Patent US3507991A successfully refreshed from Google Patents.
US3507991A
Expired / Lapsed
US
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Tracking system apparatus and signal processing methods
Assignee: Boeing North American Inc
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Filing: 1967-07-27
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Granted: 1970-04-21
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Expires: 1987-07-27
Abstract
No abstract record available.
Inventors
- 👤 Lawrence J Scotchie
- 👤 Wallace W Windle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 20:55
CPC Classifications
F; F41; F41G; F41G3/00; F41G3/14; F41G3/16; F41G3/165; G; G01; G01S; G01S3/00; G01S3/78; G01S3/782; G01S3/785; G01S3/786; G01S3/7864
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US3043907A
Cited
US2774964A
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US2877354A
Cited
US3010024A
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US3199400A
Cited
US3257505A
Cited
US3341653A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-04-20 | 1973-10-20 | 1974-04-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-04-20 | 1977-10-20 | 1978-04-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-04-20 | 1981-10-20 | 1982-04-21 | $7700.00 | Window Closed / Lapsed |