Patent US3696429A successfully refreshed from Google Patents.
US3696429A
Expired / Lapsed
US
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Signal cancellation system
Assignee: Cutler Hammer Inc
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Filing: 1971-05-24
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Granted: 1972-10-03
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Expires: 1991-05-24
Abstract
Abstract An unwanted r-f signal produced on a receiver line by a nearby transmitter is reduced by adding to it a sample of the transmitted signal, automatically adjusted in phase and amplitude to cancel the unwanted signal.
Inventors
- 👤 Frank J Tressa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 07:52
CPC Classifications
H; H04; H04B; H04B7/00; H04B7/14; H04B7/15; H04B7/155; H04B7/15564; H04B7/15585; G; G01; G01S; G01S7/00; G01S7/02; G01S7/03; G01S7/038; H03; H03H; H03H7/00; H03H7/48; H04B1/00; H04B1/38; H04B1/40; H04B1/50; H04B1/52; H04B1/525
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
154 words
A system for cancelling an undesired r-f signal that is produced on a receiver line by a source of interference, comprising: a. means for providing a signal sample portion of the output of said source, b. means for separating said signal sample into first and second quadrature components, c. first control means for controlling the amplitude and phase sense of said first quadrature component and second control means for controlling the amplitude and phase sense of said second quadrature component, d. means for applying said controlled quadrature components to said receiver line, for combination with said undesired signal to produce a resultant r-f signal, e. first and second demodulator means for producing respective outputs corresponding to quadrature components of said resultant signal, and f. means responsive to said demodulator outputs respectively for adjusting said first and second amplitude and phase sense control means to substantially nullify respective quadrature components of said undesired r-f signal.
Claim 2
Independent Claim
154 words
A system for cancelling an undesired r-f signal that is produced on a receiver line by a source of interference, comprising: a. means for providing a signal sample portion of the output of said source, b. means for separating said signal sample into first and second quadrature components, c. first control means for controlling the amplitude and phase sense of said first quadrature component and second control means for controlling the amplitude and phase sense of said second quadrature component, d. means for applying said controlled quadrature components to said receiver line, for combination with said undesired signal to produce a resultant r-f signal, e. first and second demodulator means for producing respective outputs corresponding to quadrature components of said resultant signal, and f. means responsive to said demodulator outputs respectively for adjusting said first and second amplitude and phase sense control means to substantially nullify respective quadrature components of said undesired r-f signal.
Claim 3
Dependent Claim
76 words
The invention set forth in claim 1, further including: a. means for modulating said source with a tag signal, whereby the outputs of said first and second demodulator means contain respective tag signal components, b. first and second means responsive respectively to said tag signal components to produce respective first and second d-c control signals, and c. means for applying said d-c control signals to said first and second amplitude and phase sense control means, respectively.
Claim 4
Dependent Claim
31 words
The invention set forth in claim 2, wherein said tag signal is of a frequency outside the band of modulating signals that are impressed on said r-f signal for carrying intelligence.
Claim 5
Dependent Claim
20 words
The invention set forth in claim 2, wherein the modulation of said source by said tag signal is amplitude modulation.
Claim 6
Dependent Claim
33 words
The invention set forth in claim 2, wherein said means responsive to said tag signal components respectively each include a synchronous detector connected to receive said tag signal as a switching control input.
References Cited (Backward Citations)
US1703142A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-10-03 | 1976-04-03 | 1976-10-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-03 | 1980-04-03 | 1980-10-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-03 | 1984-04-03 | 1984-10-03 | $7700.00 | Window Closed / Lapsed |