US3795004A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cassegrain radar antenna with selectable acquisition and track modes
Assignee: United States Department of the Army
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Filing: 1973-02-26
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Granted: 1974-02-26
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Expires: 1993-02-26
Abstract
Abstract A Schwarzschild Antenna cooperates with an organ pipe scanner to achieve wide angle sectoral scanning of a high gain pencil beam. A rotatable mirror switches the antenna to conical scanning whereby microwave energy communicates between a nutating horn and reflectors of the Schwarzschild Antenna. During conical scanning, the organ pipe scanner remains unenergized. The mode of operation is selectable by the operator and the system is designed for rapid switching.
Inventors
- 👤 J Meek
- 👤 C Ravilious
- 👤 W Heinard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 22:02
CPC Classifications
H; H01; H01Q; H01Q19/00; H01Q19/10; H01Q19/18; H01Q19/19; H01Q19/191; H01Q3/00; H01Q3/12; H01Q3/16; H01Q3/18; H01Q3/24; H01Q3/245
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
101 words
A Schwarzschild antenna system comprising: reflector means for reflecting microwave energy that impinges thereon; scanner means adjacent the reflector means and communicating with the reflector means for producing a wide angle unidirectional sectoral scan; horn means disposed in adjacent spaced relationship to the reflector means and communicating with the reflector means for producing a narrow angle scan; and microwave switching means mounted adjacent to the reflector means to selectively complete microwave communication between the reflector means and either the scanner means or the horn means; whereby the switching means enables rapid selection of the sectoral scan or the narrow angle scan.
Claim 2
Dependent Claim
101 words
A Schwarzschild antenna system comprising: reflector means for reflecting microwave energy that impinges thereon; scanner means adjacent the reflector means and communicating with the reflector means for producing a wide angle unidirectional sectoral scan; horn means disposed in adjacent spaced relationship to the reflector means and communicating with the reflector means for producing a narrow angle scan; and microwave switching means mounted adjacent to the reflector means to selectively complete microwave communication between the reflector means and either the scanner means or the horn means; whereby the switching means enables rapid selection of the sectoral scan or the narrow angle scan.
Claim 3
Dependent Claim
40 words
The structure of claim 1 wherein the scanner means comprises a plurality of adjacently spaced feEd horns communicating with respective waveguide pipes to form an organ pipe scanner which produces a unidirectional scan across the outlet ends of the feedhorns.
Claim 4
Dependent Claim
20 words
The structure of claim 1 wherein the horn means comprises at least a single nutating horn for conical scan tracking.
Claim 5
Dependent Claim
29 words
The subject matter of claim 1 wherein the horn means is a multi-port assembly comprising a plurality of adjacently positioned stationary horns for operating in a steady track mode.
Claim 6
Dependent Claim
46 words
The structure of claim 2 wherein the switching means comprises a movably mounted flat mirror reflector positioned in intermediate relation between the scanner means and the horn means for selectably communicating microwave energy between the reflector means and either the scanner means or the horn means.
Claim 7
Dependent Claim
16 words
The subject matter of claim 2 wherein each of the feed horns has a pyramidal shape.
Claim 8
Dependent Claim
15 words
The structure of claim 3 wherein each of the horn means has a pyramidal shape.
Claim 9
Dependent Claim
23 words
The subject matter of claim 2 and further wherein the horn means comprises at least a single nutating horn for conical scan tracking.
Claim 10
Dependent Claim
27 words
The subject matter of claim 5 wherein the mirror is longitudinally mounted to a shaft to permit selectable rapid rotation of the mirror between two angular positions.
Claim 11
Dependent Claim
32 words
The subject matter of claim 9 wherein the shaft is connected to a torquer that selectably drives the shaft between the two angular positions in response to electrical energization of the torquer.
References Cited (Backward Citations)
US3696432A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-02-25 | 1977-08-27 | 1978-02-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-25 | 1981-08-27 | 1982-02-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-25 | 1985-08-27 | 1986-02-26 | $7700.00 | Window Closed / Lapsed |