Patent US3995275A successfully refreshed from Google Patents.
US3995275A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reflector antenna having main and subreflector of diverse curvature
Assignee: Mitsubishi Electric Corp
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Filing: 1974-06-25
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Granted: 1976-11-30
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Expires: 1994-06-25
Abstract
Abstract A reflector antenna used for radar, etc, has a subreflector so as to give a relatively large aperture diameter for a primary radiator, and to decrease the effect of the outer atmosphere. A subreflector having a different curvature in a vertical plane than a curvature in a horizontal plane is provided whereby an antenna having a different beam width in the vertical plane to that in the horizontal plane is provided even though a primary radiator having a rotationally symmetrical beam is employed.
Inventors
- 👤 Shinichi Betsudan
- 👤 Masanao Iimori
- 👤 Motoo Mizusawa
- 👤 Shuji Urasaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 10:31
CPC Classifications
H; H01; H01Q; H01Q19/00; H01Q19/10; H01Q19/18; H01Q19/19
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
83 words
A reflector antenna which comprises: a primary radiator for generating a rotationally symmetrical beam; a main reflector having a composite curved surface formed by a central sectional curve determined by the shape of a beam in a vertical plane and a parabola transverse to the curve, said central and parabolic surfaces having spaced focal points; a subreflector having a composite curved surface formed by a central sectional two dimensional curve and a group of two dimensional curves transverse to the central sectional curve;
Claim 2
Dependent Claim
83 words
A reflector antenna which comprises: a primary radiator for generating a rotationally symmetrical beam; a main reflector having a composite curved surface formed by a central sectional curve determined by the shape of a beam in a vertical plane and a parabola transverse to the curve, said central and parabolic surfaces having spaced focal points; a subreflector having a composite curved surface formed by a central sectional two dimensional curve and a group of two dimensional curves transverse to the central sectional curve;
Claim 3
Dependent Claim
38 words
wherein the subreflector has a hyperbolic curve having focuse corresponding to a phase center of the primary radiator and to the focus of the parabola transverse to the central sectional curve of the surface of the main reflector.
Claim 4
Dependent Claim
38 words
wherein the subreflector has a hyperbolic curve having focuse corresponding to a phase center of the primary radiator and to the focus of the parabola transverse to the central sectional curve of the surface of the main reflector.
Claim 5
Dependent Claim
14 words
A reflector antenna which comprises: a primary radiator for generating a rotationally symmetrical beam;
Claim 6
Dependent Claim
14 words
A reflector antenna which comprises: a primary radiator for generating a rotationally symmetrical beam;
Claim 7
Dependent Claim
147 words
a main reflector having a different aperture diameter in the vertical plane to that of the horizontal plane; and a subreflector having a curved surface to convert a spherical wave to a wave having a different curvature in the vertical plane to that of the horizontal plane to permit the beam to be effectively intercepted by the main reflector; wherein the main reflector has parabolic curves having a different focus in the vertical plane to that of the horizontal plane, the subreflector has hyperbolic curves having focuses corresponding to a phase center of the primary radiator and to the focus of a vertical parabolic curve of the main reflector in the vertical plane, and the subreflector has hyperbolic curves having focuses corresponding to a phase center of the primary radiator and to the focus of a horizontal parabolic curve of the main reflector in the horizontal plane.
Claim 8
Dependent Claim
147 words
a main reflector having a different aperture diameter in the vertical plane to that of the horizontal plane; and a subreflector having a curved surface to convert a spherical wave to a wave having a different curvature in the vertical plane to that of the horizontal plane to permit the beam to be effectively intercepted by the main reflector; wherein the main reflector has parabolic curves having a different focus in the vertical plane to that of the horizontal plane, the subreflector has hyperbolic curves having focuses corresponding to a phase center of the primary radiator and to the focus of a vertical parabolic curve of the main reflector in the vertical plane, and the subreflector has hyperbolic curves having focuses corresponding to a phase center of the primary radiator and to the focus of a horizontal parabolic curve of the main reflector in the horizontal plane.
References Cited (Backward Citations)
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US3518686A
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US3448456A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-11-30 | 1980-05-31 | 1980-11-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-11-30 | 1984-05-31 | 1984-11-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-11-30 | 1988-05-31 | 1988-11-30 | $7700.00 | Window Closed / Lapsed |