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US4048579A Expired / Lapsed US ⏱️ 0.0 years remaining

Feed-forward amplifier

Assignee: Telefonaktiebolaget LM Ericsson AB
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Filing: 1976-07-26
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Granted: 1977-09-13
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Expires: 1996-07-26
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Abstract

Abstract A feed-forward amplifier with an input arranged to receive wide-band signals and an output to supply a linearly amplified version of these has two parallel signal paths arranged between such input and output, one of the signal paths includes a cascade connection of a signal amplifier and a delay network and the second signal path includes an error amplifier, an error extraction circuit having a directional coupler in which an input side has a first pair of conjugate first and second ports and is connected partly to the input of the feed-forward amplifier and partly to an output of the signal amplifier and an output side has a second pair of conjugate third and fourth ports, the fourth port being connected to an input of the error amplifier, and an error injection circuit which has a first and a second input connected to an output of the delay network and to an output of the error amplifier, respectively and an output connected to the output of the feed-forward amplifier, the error extraction circuit having the third port of the directional coupler connected to an input of the signal amplifier and a summation circuit having a first and second input connected to the input of the feed-forward amplifier and to the output of the signal amplifier, respectively, and an output connected to the second port of the directional coupler.

Inventors

  • 👤 Rolf Christer Carlsson

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 15:26
CPC Classifications
H; H03; H03F; H03F1/00; H03F1/42; H03F1/32; H03F1/3223; H03F1/3229

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 200 words
A feed-forward amplifier for receiving an input signal and emitting an output signal comprising: a main signal amplifier having an input port and an output port; first signal processing means for forming a difference signal between the received input signal and the signal at the output port of said main signal amplifier; dividing means for dividing the difference signal into first and second difference signal components and having first and second output ports for emitting the first and second difference signal components respectively; first connecting means for connecting the first output port of said dividing means to the input port of said main signal amplifier whereby the first difference signal component is fed to said main signal amplifier; and second signal processing means having first and second input ports and an output port for arithmetically combining the signals received at its input ports and emitting the result signal at its output port; second connecting means for connecting the output of said main signal amplifier to the first input port of said second signal processing means; and third connecting means for connecting the second output port of said dividing means to the second input port of said second signal processing means.
Claim 2
Dependent Claim 200 words
A feed-forward amplifier for receiving an input signal and emitting an output signal comprising: a main signal amplifier having an input port and an output port; first signal processing means for forming a difference signal between the received input signal and the signal at the output port of said main signal amplifier; dividing means for dividing the difference signal into first and second difference signal components and having first and second output ports for emitting the first and second difference signal components respectively; first connecting means for connecting the first output port of said dividing means to the input port of said main signal amplifier whereby the first difference signal component is fed to said main signal amplifier; and second signal processing means having first and second input ports and an output port for arithmetically combining the signals received at its input ports and emitting the result signal at its output port; second connecting means for connecting the output of said main signal amplifier to the first input port of said second signal processing means; and third connecting means for connecting the second output port of said dividing means to the second input port of said second signal processing means.
Claim 3
Dependent Claim 15 words
The feed-forward amplifier of claim 1 wherein said first signal processing means is a transformer.
Claim 4
Dependent Claim 16 words
The feed-forward amplifier of claim 1 wherein said second signal processing means is a directional coupler.
Claim 5
Dependent Claim 14 words
The feed-forward amplifier of claim 1 wherein said dividing means is a directional coupler.
Claim 6
Dependent Claim 16 words
The feed-forward amplifier of claim 2 wherein said third connecting means is an error signal amplifier.
Claim 7
Dependent Claim 16 words
The feed-forward amplifier of claim 1 wherein said second connecting means is a signal delaying means.
Claim 8
Dependent Claim 23 words
The feed-forward amplifier of claim 6 wherein said first signal processing means is a transformer and said dividing means is a directional coupler.
Claim 9
Dependent Claim 16 words
The feed-forward amplifier of claim 7 wherein said second signal processing means is another directional coupler.

References Cited (Backward Citations)

US3541467A Cited
US3624532A Cited
US3815040A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-09-12 1981-03-14 1981-09-13 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-09-12 1985-03-14 1985-09-13 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-09-12 1989-03-14 1989-09-13 $7700.00 Window Closed / Lapsed

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