Patent US4774441A successfully refreshed from Google Patents.
US3679987A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Active rc wave transmission network using single amplifier to achieve all-pass transfer function
Assignee: AT&T Inc
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Filing: 1970-11-24
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Granted: 1972-07-25
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Expires: 1990-11-24
Abstract
Abstract A resistance-capacitance network in circuit with a single operational amplifier provides an all-pass 360* phase transfer function. The single amplifier is arranged for operation in the differential mode with the signal to be controlled applied directly to the inverting input and through an amplitude shaping network to the noninverting input. Depending on whether the shaping network is loaded with a parallel or series resistancecapacitance combination parasitic phase shift or signal loss in the amplifier can also be compensated.
Inventors
- 👤 George Samson Moschytz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 15:11
CPC Classifications
G; G01; G01S; G01S1/00; G01S1/02; G01S13/00; G01S13/88; G01S13/93; G01S13/937
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
203 words
A wave trAnsmission network for controlling the phasefrequency characteristic of broadband signals without altering the amplitude-frequency characteristic thereof comprising a differential amplifier having inverting and noninverting inputs and an output; a frequency-determining circuit in series between an input point for said network and the noninverting input of said amplifier and in positive feedback relationship to the output of said amplifier further comprising two signal paths in parallel between input and output terminals, one of said paths including equal resistive elements in series between a first junction and said input and output terminals and the other of said paths including equal capacitive elements in series between a second junction and said input and output terminals, and two shunt paths between said first and second junctions and a common terminal, the shunt path connected to said first junction including a capacitive element of twice the value of said equal capacitive elements and the shunt path connected to said second junction including a resistive element of half the value of said equal resistive elements; a resistive feedback connection between the output and inverting input of said amplifier; and a direct resistive connection between the input point of said network and the inverting input of said amplifier.
Claim 2
Dependent Claim
203 words
A wave trAnsmission network for controlling the phasefrequency characteristic of broadband signals without altering the amplitude-frequency characteristic thereof comprising a differential amplifier having inverting and noninverting inputs and an output; a frequency-determining circuit in series between an input point for said network and the noninverting input of said amplifier and in positive feedback relationship to the output of said amplifier further comprising two signal paths in parallel between input and output terminals, one of said paths including equal resistive elements in series between a first junction and said input and output terminals and the other of said paths including equal capacitive elements in series between a second junction and said input and output terminals, and two shunt paths between said first and second junctions and a common terminal, the shunt path connected to said first junction including a capacitive element of twice the value of said equal capacitive elements and the shunt path connected to said second junction including a resistive element of half the value of said equal resistive elements; a resistive feedback connection between the output and inverting input of said amplifier; and a direct resistive connection between the input point of said network and the inverting input of said amplifier.
Claim 3
Dependent Claim
61 words
The wave transmission network defined in claim 1 in which the output terminal of said frequency is loaded with a determining circuit parallel combination of a resistive and a capacitive element whose values are related to those of said equal resistive and capacitive elements by equal scaling factors respectively dividing and multiplying the values of said equal resistive and capacitive elements.
Claim 4
Dependent Claim
60 words
The wave transmission network defined in claim 1 in which the output terminal of said frequency-determining circuit is loaded with a series combination of a resistive and a capacitive element whose values are related to those of said equal resistive and capacitive elements by equal scaling factors respectively dividing and multiplying the values of said equal resistive and capacitive elements.
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) | 1975-07-25 | 1976-01-24 | 1976-07-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-25 | 1980-01-24 | 1980-07-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-25 | 1984-01-24 | 1984-07-25 | $7700.00 | Window Closed / Lapsed |