Patent US3791585A successfully refreshed from Google Patents.
US6765440B2
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US
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Model-based feed-forward linearization of amplifiers
Assignee: Commscope Technologies LLC
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Filing: 2002-12-18
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Granted: 2004-07-20
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Expires: 2022-12-18
Abstract
Abstract The signal generated by a high-power amplifier (HPA) operating in its non-linear region is linearized by an amplifier circuit using feed-forward compensation in which an auxiliary channel relies on a model of the HPA to generate an auxiliary signal that is combined with the HPA output to generate an amplified linearized output signal. The amplifier circuit may be implemented with a pre-distorter in the main amplifier channel to linearize the HPA using both pre-compensation and feed-forward compensation. Using the HPA model in the auxiliary channel enables the auxiliary signal to be generated without directly relying on the HPA output. This enables the amplifier circuit to be implemented without having to delay the high-power HPA output signal prior to being synchronously combined with the auxiliary signal. In preferred embodiments, the auxiliary channel signal is generated using a relatively low-power amplifier operating in its linear region.
Inventors
- 👤 Rajiv Chandrasekaran
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 07:01
CPC Classifications
H; H03; H03F; H03F1/00; H03F1/32; H03F1/3223; H03F1/3229; H03F1/3241; H03F1/3247
Claims Analysis
Total Claims: 51
Claim 1
Independent Claim
138 words
An amplifier circuit adapted to generate a linearized amplified output signal from an input signal, the amplifier circuit comprising: a main channel adapted to receive the input signal and generate an amplified main channel signal using a main amplifier operated in its non-linear region; an auxiliary channel adapted to apply the input signal to a model of the main amplifier to generate an auxiliary channel signal; and a summation node adapted to combine the amplified main channel signal and the auxiliary channel signal to generate the linearized amplified output signal, wherein the auxiliary channel further comprises: an auxiliary summation node adapted to generate an error signal based on a difference between the input signal and the output of the main amplifier model; and an auxiliary amplifier adapted to amplify the error signal to generate the auxiliary channel signal.
Claim 2
Dependent Claim
138 words
An amplifier circuit adapted to generate a linearized amplified output signal from an input signal, the amplifier circuit comprising: a main channel adapted to receive the input signal and generate an amplified main channel signal using a main amplifier operated in its non-linear region; an auxiliary channel adapted to apply the input signal to a model of the main amplifier to generate an auxiliary channel signal; and a summation node adapted to combine the amplified main channel signal and the auxiliary channel signal to generate the linearized amplified output signal, wherein the auxiliary channel further comprises: an auxiliary summation node adapted to generate an error signal based on a difference between the input signal and the output of the main amplifier model; and an auxiliary amplifier adapted to amplify the error signal to generate the auxiliary channel signal.
Claim 3
Dependent Claim
16 words
The invention of claim 1 , wherein the auxiliary amplifier is operated in its linear region.
Claim 4
Dependent Claim
24 words
The invention of claim 1 , wherein the power level of the auxiliary amplifier is less than the power level of the main amplifier.
Claim 5
Dependent Claim
27 words
The invention of claim 1 , wherein the amplified main channel signal is not applied directly to the main amplifier model in generating the auxiliary channel signal.
Claim 6
Dependent Claim
17 words
The invention of claim 1 , wherein the amplifier circuit is implemented without any high-power delay modules.
Claim 7
Dependent Claim
27 words
The invention of claim 1 , wherein the amplifier circuit is implemented without any delay module between the output of the main amplifier and the summation node.
Claim 8
Dependent Claim
34 words
The invention of claim 1 , further comprising a feed-back control channel adapted to generate one or more control signals for controlling operations of one or more components in the main and auxiliary channels.
Claim 9
Dependent Claim
27 words
The invention of claim 1 , wherein the main channel further comprises a pre-distorter adapted to pre-distort the input signal prior to application to the main amplifier.
Claim 10
Dependent Claim
62 words
The invention of claim 1 , wherein: the main channel further comprises a main equalizer adapted to equalize the main channel signal prior to application to the main amplifier; and the auxiliary channel further comprises an auxiliary equalizer adapted to equalize the error signal, wherein the auxiliary amplifier is adapted to amplify the equalized error signal to generate the auxiliary channel signal.
Claim 11
Dependent Claim
27 words
The invention of claim 9 , wherein the main channel further comprises a pre-distorter adapted to pre-distort the input signal prior to application to the main equalizer.
Claim 12
Dependent Claim
16 words
The invention of claim 9 , wherein the auxiliary amplifier is operated in its linear region.
Claim 13
Dependent Claim
24 words
The invention of claim 9 , wherein the power level of the auxiliary amplifier is less than the power level of the main amplifier.
Claim 14
Dependent Claim
25 words
The invention of claim 9 , wherein the main and auxiliary equalizers compensate for phase, amplitude, and delay differences between the main and auxiliary channels.
Claim 15
Dependent Claim
42 words
The invention of claim 9 , further comprising a feed-back control channel adapted to generate one or more control signals for controlling operations of one or more of the main equalizer, the main amplifier model, the auxiliary equalizer, and the auxiliary amplifier.
Claim 16
Dependent Claim
50 words
The invention of claim 14 , wherein the feed-back control channel comprises: a switch block adapted to select one or more signals for use in generating the control signals; and a control algorithm block adapted to generate the one or more control signals from the one or more selected signals.
Claim 17
Dependent Claim
68 words
The invention of claim 15 , wherein the switch block is adapted to receive and select one or more of (1) the signal input to the main amplifier, (2) the amplified main channel signal output from the main amplifier, (3) the signal input to the auxiliary amplifier, (4) the auxiliary channel signal output from the auxiliary amplifier, and (5) the linearized amplified output signal from the summation node.
Claim 18
Dependent Claim
26 words
The invention of claim 9 , wherein the main equalizer, the main amplifier model, and the auxiliary equalizer are adapted to operate in a digital domain.
Claim 19
Dependent Claim
90 words
The invention of claim 17 , wherein: the amplifier circuit further comprises an analog-to-digital converter (ADC) adapted to digitize an analog input signal for processing by the main and auxiliary channels; the main channel further comprises a main digital-to-analog converter (DAC) adapted to convert the output of the main equalizer to an analog domain prior to application to the main amplifier; and the auxiliary channel further comprises an auxiliary DAC adapted to convert the output of the auxiliary equalizer to the analog domain prior to application to the auxiliary amplifier.
Claim 20
Dependent Claim
99 words
The invention of claim 18 , wherein: the amplifier circuit further comprises an RF/IF (radio frequency to intermediate frequency) converter adapted to convert an analog RF input signal into an analog IF input signal prior to application to the ADC; the main channel further comprises a main IF/RF converter adapted to convert the output of the main DAC from IF to RF prior to application to the main amplifier; and the auxiliary channel further comprises an auxiliary IF/RF converter adapted to convert the output of the auxiliary DAC from IF to RF prior to application to the auxiliary amplifier.
Claim 21
Independent Claim
114 words
A method for generating a linearized amplified output signal from an input signal, the method comprising: generating an amplified main channel signal based on the input signal using a main amplifier operating in its non-linear region; generating an auxiliary channel signal based on the input signal using a model of the main amplifier; and combining the amplified main channel signal and the auxiliary channel signal to generate the linearized amplified output signal, wherein generating the auxiliary channel further comprises: generating an error signal based on a difference between the input signal and the output of the main amplifier model; and amplifying the error signal using an auxiliary amplifier to generate the auxiliary channel signal.
Claim 22
Independent Claim
114 words
A method for generating a linearized amplified output signal from an input signal, the method comprising: generating an amplified main channel signal based on the input signal using a main amplifier operating in its non-linear region; generating an auxiliary channel signal based on the input signal using a model of the main amplifier; and combining the amplified main channel signal and the auxiliary channel signal to generate the linearized amplified output signal, wherein generating the auxiliary channel further comprises: generating an error signal based on a difference between the input signal and the output of the main amplifier model; and amplifying the error signal using an auxiliary amplifier to generate the auxiliary channel signal.
Claim 23
Dependent Claim
16 words
The invention of claim 20 , wherein the auxiliary amplifier is operated in its linear region.
Claim 24
Dependent Claim
24 words
The invention of claim 20 , wherein the power level of the auxiliary amplifier is less than the power level of the main amplifier.
Claim 25
Dependent Claim
27 words
The invention of claim 20 , wherein the amplified main channel signal is not applied directly to the main amplifier model in generating the auxiliary channel signal.
Claim 26
Dependent Claim
16 words
The invention of claim 20 , wherein the method is implemented without any high-power delay modules.
Claim 27
Dependent Claim
38 words
The invention of claim 20 , wherein the method is implemented without any delay module between the output of the main amplifier and a summation node that combines the amplified main channel signal and the auxiliary channel signal.
Claim 28
Dependent Claim
28 words
The invention of claim 20 , further comprising generating one or more control signals for controlling operations of one or more components in the main and auxiliary channels.
Claim 29
Dependent Claim
25 words
The invention of claim 20 , wherein generating the amplified main channel signal comprises pre-distorting the input signal prior to application to the main amplifier.
Claim 30
Dependent Claim
56 words
The invention of claim 20 , wherein: generating the amplified main channel signal further comprises equalizing the main channel signal prior to application to the main amplifier; and generating the auxiliary channel signal further comprises equalizing the error signal, wherein the equalized error signal is amplified using the auxiliary amplifier to generate the auxiliary channel signal.
Claim 31
Dependent Claim
22 words
The invention of claim 28 , wherein generating the amplified main channel signals further comprises pre-distorting the input signal prior to equalizing.
Claim 32
Dependent Claim
16 words
The invention of claim 28 , wherein the auxiliary amplifier is operated in its linear region.
Claim 33
Dependent Claim
24 words
The invention of claim 28 , wherein the power level of the auxiliary amplifier is less than the power level of the main amplifier.
Claim 34
Dependent Claim
29 words
The invention of claim 28 , wherein equalizing the main channel signal and the error signal compensates for phase, amplitude, and delay differences between the main and auxiliary channels.
Claim 35
Dependent Claim
36 words
The invention of claim 28 , further comprising generating one or more control signals for controlling operations of one or more of a main equalizer, the main amplifier model, an auxiliary equalizer, and the auxiliary amplifier.
Claim 36
Dependent Claim
42 words
The invention of claim 33 , wherein generating the one or more control signals comprises: selecting one or more signals for use in generating the control signals; and generating the one or more control signals from the one or more selected signals.
Claim 37
Dependent Claim
81 words
The invention of claim 34 , wherein selecting the one or more signals comprises receiving and selecting one or more of (1) the signal input to the main amplifier, (2) the amplified main channel signal output from the main amplifier, (3) the signal input to the auxiliary amplifier, (4) the auxiliary channel signal output from the auxiliary amplifier, and (5) the linearized amplified output signal from a summation node that combines the amplified main channel signal and the auxiliary channel signal.
Claim 38
Dependent Claim
26 words
The invention of claim 28 , wherein a main equalizer, the main amplifier model, and an auxiliary equalizer are adapted to operate in a digital domain.
Claim 39
Dependent Claim
69 words
The invention of claim 36 , further comprising: digitizing, using an ADC, an analog input signal for processing by the main and auxiliary channels; converting, using a main DAC, the output of the main equalizer to an analog domain prior to application to the main amplifier; and converting, using an auxiliary DAC, the output of the auxiliary equalizer to the analog domain prior to application to the auxiliary amplifier.
Claim 40
Dependent Claim
63 words
The invention of claim 37 , further comprising: converting an analog RF input signal into an analog IF input signal prior to application to the ADC; converting the output of the main DAC from IF to RF prior to application to the main amplifier; and converting the output of the auxiliary DAC from IF to RF prior to application to the auxiliary amplifier.
Claim 41
Independent Claim
123 words
An apparatus for generating a linearized amplified output signal from an input signal, the apparatus comprising: means for generating an amplified main channel signal based on the input signal using a main amplifier operating in its non-linear region; means for generating an auxiliary channel signal based on the input signal using a model of the main amplifier; and means for combining the amplified main channel signal and the auxiliary channel signal to generate the linearized amplified output signal, wherein the means for generating the auxiliary channel signal comprises: means for generating an error signal based on a difference between the input signal and the output of the main amplifier model; and means for amplifying the error signal to generate the auxiliary channel signal.
Claim 42
Independent Claim
123 words
An apparatus for generating a linearized amplified output signal from an input signal, the apparatus comprising: means for generating an amplified main channel signal based on the input signal using a main amplifier operating in its non-linear region; means for generating an auxiliary channel signal based on the input signal using a model of the main amplifier; and means for combining the amplified main channel signal and the auxiliary channel signal to generate the linearized amplified output signal, wherein the means for generating the auxiliary channel signal comprises: means for generating an error signal based on a difference between the input signal and the output of the main amplifier model; and means for amplifying the error signal to generate the auxiliary channel signal.
Claim 43
Dependent Claim
111 words
An amplifier circuit adapted to generate a linearized amplified output signal from an input signal, the amplifier circuit comprising: a main channel adapted to receive the input signal and generate an amplified main channel signal using a main amplifier operated in its non-linear region; an auxiliary channel adapted to apply the input signal to a model of the main amplifier to generate an auxiliary channel signal; and a summation node adapted to combine the amplified main channel signal and the auxiliary channel signal to generate the linearized amplified output signal, wherein the amplified main channel signal is not applied directly to the main amplifier model in generating the auxiliary channel signal.
Claim 44
Dependent Claim
111 words
An amplifier circuit adapted to generate a linearized amplified output signal from an input signal, the amplifier circuit comprising: a main channel adapted to receive the input signal and generate an amplified main channel signal using a main amplifier operated in its non-linear region; an auxiliary channel adapted to apply the input signal to a model of the main amplifier to generate an auxiliary channel signal; and a summation node adapted to combine the amplified main channel signal and the auxiliary channel signal to generate the linearized amplified output signal, wherein the amplified main channel signal is not applied directly to the main amplifier model in generating the auxiliary channel signal.
Claim 45
Dependent Claim
116 words
An amplifier circuit adapted to generate a linearized amplified output signal from an input signal, the amplifier circuit comprising: a main channel adapted to receive the input signal and generate an amplified main channel signal using a main amplifier operated in its non-linear region; an auxiliary channel adapted to apply the input signal to a model of the main amplifier to generate an auxiliary channel signal; a summation node adapted to combine the amplified main channel signal and the auxiliary channel signal to generate the linearized amplified output signal; and a feed-back control channel adapted to generate one or more control signals for controlling operations of one or more components in the main and auxiliary channels.
Claim 46
Dependent Claim
116 words
An amplifier circuit adapted to generate a linearized amplified output signal from an input signal, the amplifier circuit comprising: a main channel adapted to receive the input signal and generate an amplified main channel signal using a main amplifier operated in its non-linear region; an auxiliary channel adapted to apply the input signal to a model of the main amplifier to generate an auxiliary channel signal; a summation node adapted to combine the amplified main channel signal and the auxiliary channel signal to generate the linearized amplified output signal; and a feed-back control channel adapted to generate one or more control signals for controlling operations of one or more components in the main and auxiliary channels.
Claim 47
Dependent Claim
106 words
An amplifier circuit adapted to generate a linearized amplified output signal from an input signal, the amplifier circuit comprising: a main channel adapted to receive the input signal and generate an amplified main channel signal using a main amplifier operated in its non-linear region; an auxiliary channel adapted to apply the input signal to a model of the main amplifier to generate an auxiliary channel signal, wherein the main amplifier model models distortion of the main amplifier without generating an amplified signal; and a summation node adapted to combine the amplified main channel signal and the auxiliary channel signal to generate the linearized amplified output signal.
Claim 48
Dependent Claim
106 words
An amplifier circuit adapted to generate a linearized amplified output signal from an input signal, the amplifier circuit comprising: a main channel adapted to receive the input signal and generate an amplified main channel signal using a main amplifier operated in its non-linear region; an auxiliary channel adapted to apply the input signal to a model of the main amplifier to generate an auxiliary channel signal, wherein the main amplifier model models distortion of the main amplifier without generating an amplified signal; and a summation node adapted to combine the amplified main channel signal and the auxiliary channel signal to generate the linearized amplified output signal.
Claim 49
Dependent Claim
109 words
An amplifier circuit adapted to generate a linearized amplified output signal from an input signal, the amplifier circuit comprising: a main channel adapted to receive the input signal and generate an analog amplified main channel signal using an analog main amplifier operated in its non-linear region; an auxiliary channel adapted to apply the input signal to a digital model of the analog main amplifier to generate an auxiliary channel signal, wherein the digital model models, in a digital domain, distortion of the analog main amplifier; and a summation node adapted to combine the amplified main channel signal and the auxiliary channel signal to generate the linearized amplified output signal.
Claim 50
Dependent Claim
109 words
An amplifier circuit adapted to generate a linearized amplified output signal from an input signal, the amplifier circuit comprising: a main channel adapted to receive the input signal and generate an analog amplified main channel signal using an analog main amplifier operated in its non-linear region; an auxiliary channel adapted to apply the input signal to a digital model of the analog main amplifier to generate an auxiliary channel signal, wherein the digital model models, in a digital domain, distortion of the analog main amplifier; and a summation node adapted to combine the amplified main channel signal and the auxiliary channel signal to generate the linearized amplified output signal.
Claim 51
Dependent Claim
24 words
The invention of claim 43 , wherein the digital model models the distortion of the analog main amplifier without generating an amplified analog signal.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2007-07-20 | 2008-01-19 | 2008-07-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2011-07-20 | 2012-01-19 | 2012-07-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2015-07-20 | 2016-01-19 | 2016-07-20 | $7700.00 | Window Closed / Lapsed |