US3803623A - Microstrip antenna - Google Patents
Microstrip antenna Download PDFInfo
- Publication number
- US3803623A US3803623A US00296592A US29659272A US3803623A US 3803623 A US3803623 A US 3803623A US 00296592 A US00296592 A US 00296592A US 29659272 A US29659272 A US 29659272A US 3803623 A US3803623 A US 3803623A
- Authority
- US
- United States
- Prior art keywords
- radiator
- elements
- antenna according
- impedance
- transmission line
- 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
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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
-
- 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
- MICROSTRIP ANTENNA [75] Inventor: Lincoln H; Chariot, Jr., Tampa, Fla.
- ABSTRACT Microstrip antenna having a single radiator element or an array of radiator elements.
- the radiator elements are elliptical with the minor axis in the E plane being approximately M2 V ,u e
- the radiator elements and feed elements are contained in a broad surface which is uniformly spaced from a ground element by a dielectric layer, and are impedance matched to a transmission line by selecting a feedpoint on the periphery of the radiator element at which the input impedance of the radiator element effects an impedance match to the transmission line.
- Microstrip is a term which is commonly applied to non-radiating circuit element such as microwave filters, couplers, tuning stubs and other elements comprising flat conductive strips which are spaced from a single continuous ground plane element by a dielectric layer.
- Microstrip elements are generally known to be poor radiators of electromagnetic energy.
- the theoretical studies concerning elliptical microstrip elements repprted by Irish in Electronics Letters Apr. 8th 1971, Vol. 7, No. 7, page 149; and by Kretzschmar in IEEE Transactions on Microwave Theory and Techniques, May, 1972, page 342 indicate that although such an element would resonate efficiently at a wavelength for which either ellipse axis approximates A/(Z VEIE 'or in a number of other modes, the Q factor of such element would be on the order of 1,000 or higher, thereby preeluding efficient radiation.
- microstrip element into an efficient radiator of electromagnetic radiation.
- the feed element be coupled to the microstrip element at the correct position.
- the microstrip element provides an antenna of high aperture efficiency and useful bandwidth which is readily massproducible at low cost.
- An antenna according to the present invention which is constructed to be impedance matched to a transmission line of an input impedance Z at a wavelength )r for radiating or detecting electromagnetic radiation signals having the wavlength A, includes a thin conductive radiator element having a broad surface and two unequal orthogonal axes of symmetry in the broad surface for defining E and H planes, which planes respectively include said axes;
- a conductive ground element uniformly spaced from and more than coextensive with the radiator element for defining a radiator aperture
- a single electrical feed element is coupled to the radiator element at an off-axis feedpoint on the latter selected for impedance matching the radiator and feed elements to the transmission line.
- the axis which is within the E plane should be approximately A/(2 WE). A broader bandwidth is provided when the minor axis is in the E plane.
- the input impedance of the radiator element is dependent upon the position of thefeedpoint on the periphery of the radiator element.
- This input impedance is approximately zero at the axis which lies in the H plane and increases along the periphery, becoming maximum at the axis which lies in the E plane.
- the feedpoint-input impedance relationship is symmetrical in the quadrants on either side of the E plane and in the quadrants on either side of the H plane, except that the relative phase of the radiated signal reverses by as the feedpoint crosses the H plane.
- This feature makes it relatively easy to impedance match the radiator element and the electrical feed element to the transmission line, since one need only select a feedpoint on the radiator element periphery which provides the desired input impedance at the wavelength of the electromagnetic radiation to be radiated or received. Also, except when the radiator element is a circle, the orientation of the plane of polarization is relatively independent of the position of the feedpoint.
- the embodiment of the antenna wherein the radiator element is circular has certain unique properties. Because the polarization plane of the circular radiator element antenna is dependent upon the combination of the feedpoint and the transmission line characteristics, and not dependent upon the physical placement of major and minor axes, the polarization plane can be predetermined by merely adjusting the electrical characteristics of the impedance match to the transmission line. Thus the plane of polarization can be varied for scanning or searching functions by electronically varying the reactive characteristics of the impedance match to the transmission line.
- the preferred shape of the radiator element is that of an ellipse, although rectangles or other orthogonally symmetrical configurations may also be used. I found that the best combination of high aperture efficiency and, useful bandwidth are realized with an ellipse having an eccentricity of about 0.65. The upper practical limit of eccentricity appears to be about 0.9.
- an excellent impedance match can thus be made .to transmission lines having an input impedance in a range of from to 150 ohms.
- the unloaded Q factor as measured with a network analyzer was observed to be less than 75, and the loaded Q factor less than 25.
- the unloaded Q factor was observed to be less than 25, and the loaded Q factor less than l2, thereby resulting in a usable half-power bandwidth of about 2%.
- a gain of about 6 db was measured for a single element antenna, and a gain of about 1 1 db was measured for a four element array antenna. The radiation efficiency was determined to be greater than 95% of theoretical efficiency.
- the spacing of the radiator element from the ground element is not a function of the wavelength of the electromagnetic radiation.
- extremely low profile antennas may be provided, wherein the thickness of the dielectric layer for uniformly spacing the radiator element from the ground element is extremely thin.
- a thickness in a range between about A/(2O W775?) and AK 50 m.) is preferred. Within this range a greater bandwidth is obtained with thicker substrates.
- radiator and feed elements are easily achieved by etching the radiator and feed elements from one side of high quality double clad circuit boards of the desired design thickness.
- an array of radiator elements is appropriately distributed on a broad surface of the circuit board.
- the impedances and lengths of the feed elements which interconnect the array of radiator elements to the transmission line and by suitably selecting the quadrants and locations of the raidator element feedpoints, power may be distributed to a plurality of radiator elements in accordance with the desired illumination function, wherein the side lobes may be controlled.
- the radiator elements may be properly phased and individually impedance matched to the feed elements and to the transmission line.
- the radiated or received radiation beam is a pencil beam which is highly directional in both the E and H planes.
- Linear arrays may also be constructed to produce fan beams which are highly directional in a plane which includes a line joining the radiator elements, which plane may be either and E or an H plane depending upon the orientation of the elliptical radiator elements.
- the individual radiator elements are themselves directional the fields in the plane of the array near the radiator elements are low, thereby allowing the transmission line and the connector element lines to be routed close to the radiator elements. Also when adjacent radiator elements are placed close together, the usual problems of mutual field coupling are not as great.
- FIG. 1 is a perspective view of an antenna according to the present invention, having a single radiator element.
- FIG. 2 shows approximate values of input impedance of an elliptical radiator element at various feedpoints on the periphery thereof.
- FIG. 3 is a graph showing the value of the resistance component of the input impedanceof the radiator element of FIG. 2, as a function of the height of the feedpoint from the H axis.
- FIG. 4 is a graph of a measured radiation pattern for the antenna of FIG. 1.
- FIG. 5 is a plan view of a multiple element array antenna according to the present invention.
- FIG. 6 is a graph of measured gain and radiation patterns for the antenna of FIG. 5.
- FIG. 7 is a schematic representation of a system employing an antenna having a circular radiator element for scanning or search applications.
- FIG. 1 A single radiator element embodiment of the antenna of the present invention is shown in FIG. 1, wherein the thicknesses of the copper clad radiator, ground and feed elements are exaggerated.
- the antenna 10 includes a dielectric layer 12, which uniformly separates a ground element 14 from a radiator element 16 and an electrical feed element 18.
- the radiator element 16 is an ellipse having an eccentricity of 0.65.
- the feed element 18 is illustrated as being directly connected to the radiator element 16, at a feedpoint 22 but it may be capacitively coupled thereto. Also the feed elements 18 may be connected to a transmission line by quarter wave transformers or other impedance transitions.
- the antenna is made from a double copper clad low-loss printed circuit board material by etching one layer to form the radiator element 16 and the feed element 18.
- the feedpoint 22 was selected to match a transmission line characteristic impedance of 50 ohms to a radiator element input impedance of 50 ohms.
- the impedance of the feed element 18, as determined by its width, is also 50 ohms.
- the dielectric layer 12 is polytetrafluoroethylene (PTFE), which has a relative dielectric constant e, of about 2.5, and a relative permeability t, of 1.0.
- PTFE polytetrafluoroethylene
- copper layers are about 35 micrometers thick, and the dielectric layer has a thickness of about 1.5 millimeters.
- FIG. 2 shows approximate values of radiator element input impedance, in ohms, at various feedpoints on the periphery on the elliptical radiator element, as empirically determined for the embodiment described above, when designed to radiate at approximately 2.6 GI-Iz, with the E field parallel to the minor axis.
- FIG. 3 is a graph showing the value of the resistance component of the radiator element input impedance in ohms as a function of the height of the feedpoint from the H axis in terms of wavelength A.
- FIG. 3 is applicable for only the above described embodiment.
- the gain for this antenna 10 was measured at +5.95 db over isotropic. This measurement was made by using the commonly used two antenna technique. This measured gain is about 95% of the theoretical gain.
- the gain and radiation pattern for the antenna 10, as designed in accordance with the teaching of the present invention for radiating a 2.6 GHz signal, is shown in FIG. 4. Measurements were made in the E plane.
- a multiple element array antenna 24 is shown in FIG. 5.
- the antenna 24 is made from the same materials as used in the single element antenna 10 described above.
- the antenna 24 has four radiator elements 26 which are individually coupled to interconnected feed elements 28 and 29.
- the feed elements 28 and 29 branch out from a trunk feed element 30 which is connected to the transmission line.
- the trunk feed element 30 is tapered so as to change its impedance from 50 ohms at the terminal 32 for connection to the transmission line, to ohms at the junction 34' where it divides to form the branch elements 36.
- the branch feed elements 36 are each tapered so as to change their respective impedances from 50 ohms at the junction 34 to 35 ohms at the junction 38 where it divides to form the feed elements 28 and 29.
- the feed elements 28 and 29 are each 70 ohms, and the feedpoints 42 on the radiator elements 26 are selected to match a radiator element input impedance of 70 ohms.
- the feedpoints may be at any of four different points on the periphery of the radiator elements 26 for any given selected input impedance.
- the 180 phase difference which exists for feedpoints on either side of the major ellipse axis enables groupings of two or four radiator elements 26 to be fed from a single trunk feed element with the difference in the lengths between the lines 28 and 29 being only )t/2 rather than a full wavelength A.
- an estimated loss of approximately 0.5 db was saved by using this technique.
- FIG. 5 is drawn to scale.
- the E planes 46 and 48 are separated by 0.55 A and H planes 52 and 54 are separated by 0.42 A.
- the gain for the four element array antenna 24 was found to be about ll db, which is approximately equal to the theoretical gain, as based on the antenna aperture corresponding to the area of the ground plane.
- the gain and radiation patterns 56 and 58, respectively measured in the E and H planes, are shown in the polar graph of FIG. 6.
- the frequency of the radiated signal was 2.57 GHz.
- the voltage standing wave ratio (VSWR) was observed to be 1.5 to l.
- a 26 db gain array involves the use of the same design techniques described above.
- the major problems are related to the physical size of the array and the need to control phase and power distribution across the array.
- the array will generate pencil beams or flat fan beams both of which will often require binomial or other power distribution to eliminate high side lobes.
- planar array of elliptical radiator elements accurate control of this power distribution is readily achievable because of the design flexibility in choosing the feed points, phase and load impedance. Approximately 128 elements are required for a 26 db gain uniformly illuminated square array 9 X 9 wavelengths in size.
- This figure of 128 is an estimate based on the 11 db achieved for the 4 element array and further based on the assumption that an additional 3 db is obtained each time the array is doubled in size and that near theoretical efficiency is not sacrificed by the additional line loss, mismatch loss and phasing error. For arrays this size, the greatest design difficulty will be in eliminating phase errors and in reducing sidelobe content, especially for designs in monopulse applications.
- FIG. 7 shows an embodiment wherein an antenna 60 has a circular radiator element 62 connected to a transmission line 64 by a feed element 66.
- the transmission line 64 is connected to a radio frequency signal source 68.
- Variable reactance elements such as varactors and 72, are respectively connected between the transmission line 64 and an electrical ground, and between the radiator element 62 and ground.
- Both varactors 70,72 are connected to a variable D.C. source 74.
- D.C. source 74 By varying the D.C. voltage to the varactors 70,72 the plane of polarization of the antenna 60 is likewise var-' ied, thereby enablingthe antenna to be used for scanning or search applications.
- a microstrip antenna which is impedance matched to a transmission line of an impedance'Z at a wavelength It for radiating or detecting electromagnetic radiation signals having the wavelength A, comprising a thin conductive radiator element having a broad surface and two unequal orthogonal axes of symmetry in the broad surface for defining E and H planes which planes respectively include said axes,
- a conductive ground element uniformly spaced from and more than coextensive with the radiator element for defining a radiator aperture
- a single electrical-feed element for connection to the transmission line and coupled to a peripheral portion of the radiator element at a feedpoint which is of said axes.
- radiator element is an ellipse having an eccentricity greater than zero.
- a microstrip antenna which is impedance matched to a transmission line of an impedance Z at a wavelength A for radiating or detecting electromagnetic radiation signals having the wavelength A, comprising a thin circular conductive radiator element having a broad surface and a diameter of approximately A/(Z Mr);
- a conductive ground element uniformly spaced from and more than coextensive with the radiator element for defining a radiator aperture
- an electrical feed element for connection to the transmission line and coupled to the radiator element at a feedpoint selected for impedance matching the radiator and feed elements to the transmission line;
- variable reactance elements coupled to the radiator element and the transmission line for enabling a plane of polarization of the antenna to be varied by varying the reactance of the variable reactance elements.
- a microstrip antenna which is impedance matched to a transmission line of an impedance Z at a wavelength A for radiating or detecting electromagnetic radiation signals having the wavelength A, comprising an array of thin conductive radiator elements distributed on a broad surface, said radiator elements individually having two unequal orthogonal axes of symmetry in the broad surface for defining E and H planes which planes respectively include said axes with the axis within the E plane being approximately A/( 2 W a conductive ground element uniformly spaced from and more than coextensive with the radiator elemerits for defining a radiator aperture;
- each radiator element has a single said feed element, at least some of which are coupled to the radiator elements at feedpoints off of said axes.
- a microstrip antenna which is impedance matched to a transmission line of an impedance Z at a wavelength )t for radiating or detecting electromagnetic radiation signals having the wavelength A, comprising an array of thin circular conductive radiator elements distributed on a borad surface, said radiator elements individually having a diameter in the broad surface of approximately )t/(Z VETQ);
- a conductive ground element uniformly spaced from and more than coextensive with the radiator elements for defining a radiator aperture
- variable reactance elements coupled to the radiator elements and the transmission line for enabling a plane of polarization of the antenna to be varied by varying the reactance of the variable reactance elements.
- An antenna according to claim 1 wherein the position of the feedpoint on the radiator element is selected so that the impedance of the radiator element at the feedpoint is equal to the impedance of the feed eleselected so that the impedance of each radiator element at said feedpoint. ment at its feedpoint is equal to the impedance of the 24.
Priority Applications (8)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US00296592A US3803623A (en) | 1972-10-11 | 1972-10-11 | Microstrip antenna |
NL7313467A NL7313467A (it) | 1972-10-11 | 1973-10-01 | |
JP48113776A JPS4974464A (it) | 1972-10-11 | 1973-10-09 | |
AU61246/73A AU6124673A (en) | 1972-10-11 | 1973-10-10 | Microstrip antenna |
IT53044/73A IT994388B (it) | 1972-10-11 | 1973-10-10 | Perfezionamento nelle antenne per microonde |
DE19732351440 DE2351440A1 (de) | 1972-10-11 | 1973-10-10 | Mikrostreifenantenne |
GB4740273A GB1389397A (en) | 1972-10-11 | 1973-10-10 | Microstrip antenna |
FR7336247A FR2203182B1 (it) | 1972-10-11 | 1973-10-10 |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US00296592A US3803623A (en) | 1972-10-11 | 1972-10-11 | Microstrip antenna |
Publications (1)
Publication Number | Publication Date |
---|---|
US3803623A true US3803623A (en) | 1974-04-09 |
Family
ID=23142693
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US00296592A Expired - Lifetime US3803623A (en) | 1972-10-11 | 1972-10-11 | Microstrip antenna |
Country Status (8)
Country | Link |
---|---|
US (1) | US3803623A (it) |
JP (1) | JPS4974464A (it) |
AU (1) | AU6124673A (it) |
DE (1) | DE2351440A1 (it) |
FR (1) | FR2203182B1 (it) |
GB (1) | GB1389397A (it) |
IT (1) | IT994388B (it) |
NL (1) | NL7313467A (it) |
Cited By (29)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3921177A (en) * | 1973-04-17 | 1975-11-18 | Ball Brothers Res Corp | Microstrip antenna structures and arrays |
US3971125A (en) * | 1975-03-03 | 1976-07-27 | Raytheon Company | Method of making an antenna array using printed circuit techniques |
US3972049A (en) * | 1975-04-24 | 1976-07-27 | The United States Of America As Represented By The Secretary Of The Navy | Asymmetrically fed electric microstrip dipole antenna |
US3978488A (en) * | 1975-04-24 | 1976-08-31 | The United States Of America As Represented By The Secretary Of The Navy | Offset fed electric microstrip dipole antenna |
DE2638539A1 (de) * | 1975-08-25 | 1977-03-10 | Ball Brothers Res Corp | Doppelfrequenz-mikrostreifenantenne |
US4012741A (en) * | 1975-10-07 | 1977-03-15 | Ball Corporation | Microstrip antenna structure |
US4051478A (en) * | 1976-11-10 | 1977-09-27 | The United States Of America As Represented By The Secretary Of The Navy | Notched/diagonally fed electric microstrip antenna |
US4063246A (en) * | 1976-06-01 | 1977-12-13 | Transco Products, Inc. | Coplanar stripline antenna |
US4063245A (en) * | 1975-02-17 | 1977-12-13 | The Secretary Of State For Defence In Her Britannic Majesty's Government Of The United Kingdom Of Great Britain And Northern Ireland | Microstrip antenna arrays |
US4069483A (en) * | 1976-11-10 | 1978-01-17 | The United States Of America As Represented By The Secretary Of The Navy | Coupled fed magnetic microstrip dipole antenna |
US4070676A (en) * | 1975-10-06 | 1978-01-24 | Ball Corporation | Multiple resonance radio frequency microstrip antenna structure |
US4089003A (en) * | 1977-02-07 | 1978-05-09 | Motorola, Inc. | Multifrequency microstrip antenna |
US4123758A (en) * | 1976-02-27 | 1978-10-31 | Sumitomo Electric Industries, Ltd. | Disc antenna |
US4125839A (en) * | 1976-11-10 | 1978-11-14 | The United States Of America As Represented By The Secretary Of The Navy | Dual diagonally fed electric microstrip dipole antennas |
US4180817A (en) * | 1976-05-04 | 1979-12-25 | Ball Corporation | Serially connected microstrip antenna array |
US4241352A (en) * | 1976-09-15 | 1980-12-23 | Ball Brothers Research Corporation | Feed network scanning antenna employing rotating directional coupler |
US4320402A (en) * | 1980-07-07 | 1982-03-16 | General Dynamics Corp./Electronics Division | Multiple ring microstrip antenna |
EP0154858A2 (de) * | 1984-03-15 | 1985-09-18 | BROWN, BOVERI & CIE Aktiengesellschaft | Antenne |
US4914445A (en) * | 1988-12-23 | 1990-04-03 | Shoemaker Kevin O | Microstrip antennas and multiple radiator array antennas |
US4937585A (en) * | 1987-09-09 | 1990-06-26 | Phasar Corporation | Microwave circuit module, such as an antenna, and method of making same |
US5165109A (en) * | 1989-01-19 | 1992-11-17 | Trimble Navigation | Microwave communication antenna |
US5307556A (en) * | 1991-07-04 | 1994-05-03 | Harada Kogyo Kabushiki Kaisha | Method of manufacturing a micro-strip antenna |
US5323168A (en) * | 1992-07-13 | 1994-06-21 | Matsushita Electric Works, Ltd. | Dual frequency antenna |
US5444452A (en) * | 1992-07-13 | 1995-08-22 | Matsushita Electric Works, Ltd. | Dual frequency antenna |
US20060055489A1 (en) * | 2000-02-24 | 2006-03-16 | Hisatake Okamura | Dual mode band-pass filter |
US20060220828A1 (en) * | 2005-04-04 | 2006-10-05 | Xlink Enterprises, Inc. | Autonomous interrogating transponder for direct communications with other transponders |
US20080224740A1 (en) * | 2007-03-16 | 2008-09-18 | The Regents Of The University Of California | Frequency mixer having ferromagnetic film |
US9082307B2 (en) | 2013-02-19 | 2015-07-14 | King Fahd University Of Petroleum And Minerals | Circular antenna array for vehicular direction finding |
US11502422B2 (en) | 2020-08-27 | 2022-11-15 | Raytheon Company | Conformal RF antenna array and integrated out-of-band EME rejection filter |
Families Citing this family (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2921856C2 (de) * | 1979-05-30 | 1985-09-12 | Siemens AG, 1000 Berlin und 8000 München | Richtantenne aus zwei eine strahlende Doppelleitung bildenden Streifenleitern und Gruppenantenne unter Verwendung mehrerer derartiger Richtantennen |
FR2492540A1 (fr) * | 1980-10-17 | 1982-04-23 | Schlumberger Prospection | Dispositif pour diagraphie electromagnetique dans les forages |
JPS5791003A (en) * | 1980-11-27 | 1982-06-07 | Nippon Telegr & Teleph Corp <Ntt> | Circular polarized wave microstrip antenna |
FR2505098A1 (fr) * | 1981-04-29 | 1982-11-05 | Modern Radio Sarl | Capteur d'ondes |
GB9702242D0 (en) * | 1997-02-04 | 1997-03-26 | Plessey Semiconductors Ltd | Alarm sensor and antenna arrangement |
WO2023127913A1 (ja) * | 2021-12-28 | 2023-07-06 | Tdk株式会社 | アンテナ、及び表示装置 |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR1050583A (it) * | 1954-01-08 | |||
US3478362A (en) * | 1968-12-31 | 1969-11-11 | Massachusetts Inst Technology | Plate antenna with polarization adjustment |
US3665480A (en) * | 1969-01-23 | 1972-05-23 | Raytheon Co | Annular slot antenna with stripline feed |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3016536A (en) * | 1958-05-14 | 1962-01-09 | Eugene G Fubini | Capacitively coupled collinear stripline antenna array |
US3611399A (en) * | 1969-11-07 | 1971-10-05 | Itt | Tilted element and tilted screen antenna |
-
1972
- 1972-10-11 US US00296592A patent/US3803623A/en not_active Expired - Lifetime
-
1973
- 1973-10-01 NL NL7313467A patent/NL7313467A/xx unknown
- 1973-10-09 JP JP48113776A patent/JPS4974464A/ja active Pending
- 1973-10-10 DE DE19732351440 patent/DE2351440A1/de active Pending
- 1973-10-10 AU AU61246/73A patent/AU6124673A/en not_active Expired
- 1973-10-10 IT IT53044/73A patent/IT994388B/it active
- 1973-10-10 FR FR7336247A patent/FR2203182B1/fr not_active Expired
- 1973-10-10 GB GB4740273A patent/GB1389397A/en not_active Expired
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR1050583A (it) * | 1954-01-08 | |||
US3478362A (en) * | 1968-12-31 | 1969-11-11 | Massachusetts Inst Technology | Plate antenna with polarization adjustment |
US3665480A (en) * | 1969-01-23 | 1972-05-23 | Raytheon Co | Annular slot antenna with stripline feed |
Cited By (44)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3921177A (en) * | 1973-04-17 | 1975-11-18 | Ball Brothers Res Corp | Microstrip antenna structures and arrays |
USRE29911E (en) * | 1973-04-17 | 1979-02-13 | Ball Corporation | Microstrip antenna structures and arrays |
US4063245A (en) * | 1975-02-17 | 1977-12-13 | The Secretary Of State For Defence In Her Britannic Majesty's Government Of The United Kingdom Of Great Britain And Northern Ireland | Microstrip antenna arrays |
US3971125A (en) * | 1975-03-03 | 1976-07-27 | Raytheon Company | Method of making an antenna array using printed circuit techniques |
US3972049A (en) * | 1975-04-24 | 1976-07-27 | The United States Of America As Represented By The Secretary Of The Navy | Asymmetrically fed electric microstrip dipole antenna |
US3978488A (en) * | 1975-04-24 | 1976-08-31 | The United States Of America As Represented By The Secretary Of The Navy | Offset fed electric microstrip dipole antenna |
DE2638539A1 (de) * | 1975-08-25 | 1977-03-10 | Ball Brothers Res Corp | Doppelfrequenz-mikrostreifenantenne |
US4070676A (en) * | 1975-10-06 | 1978-01-24 | Ball Corporation | Multiple resonance radio frequency microstrip antenna structure |
US4012741A (en) * | 1975-10-07 | 1977-03-15 | Ball Corporation | Microstrip antenna structure |
US4123758A (en) * | 1976-02-27 | 1978-10-31 | Sumitomo Electric Industries, Ltd. | Disc antenna |
US4180817A (en) * | 1976-05-04 | 1979-12-25 | Ball Corporation | Serially connected microstrip antenna array |
US4063246A (en) * | 1976-06-01 | 1977-12-13 | Transco Products, Inc. | Coplanar stripline antenna |
US4241352A (en) * | 1976-09-15 | 1980-12-23 | Ball Brothers Research Corporation | Feed network scanning antenna employing rotating directional coupler |
US4125839A (en) * | 1976-11-10 | 1978-11-14 | The United States Of America As Represented By The Secretary Of The Navy | Dual diagonally fed electric microstrip dipole antennas |
US4125837A (en) * | 1976-11-10 | 1978-11-14 | The United States Of America As Represented By The Secretary Of The Navy | Dual notch fed electric microstrip dipole antennas |
US4125838A (en) * | 1976-11-10 | 1978-11-14 | The United States Of America As Represented By The Secretary Of The Navy | Dual asymmetrically fed electric microstrip dipole antennas |
US4051478A (en) * | 1976-11-10 | 1977-09-27 | The United States Of America As Represented By The Secretary Of The Navy | Notched/diagonally fed electric microstrip antenna |
US4069483A (en) * | 1976-11-10 | 1978-01-17 | The United States Of America As Represented By The Secretary Of The Navy | Coupled fed magnetic microstrip dipole antenna |
US4089003A (en) * | 1977-02-07 | 1978-05-09 | Motorola, Inc. | Multifrequency microstrip antenna |
US4320402A (en) * | 1980-07-07 | 1982-03-16 | General Dynamics Corp./Electronics Division | Multiple ring microstrip antenna |
EP0154858A2 (de) * | 1984-03-15 | 1985-09-18 | BROWN, BOVERI & CIE Aktiengesellschaft | Antenne |
EP0154858A3 (de) * | 1984-03-15 | 1988-03-16 | BROWN, BOVERI & CIE Aktiengesellschaft | Antenne |
US4937585A (en) * | 1987-09-09 | 1990-06-26 | Phasar Corporation | Microwave circuit module, such as an antenna, and method of making same |
US4914445A (en) * | 1988-12-23 | 1990-04-03 | Shoemaker Kevin O | Microstrip antennas and multiple radiator array antennas |
US5165109A (en) * | 1989-01-19 | 1992-11-17 | Trimble Navigation | Microwave communication antenna |
US5307556A (en) * | 1991-07-04 | 1994-05-03 | Harada Kogyo Kabushiki Kaisha | Method of manufacturing a micro-strip antenna |
US5323168A (en) * | 1992-07-13 | 1994-06-21 | Matsushita Electric Works, Ltd. | Dual frequency antenna |
US5444452A (en) * | 1992-07-13 | 1995-08-22 | Matsushita Electric Works, Ltd. | Dual frequency antenna |
US7239221B2 (en) * | 2000-02-24 | 2007-07-03 | Murata Manufacturing Co., Ltd. | Dual mode band-pass filter |
US20060055489A1 (en) * | 2000-02-24 | 2006-03-16 | Hisatake Okamura | Dual mode band-pass filter |
US20060061437A1 (en) * | 2000-02-24 | 2006-03-23 | Hisatake Okamura | Dual mode band-pass filter |
US20060061436A1 (en) * | 2000-02-24 | 2006-03-23 | Hisatake Okamura | Dual mode band-pass filter |
US20060066420A1 (en) * | 2000-02-24 | 2006-03-30 | Hisatake Okamura | Dual mode band-pass filter |
US7098760B2 (en) * | 2000-02-24 | 2006-08-29 | Murata Manufacturing Co., Ltd. | Dual mode band-pass filter |
US7268648B2 (en) * | 2000-02-24 | 2007-09-11 | Murata Manufacturing Co., Ltd. | Dual mode band-pass filter |
WO2006107609A2 (en) | 2005-04-04 | 2006-10-12 | Xlink Enterprises, Inc. | Autonomous interrogating transponder for direct communications with other transponders |
US20060220828A1 (en) * | 2005-04-04 | 2006-10-05 | Xlink Enterprises, Inc. | Autonomous interrogating transponder for direct communications with other transponders |
US7432802B2 (en) | 2005-04-04 | 2008-10-07 | Xlink Enterprises, Inc. | Autonomous interrogating transponder for direct communications with other transponders |
US20080297352A1 (en) * | 2005-04-04 | 2008-12-04 | Xlink Enterprises, Inc. | Autonomous interrogating transponder for direct communications with other transponders |
US8102242B2 (en) | 2005-04-04 | 2012-01-24 | Xlink Enterprises, Inc. | Autonomous interrogating transponder for direct communications with other transponders |
US20080224740A1 (en) * | 2007-03-16 | 2008-09-18 | The Regents Of The University Of California | Frequency mixer having ferromagnetic film |
US9300251B2 (en) * | 2007-03-16 | 2016-03-29 | The Regents Of The University Of California | Frequency mixer having ferromagnetic film |
US9082307B2 (en) | 2013-02-19 | 2015-07-14 | King Fahd University Of Petroleum And Minerals | Circular antenna array for vehicular direction finding |
US11502422B2 (en) | 2020-08-27 | 2022-11-15 | Raytheon Company | Conformal RF antenna array and integrated out-of-band EME rejection filter |
Also Published As
Publication number | Publication date |
---|---|
DE2351440A1 (de) | 1974-04-25 |
GB1389397A (en) | 1975-04-03 |
NL7313467A (it) | 1974-04-16 |
IT994388B (it) | 1975-10-20 |
JPS4974464A (it) | 1974-07-18 |
FR2203182B1 (it) | 1976-10-01 |
FR2203182A1 (it) | 1974-05-10 |
AU6124673A (en) | 1975-04-10 |
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