US3568206A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Transmission line loaded annular slot antenna
Assignee: Northrop Grumman Corp
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Filing: 1968-02-15
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Granted: 1971-03-02
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Expires: 1988-02-15
Abstract
Abstract A probe is connected to the bottom of a cavity, and a spiraled conductor is connected to the top of the probe, where the outer turns of the spiral are spaced from the cavity top edges to form an electrically small slot. This antenna is fed from the cavity bottom near the probe by the extension of the center conductor of a terminated coaxial line.
Inventors
- 👤 Austin R Sisson
- 👤 Dale W Milligan
- 👤 Robert D Wanselow
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 05:44
CPC Classifications
H; H01; H01Q; H01Q9/00; H01Q9/04; H01Q9/16; H01Q9/26; H01Q9/27
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
76 words
An antenna comprising a conductive cavity, a spiral conductor lying substantially in the plane of the outer opening of Said cavity with the outermost portion of said spiral conductor spaced from the sides of said cavity to form substantially an annular slot, and a conductive probe member electrically connecting the inner end of said spiral to the bottom of said cavity, the nominal diameter of said cavity being only approximately 0.05 wavelength at the opening frequency.
Claim 2
Dependent Claim
76 words
An antenna comprising a conductive cavity, a spiral conductor lying substantially in the plane of the outer opening of Said cavity with the outermost portion of said spiral conductor spaced from the sides of said cavity to form substantially an annular slot, and a conductive probe member electrically connecting the inner end of said spiral to the bottom of said cavity, the nominal diameter of said cavity being only approximately 0.05 wavelength at the opening frequency.
Claim 3
Dependent Claim
31 words
Apparatus in accordance with claim 1 including a first transmission line feed connection at the bottom of said cavity and a second such connection at said spiral conductor near said probe.
Claim 4
Dependent Claim
30 words
Apparatus in accordance with claim 1 including a first transmission line feed connection at the bottom of said cavity and a second such connection to the side of said probe.
Claim 5
Dependent Claim
14 words
Apparatus in accordance with claim 1 including tuning means connected to said spiral conductor.
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) | 1974-03-01 | 1974-08-31 | 1975-03-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-03-01 | 1978-08-31 | 1979-03-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-03-01 | 1982-08-31 | 1983-03-02 | $7700.00 | Window Closed / Lapsed |