US3876943A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Impulse noise reduction circuit
Assignee: United States Department of the Navy
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Filing: 1960-02-18
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Granted: 1975-04-08
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Expires: 1980-02-18
Abstract
Abstract 1. In a radio receiver located at some distance from a transmitter emittingignal intelligence which is attenuated and may encounter and combine with atmospheric impulse noise along the transmission path between said receiver and transmitter so that both said signal intelligence and said impulse noise will be coincidently received by said radio receiver as electromagnetic energy, an improved circuit for reducing the noise component of the received signal comprising separate electrically conductive paths, means for dividing said received electromagnetic energy and means for coupling said divided energy into two of said paths respectively, first of said paths having therein as part of said path phase inversion means for phase inversion of said signal passing along said path, amplitude dependent conduction means wherein said signal intelligence is removed from said electromagnetic energy in said first path, and having also in said first path amplitude adder means, a second path having as part thereof said amplitude adder means, whereby said signal passing along said first path which has been phase inverted and said impulse noise in said second path are combined in and the resultant output of said amplitude adder means is substantially signal intelligence, a third path having therein as a part thereof negative feedback means, said third path shunting said amplitude adder means and said amplitude dependent conduction means whereby the signal intelligence in said first path will be further reduced by the negative signal intelligence feedback.
Inventors
- 👤 Arthur D Watt
- 👤 Eugene L Maxwell
- 👤 Robert Marshall Coon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 23:24
CPC Classifications
H; H04; H04B; H04B1/00; H04B1/06; H04B1/10; H04B1/12
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
237 words
In a radio receiver located at some distance from a transmitter emitting signal intelligence which is attenuated and may encounter and combine with atmospheric impulse noise along the transmission path between said receiver and transmitter so that both said signal intelligence and said impulse noise will be coincidently received by said radio receiver as electromagnetic energy, an improved circuit for reducing the noise component of the received signal comprising separate electrically conductive paths, means for dividing said received electromagnetic energy and means for coupling said divided energy into two of said paths respectively, first of said paths having therein as part of said path phase inversion means for phase inversion of said signal passing along said path, amplitude dependent conduction means wherein said signal intelligence is removed from said electromagnetic energy in said first path, and having also in said first path amplitude adder means, a second path having as part thereof said amplitude adder means, whereby said signal passing along said first path which has been phase inverted and said impulse noise in said second path are combined in and the resultant output of said amplitude adder means is substantially signal intelligence, a third path having therein as a part thereof negative feedback means, said third path shunting said amplitude adder means and said amplitude dependent conduction means whereby the signal intelligence in said first path will be further reduced by the negative signal intelligence feedback.
Claim 2
Dependent Claim
237 words
In a radio receiver located at some distance from a transmitter emitting signal intelligence which is attenuated and may encounter and combine with atmospheric impulse noise along the transmission path between said receiver and transmitter so that both said signal intelligence and said impulse noise will be coincidently received by said radio receiver as electromagnetic energy, an improved circuit for reducing the noise component of the received signal comprising separate electrically conductive paths, means for dividing said received electromagnetic energy and means for coupling said divided energy into two of said paths respectively, first of said paths having therein as part of said path phase inversion means for phase inversion of said signal passing along said path, amplitude dependent conduction means wherein said signal intelligence is removed from said electromagnetic energy in said first path, and having also in said first path amplitude adder means, a second path having as part thereof said amplitude adder means, whereby said signal passing along said first path which has been phase inverted and said impulse noise in said second path are combined in and the resultant output of said amplitude adder means is substantially signal intelligence, a third path having therein as a part thereof negative feedback means, said third path shunting said amplitude adder means and said amplitude dependent conduction means whereby the signal intelligence in said first path will be further reduced by the negative signal intelligence feedback.
Claim 3
Dependent Claim
26 words
The improved circuit according to claim 1, wherein said phase inversion means is a phase inversion amplifier and also includes a selectively adjustable phase shift means.
Claim 4
Dependent Claim
30 words
The improved circuit according to claim 2, wherein said amplitude dependent conduction means is a biased diode whereby only signals exceeding the intelligence voltage level will pass through said diode.
Claim 5
Dependent Claim
29 words
The improved circuit according to claim 3, wherein said negative feedback means is a negative feedback amplifier and also includes a narrow band filter tuned to said signal intelligence.
Claim 6
Dependent Claim
19 words
The improved circuit according to claim 4, wherein said second path also includes selectively adjustable amplitude gain control means.
Claim 7
Dependent Claim
16 words
The improved circuit according to claim 5, wherein said phase shift means is a variable capacitor.
Claim 8
Dependent Claim
15 words
The improved circuit according to claim 6, wherein said amplitude gain control is a potentiometer.
Claim 9
Dependent Claim
50 words
The improved circuit according to claim 1, wherein said amplitude dependent conduction means is a biased duo-diode having two diode sections with the cathode of one section and the plate of the other section biased, whereby only signal voltage levels exceeding the intelligence voltage level will pass through said duo-diode.
Claim 10
Dependent Claim
16 words
The improved circuit according to claim 8, wherein said amplitude adder means is an adder circuit.
Claim 11
Dependent Claim
245 words
In a radio receiver located at some distance from a transmitter emitting signal intelligence which is attenuated and may encounter and combine with atmospheric impulse noise along the transmission path between said receiver and transmitter so that both said signal intelligence and said impulse noise will be coincidently received by said radio receiver as electromagnetic energy, an improved circuit for reducing the noise component of the received signal comprising separate electrically conductive paths, means for dividing said received electromagnetic energy and means for coupling said divided energy into two of said paths respectively, first of said paths having therein as part of said path amplitude dependent conduction means wherein said signal intelligence is removed from said electromagnetic energy in said first path, and also having in said first path amplitude adder means, a second path having as part of said second path phase inversion means for phase inversion of said signal passing along said second path and also in said second path said amplitude adder means, whereby said signal passing along said second path which has been phase inverted and said impulse noise on said first path are combined in said amplitude adder means whose resultant output is substantially signal intelligence, a third path having therein as a part thereof negative feedback means, said third path shunting said amplitude adder means and said amplitude dependent conduction means whereby the signal intelligence in said first path will be further reduced by the negative signal intelligence feedback.
Claim 12
Dependent Claim
245 words
In a radio receiver located at some distance from a transmitter emitting signal intelligence which is attenuated and may encounter and combine with atmospheric impulse noise along the transmission path between said receiver and transmitter so that both said signal intelligence and said impulse noise will be coincidently received by said radio receiver as electromagnetic energy, an improved circuit for reducing the noise component of the received signal comprising separate electrically conductive paths, means for dividing said received electromagnetic energy and means for coupling said divided energy into two of said paths respectively, first of said paths having therein as part of said path amplitude dependent conduction means wherein said signal intelligence is removed from said electromagnetic energy in said first path, and also having in said first path amplitude adder means, a second path having as part of said second path phase inversion means for phase inversion of said signal passing along said second path and also in said second path said amplitude adder means, whereby said signal passing along said second path which has been phase inverted and said impulse noise on said first path are combined in said amplitude adder means whose resultant output is substantially signal intelligence, a third path having therein as a part thereof negative feedback means, said third path shunting said amplitude adder means and said amplitude dependent conduction means whereby the signal intelligence in said first path will be further reduced by the negative signal intelligence feedback.
Claim 13
Dependent Claim
241 words
In a radio receiver located at a substantial distance from a transmitter that emits intelligence signals that during transmission are attenuated and may encounter and combine with atmospheric impulse noise signals, that improvement at such receiver which comprises means for receiving the transmitted, modified signals, and amplifying them, detector means, means connecting said receiving and amplifying means to said detecting means for passing the amplified signals to the detector means, and having, in series therein, first means to change the phase of such transmitted signals by 180.degree., then biased means to pass the phase inverted signals solely when they exceed in voltage that of such amplified intelligence signals, and then means to add signals, a negative feedback amplifier connecting the output side of the adding means to the input side of said bias means, for returning output adding means intelligence signals to combine with the incoming signal to said bias means in phase opposition means connecting said signal receiving and amplifying means to said adding means, said adding means being operable to combine the two inverted and uninverted signals delivered thereto and passing the resultant combination signal to said detector, whereby when the phase inverted signals are combined in the adding means with the uninverted mixed signal, the noise signals which only passed through the biased means, will materially destroy the noise signals in the uninverted signals and the remaining signal including the intelligence signals will be delivered to said detector.
Claim 14
Dependent Claim
241 words
In a radio receiver located at a substantial distance from a transmitter that emits intelligence signals that during transmission are attenuated and may encounter and combine with atmospheric impulse noise signals, that improvement at such receiver which comprises means for receiving the transmitted, modified signals, and amplifying them, detector means, means connecting said receiving and amplifying means to said detecting means for passing the amplified signals to the detector means, and having, in series therein, first means to change the phase of such transmitted signals by 180.degree., then biased means to pass the phase inverted signals solely when they exceed in voltage that of such amplified intelligence signals, and then means to add signals, a negative feedback amplifier connecting the output side of the adding means to the input side of said bias means, for returning output adding means intelligence signals to combine with the incoming signal to said bias means in phase opposition means connecting said signal receiving and amplifying means to said adding means, said adding means being operable to combine the two inverted and uninverted signals delivered thereto and passing the resultant combination signal to said detector, whereby when the phase inverted signals are combined in the adding means with the uninverted mixed signal, the noise signals which only passed through the biased means, will materially destroy the noise signals in the uninverted signals and the remaining signal including the intelligence signals will be delivered to said detector.
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) | 1978-04-07 | 1978-10-07 | 1979-04-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-07 | 1982-10-07 | 1983-04-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-07 | 1986-10-07 | 1987-04-08 | $7700.00 | Window Closed / Lapsed |