US3346864A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Underground antenna
Assignee: Northrop Grumman Corp
•
Filing: 1966-09-09
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Granted: 1967-10-10
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Expires: 1986-09-09
Abstract
No abstract record available.
Inventors
- 👤 Gregory J Harmon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 15:07
CPC Classifications
H; H01; H01Q; H01Q1/00; H01Q1/04
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
113 words
AN UNDERGROUND ANTENNA IN A MOUNTAIN OR LARGE HILL HAVING A ROCK SUB-SURFACE AND A SURFACE SLOPE GREATER THAN ABOUT 10* IN A DESIRED AZIMUTH DIRECTION WHICH COMPRISES A RESONANT ANTENNA IN SAID ROCK SUB-SURFACE, THE DEPTH OF SAID ANTENNA BEING AT LEAST APPROXIMATELY ONETENTH WAVELENGTH IN THE MEDIUM AT THE OPERATING FREQUENCY, THE ELECTRICALLY CONDUCTIVE SURFACE OF SAID ANTENNA BEING CLOSELY ADJACENT SAID SUB-SURFACE ROCK IN CLOSE COUPLING RELATIONSHIP THEREWITH, SAID ANTENNA HAVING A POSITION AND ORIENTATION PREDETERMINED TO YIELD A RADIATION PATTERN HAVING A MAJOR LOBE DIRECTED TOWARD SAID SURFACE SLOPE AND A REFRACTED BEAM IN AIR HAVING NEAR-MAXIMAL RADIATION VECTORS AT SMALL ANGLES TO THE HORIZONTAL IN SAID DESIRED DIRECTION.
Claim 2
Dependent Claim
113 words
AN UNDERGROUND ANTENNA IN A MOUNTAIN OR LARGE HILL HAVING A ROCK SUB-SURFACE AND A SURFACE SLOPE GREATER THAN ABOUT 10* IN A DESIRED AZIMUTH DIRECTION WHICH COMPRISES A RESONANT ANTENNA IN SAID ROCK SUB-SURFACE, THE DEPTH OF SAID ANTENNA BEING AT LEAST APPROXIMATELY ONETENTH WAVELENGTH IN THE MEDIUM AT THE OPERATING FREQUENCY, THE ELECTRICALLY CONDUCTIVE SURFACE OF SAID ANTENNA BEING CLOSELY ADJACENT SAID SUB-SURFACE ROCK IN CLOSE COUPLING RELATIONSHIP THEREWITH, SAID ANTENNA HAVING A POSITION AND ORIENTATION PREDETERMINED TO YIELD A RADIATION PATTERN HAVING A MAJOR LOBE DIRECTED TOWARD SAID SURFACE SLOPE AND A REFRACTED BEAM IN AIR HAVING NEAR-MAXIMAL RADIATION VECTORS AT SMALL ANGLES TO THE HORIZONTAL IN SAID DESIRED DIRECTION.
References Cited (Backward Citations)
US2638588A
Cited
US3183510A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1970-10-09 | 1971-04-10 | 1971-10-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-10-09 | 1975-04-10 | 1975-10-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-10-09 | 1979-04-10 | 1979-10-10 | $7700.00 | Window Closed / Lapsed |