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US2639422A
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Forward radar echo-ranging method and system
Assignee: Collins Radio Co
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Filing: 1949-03-08
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Granted: 1953-05-19
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Expires: 1969-03-08
Abstract
No abstract record available.
Inventors
- 👤 Donald B Harris
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 04:50
CPC Classifications
G; G01; G01S; G01S13/00; G01S13/02; G01S13/06; G01S13/46
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1981884A
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US2409448A
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US2420408A
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US2408048A
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US2399017A
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US2463476A
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US2535038A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-05-18 | 1956-11-17 | 1957-05-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-05-18 | 1960-11-17 | 1961-05-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-05-18 | 1964-11-17 | 1965-05-19 | $7700.00 | Window Closed / Lapsed |