US3663886A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Parametric amplifiers with idler circuit feedback
Assignee: National Aeronautics and Space Administration
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Filing: 1970-12-17
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Granted: 1972-05-16
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Expires: 1990-12-17
Abstract
Abstract Two parametric amplifiers connected such that there is feedback from the idler circuit of one of the amplifiers to the idler circuit of the other amplifier to effect noise reduction.
Inventors
- 👤 Hans-Juergen C Blume
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 03:45
CPC Classifications
H; H03; H03F; H03F7/00
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
174 words
Apparatus for reducing the internally generated noise of a first parametric amplifier having input, pump and idler circuits with terminals for its signal input and pump circuits comprising: means for providing a terminal to the idler circuit of said first parametric amplifier; a second parametric amplifier like said first parametric amplifier including said terminal to the idler circuit; phase shifting means connected between the idler circuit terminals of said first and second parametric amplifiers; means for providing power to the terminals of the pump circuits of said first and second parametric amplifiers; means for applying an input signal to the signal input circuit terminal of said first parametric amplifier; and means for applying at least a part of the amplified signal from said first parametric amplifier to the signal input circuit terminal of said second parametric amplifier whereby the resulting signal generated in the idler circuit of said second parametric amplifier is fed back to the idler circuit of said first parametric amplifier to reduce the noise internally generated in said first parametric amplifier.
Claim 2
Dependent Claim
174 words
Apparatus for reducing the internally generated noise of a first parametric amplifier having input, pump and idler circuits with terminals for its signal input and pump circuits comprising: means for providing a terminal to the idler circuit of said first parametric amplifier; a second parametric amplifier like said first parametric amplifier including said terminal to the idler circuit; phase shifting means connected between the idler circuit terminals of said first and second parametric amplifiers; means for providing power to the terminals of the pump circuits of said first and second parametric amplifiers; means for applying an input signal to the signal input circuit terminal of said first parametric amplifier; and means for applying at least a part of the amplified signal from said first parametric amplifier to the signal input circuit terminal of said second parametric amplifier whereby the resulting signal generated in the idler circuit of said second parametric amplifier is fed back to the idler circuit of said first parametric amplifier to reduce the noise internally generated in said first parametric amplifier.
Claim 3
Dependent Claim
56 words
Apparatus according to claim 1 wherein said means for applying an input signal to the signal input circuit terminal includes a signal source applied through a first circulator to the signal input circuit terminal of said first parametric amplifier whereby the amplfied signal from the first parametric amplifier appears at the output of said first circulator.
Claim 4
Dependent Claim
51 words
Apparatus according to claim 2 wherein said means for applying at least a part of the amplified signal from said first parametric amplifier to the signal input circuit terminal of said second parametric amplifier includes a directional coupler which diverts a part of the amplified signal to the second parametric amplifier.
Claim 5
Dependent Claim
28 words
Apparatus according to claim 3 wherein said diverted parts of said amplified signal is applied through a second circulator to the iNput terminal of said second parametric amplifier.
Claim 6
Dependent Claim
18 words
Apparatus according to claim 4 wherein a matching load is connected to the output of said second circulator.
Claim 7
Dependent Claim
59 words
Apparatus according to claim 2 wherein said means for applying at least a part of the amplified signal from said first parametric amplifier to the signal input circuit terminal of said second parametric amplifier includes a second circulator whose input is connected to receive at least a part of the amplified signal from the output of said first circulator.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-05-16 | 1975-11-15 | 1976-05-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-16 | 1979-11-15 | 1980-05-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-16 | 1983-11-15 | 1984-05-16 | $7700.00 | Window Closed / Lapsed |