Filing Date
EP88106532A Expired - Lifetime EP0290844B1 (en) 1987-05-14 1988-04-23 Directional antenna

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DE (2) DE3716033A1 (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20100015599A (en) * 2007-03-16 2010-02-12 모바일 에스에이티 리미티드 A vehicle mounted antenna and methods for transmitting and/or receiving signals

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1048298B (en) * 1957-03-20 1959-01-08 Deutsche Bundespost Antenna arrangement with a parabolic mirror fed in via a hollow pipe
DE1516821B2 (en) * 1966-04-22 1974-01-31 Siemens Ag, 1000 Berlin U. 8000 Muenchen Waveguide radiator with a rotationally symmetrical sector-shaped radiation diagram
DE2607809A1 (en) * 1976-02-26 1977-09-01 Deutsche Bundespost Low bunching microwave aerial - has transverse slot width and spacing from aperture chosen to ensure phase side lobes reversal
DE2842298A1 (en) * 1978-09-28 1980-05-22 Siemens Ag Directional antenna for very short waves - has secondary reflector formed by central metal part on dielectric cover of main reflector
DE2939562C2 (en) * 1979-09-29 1982-09-09 Licentia Patent-Verwaltungs-Gmbh, 6000 Frankfurt Horn antenna as exciter for a reflector antenna with a hybrid mode excitation part
DE3007150A1 (en) * 1980-02-26 1981-09-03 Siemens AG, 1000 Berlin und 8000 München MICROWAVE DIRECTIONAL ANTENNA FOR PRODUCING A SECTOR-SHAPED RADIATION
US4578681A (en) * 1983-06-21 1986-03-25 Chaparral Communications, Inc. Method and apparatus for optimizing feedhorn performance

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
A.W. Love "Reflector Antennas", Part IV:"Microwave Antennas Derived from the Cassegrain Telescope" and Part VI:"The Radiaton Pattern and Impedance of Offset and Symmetrical Near-FieldCassegrainian and Gregorian Antennas, 1978,Institute and Electrical and Electronics Engineers US, Pages 136,144,219,220. *
H.Jasik et al."Antenna Engineering Handbook", Second Edition, chapter 17:"Reflector Antennas", 1984,McGraw-Hill, New York, Pages 17-28 to 17-29. *

Also Published As

Publication number Publication date
DE3882428D1 (en) 1993-08-26
EP0290844A3 (en) 1990-12-19
DE3716033A1 (en) 1988-12-01
EP0290844A2 (en) 1988-11-17

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