US4547746A
Expired / Lapsed
US
⏱️ 0.0 years remaining
VSWR Tolerant linear power amplifier
Assignee: Boeing North American Inc
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Filing: 1984-04-09
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Granted: 1985-10-15
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Expires: 2004-04-09
Abstract
Abstract There is disclosed a power amplifier which is useful in broadband systems having load impedances with VSWRs up to a range of 2:1 or 2.5:1. The power amplifier is constructed to change its operating conditions to match the load as presented at the output of the amplifier and is particularly useful in systems employing frequency hopping requiring broadband construction. A feedback signal from the output of the amplifier is constructed to provide a signal representing the difference between forward and reflected power which is compared in a multiplier with a signal representing current flow in the power amplifier to produce a control voltage for adjusting the supply voltage of transistors forming the power amplifier. Thereafter, if the load impedance changes, the supply voltage is also changed to minimize dissipation and maintain the efficiency of the amplifier substantially constant.
Inventors
- 👤 Alan R. Erickson
- 👤 Marvin W. Heidt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 18:18
CPC Classifications
H; H03; H03G; H03G3/00; H03G3/20; H03G3/30; H03G3/3036; H03G3/3042; H03F; H03F1/00; H03F1/02; H03F1/0205; H03F1/0211; H03F1/0216; H03F1/34; H03F1/345; H03G3/004; H03F2200/00; H03F2200/504
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
90 words
An amplifying system comprising: an amplifier having an input, an output, and means for receiving a supply voltage; a load coupled to the output of said amplifier; means coupled between the output of said amplifier and said load for providing a signal representing power; means coupled to sense current provided to said amplifier from said supply voltage to provide an output signal; means for dividing said signal representing power by said output signal to provide a control signal; and means responsive to said control signal for varying said supply voltage.
Claim 2
Dependent Claim
90 words
An amplifying system comprising: an amplifier having an input, an output, and means for receiving a supply voltage; a load coupled to the output of said amplifier; means coupled between the output of said amplifier and said load for providing a signal representing power; means coupled to sense current provided to said amplifier from said supply voltage to provide an output signal; means for dividing said signal representing power by said output signal to provide a control signal; and means responsive to said control signal for varying said supply voltage.
Claim 3
Dependent Claim
58 words
The system of claim 1 wherein said means for providing said signal representing power comprises a directional coupler having a first output representing reflected power and a second output representing forward power and a comparator means coupled to said first and second output for subtracting said reflected power from said forward power to provide said signal representing power.
Claim 4
Dependent Claim
162 words
In a broadband frequency hopping system having an audio source, a modulator responsive to said audio source for modulating a carrier frequency, a means for changing said carrier frequency in response to a frequency control, an amplifier for amplifying said carrier frequency, and an antenna coupled to transmit said amplified modulated carrier frequency, the improvement in said amplifier comprising: an amplifier, having an input, output, and means for receiving a supply voltage; a variable voltage supply coupled to said means for receiving a supply voltage; a load coupled to the output of said amplifier; means coupled between the output of said amplifier and said load for providing a signal representing power; means coupled to sense current provided to said amplifier from said variable voltage supply to provide an output signal; means for dividing said signal representing power by said output signal to provide a control signal; and means responsive to said control signal for changing the voltage of said variable voltage supply.
Claim 5
Dependent Claim
162 words
In a broadband frequency hopping system having an audio source, a modulator responsive to said audio source for modulating a carrier frequency, a means for changing said carrier frequency in response to a frequency control, an amplifier for amplifying said carrier frequency, and an antenna coupled to transmit said amplified modulated carrier frequency, the improvement in said amplifier comprising: an amplifier, having an input, output, and means for receiving a supply voltage; a variable voltage supply coupled to said means for receiving a supply voltage; a load coupled to the output of said amplifier; means coupled between the output of said amplifier and said load for providing a signal representing power; means coupled to sense current provided to said amplifier from said variable voltage supply to provide an output signal; means for dividing said signal representing power by said output signal to provide a control signal; and means responsive to said control signal for changing the voltage of said variable voltage supply.
Claim 6
Dependent Claim
42 words
The system of claim 3 wherein said means for changing the variable voltage is constructed and arranged to change said voltage in such a manner as to maintain a substantially constant efficiency of the amplifier in response to variations in the load.
Claim 7
Dependent Claim
35 words
The system of claim 3 wherein said means for changing the voltage increases the voltage in response to an increase in load impedance and decreases the voltage in response to a decrease in load impedance.
Claim 8
Dependent Claim
14 words
The system of claim 4 wherein said amplifier is a class AB transistor amplifier.
Claim 9
Dependent Claim
15 words
The system of claim 5 wherein said amplifier is a high power radio frequency amplifier.
Claim 10
Dependent Claim
15 words
The system of claim 1 wherein said means for sensing current comprises a differential amplifier.
Claim 11
Dependent Claim
126 words
An amplifying system comprising: an amplifier having an input, an output, and means for receiving a supply voltage; a load coupled to the output of said amplifier; means coupled between the output of said amplifier and said load for providing a signal representing power; means coupled to sense current provided to said amplifier from said supply voltage to provide an output signal and including a resistor coupled between said supply voltage and said amplifier, and a differential amplifier having first and second inputs coupled to terminals of said resistor to sense said current and provide said output signal; means for dividing said signal representing power by said output signal to provide a control signal; and means responsive to said control signal for varying said supply voltage.
Claim 12
Dependent Claim
126 words
An amplifying system comprising: an amplifier having an input, an output, and means for receiving a supply voltage; a load coupled to the output of said amplifier; means coupled between the output of said amplifier and said load for providing a signal representing power; means coupled to sense current provided to said amplifier from said supply voltage to provide an output signal and including a resistor coupled between said supply voltage and said amplifier, and a differential amplifier having first and second inputs coupled to terminals of said resistor to sense said current and provide said output signal; means for dividing said signal representing power by said output signal to provide a control signal; and means responsive to said control signal for varying said supply voltage.
Claim 13
Dependent Claim
200 words
In a broadband frequency hopping system having an audio source, a modulator responsive to said audio source for modulating a carrier frequency, a means for changing said carrier frequency in response to a frequency control, an amplifier for amplifying said carrier frequency, and an antenna coupled to transmit said amplified modulated carrier frequency, the improvement in said amplifier comprising: an amplifier, having an input, output, and means for receiving a supply voltage; a variable voltage supply coupled to said means for receiving a supply voltage; a load coupled to the output of said amplifier; and means responsive to a variation of said load for changing the voltage of said variable voltage supply, said means for changing the voltage comprising a directional coupler coupled between the output of said amplifier and the load and having first and second outputs representing forward power and reflected power, means for subtracting reflected power from forward power to provide a power signal, means for sensing current provided from said variable voltage supply to said amplifier and providing an output signal, and means for dividing said power signal by said output signal to provide a control voltage for changing the voltage of said variable voltage supply.
Claim 14
Dependent Claim
200 words
In a broadband frequency hopping system having an audio source, a modulator responsive to said audio source for modulating a carrier frequency, a means for changing said carrier frequency in response to a frequency control, an amplifier for amplifying said carrier frequency, and an antenna coupled to transmit said amplified modulated carrier frequency, the improvement in said amplifier comprising: an amplifier, having an input, output, and means for receiving a supply voltage; a variable voltage supply coupled to said means for receiving a supply voltage; a load coupled to the output of said amplifier; and means responsive to a variation of said load for changing the voltage of said variable voltage supply, said means for changing the voltage comprising a directional coupler coupled between the output of said amplifier and the load and having first and second outputs representing forward power and reflected power, means for subtracting reflected power from forward power to provide a power signal, means for sensing current provided from said variable voltage supply to said amplifier and providing an output signal, and means for dividing said power signal by said output signal to provide a control voltage for changing the voltage of said variable voltage supply.
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) | 1988-10-14 | 1989-04-15 | 1989-10-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-10-14 | 1993-04-15 | 1993-10-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-10-14 | 1997-04-15 | 1997-10-15 | $7700.00 | Window Closed / Lapsed |