CA2064133C - Three dimensional microstrip patch antenna - Google Patents

Three dimensional microstrip patch antenna

Info

Publication number
CA2064133C
CA2064133C CA002064133A CA2064133A CA2064133C CA 2064133 C CA2064133 C CA 2064133C CA 002064133 A CA002064133 A CA 002064133A CA 2064133 A CA2064133 A CA 2064133A CA 2064133 C CA2064133 C CA 2064133C
Authority
CA
Canada
Prior art keywords
substrate
antenna
layer
base
interior
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
CA002064133A
Other languages
French (fr)
Other versions
CA2064133A1 (en
Inventor
Walter Feller
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.)
Novatel Inc
Original Assignee
Novatel Communications Ltd
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 Novatel Communications Ltd filed Critical Novatel Communications Ltd
Publication of CA2064133A1 publication Critical patent/CA2064133A1/en
Application granted granted Critical
Publication of CA2064133C publication Critical patent/CA2064133C/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01QANTENNAS, i.e. RADIO AERIALS
    • H01Q9/00Electrically-short antennas having dimensions not more than twice the operating wavelength and consisting of conductive active radiating elements
    • H01Q9/04Resonant antennas
    • H01Q9/0407Substantially flat resonant element parallel to ground plane, e.g. patch antenna
    • H01Q9/0471Non-planar, stepped or wedge-shaped patch
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01QANTENNAS, i.e. RADIO AERIALS
    • H01Q1/00Details of, or arrangements associated with, antennas
    • H01Q1/27Adaptation for use in or on movable bodies
    • H01Q1/32Adaptation for use in or on road or rail vehicles
    • H01Q1/325Adaptation for use in or on road or rail vehicles characterised by the location of the antenna on the vehicle
    • H01Q1/3275Adaptation for use in or on road or rail vehicles characterised by the location of the antenna on the vehicle mounted on a horizontal surface of the vehicle, e.g. on roof, hood, trunk
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01QANTENNAS, i.e. RADIO AERIALS
    • H01Q9/00Electrically-short antennas having dimensions not more than twice the operating wavelength and consisting of conductive active radiating elements
    • H01Q9/04Resonant antennas
    • H01Q9/0407Substantially flat resonant element parallel to ground plane, e.g. patch antenna
    • H01Q9/0428Substantially flat resonant element parallel to ground plane, e.g. patch antenna radiating a circular polarised wave

Abstract

An antenna assembly comprises a dome-like substrate with a ground plane layer on the interior surface of the substrate and a radiative patch on the outer surface of the substrate. The cavity defined by the substrate is closed off by a base having a conductive layer that is connected to the ground plane layer, thereby to isolate the cavity and circuit elements that may be disposed therein. Preferably the substrate has a polyhedral form and the radiative patch is a polygon having apex portions that extend down over the side surface of the substrate to enhance the sensitivity of the antenna at low elevations.

Description

A THREE DIMENSIONAL MICROSTRIP PATCH ~.~NNA

FIELD OF THE lNv~ IoN
This invention relates generally to antennas and more specifically to a microstrip antenna assembly that includes both an antenna and signal conditioning circuitry that processes signals received by the antenna.

BACRGROUND OF THE lNV~ ION

A conventional microstrip antenna is generally planar and comprises an antenna element in the form of a conductive layer on one side of a dielectric substrate layer, and a conductive ground layer on the opposite side of the substrate.
Antennas of this type are advantageous in a number of applications because of their relatively low profile and ease of manufacture, as well as their compatibility with other components implemented in microstrip configurations.
In prior microstrip antennas, the propagation pattern may be substantially independent of azimuth at high elevation angles, that is, for radiation directions that do not depart greatly from the normal. At low elevations, on the other hand, the sensitivity of the same antenna may be largely dependent on azimuthal direction and, in some cases, the antenna is insensitive in all such directions at low elevations. An example of this characteristic is a circularly polarized microstrip antenna which, in prior convention configurations, has reasonable sensitivity with the desired polarization only at elevations that are relatively close to the normal.
However, for a number of applications, the antenna must function effectively over a wide range of elevation angles and, in particular, it is necessary that the antenna function at relatively low angles. An example of such an application is an antenna used with a Global Positioning System receiver. The receiver will ordinarily receive circularly polarized signals simultaneously from a number of earth-orbiting satellites having a wide range of instantaneous elevations.
Receiving antennas usually function in conjunction with signal conditioning circuit components such as phase shifters, filters, and amplifiers that may also be arranged in microstrip configurations. The present invention relates in part to an assembly of a microstrip antenna and these auxiliary circuit components in a compact form to facilitate the use of the assembly in small transportable equipment. An example of such equipment is a receiver for receiving and processing signals transmitted by the satellites in the Global Positioning System.
It is therefore an object of this invention to provide a microstrip antenna that is sensitive to circularly polarized signals over a wide range of elevation angles.
Another object is to provide an antenna assembly that has - a relatively low cost and provides adequate shielding of auxiliary components from the environment.
An antenna assembly embodying the invention comprises a microstrip antenna having a dome-like configuration and a substrate, carrying the signal conditioning components associated with the antenna, attached to and closing off the interior of the dome structure. A radiative patch extends over and down from the top surface of the substrate. The signal conditioning components, which are thus disposed within the interior of the dome structure, are interconnected by micro-strip conductors. The ground plane for this microstrip 206~133 circuitry is connected to a metallic lining on the interior surface of the dome structure which serves as the "ground plane" for the antenna. These two ground planes thus effectively completely enclose the signal conditioning circuitry and thereby effectively shield it from the exterior of the assembly.
The dome structure preferably has a polyhedral con-figuration, specifically a truncated pyramid, with side surfaces facing in various azimuthal directions. The radia-tive patch is preferably rectangular, with corner portionsextending down over the side surfaces. These corner portions are, in effect, circularly polarized sub-antennas having substantial sensitivity at low elevations. Consequently, the overall antenna exhibits good sensitivity to circularly polarized signals over a wide range of elevations and in all azimuthal directions.
This arrangement provides for a compact, easily manu-factured assembly. Moreover, the assembly is rugged and the components thereof are protected from electromagnetic inter-ference and environmental stress, which makes the assemblyhighly useful for a number of applications including the Global Positioning System receivers mentioned above.
Thus, to summarize, the present invention provides according to one aspect an antenna assembly comprising:
A. a dome-like substrate having a surface with a top portion and side portions extending from said top portion, said side -3a- 2061133 surface portions defining an opening opposite said top surface portion;
B. a ground plane layer on the interior surface of said substrate;
C. a radiative layer on the exterior surface of said substrate, said radiative layer having a central portion on said top surface portion and apex portions extending from said top surface portion and down over the side surface portions; and D. a base contacting said substrate and closing said opening, said base having a first surface facing the interior of said substrate and a second surface opposite said first surface.
According to another aspect, the invention provides an antenna comprising:
A. a domelike polyhedral substrate having top and side surfaces;
B. a groundplane layer on the interior surface of said substrate, and C. an antenna element on the exterior surface of said substrate, said antenna element being a polygonal patch having a central portion on said top surface and apex portions extend-ing from said central portion down over side surfaces of said substrate.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. lA is an isometric view of an antenna assembly embodying the invention, comprising an antenna assembled with a printed circuit board base;

,~

,~

-3b-206~133 Fig. lB is a side view of the antenna assembly of Fig. lA;
Fig. lC is a top view of the antenna assembly of Fig.
lA;
Fig. lD iS a bottom view of the antenna used in the assembly;
Fig. 2A is a top view of the printed circuit board base of the antenna assembly of Fig. lA;
Fig. 2B is an edge view of the base; and Fig. 3 is an isometric view of an alternative embodiment of the invention;
DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS
As shown in Figs. lA-lC, an antenna assembly incorpora-ting the invention comprises an antenna element in the form of a conductive layer 12, disposed on a dome-shaped dielectric sub-strate 13. The substrate 13 preferably has a polyhedral configuration, specifically a truncated pyramid having a top surface 14 and sloping side surfaces 15-18.
Fig. lD shows the interior of the substrate 13. The inner surface of the substrate is covered with a metallic layer " I -that serves as a ground "plane" for the antenna and also as a shield for components housed in the interior of the dome as described below. The layer 25 extends beneath the lower edge of the substrate.
Returning to Figs. lA-lC, the antenna element 12 comprises a central portion 12a that, in the illustrative embodiment, covers the substrate top surface 14. The element 12 also includes wing portions 12b-12e that extend down along the side surfaces lS-18. As best seen in Fig. lC, the layer 12 is an essentially square patch whose corners have, in effect, been folded down on the substrate side surfaces 15-18. The dimensions of the square are such as would be used for a conventional planar patch antenna that is fed at the midpoints of two of its edges for circular polarization. Thus, as also shown in Figs. lA-lC, feed conductors 27 and 29 extend from the junctures of wing portions 12d and 12e, and 12e and 12b, respectively, to the lower edge of substrate surface 18 and then under the edge to gaps in the ground plane layer 25 (Fig.
lD). They thus contact conductive pads 31 and 33 on the top surface of a base 23 (Fig. 2A).
As shown in Fig. 2, the base 23 has a microstrip configuration. The bottom surface (Fig. 2B) is covered with a groundplane conductor 35. The top surface is covered with a conductive layer 36 except in those areas containing signal and power conductors. This layer is in contact with the ground plane layer 25 of the substrate 13. The conductive layers 35 and 36 are connected together by a layer 37 (Fig. 2B) that extends around the edges of the base 23.
The pads 31 and 33 are connected to a phase shifter 38 in the form of a square hybrid which combines the signals from the pads and applies the resultant signal to a conductor 40. Each of the legs 42 has an electrical length of one-quarter wavelength. Thus the electrical distances from the pads 31 and 33 to the conductor 40 differ by one-quarter wavelength and the phase shifter thereby provides a 90 relative phase shift to the signals received from the antenna conductor 12 (Fig. lA) by way of the pads 31 and 33. The phase shifter also includes a resistive termination 44 at the remaining corner of the hybrid to prevent undesirable reflections from that corner.
With this arrangement, the antenna exhibits sensitivity to circularly polarized signals over a wide range of elevations and, in particular, at materially lower elevations than planar patch antennas. Moreover, the entire assembly is compact and of low cost, and it provides effective shielding of the components contained therein from the environment.
With further reference to Fig. 2A, the conductor 40 connects to a narrow-band filter 46 mounted on the base 23.
The output of the filter 46 is applied to a conductor 48, which feeds the filtered signal from the antenna to an amplifier indicated at 50. The output of the amplifier 50 is coupled through a capacitor 52 to a connector 54 extending through the base 23. The connector, in turn, delivers the RF signal to the demodulation and signal processing elements (not shown) of a receiver incorporating the antenna assembly.
The connector 54 also provides power for the amplifier 50, the DC path to the amplifier including a resistor 56 in parallel with the capacitor 52.
Fig. 3 depicts another variation of the invention. In this case the polyhedral dome 70 is a truncated tetrahedron. The antenna layer 72 is essentially a triangular patch that covers the top surface of the dome, with the apices of the patch extending down over the side surfaces. In all other respects, the antenna assembly of Fig. 3 is like that of Figs. 1 and 2.
Thus the antenna layer 72 connects to feeders (not shown) that provide circular polarization.

The foregoing description has been limited to specific embodiments of this invention. It will be apparent, however, that variations and modifications may be made to the invention, with the attainment of some or all of its advantages.

206~133 Therefore, it is the object of the appended claims to cover all such variations and modifications as come within the true spirit and scope of the invention.

Claims (11)

1. An antenna assembly comprising:
A. a dome-like substrate having a surface with a top portion and side portions extending from said top portion, said side surface portions defining an opening opposite said top surface portion;
B. a ground plane layer on the interior surface of said substrate;
C. a radiative layer on the exterior surface of said substrate, said radiative layer having a central portion on said top surface portion and apex portions extending from said top surface portion and down over the side surface portions; and D. a base contacting said substrate and closing said opening, said base having a first surface facing the interior of said substrate and a second surface opposite said first surface.
2. The assembly defined in claim 1 in which said base includes a conductive layer on said second surface and means electrically connecting said conductive layer to said ground plane layer, thereby to electrically isolate the volume bounded by said substrate and said base.
3. The assembly of claim 2 including:
A. feed means comprising a conductor disposed on said substrate and connected to said radiative layer for conducting signals to or from said radiative layer, B. circuit means including conductors disposed on said first surface of said base and connected to said feed means for processing signals received by said antenna assembly.
4. The assembly defined in claim 2 including:
A. feed means including first and second conductors disposed on said substrate and connected to said radiative layer, B. conductors in the form of a hybrid disposed on said first surface of said base, and C. signal conditioning components disposed within said interior of said substrate and connected to operate on signals received by said radiative layer and passed through said hybrid, D. means connecting said hybrid to said first and second conductors to provide a circular polarization characteristic for said antenna assembly.
5. An antenna comprising:
A. a domelike polyhedral substrate having top and side surfaces, B. a groundplane layer on the interior surface of said substrate, and C. an antenna element on the exterior surface of said substrate, said antenna element being a polygonal patch having a central portion on said top surface and apex portions extend-ing from said central portion down over side surfaces of said substrate.
6. The antenna of claim 5 in which:
A. said substrate is a truncated pyramid having a rectangular top surface and B. said patch is rectangular.
7. The antenna of claim 5 in which:
A. said substrate is a truncated tetrahedron having a triangular top surface and B. said patch is triangular.
8. The antenna of claim 5 further comprising a base con-tacting said substrate and closing the interior thereof, said base having a first surface facing the interior of said substrate and a second surface opposite said first surface.
9. The antenna of claim 8 including a conductive layer on said second surface and means electrically connecting said conductive layer to said ground plane layer, thereby to electrically isolate the volume bounded by said substrate and said base.
10. The antenna defined in claim 9 including:
A. feed means including first and second conductors disposed on said substrate and connected to said radiative layer, B. conductors in the form of a hybrid disposed on said first surface of said base, and C. signal conditioning components disposed within said interior of said substrate and connected to operate on signals received by said radiative layer and passed through said hybrid, D. means connecting said hybrid to said first and second conductors to provide a circular polarization characteristic for said antenna.
11. The antenna assembly defined in claim 3 further including means connected to said feed means to provide a circular polarization characteristic for said radiative layer.
CA002064133A 1991-05-03 1992-03-26 Three dimensional microstrip patch antenna Expired - Lifetime CA2064133C (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US07/695,279 US5200756A (en) 1991-05-03 1991-05-03 Three dimensional microstrip patch antenna
US07/695,279 1991-05-03

Publications (2)

Publication Number Publication Date
CA2064133A1 CA2064133A1 (en) 1992-11-04
CA2064133C true CA2064133C (en) 1996-03-26

Family

ID=24792376

Family Applications (1)

Application Number Title Priority Date Filing Date
CA002064133A Expired - Lifetime CA2064133C (en) 1991-05-03 1992-03-26 Three dimensional microstrip patch antenna

Country Status (2)

Country Link
US (1) US5200756A (en)
CA (1) CA2064133C (en)

Families Citing this family (49)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5467095A (en) * 1992-06-19 1995-11-14 Rodal; Eric B. Low profile antenna
US5442366A (en) * 1993-07-13 1995-08-15 Ball Corporation Raised patch antenna
JP3185513B2 (en) * 1994-02-07 2001-07-11 株式会社村田製作所 Surface mount antenna and method of mounting the same
JPH07249925A (en) * 1994-03-10 1995-09-26 Murata Mfg Co Ltd Antenna and antenna system
US5969680A (en) * 1994-10-11 1999-10-19 Murata Manufacturing Co., Ltd. Antenna device having a radiating portion provided between a wiring substrate and a case
EP0806810A3 (en) * 1996-05-07 1998-04-08 Ascom Tech Ag Antenna formed of a strip-like resonance element over a base plate
US5995062A (en) * 1998-02-19 1999-11-30 Harris Corporation Phased array antenna
US5995044A (en) * 1998-05-01 1999-11-30 Novatel, Inc. Method and apparatus for characterizing multipath interference in circularly polarized signals
US6236367B1 (en) * 1998-09-25 2001-05-22 Deltec Telesystems International Limited Dual polarised patch-radiating element
US6150993A (en) * 1999-03-25 2000-11-21 Zenith Electronics Corporation Adaptive indoor antenna system
AU5984099A (en) 1999-09-20 2001-04-24 Fractus, S.A. Multilevel antennae
BR9917541A (en) * 1999-10-26 2002-08-13 Fractus Sa Arrangement of elements in an antenna with different frequency bands
US6366250B1 (en) 1999-12-09 2002-04-02 Sirf Technology, Inc. Wrist mounted wireless instrument and antenna apparatus
EP2051325A1 (en) 2000-01-19 2009-04-22 Fractus, S.A. Fractal and space-filling transmission lines, resonators, filters and passive network elements
ATE302473T1 (en) 2000-01-19 2005-09-15 Fractus Sa ROOM-FILLING MINIATURE ANTENNA
DE60037142T2 (en) * 2000-04-19 2008-09-18 Advanced Automotive Antennas, S.L. ADVANCED MULTI-RANGE ANTENNA FOR MOTOR VEHICLES
ES1046677Y (en) * 2000-06-27 2001-11-16 Martinez Martin Gabriel ENERGY REGENERATING DEVICE APPLICABLE ON AUDIO AND VIDEO SUPPORTS, AS WELL AS IN PLAYERS.
US7511675B2 (en) * 2000-10-26 2009-03-31 Advanced Automotive Antennas, S.L. Antenna system for a motor vehicle
EP1358696A1 (en) 2001-02-07 2003-11-05 Fractus, S.A. Miniature broadband ring-like microstrip patch antenna
ATE364238T1 (en) * 2001-04-16 2007-06-15 Fractus Sa DOUBLE BAND DUAL POLARIZED GROUP ANTENNA
JP2002374122A (en) 2001-06-15 2002-12-26 Murata Mfg Co Ltd Circularly polarized antenna and radio apparatus using the same
AU2002327367A1 (en) * 2001-07-26 2003-02-17 Chad Edward Bouton Electromagnetic sensors for biological tissue applications
EP1436857B1 (en) * 2001-10-16 2008-01-23 Fractus, S.A. Multifrequency microstrip patch antenna with parasitic coupled elements
US9755314B2 (en) 2001-10-16 2017-09-05 Fractus S.A. Loaded antenna
ATE364911T1 (en) * 2001-10-16 2007-07-15 Fractus Sa LOADED ANTENNA
EP1942551A1 (en) 2001-10-16 2008-07-09 Fractus, S.A. Multiband antenna
ES2190749B1 (en) 2001-11-30 2004-06-16 Fractus, S.A "CHAFF" MULTINIVEL AND / OR "SPACE-FILLING" DISPERSORS, AGAINST RADAR.
US7275427B1 (en) 2002-03-06 2007-10-02 Michelin Recherche Et Technique S.A. Device for mounting electronic monitoring components to a tire
US6888510B2 (en) * 2002-08-19 2005-05-03 Skycross, Inc. Compact, low profile, circular polarization cubic antenna
JP2004318466A (en) * 2003-04-16 2004-11-11 Matsushita Electric Ind Co Ltd Gift coupon, gift coupon issuing system, and system for using gift coupon
US7429952B2 (en) * 2005-12-23 2008-09-30 Hemisphere Gps Inc. Broadband aperture coupled GNSS microstrip patch antenna
US8738103B2 (en) 2006-07-18 2014-05-27 Fractus, S.A. Multiple-body-configuration multimedia and smartphone multifunction wireless devices
US7924233B2 (en) * 2006-12-22 2011-04-12 Wistron Neweb Corporation Three-dimensional antenna and related wireless communication device
TWI352451B (en) * 2006-12-22 2011-11-11 Wistron Neweb Corp Three-dimensional wideband antenna and related wir
CN101217214B (en) * 2007-01-05 2011-09-21 启碁科技股份有限公司 A stereo wide frequency aerial and corresponding wireless communication device
DE102007004612B4 (en) * 2007-01-30 2013-04-11 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. Antenna device for transmitting and receiving electromagnetic signals
US7436363B1 (en) 2007-09-28 2008-10-14 Aeroantenna Technology, Inc. Stacked microstrip patches
US8085203B1 (en) 2008-04-18 2011-12-27 Aero Antenna Inc. Ground surrounded non-resonant slot-like patch antenna
US7928924B1 (en) 2008-05-28 2011-04-19 United States Of America As Represented By Secretary Of The Navy Variable position antenna shield
DE102009048229B4 (en) * 2009-10-05 2021-01-21 Sennheiser Electronic Gmbh & Co. Kg Antenna unit for wireless audio transmission
GB2474117B (en) * 2009-10-05 2013-01-09 Sennheiser Electronic Antenna unit for wireless audio transmission
US9306262B2 (en) * 2010-06-01 2016-04-05 Raytheon Company Stacked bowtie radiator with integrated balun
US8745853B2 (en) * 2010-07-05 2014-06-10 Universal Display Corporation Antenna fabrication with three-dimensional contoured substrates
WO2013064204A1 (en) * 2011-11-04 2013-05-10 Kathrein-Werke Kg Patch radiator
US9748656B2 (en) * 2013-12-13 2017-08-29 Harris Corporation Broadband patch antenna and associated methods
CN104409842A (en) * 2014-11-27 2015-03-11 广州中海达卫星导航技术股份有限公司 Single-layer broadband GNSS (Global Navigation Satellite System) measurement antenna
GB2538726A (en) * 2015-05-26 2016-11-30 Harada Ind Co Ltd Antenna
DE102018201575B3 (en) * 2018-02-01 2019-06-13 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. antenna device
KR102533667B1 (en) 2018-08-24 2023-05-17 삼성전자주식회사 Antenna assembly comprising antennas formed on inclined side surface of printed circuit board and electronic device comprising the same

Family Cites Families (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3346865A (en) * 1964-12-10 1967-10-10 Jr Howard S Jones Slot antenna built into a dielectric radome
US3921177A (en) * 1973-04-17 1975-11-18 Ball Brothers Res Corp Microstrip antenna structures and arrays
US4117489A (en) * 1975-04-24 1978-09-26 The United States Of America As Represented By The Secretary Of The Navy Corner fed electric microstrip dipole antenna
US4326203A (en) * 1975-04-24 1982-04-20 The United States Of America As Represented By The Secretary Of The Navy Corner fed electric non rectangular microstrip dipole antennas
US4067016A (en) * 1976-11-10 1978-01-03 The United States Of America As Represented By The Secretary Of The Navy Dual notched/diagonally fed electric microstrip dipole antennas
US4101895A (en) * 1977-02-14 1978-07-18 The United States Of America As Represented By The Secretary Of The Army Multifrequency antenna system integrated into a radome
US4162499A (en) * 1977-10-26 1979-07-24 The United States Of America As Represented By The Secretary Of The Army Flush-mounted piggyback microstrip antenna
US4736454A (en) * 1983-09-15 1988-04-05 Ball Corporation Integrated oscillator and microstrip antenna system
JPS62216409A (en) * 1986-03-17 1987-09-24 Aisin Seiki Co Ltd Antenna unit
JP2572622B2 (en) * 1987-07-10 1997-01-16 大日本印刷株式会社 Device for creating original sheets for scanners
DE3738513A1 (en) * 1987-11-13 1989-06-01 Dornier System Gmbh MICROSTRIP LADDER AERIAL
JPH0659009B2 (en) * 1988-03-10 1994-08-03 株式会社豊田中央研究所 Mobile antenna
US4992799A (en) * 1989-09-28 1991-02-12 Motorola, Inc. Adaptable antenna

Also Published As

Publication number Publication date
CA2064133A1 (en) 1992-11-04
US5200756A (en) 1993-04-06

Similar Documents

Publication Publication Date Title
CA2064133C (en) Three dimensional microstrip patch antenna
US5917458A (en) Frequency selective surface integrated antenna system
EP0872912B1 (en) Circular-polarization antenna
US4916457A (en) Printed-circuit crossed-slot antenna
US5212494A (en) Compact multi-polarized broadband antenna
US4431998A (en) Circularly polarized hemispheric coverage flush antenna
Garg Microstrip antenna design handbook
US6847328B1 (en) Compact antenna element and array, and a method of operating same
US6218997B1 (en) Antenna for a plurality of radio services
US6218991B1 (en) Compact planar inverted F antenna
US5952971A (en) Polarimetric dual band radiating element for synthetic aperture radar
EP0716774B1 (en) A folded dipole antenna
US5990849A (en) Compact spiral antenna
JPH06152227A (en) Microstrip antenna and its constituent part
US5353035A (en) Microstrip radiator for circular polarization free of welds and floating potentials
GB2172148A (en) Antenna
US5270722A (en) Patch-type microwave antenna
US4081803A (en) Multioctave turnstile antenna for direction finding and polarization determination
US6211839B1 (en) Polarized planar log periodic antenna
US6486847B1 (en) Monopole antenna
US5126751A (en) Flush mount antenna
US5323168A (en) Dual frequency antenna
US7170449B2 (en) Antenna system for georadar
US5945950A (en) Stacked microstrip antenna for wireless communication
WO1996035241A1 (en) Antenna unit

Legal Events

Date Code Title Description
EEER Examination request
MKEX Expiry