US4121220A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flat radar antenna employing circular array of slotted waveguides
Assignee: Thales SA
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Filing: 1977-02-02
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Granted: 1978-10-17
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Expires: 1997-02-02
Abstract
Abstract A flat radar antenna comprises a generally circular array of juxtaposed radiators constituted by slotted waveguides, the array being divided into four quadrants each composed of a multiplicity of groups of radiators. The radiator groups of the entire array are connected to a high-frequency transceiver via parallel paths of identical electrical length, consituted in one embodiment by cascaded couplers of magic-T type, whereby the bandwidth of the antenna equals that of each group so as to facilitate frequency scanning.
Inventors
- 👤 Antoine Scillieri
- 👤 Alain Caillaud
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 11:06
CPC Classifications
H; H01; H01Q; H01Q21/00; H01Q21/0006; H01Q21/0037; H01Q21/0043; H01Q21/005; H01Q3/00; H01Q3/22
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
83 words
In a radar system including a transmit/receive unit of high-frequency waves, the combination therewith of an antenna comprising a planar array of juxtaposed radiators in the form of mutually parallel slotted waveguides, said array being divided into four quadrants each composed of a multiplicity of substantially square radiator groups, and feed means forming paths of identical electrical lengths extending from said unit to all the radiator groups of each quadrant, the radiator groups of each quadrant being arrayed symmetrically about a quadrantal bisector.
Claim 2
Dependent Claim
83 words
In a radar system including a transmit/receive unit of high-frequency waves, the combination therewith of an antenna comprising a planar array of juxtaposed radiators in the form of mutually parallel slotted waveguides, said array being divided into four quadrants each composed of a multiplicity of substantially square radiator groups, and feed means forming paths of identical electrical lengths extending from said unit to all the radiator groups of each quadrant, the radiator groups of each quadrant being arrayed symmetrically about a quadrantal bisector.
Claim 3
Dependent Claim
17 words
The combination defined in claim 1 wherein the number of radiator groups in each quadrant is eight.
Claim 4
Dependent Claim
83 words
In a radar system including a transmit/receive unit of high-frequency waves, the combination therewith of an antenna comprising a planar array of juxtaposed radiators in the form of mutually parallel slotted waveguides, said array being divided into four quadrants each composed of a multiplicity of radiator groups each provided with an individual transverse feed guide common to all the waveguides thereof, and circuit means connecting the feed guides of the several radiator groups of each quadrant over partly separate paths to said unit.
Claim 5
Dependent Claim
83 words
In a radar system including a transmit/receive unit of high-frequency waves, the combination therewith of an antenna comprising a planar array of juxtaposed radiators in the form of mutually parallel slotted waveguides, said array being divided into four quadrants each composed of a multiplicity of radiator groups each provided with an individual transverse feed guide common to all the waveguides thereof, and circuit means connecting the feed guides of the several radiator groups of each quadrant over partly separate paths to said unit.
Claim 6
Dependent Claim
37 words
The combination defined in claim 3 wherein said circuit means includes an individual junction element for each quadrant linked to the feed guides thereof for additive reception of wave energy picked up by the associated radiator groups.
Claim 7
Dependent Claim
36 words
The combination defined in claim 4 wherein said junction element is a magic-T coupler with a pair of lateral arms linked to the feed guides of the respective quadrant through further magic-T couplers in cascade therewith.
Claim 8
Dependent Claim
17 words
The combination defined in claim 3 wherein each feed guide has opposite ends provided with short-circuit terminations.
Claim 9
Dependent Claim
25 words
The combination defined in claim 3 wherein the paths connecting the feed guides of all quadrants to said unit are of the same electrical length.
Claim 10
Dependent Claim
22 words
The combination defined in claim 3 wherein said array has a generally circular outline, each of said radiator groups being substantially square.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-10-16 | 1982-04-17 | 1982-10-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-10-16 | 1986-04-17 | 1986-10-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-10-16 | 1990-04-17 | 1990-10-17 | $7700.00 | Window Closed / Lapsed |