US3555554A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cavity-backed spiral antenna with mode suppression
Assignee: GTE Sylvania Inc
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Filing: 1969-03-03
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Granted: 1971-01-12
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Expires: 1989-03-03
Abstract
Abstract THIS PLANAR UNIDIRECTIONAL CAVITY-BACKED SPIRAL ANTENNA HAS A CYLINDRICAL RESISTANCE CARD IN THE CAVITY COAXIAL WITH THE CENTER CONDUCTOR THEREOF TO SUPPRESS MODES OF PROPAGATION OF ELECTROMAGNETIC WAVES IN THE CAVITY OTHER THAN THE DOMINANT MODE.
Inventors
- 👤 Samuel Chung-Shu Kuo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 09:15
CPC Classifications
H; H01; H01Q; H01Q9/00; H01Q9/04; H01Q9/16; H01Q9/26; H01Q9/27
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-01-11 | 1974-07-13 | 1975-01-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-01-11 | 1978-07-13 | 1979-01-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-01-11 | 1982-07-13 | 1983-01-12 | $7700.00 | Window Closed / Lapsed |