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US2817828A
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Multifrequency high speed signaling system employing pulses of signaling currents ofpredetermined duration based on orthogonal functions
Assignee: AT&T Inc
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Filing: 1953-10-07
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Granted: 1957-12-24
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Expires: 1973-10-07
Abstract
No abstract record available.
Inventors
- 👤 John H Mcguigan
- 👤 Orlando J Murphy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 03:21
CPC Classifications
H; H04; H04Q; H04Q3/00; H04Q1/00; H04Q1/18; H04Q1/30; H04Q1/44; H04Q1/444; H04Q1/45; H04Q1/453
Claims Analysis
Total Claims: 0
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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) | 1960-12-23 | 1961-06-24 | 1961-12-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-12-23 | 1965-06-24 | 1965-12-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-12-23 | 1969-06-24 | 1969-12-24 | $7700.00 | Window Closed / Lapsed |