US3641433A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Transmitted reference synchronization system
Assignee: United States Department of the Air Force
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Filing: 1969-06-09
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Granted: 1972-02-08
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Expires: 1989-06-09
Abstract
Abstract A transmitted reference synchronization system which combines a high process gain transmitted reference communication link with a fixed time delay automatic synchronization technique to allow a correlation process to be accomplished at the origination end of the link with extremely accurate and completely automatic synchronization.
Inventors
- 👤 Ralph W Mifflin
- 👤 Joseph P Wheeler
- 👤 Joseph T Massoud
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 02:11
CPC Classifications
H; H04; H04L; H04L1/00; H04L1/12; H04L7/00; H04L7/04; H04L7/041; H04L7/043
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
271 words
A transmitted reference synchronization system for a link having an origination end and a second end displaced therefrom wherein one of the ends of the link is in constant motion in relation to the other end comprising means to generate a noise signal at said origination end, first means to translate said noise signal to a preselected RF transmission frequency to provide a first translated signal, said first translating means consisting of a local oscillator providing a preselected frequency signal and a first mixer simultaneously receiving said noise signal and said preselectEd frequency signal, first antenna means located at said origination end to transmit said first translated signal toward said second end, second antenna means located at said second end receiving the transmitted first translated signal to provide a first received signal, second means to translate said first received signal to a predetermined offset RF frequency to provide a second translated signal, means to modulate said second translated signal with an information signal to provide a modulated noise signal, said modulated noise signal being transmitted by said second antenna means for reception by said first antenna means to provide a second received signal, a second mixer receiving simultaneously said second received signal and said preselected frequency signal to provide an output signal for correlation purposes, means at said origination end to delay said noise signal a predetermined period to provide a delayed noise signal, and means to correlate said delayed noise signal with said output signal, the correlation occurring automatically when the relative range between said origination and second ends of said link represents a time difference equal to the delay.
Claim 2
Dependent Claim
271 words
A transmitted reference synchronization system for a link having an origination end and a second end displaced therefrom wherein one of the ends of the link is in constant motion in relation to the other end comprising means to generate a noise signal at said origination end, first means to translate said noise signal to a preselected RF transmission frequency to provide a first translated signal, said first translating means consisting of a local oscillator providing a preselected frequency signal and a first mixer simultaneously receiving said noise signal and said preselectEd frequency signal, first antenna means located at said origination end to transmit said first translated signal toward said second end, second antenna means located at said second end receiving the transmitted first translated signal to provide a first received signal, second means to translate said first received signal to a predetermined offset RF frequency to provide a second translated signal, means to modulate said second translated signal with an information signal to provide a modulated noise signal, said modulated noise signal being transmitted by said second antenna means for reception by said first antenna means to provide a second received signal, a second mixer receiving simultaneously said second received signal and said preselected frequency signal to provide an output signal for correlation purposes, means at said origination end to delay said noise signal a predetermined period to provide a delayed noise signal, and means to correlate said delayed noise signal with said output signal, the correlation occurring automatically when the relative range between said origination and second ends of said link represents a time difference equal to the delay.
Claim 3
Dependent Claim
40 words
A transmitted reference synchronization system as described in claim 1 including first means to filter the first translated signal to a predetermined bandwidth prior to transmittal thereof, and second means to filter the second translated signal prior to transmittal thereof.
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) | 1975-02-07 | 1975-08-09 | 1976-02-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-02-07 | 1979-08-09 | 1980-02-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-02-07 | 1983-08-09 | 1984-02-08 | $7700.00 | Window Closed / Lapsed |