US2835890A - Directional antenna - Google Patents
Directional antenna Download PDFInfo
- Publication number
- US2835890A US2835890A US250645A US25064551A US2835890A US 2835890 A US2835890 A US 2835890A US 250645 A US250645 A US 250645A US 25064551 A US25064551 A US 25064551A US 2835890 A US2835890 A US 2835890A
- Authority
- US
- United States
- Prior art keywords
- antenna
- slats
- scanning
- directional antenna
- radiator
- 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
Links
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q15/00—Devices for reflection, refraction, diffraction or polarisation of waves radiated from an antenna, e.g. quasi-optical devices
- H01Q15/14—Reflecting surfaces; Equivalent structures
- H01Q15/22—Reflecting surfaces; Equivalent structures functioning also as polarisation filter
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q3/00—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system
- H01Q3/12—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system using mechanical relative movement between primary active elements and secondary devices of antennas or antenna systems
Definitions
- This invention relates to antennas and, more particularly, to a high-frequency directional antenna of the scanning type such as used in radar systems.
- the antennas of the prior art which have highly directional characteristics and are capable of scanning, generally utilize a reflecting element and a small radiator, both of which are rotated or reciprocated in an arc as a unit.
- This type of antenna has many desirable characteristics but has an objectionable mass in those applicatiens wherein the antenna must scan through a selected arc with great rapidity.
- the windage and inertia of the reflector result in the necessity for very heavy mechanisms to drive the device and, in addition, demands considerable driving energy.
- the objects of this invention are obtained by the utilization of a plurality of metallic slats arranged in the configuration of a spherical zone.
- the slats are parallel to each other and are disposed at an angle of 45 degrees to the great circle at the equator of the spherical zone.
- the radiator is supported at the geometric center of the spherical zone and is inclined at an angle of 45 degrees in the same direction as the reilecting slats which it faces.
- the spherical zone shape is preferred particularly if scanning in vertical planes is to be a function.
- the reflector will be operative as long as it is a complete cage having reflecting elements at approximately 45. In fact, if scanning is to occur only in the horizontal plane, a cylindrical cage is practical.
- the slats are denoted by the numeral 9, and by the use of a plurality of such slats, the spherical zone, denoted by the numeral 10, is generated.
- the slats terminate in an upper supporting ring 11 and a lower supporting ring 12.
- the antenna 13 is supported in the center of the re- Patented May 20, 1958 tiecting cage and is shown to be disposed at the same angle as those slats which it is facing.
- the antenna is supported on the usual transmission line or wave guide 14 by means of the usual scanning and/or nodding mechanism 15.
- a radiator horn any type of radiator such as a line source beginning at one-half the spherical zone radius from the center may be used with the only requirement being that the phase front be proper and the direction of the electric field radiated be at the same 45 degree angle as that of the slats which it faces (over the region illuminated).
- the energy radiated by the antenna will be retlected from that part of the reflector which the antenna faces.
- the energy so reilected will travel across to the opposite side of the spherical zone where the slats are no longer parallel to the electric vector of the radiation field but are now normal to it.
- the reected energy will therefore readily pass through this opposite side of the reector.
- the reector may be incorporated in the structure of a radome.
- the shape of the reflecting slats may be such that the projection of any slat on a vertical plane may be spherical, parabolic or cosecant-squared.
- the device of this invention has been constructed for X-band frequencies, having a 20-inch spherical surface and a line-source feed. This arrangement results in a beam of 8 by 8 with -13 db side lobes.
- this invention provides a directional antenna of the scanning type which has reduced many fold the inertia and windage of the moving system.
- An antenna comprising the combination of a retlector having an plurality of parallel metallic elements in the form of an annular cage having the shape of a zone of revolution and in which the said elements are inclined at 45 degrees to the axis of the cage, a rotatable scanning mechanism, and a rotatable directional radiating element operatively connected and rotatable with the scanning mechanism within the connes of said zone of revolution disposed generally parallel to the metal elements which it faces and having a plane of electrical polarization generally parallel to the metallic elements which it faces and generally normal to oppositely disposed metallic elements.
Description
DIRECTINAL ANTENNA Burt J. Bittner, Albuquerque, N. Mex., assigner, by mesue assignments, to the United States of America as represented by the United States Atomic Energy Commission Application October 10, 1951, Serial No. 250,645'
2 Claims. (Cl. 343-754) This invention relates to antennas and, more particularly, to a high-frequency directional antenna of the scanning type such as used in radar systems.
The antennas of the prior art which have highly directional characteristics and are capable of scanning, generally utilize a reflecting element and a small radiator, both of which are rotated or reciprocated in an arc as a unit. This type of antenna has many desirable characteristics but has an objectionable mass in those applicatiens wherein the antenna must scan through a selected arc with great rapidity. In such applications, the windage and inertia of the reflector result in the necessity for very heavy mechanisms to drive the device and, in addition, demands considerable driving energy.
It is an object of the present invention to provide a highly directional antenna of the scanning type in which the reflecting structure is stationary and only the radiator itself need Ibe moved to provide the scanning function.
The novel features which are characteristic of this invention are set forth in particularity in the appended claims. A preferred embodiment of the invention itself, both as to its organization and method of operation together with further objects and advantages thereof may best be understood by reference to the following description taken in connection with the accompanying drawing made a part of this specification.
The objects of this invention are obtained by the utilization of a plurality of metallic slats arranged in the configuration of a spherical zone. The slats are parallel to each other and are disposed at an angle of 45 degrees to the great circle at the equator of the spherical zone. The radiator is supported at the geometric center of the spherical zone and is inclined at an angle of 45 degrees in the same direction as the reilecting slats which it faces.
It is noted that the spherical zone shape is preferred particularly if scanning in vertical planes is to be a function. However, it is apparent that the reflector will be operative as long as it is a complete cage having reflecting elements at approximately 45. In fact, if scanning is to occur only in the horizontal plane, a cylindrical cage is practical.
Referring to the gure of the drawing, the slats are denoted by the numeral 9, and by the use of a plurality of such slats, the spherical zone, denoted by the numeral 10, is generated. The slats terminate in an upper supporting ring 11 and a lower supporting ring 12.
The antenna 13 is supported in the center of the re- Patented May 20, 1958 tiecting cage and is shown to be disposed at the same angle as those slats which it is facing. The antenna is supported on the usual transmission line or wave guide 14 by means of the usual scanning and/or nodding mechanism 15. In this connection, although a radiator horn is shown, any type of radiator such as a line source beginning at one-half the spherical zone radius from the center may be used with the only requirement being that the phase front be proper and the direction of the electric field radiated be at the same 45 degree angle as that of the slats which it faces (over the region illuminated).
The energy radiated by the antenna will be retlected from that part of the reflector which the antenna faces. The energy so reilected will travel across to the opposite side of the spherical zone where the slats are no longer parallel to the electric vector of the radiation field but are now normal to it. The reected energy will therefore readily pass through this opposite side of the reector.
It is apparent that the reector may be incorporated in the structure of a radome.
ln order to provide for desirable characteristics of directivity, the shape of the reflecting slats may be such that the projection of any slat on a vertical plane may be spherical, parabolic or cosecant-squared.
The device of this invention has been constructed for X-band frequencies, having a 20-inch spherical surface and a line-source feed. This arrangement results in a beam of 8 by 8 with -13 db side lobes.
From the foregoing description, it is seen that this invention provides a directional antenna of the scanning type which has reduced many fold the inertia and windage of the moving system.
What is claimed is:
l. An antenna comprising the combination of a retlector having an plurality of parallel metallic elements in the form of an annular cage having the shape of a zone of revolution and in which the said elements are inclined at 45 degrees to the axis of the cage, a rotatable scanning mechanism, and a rotatable directional radiating element operatively connected and rotatable with the scanning mechanism within the connes of said zone of revolution disposed generally parallel to the metal elements which it faces and having a plane of electrical polarization generally parallel to the metallic elements which it faces and generally normal to oppositely disposed metallic elements.
2. An antenna as claimed in claim l wherein the radiating element is supported by nodding means.
References Cited in the tile of this patent UNITED STATES PATENTS 1,805,591 Ohl May 19, 1931 2,223,950 Brown Dec. 3, 1940 2,510,020 Iams May 30, 1950 2,532,919 Johnson Dec. 5, 1950 2,608,656 Korman Aug. 26, 1952 2,622,199 Ramsay et al. Dec. 16, 1952 FOREIGN PATENTS 668,231 Germany Nov. 28, 1938
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US250645A US2835890A (en) | 1951-10-10 | 1951-10-10 | Directional antenna |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US250645A US2835890A (en) | 1951-10-10 | 1951-10-10 | Directional antenna |
Publications (1)
Publication Number | Publication Date |
---|---|
US2835890A true US2835890A (en) | 1958-05-20 |
Family
ID=22948583
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US250645A Expired - Lifetime US2835890A (en) | 1951-10-10 | 1951-10-10 | Directional antenna |
Country Status (1)
Country | Link |
---|---|
US (1) | US2835890A (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2989746A (en) * | 1956-08-21 | 1961-06-20 | Marconi Wireless Telegraph Co | Scanning antenna system utilizing polarization filters |
US3031664A (en) * | 1959-10-01 | 1962-04-24 | Marconi Wireless Telegraph Co | Polarisation screen and filter for radio waves |
US3169245A (en) * | 1959-05-15 | 1965-02-09 | Bell Telephone Labor Inc | Passive repeaters for satellite communication systems |
FR2429506A1 (en) * | 1978-06-22 | 1980-01-18 | Sperry Rand Corp | CIRCULAR SCANNING RADAR ANTENNA |
US20050179615A1 (en) * | 2003-11-03 | 2005-08-18 | Mrstik A. V. | Inflatable-collapsible transreflector antenna |
Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1805591A (en) * | 1926-12-18 | 1931-05-19 | American Telephone & Telegraph | Signaling system |
DE668231C (en) * | 1935-05-26 | 1938-11-28 | Julius Pintsch Kom Ges | Reflector arrangement |
US2223950A (en) * | 1938-09-16 | 1940-12-03 | Rca Corp | Polarized wave transmitting system |
US2510020A (en) * | 1947-10-28 | 1950-05-30 | Rca Corp | Reflector for radar navigation |
US2532919A (en) * | 1947-04-21 | 1950-12-05 | Johnson William Arthur | Radio aerial system, and particularly directive aerial system |
US2608656A (en) * | 1950-02-17 | 1952-08-26 | Rca Corp | Microwave antenna |
US2622199A (en) * | 1948-04-16 | 1952-12-16 | Marconi Wireless Telegraph Co | Radio aerial system |
-
1951
- 1951-10-10 US US250645A patent/US2835890A/en not_active Expired - Lifetime
Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1805591A (en) * | 1926-12-18 | 1931-05-19 | American Telephone & Telegraph | Signaling system |
DE668231C (en) * | 1935-05-26 | 1938-11-28 | Julius Pintsch Kom Ges | Reflector arrangement |
US2223950A (en) * | 1938-09-16 | 1940-12-03 | Rca Corp | Polarized wave transmitting system |
US2532919A (en) * | 1947-04-21 | 1950-12-05 | Johnson William Arthur | Radio aerial system, and particularly directive aerial system |
US2510020A (en) * | 1947-10-28 | 1950-05-30 | Rca Corp | Reflector for radar navigation |
US2622199A (en) * | 1948-04-16 | 1952-12-16 | Marconi Wireless Telegraph Co | Radio aerial system |
US2608656A (en) * | 1950-02-17 | 1952-08-26 | Rca Corp | Microwave antenna |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2989746A (en) * | 1956-08-21 | 1961-06-20 | Marconi Wireless Telegraph Co | Scanning antenna system utilizing polarization filters |
US3169245A (en) * | 1959-05-15 | 1965-02-09 | Bell Telephone Labor Inc | Passive repeaters for satellite communication systems |
US3031664A (en) * | 1959-10-01 | 1962-04-24 | Marconi Wireless Telegraph Co | Polarisation screen and filter for radio waves |
FR2429506A1 (en) * | 1978-06-22 | 1980-01-18 | Sperry Rand Corp | CIRCULAR SCANNING RADAR ANTENNA |
US20050179615A1 (en) * | 2003-11-03 | 2005-08-18 | Mrstik A. V. | Inflatable-collapsible transreflector antenna |
US7133001B2 (en) | 2003-11-03 | 2006-11-07 | Toyon Research Corporation | Inflatable-collapsible transreflector antenna |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US3413637A (en) | Multifunction antenna having selective radiation patterns | |
US3231892A (en) | Antenna feed system simultaneously operable at two frequencies utilizing polarization independent frequency selective intermediate reflector | |
US4333082A (en) | Inhomogeneous dielectric dome antenna | |
US3845483A (en) | Antenna system | |
US2430568A (en) | Antenna system | |
US3045237A (en) | Antenna system having beam control members consisting of array of spiral elements | |
US3189907A (en) | Zone plate radio transmission system | |
US3852762A (en) | Scanning lens antenna | |
US3797020A (en) | Microwave antenna structure with aperture blocking elimination | |
US3916416A (en) | 360{20 {0 Azimuth scanning antenna without rotating RF joints | |
US2408373A (en) | Antenna | |
US3176301A (en) | Plural horns at focus of parabolic reflector with shields to reduce spillover and side lobes | |
US3881178A (en) | Antenna system for radiating multiple planar beams | |
US2527222A (en) | Scanning antenna | |
US2835890A (en) | Directional antenna | |
US4574287A (en) | Fixed aperture, rotating feed, beam scanning antenna system | |
US3775773A (en) | Technique for generating planar beams from a linear doppler line source employing a circular parallel-plate waveguide | |
US3147479A (en) | Plural juxtaposed parabolic reflectors with frequency independent feeds | |
US3273144A (en) | Narrow beam antenna system | |
US3277490A (en) | Broadband conical scan feed for parabolic antennas | |
US2549143A (en) | Microwave broadcast antenna | |
US3696436A (en) | Cassegrain antenna with absorber to reduce back radiation | |
US2720589A (en) | Rapid scanning radar antenna | |
US3795003A (en) | Schwarzschild radar antenna with a unidirectional turnstile scanner | |
US3392397A (en) | Cassegrain antenna for scanning with elliptically shaped beam |