EP0434268B1 - Mikrostreifenleiterantenne - Google Patents

Mikrostreifenleiterantenne Download PDF

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Publication number
EP0434268B1
EP0434268B1 EP90313290A EP90313290A EP0434268B1 EP 0434268 B1 EP0434268 B1 EP 0434268B1 EP 90313290 A EP90313290 A EP 90313290A EP 90313290 A EP90313290 A EP 90313290A EP 0434268 B1 EP0434268 B1 EP 0434268B1
Authority
EP
European Patent Office
Prior art keywords
array
elements
feed
radiation
antenna
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
EP90313290A
Other languages
English (en)
French (fr)
Other versions
EP0434268A3 (en
EP0434268A2 (de
Inventor
Alan Christopher Smith
Roger Philip Owens
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.)
UK Secretary of State for Defence
EMI Group Electronics Ltd
Original Assignee
Thorn EMI Electronics Ltd
UK Secretary of State for Defence
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 Thorn EMI Electronics Ltd, UK Secretary of State for Defence filed Critical Thorn EMI Electronics Ltd
Publication of EP0434268A2 publication Critical patent/EP0434268A2/de
Publication of EP0434268A3 publication Critical patent/EP0434268A3/en
Application granted granted Critical
Publication of EP0434268B1 publication Critical patent/EP0434268B1/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
    • H01Q9/00—Electrically-short antennas having dimensions not more than twice the operating wavelength and consisting of conductive active radiating elements
    • H01Q9/04—Resonant antennas
    • H01Q9/0407—Substantially flat resonant element parallel to ground plane, e.g. patch antenna
    • H01Q9/0428—Substantially flat resonant element parallel to ground plane, e.g. patch antenna radiating a circular polarised wave
    • H01Q9/0435—Substantially flat resonant element parallel to ground plane, e.g. patch antenna radiating a circular polarised wave using two feed points
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q21/00—Antenna arrays or systems
    • H01Q21/0006—Particular feeding systems
    • H01Q21/0075—Stripline fed arrays
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q21/00—Antenna arrays or systems
    • H01Q21/06—Arrays of individually energised antenna units similarly polarised and spaced apart
    • H01Q21/061—Two dimensional planar arrays
    • H01Q21/065—Patch antenna array

Definitions

  • This invention relates to a microstrip antenna comprising a substantially planar rectangular array of microstrip radiation elements each of which is capable of radiating radiation circularly polarised in one sense when energised at a first feed point and radiation circularly polarised in the opposite sense when energised at a second feed point, a first signal port for the array, first feed means coupling the first port to the first feed points of at least some of the elements of the array, a second signal port for the array, and second feed means coupling the second port to the second feed points of at least some of the elements of the array.
  • a known such antenna is disclosed in GB Patent 2189080 and in Conference Proceedings Military Microwaves '86, June 1986, Brighton, England, pages 323 - 328.
  • the array is a 3 x 2 array of square conducting elements each with two opposite corners bevelled. Each element has two feed points appropriate for left-hand circular polarization (LHCP) and two feed points appropriate for right-hand circular polarization (RHCP).
  • LHCP left-hand circular polarization
  • RHCP right-hand circular polarization
  • the array in fact is made up from two 2 x 2 element sub-arrays arranged side-by-side, with the centre two elements common to both sub-arrays.
  • the first feed means couples the first port to first feed points of all the elements of one sub-array and the second feed means couples the second port to second feed points of all the elements of the other sub-array.
  • the two feed means which therefore provide the circular polarization in the one sense and in the opposite sense respectively, are arranged side by side.
  • the relative orientation of elements in the group and the mutual phasing in the feed means conforms to the requirements of the broadbanding technique now commonly known in this art as "sequential rotation". This term will be assumed to be understood by persons familiar with microstrip antenna techniques and will not, therefore, be described further in the context of the present application.
  • a plurality of such antennae may be arranged to form an antenna array.
  • microstrip antenna array suitable for use with orthogonal linear polarisations is described in US Patent No 4,464,663. It comprises a linear array of pairs of square microstrip antenna elements, each connected to two feeds so that one feed renders each element responsive to one of two orthogonal linear polarisations and the other feed renders each element responsive to the other of the two orthogonal linear polarisations. In this way, the connections between the two input/output ports and the four associated elements render each of these four elements responsive to respective orthogonal linear polarisations.
  • the element pairs are operated back-to-back by a feed and the necessary 180° phase correction is provided by the asymmetrical connection. In this way, the isolation between the two polarisation feeds is enhanced.
  • This antenna array is narrow-band and both orthogonal linear polarisations operate at the same frequency.
  • EP-A-0360692 which was published after the priority date of the present application and which forms prior art only according to Article 54(3) and (4) EPC, discloses an antenna comprising at least two radiation elements each of which is capable of radiating radiation linearly polarized in orthogonal directions when energised at first and second feed points respectively.
  • the present invention seeks to provide an improved compact and relatively low profile microstrip antenna with a simplified feed arrangement and for which a number can be readily combined to form a composite array of arbitrary shape.
  • an antenna as defined in the first paragraph is characterized in that the rectangular array is a 2 x 2 array, in that the first feed means couples the first port to the first feed points of all the elements of the 2 x 2 array, and in that the second feed means couples the second port to the second feed points of all the elements of the 2 x 2 array in such manner that it does not overlap the first feed means when the feed means are viewed in a direction normal to the plane of the array.
  • the 2 x 2 rectangular array of microstrip radiation elements may be replaced by an array of three microstrip radiation elements in a triangular disposition.
  • a microstrip antenna 2 comprises, in the embodiment shown, four radiation elements 4 arranged as a 2 x 2 array in the form of a microstrip layer on a substrate 6.
  • the substrate 6 may comprise any suitable dielectric such as RT/duroid material.
  • the elements 4 are coupled to ports 8, 10 by means of a feed network which includes a first or outer feed 12 and a further or Inner feed 14.
  • the outer feed 12 is arranged so as to provide left hand circular polarisation (LHCP) and the inner feed 14 is arranged so as to provide right hand circular polarisation(RHCP) of signals fed via the ports 8, 10.
  • the ports 8, 10 serve, respectively, as LHCP and RHCP ports.
  • the spacing of the elements 4 is, preferably, chosen to be about 85% of the signal wavelength. The advantages of this mutual spacing are that it is large enough to enable the feed networks 8, 10 to be accommodated within the area between the patches, as shown in Figure 3, and it also ensures that the mutual coupling between the patches 4 is relatively weak.
  • the spacing is not sufficiently large to allow grating lobes to appear in the antenna radiation pattern and thereby reduce the directivity of the antenna.
  • the axial ratio of the elements 4 may be optimised at the required centre frequency of radiation by suitable choice of the length of the side of the square elements 4 and the degree of chamfering at the corners of the elements.
  • Each element 4 is capable of simultaneously radiating both LHCP and RHCP radiation from independent orthogonally positioned feed points 16, 18, as shown in Figure 3.
  • a sequentially rotated feed system is also used for the outer and inner feeds 12, 14.
  • each element 4, for the four element array shown in the drawings is rotated by 90° with respect to neighbouring patches and the outer and inner feeds 12, 14 are arranged to increase in length between consecutive elements by one-quarter the wavelength of the signal to be radiated.
  • One form of feed network providing sequential rotation is shown in Figure 3, where it can be seen that the increase in feed path length between the ports and consecutive elements occurs in an anti-clockwise direction for the outer (LHCR) feed 12 and a clockwise direction for the inner (RHCP) feed 14.
  • the feeds 12, 14 are arranged in a non-overlapping relationship. This is particularly advantageous as the feeds 12, 14 can, therefore, be arranged coplanar with the elements 4 in a purely microstrip configuration, as shown schematically in Figure 1, with the elements 4 coupled to the feeds 12,14 by either direct coupling or gap coupling techniques, as is known in this art.
  • the feeds 12, 14 may be incorporated in a separate triplate layer 20, as shown schematically in Figure 2.
  • the triplate layer 20 comprises a feed layer 20a, in which the feeds 12, 14 are defined, arranged between dielectric layers 20b and 20c.
  • the feeds 12, 14 of the feed layer 20a are coupled to the elements 4 using either direct coupling, such as pins or plated through holes extending through the substrate between the triplate feed layer 20a and the elements 4, or aperture coupling through small areas in a shared ground plane 22 which have been cleared of metallisation used to form the ground plane.
  • the use of a triplate layer 20 for the feeds 12, 14 ensures that the circularly polarised radiation from the elements 4 is not adversely affected by spurious radiation from the feeds 12,14.
  • the layout of the feeds 12, 14 can also be optimised so as to be substantially independent of the layout of the elements 4, such as laterally displacing the layout of the feeds relative to the elements. This flexibility of design can be particularly advantageous when a number of antennas are configured into a larger array.
  • the layered structure of the antenna incorporating a triplate feed layer can be seen from Figure 2.
  • the ports 8,10 may comprise any suitable microwave connector, such as SMA surface mount type connectors, protruding from a ground plane 24 of the array and the elements 4 may be fed by probes coupling, by way of the means as described above, the elements to the triplate layer 20.
  • the present invention provides an antenna of low profile with considerable design flexibility. Furthermore, the antenna can be used as a common building block of simple construction that can be used to construct larger arrays of arbitrary gain and shape which may also be made substantially conformal to curved surfaces.
  • the antenna lends itself readily to mass construction using conventional manufacturing techniques, providing a consistency of performance required for many practical applications for this type of antenna.
  • the antenna need not necessarily comprise a 2x2 array of elements.
  • Three elements in a triangular disposition can also be used with appropriate modifications of the feed system to meet the requirements of sequential rotation.
  • other shapes of element may be used such as square shape elements having a diagonally cut rectangular slot or circular patches having diametrically opposed lugs or indentations.

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  • Variable-Direction Aerials And Aerial Arrays (AREA)
  • Details Of Aerials (AREA)
  • Waveguide Aerials (AREA)

Claims (7)

  1. Mikrostreifenleiterantenne (2), umfassend eine im wesentlichen ebene rechteckige Gruppe von Mikrostreifen-Strahlungselementen (4), von denen jedes in der Lage ist, bei Erregung an einem ersten Einspeisepunkt (16) zirkular in einem Sinn polarisierte Strahlung auszusenden, und bei Erregung an einem zweiten Einspeisepunkt (18) zirkular im entgegengesetzten Sinn polarisierte Strahlung auszusenden, einen ersten Signalanschluß (8) für die Gruppe, erste Einspeisemittel (12), die den ersten Anschluß (8) mit den ersten Einspeisepunkten (16) von wenigstens einigen Elementen (4) der Gruppe verbinden, ein zweiter Signalanschluß (10) für die Gruppe und zweite Einspeisemittel (14), die den zweiten Anschluß (10) mit den zweiten Einspeisepunkten (18) von wenigstens einigen Elementen (4) der Gruppe verbinden, dadurch gekennzeichnet, daß die rechteckige Gruppe eine Zwei-mal-zwei-Gruppe ist, daß die ersten Einspeisemittel (12) den ersten Anschluß (8) mit den ersten Einspeisepunkten (16) aller Elemente (4) der Zwei-mal-zwei-Gruppe verbinden, und daß die zweiten Einspeisemittel (14) den zweiten Anschluß (10) mit den zweiten Einspeisemitteln (18) aller Elemente (4) der Zwei-mal-zwei-Gruppe derart verbinden, daß sie nicht die ersten Einspeisemittel (12) überlappen, wenn die Einspeisemittel (12, 14) in Richtung senkrecht zur Ebene der Gruppe betrachtet werden.
  2. Antenne nach Anspruch 1, bei der die ersten (12) und zweiten (14) Einspeisemittel koplanar mit den Strahlungselementen (4) sind.
  3. Antenne nach Anspruch 1, bei der die ersten (12) und zweiten (14) Einspeisemittel in eine Drei-Platten-Schicht (20) einbezogen sind, die unterhalb der Strahlungselemente liegt.
  4. Antenne nach einem der vorhergehenden Ansprüche, bei der die Strahlungselemente (4) von im wesentlichen identischer Form sind und relativ zueinander so orientiert sind, daß, wenn man von Element zu Element rund um die Gruppe geht, eine wirksame Drehung um weitere 90° in der Ebene der Gruppe von jedem zum nächsten vorhanden ist, wobei die ersten Einspeisemittel (12) so sind, daß bei Beginn von einem gegebenen Strahlungselement (4) und Herumgehen von Element zu Element um die Gruppe dadurch progressive Änderungen von λ/4 in den Längen der Signalwege von dem ersten Anschluß (8) zu den aufeinanderfolgenden Elementen (4) vorgesehen werden, und bei der die zweiten Einspeisemittel so sind, daß, beginnend von einem gegebenen Strahlungselement und Herumgehen von Element zu Element um die Gruppe dadurch progressive Änderungen von λ/4 in den Längen der Signalwege von dem zweiten Anschluß (10) zu den aufeinanderfolgenden Elementen (4) vorgesehen werden, wobei λ die Wellenlänge der Strahlung ist.
  5. Antenne nach einem der vorhergehenden Ansprüche, bei der die Strahlungselemente (4) eine quadratische Form mit zwei einander gegenüberliegenden abgeschrägten Ecken haben.
  6. Antennengruppe, die eine Vielzahl von Mikrostreifenantennen gemäß einem der vorhergehenden Ansprüche aufweist.
  7. Antenne nach Anspruch 1, bei der die rechteckige Zwei-mal-zwei-Gruppe von Mikrostreifen-Strahlungselementen (4) durch eine Gruppe von drei Mikrostreifen-Strahlungselementen in dreieckiger Anordnung ersetzt ist.
EP90313290A 1989-12-19 1990-12-07 Mikrostreifenleiterantenne Expired - Lifetime EP0434268B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB8928589 1989-12-19
GB898928589A GB8928589D0 (en) 1989-12-19 1989-12-19 Microstrip antenna

Publications (3)

Publication Number Publication Date
EP0434268A2 EP0434268A2 (de) 1991-06-26
EP0434268A3 EP0434268A3 (en) 1991-08-21
EP0434268B1 true EP0434268B1 (de) 1995-02-15

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EP90313290A Expired - Lifetime EP0434268B1 (de) 1989-12-19 1990-12-07 Mikrostreifenleiterantenne

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EP (1) EP0434268B1 (de)
AT (1) ATE118655T1 (de)
DE (1) DE69016972D1 (de)
GB (1) GB8928589D0 (de)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2009097647A1 (en) * 2008-02-04 2009-08-13 Commonwealth Scientific And Industrial Research Organisation Circularly polarised array antenna
US20220123464A1 (en) * 2019-02-06 2022-04-21 Sony Group Corporation Systems and devices for mutual directive beam switch array

Families Citing this family (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE69222464T2 (de) * 1991-05-30 1998-02-26 Toshiba Kawasaki Kk Mikrostreifenantenne
SE513711C2 (sv) * 1996-01-30 2000-10-23 Ericsson Telefon Ab L M Anordning vid antennenheter
AU2567797A (en) * 1996-04-03 1997-10-29 Johan Granholm Dual polarization antenna array with very low cross polarization and low side lobes
KR20060035942A (ko) * 2004-10-21 2006-04-27 한국전자통신연구원 금속 패치를 이용한 원형편파 패치 안테나 및 이를 이용한송/수신 배열 안테나
US7420512B2 (en) 2005-08-02 2008-09-02 M/A-Com, Inc. Antenna system
CN104282997B (zh) * 2013-10-23 2017-06-16 林伟 高效的天线阵列装置
CN104283003B (zh) * 2013-10-24 2017-05-24 林伟 高效的收发天线阵列装置
CN110034398B (zh) * 2019-05-06 2024-08-02 广州安的电子科技有限公司 天线结构及防盗门
CN110190387A (zh) * 2019-05-08 2019-08-30 成都天锐星通科技有限公司 一种单馈双圆极化微带天线
JP2024505014A (ja) * 2021-01-27 2024-02-02 アナログ・ディヴァイシス・インターナショナル・アンリミテッド・カンパニー 広い走査範囲を有する円偏波アンテナ
US11831088B1 (en) * 2023-07-19 2023-11-28 The Florida International University Board Of Trustees Dual-band antenna systems

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2189080A (en) * 1986-04-02 1987-10-14 Thorn Emi Electronics Ltd Microstrip antenna

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2636780B1 (fr) * 1988-09-21 1991-02-15 Europ Agence Spatiale Antenne composite a diplexage a polarisation circulaire

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2189080A (en) * 1986-04-02 1987-10-14 Thorn Emi Electronics Ltd Microstrip antenna

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
Electronics Letters, vol. 21, no. 10, 9th May 1985, Enage/GB, pages 437-438; M.Haneishi and H.Takazawa: "Broadband circularly polarised planar array composed of a pair of dielectric resonator antennas" *

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2009097647A1 (en) * 2008-02-04 2009-08-13 Commonwealth Scientific And Industrial Research Organisation Circularly polarised array antenna
AU2009212093B2 (en) * 2008-02-04 2014-02-20 Commonwealth Scientific And Industrial Research Organisation Circularly polarised array antenna
US8830133B2 (en) 2008-02-04 2014-09-09 Commonwealth Scientific And Industrial Research Organisation Circularly polarised array antenna
US20220123464A1 (en) * 2019-02-06 2022-04-21 Sony Group Corporation Systems and devices for mutual directive beam switch array

Also Published As

Publication number Publication date
EP0434268A3 (en) 1991-08-21
GB8928589D0 (en) 1990-02-21
ATE118655T1 (de) 1995-03-15
EP0434268A2 (de) 1991-06-26
DE69016972D1 (de) 1995-03-23

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