JP2002237727A - Feedforward amplifier, communication apparatus, feed forward amplification method, program and medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem that it is impossible to efficiently suppress distortion components in a conventional feedforward amplifier. SOLUTION: In this feedforward amplifier, a vector adjuster 12 is adjusted to suppress only distortion components within a predetermined frequency range in a suppressed-frequency range where distortion components to be suppressed occur (1), or that is adjusted so that the suppression of the distortion components within the predetermined frequency range is larger than the suppression of the distortion components within the predetermined frequency ranges which are in the suppress-frequency range but are other ones than the predetermined frequency range (2). A predistortion circuit 6 is adjusted to perform at least suppression of the distortion components within the frequency ranges other than the predetermined frequency range.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a feedforward amplifier, a communication device, a feedforward amplification method, a program, and a medium used in, for example, a base station device of a mobile communication device.

[0002]

2. Description of the Related Art In recent years, a base station apparatus of a mobile communication apparatus has used a high-output linear power amplifier which compensates for distortion by a feedforward system.

First, the configuration of a conventional feedforward amplifier will be described with reference to FIG. 12, which is a configuration diagram of a conventional feedforward amplifier.

In FIG. 12, 1 is an input terminal, 2 is an output terminal, 3 and 9 are power dividers, 4 and 10 are power combiners,
Reference numerals 5 and 12 are vector adjusters, 7 is a main amplifier, 8 and 11 are delay circuits, and 13 is an auxiliary amplifier. Also, symbols a to k attached to the power distributors 3 and 9 and the power combiners 4 and 10,
m represents each port.

Next, the operation of the conventional feedforward amplifier configured as described above will be described.

First, an input signal containing a plurality of carrier frequency components input from an input terminal 1 is split into two by a power splitter 3 and output from ports b and c, respectively.

The signal output from the port b is amplified by the main amplifier 7 through the vector adjuster 5 and input to the port j of the power combiner 4 through the power distributor 9 and the delay circuit 11. At this time, due to the nonlinearity of the main amplifier 7,
A signal containing a distortion component due to intermodulation in addition to the carrier frequency component is input. Also, a part of the output signal of the main amplifier 7 is taken out from the port f of the power divider 9 and inputted to the port h of the power combiner 10.

On the other hand, the signal output from port c is input to port g of power combiner 10 through delay circuit 8.

Here, by adjusting the vector adjuster 5 and the delay circuit 8 so that the carrier frequency components of the signals input to the ports g and h are equal in amplitude and opposite in phase, the carrier frequency from the port i is adjusted. A signal of only the distortion component whose components have been canceled is output.

Next, the signal output from the port i is amplified by the auxiliary amplifier 13 through the vector adjuster 12,
It is input to port k of power combiner 4.

Here, the port of the power combiner 4 is adjusted by adjusting the vector adjuster 12 and the delay circuit 11 so that the distortion components of the signals input to the ports j and k have the same amplitude and opposite phases. m to the output terminal 2 outputs a signal of only the carrier frequency component in which the distortion component has been canceled.

Note that there is a predistortion method (predistortion method) as another distortion compensation method different from the distortion compensation method described above.

The configuration of the pre-distortion circuit will be described with reference to FIG. 13, which is a configuration diagram of the pre-distortion circuit.

In FIG. 13, reference numeral 61 denotes a power distributor;
Is a power divider, 63 is a delay circuit, 69 is a vector adjuster, and 72 is a distortion generating circuit. The power distributor 61, the power combiner 62, the delay circuit 63, the vector adjuster 69, and the distortion generating circuit 72 constitute the predistortion circuit 6. The symbol n attached to the power combiner 62 represents a port.

Next, the operation of the pre-distortion circuit configured as described above will be described with reference to FIG.

The pre-distortion method uses the main amplifier 7
In this method, distortion is suppressed by injecting a signal having the same frequency component as that of the distortion component generated in the main amplifier 7 into an appropriate amplitude / phase relationship.

An input signal containing a plurality of carrier frequency components input from an input terminal (the left terminal in FIG. 13) is split into two by a power splitter 61.

One of the two output signals is input to a power combiner 62 through a delay circuit 63. The other of the two output signals is input to a distortion generation circuit 72,
A signal having the same frequency component as the distortion component generated in the main amplifier 7 is output. The signal output from the distortion generating circuit 72 is input to the power combiner 62 through the vector adjuster 69, and is combined with the output signal from the delay circuit 63. At this time, the vector adjuster 69 is adjusted so that the input signal has an appropriate amplitude / phase relationship.

The signal synthesized by power combiner 62 is output from port n and input to main amplifier 7.

[0020]

However, FIG.
In the feedforward amplifier of the above, as the carrier band becomes wider, the condition of the vector adjuster 12 for maximally suppressing the distortion component generated on the higher frequency side and the distortion component generated on the lower frequency side of the carrier band is shifted. . That is, if the vector adjuster 12 is adjusted to suppress the distortion component on the high frequency side to the maximum, the distortion component on the low frequency side is not sufficiently suppressed, and vice versa. So far, so that the distortion component on the high frequency side and the distortion component on the low frequency side are at the same level,
The vector adjuster 12 was adjusted.

Also, in the pre-distortion circuit of FIG. 13, as the carrier band becomes wider,
It becomes difficult to simultaneously suppress a distortion component generated on the higher frequency side and a distortion component generated on the lower frequency side than the carrier band. For this reason, the high frequency side distortion component and the low frequency side distortion component are suppressed so that they are at the same level. As a result, the distortion component can be suppressed only by about several dB.

In the feedforward amplifier using both the predistortion method and the feedforward method, the suppression is performed such that the high-frequency distortion component and the low-frequency distortion component are at the same level. Main amplifier 7
When the distortion component generated in step (1) is unbalanced between the high band side and the low band side of the carrier band, distortion suppression has not been efficiently performed until now for the above-described reason.

An object of the present invention is to provide a feedforward amplifier, a communication device, a feedforward amplification method, a program, and a medium that can efficiently suppress distortion components in consideration of the above-described conventional problems. And

[0024]

Means for Solving the Problems The first invention (claim 1)
), A first power divider for dividing an input signal into two, a first vector adjuster for adjusting the amplitude and phase of one output signal of the first power divider, and the first power divider. A predistortion compensation circuit connected to the vector adjuster, a main amplifier for amplifying an output signal of the predistortion compensation circuit, and a second power divider for dividing the output signal of the main amplifier into two, A first delay circuit for delaying the other output signal of the first power divider; and a distortion detection for combining one output signal of the second power divider with the output signal of the first delay circuit. Power combiner, a second delay circuit for delaying the other output signal of the second power divider, and a second vector adjuster for adjusting the amplitude and phase of the output signal of the distortion detection combiner An auxiliary amplifier for amplifying an output signal of the second vector adjuster; A distortion canceling power combiner for combining an output signal of the second delay circuit and an output signal of the auxiliary amplifier, wherein the second vector adjuster includes: (1) a distortion component to be suppressed; In order to suppress only the distortion component occurring in a predetermined frequency range in the generated suppression target frequency range, or (2) suppressing the distortion component occurring in the predetermined frequency range is performed in the suppression target frequency range. Of which
Adjusted to be greater than suppression of distortion components occurring in a frequency range other than the predetermined frequency range, the predistortion compensation circuit suppresses distortion components occurring in a frequency range other than the predetermined frequency range. At least a feedforward amplifier that is tuned to do so.

According to a second aspect of the present invention (corresponding to claim 2), the predetermined frequency range is the entire high-frequency or low-frequency side distortion signal band generated by the main amplifier. Is a feedforward amplifier.

According to a third aspect of the present invention (corresponding to claim 3), the predistortion compensation circuit is provided between the first power distributor and the first vector adjuster. Is a feedforward amplifier of the present invention.

According to a fourth aspect of the present invention (corresponding to claim 4), at least one pilot signal oscillator, an output signal of the pilot signal oscillator and an output signal of the predistortion compensation circuit are combined, and A first power combiner for outputting to the amplifier and a third power divider for dividing an output signal of the distortion detecting power combiner into two and inputting one of the output signals to the second vector adjuster; A fourth power splitter for splitting the other output signal of the third power splitter into two,
A band-pass filter connected to one output terminal of the power splitter, a distortion level detection circuit for detecting a signal level of an output signal of the band-pass filter, and a second output signal of the fourth power splitter. A carrier level detection circuit for detecting a signal level, a fifth power divider for dividing an output signal of the distortion removing power combiner into two, and detecting a signal level of one output signal of the fifth power divider. And (1) the predistortion compensating circuit based on the signal level detected by the distortion level detecting circuit, and (2) the first vector based on the signal level detected by the carrier level detecting circuit. (3) The second adjuster controls the second level based on the signal level detected by the pilot level detection circuit.
And a control means for automatically adjusting each of the vector adjusters, and the other output signal of the fifth power divider is a feedforward amplifier of the first present invention supplied to a subsequent stage.

A fifth aspect of the present invention (corresponding to claim 5) is a third aspect in which the output signal of the distortion detection power combiner is divided into two, and one output signal is input to the second vector adjuster. A power divider and the other output signal of the third power divider to 2
A fourth power divider for distribution, a band-pass filter connected to one output terminal of the fourth power divider, an output signal of the band-pass filter, and another output of the fourth power divider. A switch circuit for selecting and switching a signal according to a control signal from the control means; and a signal of the selected signal among an output signal of the band-pass filter and the other output signal of the fourth power divider. (1) When the output signal of the band-pass filter is selected by the signal level detection circuit for detecting the level and the signal level detected by the signal level detection circuit, the predistortion compensation circuit includes: (2) When the other output signal of the fourth power divider is selected, the feeder according to the first aspect of the present invention includes control means for automatically adjusting each of the first vector adjusters. It is the word amplifier.

A sixth aspect of the present invention (corresponding to claim 6) is that the control means stops the operation of the auxiliary amplifier or the function of the predistortion circuit based on a predetermined condition. 3 is a feedforward amplifier of the invention.

A seventh aspect of the present invention (corresponding to claim 7) includes input signal level detection means for detecting a signal level of the input signal, and operates the auxiliary amplifier or the pre-amplifier based on the predetermined condition. Stopping the function of the distortion compensation circuit means that the control means stops the operation of the auxiliary amplifier when the signal level of the detected input signal is equal to or less than a predetermined value. It is a feedforward amplifier.

An eighth invention (corresponding to claim 8) comprises input signal level detecting means for detecting a signal level of the input signal, and operates the auxiliary amplifier or the pre-amplifier based on the predetermined condition. Stopping the function of the distortion compensation circuit means that the control unit stops the function of the pre-distortion compensation circuit when the signal level of the detected input signal is equal to or less than a predetermined value. 5 is a feedforward amplifier of the present invention.

A ninth aspect of the present invention (corresponding to claim 9) includes input signal level detecting means for detecting a signal level of the input signal, and operates the auxiliary amplifier or the pre-amplifier based on the predetermined condition. Stopping the function of the distortion compensating circuit means that the control means (1) sets that the signal level of the detected input signal is equal to or less than a first predetermined value and smaller than the first predetermined value. If the value is larger than a second predetermined value, the function of the predistortion compensation circuit is stopped,
(2) The feedforward amplifier according to the sixth aspect of the present invention, wherein the operation of the auxiliary amplifier is stopped when the signal level of the input signal is equal to or less than the second predetermined value.

A tenth aspect of the present invention (corresponding to claim 10) is a transmission line arranged in parallel with the predistortion compensating circuit, an input side of the predistortion compensating circuit and the transmission line, and A first and a second switch circuit for switching between the predistortion compensation circuit side and the transmission line side, which are respectively disposed on the output side of the predistortion compensation circuit and the transmission line; Stopping the function of the distortion compensating circuit means connecting the first and second switch circuits to the transmission line side in the feedforward amplifier according to the sixth aspect of the present invention.

The eleventh present invention (corresponding to claim 11) provides:
The input signal level detecting means is a feedforward amplifier according to any one of the seventh to ninth aspects of the present invention provided in a signal path including an input signal component.

The twelfth invention (corresponding to claim 12) provides:
A pre-distortion compensating circuit comprising: a sixth power splitter for splitting a signal into two; a distortion generating circuit for inputting one output signal of the sixth power splitter to generate a distortion; A third vector adjuster for adjusting the amplitude and phase of the output signal of the third power supply, a third delay circuit for delaying the other output signal of the sixth power divider, and an output signal of the third vector adjuster And a second signal combining the output signal of the third delay circuit
And a power combiner according to any one of the first to tenth aspects of the present invention.

A thirteenth aspect of the present invention (corresponding to claim 13) is:
The distortion generating circuit includes: a seventh power divider that divides a signal into two; a fourth vector adjuster that adjusts an amplitude and a phase of one output signal of the seventh power divider; A distortion generating power amplifier for amplifying the output signal of the vector adjuster, a fourth delay circuit for delaying the other output signal of the seventh power divider, an output signal of the distortion generating power amplifier, A twelfth feedforward amplifier according to the present invention, comprising a third power combiner that combines the output of the fourth delay circuit.

The fourteenth invention (corresponding to claim 14) is:
The automatic adjustment of the predistortion compensating circuit based on the signal level detected by the distortion level detecting circuit is to adjust the amplitude and phase of the third vector adjuster. It is a forward amplifier.

The fifteenth invention (corresponding to claim 15) is:
Stopping the function of the predistortion compensating circuit means that the output signal from the distortion generating circuit is not input to the second power combiner in the twelfth feedforward amplifier of the present invention.

A sixteenth aspect of the present invention (corresponding to claim 16) is:
The distortion generating circuit is a twelfth feedforward amplifier according to the present invention, which includes only a distortion generating power amplifier for amplifying an input signal.

The seventeenth invention (corresponding to claim 17) is:
The third delay circuit is a twelfth feedforward amplifier of the present invention configured using all or a part of the first delay circuit.

The eighteenth invention (corresponding to claim 18) is:
The fourth delay circuit is a thirteenth aspect of the present invention, wherein the fourth delay circuit is configured using all or a part of the first delay circuit.

The nineteenth invention (corresponding to claim 19) is:
The distortion generating power amplifier is a thirteenth aspect of the present invention, which comprises a nonlinear device.

The twentieth invention (corresponding to claim 20) is:
The distortion component generated in the predetermined frequency range is the feedforward amplifier according to the first aspect of the present invention, which is larger than the distortion component generated in a frequency range other than the predetermined frequency range.

The twenty-first invention (corresponding to claim 21)
The adjustment is performed such that, of the distortion components to be suppressed, a distortion component generated in a predetermined frequency range is larger than a distortion component generated in a frequency range other than the predetermined frequency range. Item 2. A feedforward amplifier according to Item 1.

Twenty-second invention (corresponding to claim 22)
A pilot signal oscillator that can be adjusted so that an oscillation frequency falls within the vicinity of the predetermined frequency range, an output signal of the pilot signal oscillator and an output signal of the predistortion compensation circuit are combined, and the main amplifier And a first power combiner for outputting the output signal of the distortion detecting power combiner.
A third power splitter for splitting and inputting one output signal to the second vector adjuster, a fourth power splitter for splitting the other output signal of the third power splitter into three, A low-pass distortion signal band-pass filter connected to a first output terminal of the fourth power divider; and a low-pass distortion level for detecting a signal level of an output signal of the low-pass distortion signal band-pass filter. A detection circuit, a high-band distortion signal band-pass filter connected to a second output terminal of the fourth power divider, and a high-frequency signal for detecting a signal level of an output signal of the high-band distortion signal band-pass filter. A band-side distortion level detecting circuit, a carrier level detecting circuit for detecting a signal level of a third output signal of the fourth power divider, and a fifth for dividing an output signal of the distortion removing power combiner into two. A power divider and one output of the fifth power divider A pilot level detection circuit for detecting a signal level of the signal, and (1) the predistortion based on the signal level detected by the low-frequency distortion level detection circuit and the signal level detected by the high-frequency distortion level detection circuit. The compensation circuit and the pilot signal oscillator are controlled by the signal level detected by the carrier level detection circuit.
And (3) control means for automatically adjusting each of the second vector adjusters based on the signal level detected by the pilot level detection circuit, and the other of the fifth power splitters. The output signal is the twenty-first feedforward amplifier of the present invention supplied to the subsequent stage.

Twenty-third invention (corresponding to claim 23)
The automatic adjustment of the predistortion compensating circuit and the pilot signal oscillator includes the steps of: (a) setting the signal level detected by the low-frequency distortion level detection circuit to be lower than the signal level detected by the high-frequency distortion level detection circuit If the signal level detected by the high-frequency side distortion level detection circuit is higher than the low-frequency side, the predetermined frequency range is set to be the frequency range corresponding to the low-frequency side. In the case where the signal level is higher than the signal level detected by the distortion level detection circuit, the feedforward amplifier according to the twenty-second aspect of the present invention is performed such that the predetermined frequency range is a frequency range corresponding to the high frequency side. is there.

Twenty-fourth invention (corresponding to claim 24)
A first power divider for dividing an input signal into two, a first vector adjuster for adjusting an amplitude and a phase of one output signal of the first power divider, and the first vector adjuster Main amplifier for amplifying the output signal of the first amplifier, a second power divider for dividing the output signal of the main amplifier into two, and a first delay circuit for delaying the other output signal of the first power divider A distortion detection power combiner for combining one output signal of the second power divider and an output signal of the first delay circuit; and delaying the other output signal of the second power divider. A second delay circuit, a second vector adjuster for adjusting an amplitude and a phase of an output signal of the distortion detection combiner, an auxiliary amplifier for amplifying an output signal of the second vector adjuster, The output signal of the second delay circuit and the output signal of the auxiliary amplifier A power combiner for removing distortion, wherein the second vector adjuster includes: (1) a distortion component generated in a predetermined frequency range within a frequency range to be suppressed in which a distortion component to be suppressed is generated; Or (2) the suppression of the distortion component occurring in the predetermined frequency range is performed by suppressing the distortion component occurring in the frequency range other than the predetermined frequency range in the suppression target frequency range. This is a feedforward amplifier that is adjusted to be larger than suppression.

Twenty-fifth invention (corresponding to claim 25)
Is a communication device using the feedforward amplifier according to any one of the first to twenty-fourth inventions.

Twenty-sixth aspect of the present invention (corresponding to claim 26)
Distributing the input signal into two using a first power divider, and using the first vector adjuster to
Adjusting the amplitude and phase of one of the output signals of the power divider, and amplifying the output signal of the predistortion compensation circuit connected to the first vector adjuster using a main amplifier; Splitting the output signal of the main amplifier into two using a second power splitter, delaying the other output signal of the first power splitter using a first delay circuit; Combining one output signal of the second power divider with the output signal of the first delay circuit by using a distortion detection power combiner; and Delaying the other output signal of the second power divider, adjusting the amplitude and phase of the output signal of the distortion detecting combiner using a second vector adjuster, and using an auxiliary amplifier. And the output of the second vector adjuster Amplifying the output signal of the second delay circuit and the output signal of the auxiliary amplifier using a power combiner for removing distortion. 1) Suppression of only a distortion component occurring in a predetermined frequency range in a suppression target frequency range in which a distortion component to be suppressed occurs, or (2) Distortion occurring in the predetermined frequency range Adjusting the suppression of the component to be greater than the suppression of the distortion component occurring in a frequency range other than the predetermined frequency range in the frequency range to be suppressed; and And adjusting so as to at least suppress distortion components occurring in a frequency range other than the above frequency range.

The 27th invention (corresponding to claim 27)
Distributing the input signal into two using a first power divider, and using the first vector adjuster to
Adjusting the amplitude and phase of one output signal of the power divider, amplifying the output signal of the first vector adjuster using a main amplifier, and using a second power divider. Distributing the output signal of the main amplifier into two, delaying the other output signal of the first power divider using a first delay circuit, and using a power detector for distortion detection. Combining one output signal of the second power divider with the output signal of the first delay circuit, and using the second delay circuit to output the other output signal of the second power divider. Delaying the signal;
Adjusting the amplitude and the phase of the output signal of the distortion detecting combiner using the vector adjuster; amplifying the output signal of the second vector adjuster using an auxiliary amplifier; Synthesizing the output signal of the second delay circuit and the output signal of the auxiliary amplifier using a power combiner for elimination; and
(1) Suppression of only a distortion component occurring in a predetermined frequency range within a suppression target frequency range in which a distortion component to be suppressed occurs, or (2) Generation of a distortion component in the predetermined frequency range. And adjusting the suppression of the distortion component so as to be greater than the suppression of the distortion component occurring in a frequency range other than the predetermined frequency range in the suppression target frequency range.

The twenty-eighth invention (corresponding to claim 28)
Is a step of dividing an input signal into two using a first power divider in the feedforward amplification method according to the twenty-sixth aspect of the present invention, and the first vector adjuster using a first vector adjuster.
Adjusting the amplitude and phase of one of the output signals of the power divider, and amplifying the output signal of the predistortion compensation circuit connected to the first vector adjuster using a main amplifier; Splitting the output signal of the main amplifier into two using a second power splitter, delaying the other output signal of the first power splitter using a first delay circuit; Combining one output signal of the second power divider with the output signal of the first delay circuit by using a distortion detection power combiner; and Delaying the other output signal of the second power divider, adjusting the amplitude and phase of the output signal of the distortion detecting combiner using a second vector adjuster, and using an auxiliary amplifier. And the output of the second vector adjuster Amplifying the output signal of the second delay circuit and the output signal of the auxiliary amplifier using a power combiner for removing distortion. 1) Suppression of only a distortion component occurring in a predetermined frequency range in a suppression target frequency range in which a distortion component to be suppressed occurs, or (2) Distortion occurring in the predetermined frequency range Adjusting the suppression of the component to be greater than the suppression of the distortion component occurring in a frequency range other than the predetermined frequency range in the frequency range to be suppressed; and This is a program for causing a computer to execute all or a part of the step of adjusting so as to at least suppress distortion components occurring in a frequency range other than the above frequency range.

The twenty-ninth invention (corresponding to claim 29)
Is a step of dividing an input signal into two using a first power divider in the feedforward amplification method according to the twenty-sixth aspect of the present invention, and the first vector adjuster using a first vector adjuster.
Adjusting the amplitude and phase of one of the output signals of the power divider, and amplifying the output signal of the predistortion compensation circuit connected to the first vector adjuster using a main amplifier; Splitting the output signal of the main amplifier into two using a second power splitter, delaying the other output signal of the first power splitter using a first delay circuit; Combining one output signal of the second power divider with the output signal of the first delay circuit by using a distortion detection power combiner; and Delaying the other output signal of the second power divider, adjusting the amplitude and phase of the output signal of the distortion detecting combiner using a second vector adjuster, and using an auxiliary amplifier. And the output of the second vector adjuster Amplifying the output signal of the second delay circuit and the output signal of the auxiliary amplifier using a power combiner for removing distortion. 1) Suppression of only a distortion component occurring in a predetermined frequency range in a suppression target frequency range in which a distortion component to be suppressed occurs, or (2) Distortion occurring in the predetermined frequency range Adjusting the suppression of the component to be greater than the suppression of the distortion component occurring in a frequency range other than the predetermined frequency range in the frequency range to be suppressed; and And a step of adjusting so that at least suppression of distortion components occurring in a frequency range other than the frequency range is performed by a medium carrying a program for causing a computer to execute all or part of the step. It, is a medium that can be processed by a computer.

The thirtieth invention (corresponding to claim 30) is:
A step of dividing an input signal into two using a first power divider in the feed-forward amplification method according to the twenty-seventh aspect of the present invention; and the first power divider using a first vector adjuster. Adjusting the amplitude and phase of one of the output signals, amplifying the output signal of the first vector adjuster using a main amplifier, and adjusting the main amplifier using a second power divider. Dividing the output signal into two, using a first delay circuit to delay the other output signal of the first power divider, and using a distortion detection power combiner to Combining one output signal of the first power divider with the output signal of the first delay circuit, and using the second delay circuit to delay the other output signal of the second power divider. Use steps and a second vector adjuster Adjusting the amplitude and phase of the output signal of the distortion detecting combiner using the auxiliary amplifier, amplifying the output signal of the second vector adjuster using an auxiliary amplifier, and using the distortion removing power combiner. Combining the output signal of the second delay circuit and the output signal of the auxiliary amplifier, and setting the second vector adjuster to (1)
Among the suppression target frequency ranges in which the distortion components to be suppressed occur, only the distortion components occurring in a predetermined frequency range are suppressed, or (2) the distortion components occurring in the predetermined frequency range are suppressed. A program for causing a computer to execute all or part of the step of adjusting the suppression so that the suppression is greater than the suppression of distortion components occurring in a frequency range other than the predetermined frequency range in the suppression target frequency range. It is.

The thirty-first invention (corresponding to claim 31)
Is a step of dividing an input signal into two using a first power divider in the feedforward amplification method according to the twenty-seventh aspect of the present invention, and the first vector adjuster using a first vector adjuster.
Adjusting the amplitude and phase of one output signal of the power divider, amplifying the output signal of the first vector adjuster using a main amplifier, and using a second power divider. Distributing the output signal of the main amplifier into two, delaying the other output signal of the first power divider using a first delay circuit, and using a power detector for distortion detection. Combining one output signal of the second power divider with the output signal of the first delay circuit, and using the second delay circuit to output the other output signal of the second power divider. Delaying the signal;
Adjusting the amplitude and the phase of the output signal of the distortion detecting combiner using the vector adjuster; amplifying the output signal of the second vector adjuster using an auxiliary amplifier; Synthesizing the output signal of the second delay circuit and the output signal of the auxiliary amplifier using a power combiner for elimination; and
(1) Suppression of only a distortion component occurring in a predetermined frequency range within a suppression target frequency range in which a distortion component to be suppressed occurs, or (2) Generation of a distortion component in the predetermined frequency range. Making the computer execute all or part of the step of adjusting the suppression of the distortion component so as to be greater than the suppression of the distortion component occurring in a frequency range other than the predetermined frequency range in the suppression target frequency range. And a medium that can be processed by a computer.

[0055]

Embodiments of the present invention will be described below with reference to the drawings. It should be noted that the feature of the present invention is that one of the distortion components generated on the high band side and the low band side of the carrier band is mainly subjected to the distortion suppression by the feedforward method, and the deterioration of the amount of distortion suppression on the opposite side is thereby reduced. The point is that the minute is compensated by the pre-distortion method.

(Embodiment 1) First, the configuration of the feedforward amplifier according to the present embodiment will be described with reference to FIG. 1, which is a configuration diagram of the feedforward amplifier according to the first embodiment.

In FIG. 1, 1 is an input terminal, 2 is an output terminal, 3 and 9 are power dividers, 4 and 10 are power combiners, 5,
12 is a vector adjuster, 6 is a predistortion circuit (also referred to as a predistortion compensation circuit), 7 is a main amplifier, 8, 11
Is a delay circuit, and 13 is an auxiliary amplifier. The symbols a to k, m, and n attached to the power distributors 3, 9, the power combiners 4, 10, and the predistortion circuit 6 represent each port. Here, the same reference numerals are given to the same means as in the conventional case described above.

Note that the power divider 3 corresponds to the first power divider of the present invention, the vector adjuster 5 corresponds to the first vector adjuster of the present invention, and the pre-distortion circuit 6 is provided before the present invention. The main amplifier 7 corresponds to the main amplifier of the present invention, the power divider 9 corresponds to the second power divider of the present invention, and the delay circuit 8 corresponds to the first delay of the present invention. The power combiner 10 corresponds to the power combiner for distortion detection of the present invention, the delay circuit 11 corresponds to the second delay circuit of the present invention, and the vector adjuster 12 corresponds to the second delay circuit of the present invention. The auxiliary amplifier 13 corresponds to the auxiliary amplifier of the present invention, and the power combiner 4 corresponds to the distortion removing power combiner of the present invention.

Next, the operation of the feedforward amplifier according to the present embodiment will be described. Note that while describing the operation of the feedforward amplifier of the present embodiment, an embodiment of the feedforward amplification method of the present invention will be described (the same applies hereinafter).

An input signal containing a plurality of carrier frequency components input from input terminal 1 is input to port a of power distributor 3.

The signal input to the port a of the power distributor 3 is split into two and output from the ports b and c, respectively.

The signal output from the port b is amplified by the main amplifier 7 through the vector adjuster 5 and the predistortion circuit 6. At this time, a distortion component due to intermodulation occurs in addition to the carrier frequency component due to the non-linearity of the main amplifier 7, but as described later in detail, a part of the distortion component has the pre-distortion circuit 6 inserted therein. The output is suppressed.

The output signal of the main amplifier 7 is input to the port j of the power combiner 4 through the power divider 9 and the delay circuit 11, and a part of the output signal of the main amplifier 7 is And is input to port h of power combiner 10.

On the other hand, the signal output from port c is input to port g of power combiner 10 through delay circuit 8. Here, the carrier frequency components from the port i are adjusted by adjusting the vector adjuster 5 and the delay circuit 8 such that the carrier frequency components of the signals input to the port g and the port h are equal in amplitude and opposite in phase. Is output as a signal of only the distortion component in which is canceled. Then, the signal output from the port i is amplified by the auxiliary amplifier 13 through the vector adjuster 12 and input to the port k of the power combiner 4.

Here, by adjusting the vector adjuster 12 and the delay circuit 11 so that the distortion components of the signals input to the ports j and k have equal amplitudes and opposite phases, the ports of the power combiner 4 are adjusted. m to the output terminal 2 outputs a signal of only the carrier frequency component from which the distortion component has been canceled.

Next, one of the distortion components generated on the high band side and the low band side of the carrier band is mainly subjected to the distortion suppression by the feedforward method, and the deterioration amount of the distortion suppression amount on the opposite side due to it is determined. Regarding the feature of the present invention of compensating by the pre-distortion method, FIGS.
This will be described in detail with reference to FIG. Note that FIG.
2A is an explanatory diagram of a frequency spectrum of a signal at a port a, FIG. 2B is an explanatory diagram of a frequency spectrum of a signal at a port n, and FIG. 2C is a diagram of a frequency spectrum of a signal at a port d. FIG.
FIG. 2D is an explanatory diagram of the frequency spectrum of the signal at the port i, and FIG. 2E is an explanatory diagram of the frequency spectrum of the signal at the port m. Here, FIG.
In (a) to (e), illustration is made such that the carrier level is unitized.

For example, it is assumed that the distortion level generated in the higher band side than the carrier band generated in the main amplifier 7 is higher than the distortion level generated in the lower band side. When the vector adjuster 12 is adjusted so as to mainly suppress the distortion component on the high frequency side having a high distortion level by the feedforward method, the distortion suppression amount on the low frequency side deteriorates. Therefore, the pre-distortion circuit 6 suppresses a part of the distortion component on the low frequency side to compensate for this deterioration.

More specifically, for the signal input from the port a (see FIG. 2A), an injection distortion for suppressing a part of the low-frequency side distortion component by the pre-distortion circuit 6 is used. To obtain a signal output from the port n (see FIG. 2B). By this distortion suppression, the signal amplified by the main amplifier 7 and input to the port d (FIG. 2)
(C) suppresses the distortion level occurring on the lower side of the carrier band, and the signal output from the port i as a signal having only the distortion component (see FIG. 2 (d)) is also lower than the carrier band. The side has been oppressed. Therefore, the signal output from the port m (see FIG. 2E) is adjusted by adjusting the vector adjuster 12 so that the distortion level generated on the higher frequency side than the carrier band is more emphasized. Distortion levels generated on the low band side and the high band side from the band are both suppressed, and the signal becomes substantially only a carrier frequency component.

As described above, by employing the configuration shown in FIG. 1, one of the distortion components generated on the high band side and the low band side of the carrier band is mainly subjected to the distortion suppression by the feedforward method, and the accompanying distortion is thereby suppressed. If the degradation of the opposite side distortion suppression amount is compensated for by the predistortion method, the distortion compensation range in the predistortion method is narrowed, and the distortion component can be suppressed efficiently, and as a result, the distortion suppression amount can be improved.

(Embodiment 2) Next, Embodiment 2
FIG. 3 is a configuration diagram of the feedforward amplifier in FIG.
The configuration of the feedforward amplifier according to the present embodiment will be described with reference to FIG.

In FIG. 3, 61, 64, 83, 84,
88 is a power divider, 62, 65 and 82 are power combiners, 6
3, 66 are delay circuits, 67, 69 are vector adjusters, 6
Reference numeral 8 denotes a power amplifier for generating distortion, 81 denotes a pilot signal oscillator, 85 denotes a bandpass filter, 86 denotes a distortion level detection circuit, 87 denotes a carrier level detection circuit, 89 denotes a pilot level detection circuit, and 90 denotes a control circuit. Power distributor 6
4, power combiner 65, delay circuit 66, vector adjuster 6
7 and a distortion generating power amplifier 68 constitute a distortion generating circuit 72. Note that the power distributor 61, the power combiner 62,
Delay circuit 63, vector adjuster 69 and distortion generating circuit 7
2 constitutes a pre-distortion circuit 6A.

Note that the pilot signal oscillator 81 corresponds to the pilot signal oscillator of the present invention, the power combiner 82 corresponds to the first power combiner of the present invention, and the power divider 83 corresponds to the third power combiner of the present invention. The power divider 84 corresponds to the fourth power divider of the present invention, and corresponds to the band-pass filter 8.
5 corresponds to the band pass filter of the present invention, the distortion level detecting circuit 86 corresponds to the distortion level detecting circuit of the present invention, the carrier level detecting circuit 87 corresponds to the carrier level detecting circuit of the present invention, and the power divider 88 Corresponds to the fifth power divider of the present invention, the pilot level detecting circuit 89 corresponds to the pilot level detecting circuit of the present invention, and the control circuit 90 corresponds to the control means of the present invention.

The feedforward amplifier of the present embodiment always maintains the optimum suppression state even if the characteristics of the main amplifier 7 and the auxiliary amplifier 13 change due to aging and changes in the surrounding environment during operation. It is a feedforward amplifier that performs automatic adjustment.

Next, the operation of the feedforward amplifier according to the present embodiment will be described.

The principle of operation of the feedforward amplifier according to the present embodiment is the same as the principle of operation of the feedforward amplifier according to the first embodiment described above. Therefore, a detailed description thereof is omitted here. An important pre-distortion circuit 6A in the feedforward amplifier will be described.

The input signal containing a plurality of carrier frequency components output from the vector adjuster 5 is
Is divided into two.

One of the two output signals is input to the power combiner 62 through the delay circuit 63.

The other output signal that has been split into two is further split into two by a power splitter 64, and one output signal is amplified by a distortion generating power amplifier 68 through a vector adjuster 67 and input to a power combiner 65. Is done. The other output signal split into two by the power splitter 64 is supplied to the delay circuit 6.
6 and is input to a power combiner 65 and combined with an output signal from a distortion generating power amplifier 68. Here, by adjusting the vector adjuster 67 and the delay circuit 66 so that the carrier frequency components of both signals have the same amplitude and opposite phases, the carrier frequency components are canceled from the power combiner 65, and at least the pre-distortion is performed. The circuit 6A outputs a signal including a distortion component in a frequency band for which distortion compensation is performed.

The signal output from the power combiner 65 is input to the power combiner 62 through the vector adjuster 69.
The output signal from the delay circuit 63 is combined with the output signal. At this time,
The vector adjuster 69 is adjusted so that the distortion component of the main amplifier 7 generated in the frequency band for performing distortion compensation is suppressed to the maximum.

Next, a description will be given of a method of automatically adjusting the feedforward amplifier, which is a feature of the present embodiment.

A part of the signal output from the port i of the power combiner 10 is extracted by the power divider 83. Then, the extracted signal is divided by the power divider 84 into 2
Be distributed.

One of the two divided signals is input to a distortion level detection circuit 86 through a band-pass filter 85 that passes a signal in a frequency band for which distortion is compensated by a pre-distortion circuit 6A. Here, by automatically adjusting the vector adjuster 69 by the control circuit 90 so that the detected distortion signal level is minimized, the distortion compensation by the pre-distortion method can always maintain the optimal suppression state.

The other signal divided into two by power divider 84 is input to carrier level detection circuit 87. Here, the vector adjuster 5 is automatically adjusted by the control circuit 90 so that the detected carrier signal level is minimized.

On the other hand, a pilot signal oscillated from pilot signal oscillator 81 is injected into main amplifier 7 through power combiner 82.

The pilot signal is a signal having a frequency component higher than the carrier frequency that does not overlap with the distortion component when the distortion component generated on the higher frequency side than the carrier band is mainly suppressed by the feedforward method. In the feedforward method, it is determined whether or not distortion has been suppressed based on whether or not the injected pilot signal has been suppressed.

A part of the signal output from the port m of the power combiner 4 is extracted by the power divider 88,
The signal is input to a pilot level detection circuit 89. here,
By automatically adjusting the vector adjuster 12 by the control circuit 90 so that the detected pilot signal level is minimized, the distortion compensation by the feedforward method is as follows.
The optimal suppression state can always be maintained.

In the second embodiment, the circuit configuration using the distortion generating power amplifier 68 as the distortion generating circuit 72 has been described. However, the present invention is not limited to this. Is also good. Also, the circuit configuration is not limited to this, and may be configured only with the distortion generating power amplifier 68.

Further, in the above-described Embodiment 2, a description has been given of a configuration example in which a pilot signal of one frequency is injected, but pilot signals of a plurality of frequencies having different frequencies may be injected.

In the second embodiment, the pre-distortion circuit 6A includes the vector adjuster 5 and the power combiner 8
2 has been described, but it is clear that the same operation can be performed even when provided between the power distributor 3 and the vector adjuster 5.

When the vector adjusters 5 and 69 are not adjusted simultaneously, the common signal level detection circuit is switched by a switch circuit. It is apparent that the same operation is performed even when the circuit 92 is switched by the switch circuit 91. In this case, the control circuit 90 may switch the switch circuit 91.

(Embodiment 3) Next, Embodiment 3
FIG. 5 is a configuration diagram of the feedforward amplifier in FIG.
The configuration of the feedforward amplifier according to the present embodiment will be described with reference to FIG.

In FIG. 5, 31 is a power divider, 32 is an input signal level detection circuit, 34 is a switch circuit, 35 is a termination resistor, 36 is an auxiliary amplifier power switch circuit, and 37 is an input signal level detection circuit 32. This is a control circuit for switching the switch circuit 34 and the auxiliary amplifier power switch circuit 36 according to the input signal level. In addition,
The power distributor 31 and the input signal level detection circuit 32 constitute an input signal level detection unit 33.

The input signal level detection circuit 32 corresponds to the input signal level detection means of the present invention.

[0094] The feedforward amplifier according to the present embodiment has a structure in which the output power is considerably reduced from the rated output.
This is a feedforward amplifier in which distortion suppression is performed only by a predistortion method to improve efficiency at low output. The output power (output power) can be easily known by converting the detected input signal level.

Next, the operation of the feedforward amplifier according to the present embodiment will be described mainly with reference to FIG. 6 which is an efficiency characteristic diagram with respect to the output power of the feedforward amplifier.

The input signal level input from the input terminal 1 detected by the input signal level detection circuit 32 is P1 (dB).
m) or more, the control circuit 37 connects the common terminal 34a and the output switching terminal 34b of the switch circuit 34 and turns on the auxiliary amplifier power switch circuit 36. In this case, distortion suppression is performed using both the predistortion method and the feedforward method. Note that the input signal level P1 (dBm) is the output power P
out1 (dBm).

When the input signal level is equal to or lower than P1 (dBm), the control circuit 37 connects the common terminal 34a and the output switching terminal 34c of the switch circuit 34, and turns off the auxiliary amplifier power switch circuit 36. In this case, the distortion level generated in the main amplifier 7 decreases, and
This is because high-order intermodulation distortion does not occur, and the distortion can be sufficiently suppressed only by the pre-distortion method. Further, since the auxiliary amplifier power switch circuit 36 is turned off, the power consumed by the auxiliary amplifier 13 becomes zero.
Thus, as shown in FIG. 6, the efficiency at the time of low output can be improved.

In the third embodiment, the description has been given of the configuration example in which the pre-distortion circuit 6 is provided between the vector adjuster 5 and the main amplifier 7, but the power distributor 3 and the vector adjuster 5 Obviously, the same operation will be performed even if provided between them.

In the third embodiment, the input terminal 1
The switching of the switch circuit 34 and the auxiliary amplifier power switch circuit 36 is performed according to the input signal level immediately after the above. However, the present invention is not limited to this. It is clear to do. In this case, the input signal level detection unit 33 may be inserted at a position where the signal level is detected.

(Embodiment 4) Next, Embodiment 4
FIG. 7 is a configuration diagram of the feedforward amplifier in FIG.
The configuration of the feedforward amplifier according to the present embodiment will be described with reference to FIG.

The feedforward amplifier according to the present embodiment has a configuration similar to that of the above-described feedforward amplifier according to the present embodiment.
2 is a switch circuit, and 43 is a transmission line.

The transmission line 43 corresponds to the transmission line of the present invention, the switch circuit 41 corresponds to the first switch circuit of the present invention, and the switch circuit 42 corresponds to the second switch circuit of the present invention.

The feedforward amplifier according to the fourth embodiment of the present invention selects whether to perform distortion suppression using both the predistortion method and the feedforward method or to perform distortion suppression using only the feedforward method according to the output power. This is a feedforward amplifier provided with a means for performing the above operation.

Next, the operation of the feedforward amplifier according to the present embodiment will be described.

The input signal level input from the input terminal 1 detected by the input signal level detection circuit 32 is P2 (dB).
m) or more, the control circuit 37 connects the common terminal 41a of the switch circuit 41 to the output switching terminal 41b, and connects the common terminal 42a of the switch circuit 42 to the output switching terminal 42b. In this case, distortion suppression is performed using both the predistortion method and the feedforward method.

When the input signal level is equal to or lower than P2 (dBm), the control circuit 37 connects the common terminal 41a of the switch circuit 41 and the output switching terminal 41c, and connects the common terminal 42a of the switch circuit 42 and the output switching terminal 42c.
And connect. In this case, since the distortion level generated in the main amplifier 7 is low, the distortion can be sufficiently suppressed only by the feedforward method.

A circuit configuration as shown in FIG. 8, which is an explanatory diagram of a circuit configuration in which a transmission line is replaced by a delay circuit of a predistortion circuit, is also conceivable.

In FIG. 8, reference numeral 70 denotes a switch circuit;
Is a terminating resistor. In FIG. 8, the transmission line 43 of FIG.
Delay circuit 63 constituting pre-distortion circuit 6B
Is substituted.

The input signal level input from the input terminal 1 detected by the input signal level detection circuit 32 is P2 (dB).
m) or more, the control circuit 37 connects the common terminal 70a of the switch circuit 70 to the output switching terminal 70b. In this case, distortion suppression is performed using both the predistortion method and the feedforward method. When the input signal level is equal to or lower than P2 (dBm), the control circuit 37 connects the common terminal 70a of the switch circuit 70 to the output switching terminal 70c. In this case, since the signal from the distortion generating circuit 72 is not injected into the power combiner 62, and therefore is not injected into the main amplifier 7, as a result, the distortion is suppressed only by the feedforward method.

In the fourth embodiment, the switch circuit 70 is used to prevent the signal from the distortion generating circuit 72 from being injected into the main amplifier 7.
It is apparent that the same operation is performed even if the vector adjuster 69 is adjusted so as to attenuate the signal from the distortion generating circuit 72 to the maximum instead of using.

In the fourth embodiment, the input terminal 1
The switching of the switch circuit 34 and the auxiliary amplifier power switch circuit 36 is performed according to the input signal level immediately after the above, but the present invention is not limited to this. Is clear. In this case, the input signal level detection unit 33 may be inserted at a position where the signal level is detected.

FIG. 9 is an explanatory diagram of a circuit configuration having both a switch circuit for switching use / non-use of the predistortion method and a switch circuit for switching use / non-use of the feedforward method. A configuration is also conceivable. That is, as shown in FIG. 9, by combining the function of the third embodiment with the function of the fourth embodiment, the predistortion method and the feedforward method are used in combination according to the output power. It is clear that distortion suppression can be performed by switching to only the system. Specifically, (1) when the signal level of the detected input signal is equal to or less than a first predetermined value and larger than a second predetermined value which is a value smaller than the first predetermined value, The function of the predistortion compensating circuit may be stopped, and (2) the operation of the auxiliary amplifier may be stopped when the signal level of the input signal is equal to or less than a second predetermined value.

(Embodiment 5) FIG. 10 is a configuration diagram of a feedforward amplifier according to Embodiment 5 of the present invention. In FIG. 10, 63, 66, and 76 are delay lines as delay circuits, and 75 is a power divider. Power dividers 3, 61, 75, power combiners 62, 65, delay line 6
3, 66, the vector adjusters 67 and 69, and the distortion generating power amplifier 68 constitute a predistortion circuit 6C. The delay lines 66 and 76 constitute the delay line 8 as a delay circuit.

The power splitter 61 corresponds to the sixth power splitter of the present invention, the distortion generating power amplifier 68 corresponds to the distortion generating circuit of the present invention, and the vector adjuster 67 corresponds to the third power splitter of the present invention. , The delay circuit 63 corresponds to the third delay circuit of the present invention, and the power combiner 62 corresponds to the second power combiner of the present invention.

The predistortion circuit according to the fifth embodiment of the present invention is a feedforward amplifier using the whole or a part of the delay line 8 forming the feedforward circuit for the delay line forming the predistortion circuit 6C. .

Next, the operation of the feedforward amplifier according to the present embodiment will be described. Here, the description of the operation principle of the entire feedforward amplifier is omitted, and only the operation principle of the predistortion circuit 6C will be described.

An input signal containing a plurality of carrier frequency components input from input terminal 1 is input to port a of power divider 3. The signal input to the port a of the power divider 3 is split into two and output from the ports b and c, respectively.

The signal output from port b is split into two by power splitter 61. One of the two divided output signals is input to the power combiner 62 through the delay line 63. The other of the two output signals is amplified by the distortion generating power amplifier 68 through the vector adjuster 67 and input to the power combiner 65.

The signal output from the port c is input to the power combiner 65 through the delay line 66 and the power divider 75, and is combined with the output signal from the distortion generating power amplifier 68 described above. Here, the vector adjuster 6 controls the carrier frequency components of the two signals so that they have the same amplitude and opposite phases.
By adjusting the delay line 7 and the delay line 66, the carrier frequency component is canceled from the power combiner 65, and a signal including at least a distortion component in a frequency band for which distortion compensation is performed by the predistortion circuit 6C is output.

The signal output from the power combiner 65 is input to the power combiner 62 through the vector adjuster 69.
The output signal from the delay line 63 is combined with the output signal. The vector adjuster 69 is adjusted so that the distortion component of the main amplifier 7 generated in the frequency band for performing distortion compensation is suppressed to the maximum.

The signal synthesized by power combiner 62 is output from port n.

Note that the whole or a part of the delay line forming the feedforward circuit is used as the delay line forming the predistortion circuit, and a circuit configuration as shown in FIG. 11, which is an explanatory diagram of another circuit configuration. This will also be explained.

In FIG. 11, power distributors 3, 64, 7
5, power combiners 62 and 65, delay lines 63 and 66, vector adjusters 67 and 69, and power amplifier 68 for distortion generation
Constitute the pre-distortion circuit 6D. The delay lines 63 and 76 constitute a delay line 8 'as a delay circuit.

Here, too, the pre-distortion circuit 6D
Only the operation principle of will be described.

An input signal including a plurality of carrier frequency components input from input terminal 1 is input to port a of power divider 3. The signal input to the port a of the power divider 3 is split into two and output from the ports b and c, respectively.

The signal output from port b is split into two by power splitter 64. One of the two divided output signals is passed through a vector adjuster 67 to generate a distortion-generating power amplifier 6.
The signal is amplified at 8 and input to the power combiner 65. The other of the two output signals is input to the power combiner 65 through the delay line 66 and is combined with the output signal from the distortion-amplifying power amplifier 68. Here, by adjusting the vector adjuster 67 and the delay line 66 so that the carrier frequency components of both signals have the same amplitude and opposite phases, the carrier frequency component is canceled from the power combiner 65, and at least the pre-distortion is performed. The circuit 6D outputs a signal including a distortion component in a frequency band for which distortion compensation is performed. The signal output from the power combiner 65 is input to the power combiner 62 through the vector adjuster 69.

The signal output from the port c is input to the power combiner 62 through the delay line 63 and the power divider 75, and is combined with the output signal from the vector adjuster 69 described above. The vector adjuster 69 is adjusted so that the distortion component of the main amplifier 7 generated in the frequency band for performing distortion compensation is suppressed to the maximum.

The signal synthesized by power combiner 62 is output from port n.

As described above, by adopting the circuit configurations shown in FIGS. 10 and 11, the number of circuit components can be reduced.

In the fifth embodiment, the description has been given of the configuration using the delay line as the delay circuit. However, the present invention is not limited to this, and another circuit configuration having a delay function may be used.

In the above, the first to fifth embodiments have been described in detail.

The present invention also includes a communication device using the feedforward amplifier of the present invention and used for, for example, a base station device of a mobile communication device.

In the above-described embodiment,
Distortion was emphasized by the feed-forward method for the high-frequency band, and the pre-distortion method was compensated for the low-frequency band. However, the present invention is not limited to this. For example, it is also possible to perform important distortion suppression by a feedforward method on a low-frequency band and perform compensation by a pre-distortion method on a high-frequency band. In short, the second vector adjuster of the present invention is:
(1) Suppression of only the level of a distortion component occurring in a predetermined frequency range within a suppression target frequency range in which a distortion component to be suppressed occurs, or (2) Generation of a distortion component in a predetermined frequency range The level of the distortion component to be suppressed is adjusted so as to be greater than the level of the distortion component generated in a frequency range other than the predetermined frequency range in the frequency range to be suppressed, and the predistortion compensation circuit of the present invention is provided. May be adjusted so as to at least suppress the level of the distortion component generated in a frequency range other than the predetermined frequency range.

However, since it is often difficult to largely suppress distortion by the pre-distortion method, (1) the priority distortion suppression by the feed forward method is performed on the band with a high distortion level, and (2) the distortion level In many cases, more effective suppression can be achieved by performing compensation using the pre-distortion method for a band having a lower frequency.

In the above-described embodiment,
By using both the feedforward method and the predistortion method, both the high-frequency side and the low-frequency side where distortion occurs are suppressed. But,
However, the present invention is not limited to this. For example, when it is known that the distortion level occurs mainly on one of the high frequency side and the low frequency side and the distortion level on the other side is negligibly small. In order to solve this problem, a feed-forward scheme may be considered in which distortion is suppressed only on the above-described one side on which substantial distortion occurs. In short, the second vector adjuster of the present invention performs (1) suppression of only the level of the distortion component occurring in a predetermined frequency range within the suppression target frequency range in which the distortion component to be suppressed occurs. As described above, or (2) the suppression of the level of the distortion component occurring in the predetermined frequency range becomes larger than the suppression of the level of the distortion component occurring in the frequency range other than the predetermined frequency range in the frequency range to be suppressed. It should just be adjusted as follows.

Whether the higher distortion level is on the high frequency side or on the low frequency side depends mainly on the circuit configuration of the feedforward amplifier, but may also depend on the input signal input from the input terminal. Considering such a case,
Switch means for switching which side of the distortion suppression is performed by which method in accordance with the input signal may be provided.
Of course, as described above, even when the distortion is suppressed only by the feedforward method, the switch means for detecting the frequency range in which substantial distortion occurs and performing switching for suppressing the distortion in the detected frequency range. May be provided.

For example, by utilizing the circuit configuration of the feedforward amplifier shown in FIG. 14, among the distortion components to be suppressed, the distortion component occurring in a predetermined frequency range is out of the predetermined frequency range. May be adjusted so as to be larger than the distortion component generated in the frequency range of.
FIG. 14 is a configuration diagram of a feedforward amplifier that can switch which distortion suppression is performed and which method.

More specifically, the feedforward amplifier shown in FIG. 14 has a configuration similar to that of the feedforward amplifier of the second embodiment (see FIG. 3), but has an oscillation frequency of Pilot signal oscillator 81 'that can be adjusted to fall within the vicinity of a predetermined frequency range
A power divider (fourth power divider) 84 ′ that divides the other output signal of the power divider 83, which inputs one output signal to the vector adjuster 12, and a first power divider 84 ′ And a low-pass distortion level detection circuit 86 'for detecting the signal level of the output signal of the low-pass distortion signal band-pass filter.
A high-frequency distortion signal band-pass filter 185 connected to the second output terminal of the power divider 84 ′; and a high-frequency distortion detecting the signal level of the output signal of the high-frequency distortion signal band-pass filter 185. The pre-distortion circuit 6A and the pilot signal oscillator 81 'are based on the level detection circuit 186 and (1) the signal level detected by the low-frequency distortion level detection circuit 86' and the signal level detected by the high-frequency distortion level detection circuit 186. And (2) the vector adjuster 5 based on the signal level detected by the carrier level detection circuit 87,
(3) It is characterized in that a control circuit (control means) 90 'for automatically adjusting each of the vector adjusters 12 based on the signal level detected by the pilot level detection circuit 89 is provided.

For example, the low-frequency distortion level detection circuit 86 '
The signal level detected by the circuit is high-distortion level detection circuit 18
If the signal level is larger than the signal level detected by the pilot signal oscillator 6, the vector adjuster 69 of the pre-distortion circuit 6A is adjusted so that the signal level detected by the high-frequency distortion level detection circuit 186 is minimized. After adjusting the oscillation frequency of 81 'to be in the vicinity of the low frequency side,
The vector adjuster 12 is adjusted based on the signal level detected by the pilot level detection circuit 89.

In short, the automatic adjustment of the predistortion compensating circuit and the pilot signal oscillator is performed by (a) comparing the signal level detected by the low-frequency distortion level detecting circuit with the signal level detected by the high-frequency distortion level detecting circuit. Is larger, the predetermined frequency range is set to be the frequency range corresponding to the lower frequency side, and (b) the signal level detected by the higher frequency side distortion level detection circuit is used by the lower frequency side distortion level detection circuit. When the detected signal level is higher than the detected signal level, the predetermined frequency range is set to be a frequency range corresponding to the high frequency side, thereby making use of the above-described characteristics of the feedforward method and the predistortion method. Effective distortion suppression can be performed. Note that the frequency spectrum of the signal at each port is the same as that shown in FIGS.
(E), and in the latter case, as shown in FIG. 2 (a) to (e) in the same manner as in the second embodiment (the distortion injected by the pre-distortion circuit 6 is Is different).

The invention is a program for causing a computer to execute the functions of all or a part of the above-described feed-forward amplifier and communication device (or device, element, circuit, unit, etc.) of the present invention. It is a program that operates in cooperation with a computer. Of course, the computer of the invention is not limited to pure hardware such as a CPU, but also firmware, an OS,
Further, peripheral devices may be included.

The present invention also relates to a program for causing a computer to execute all or some of the steps (or steps, operations, operations, etc.) of the above-described feedforward amplification method of the present invention. It is a program that works in cooperation with.

Note that some means (or devices, elements, circuits, units, and the like) of the present invention, and some steps (or steps, operations, functions, and the like) of the present invention may be classified into a plurality of means or a plurality of means. It may mean some means or steps within a step, or some functions or some operations within one means or step.

Further, some devices (or elements, circuits, parts, etc.) of the present invention mean some of the plurality of devices, or some of the means in one device. (Or an element, a circuit, a part, or the like) or a part of the function of one means.

A computer-readable recording medium on which the program of the present invention is recorded is also included in the present invention. Further, one usage form of the program of the present invention may be a form in which the program is recorded on a computer-readable recording medium and operates in cooperation with the computer. One usage of the program of the present invention may be a mode in which the program is transmitted through a transmission medium, read by a computer, and operates in cooperation with the computer. The recording medium includes a ROM and the like, and the transmission medium includes a transmission medium such as the Internet, light, radio waves, and sound waves.

The configuration of the present invention may be realized by software or hardware.

Further, the present invention is a medium carrying a program for causing a computer to execute all or a part of the functions of all or part of the above-described feedforward amplifier and communication device of the present invention. The program is a medium that is readable by the computer and executes the function in cooperation with the computer.

The present invention also relates to a medium carrying a program for causing a computer to execute all or some of the operations of all or some of the steps of the above-described feedforward amplification method of the present invention. The medium that can execute the operation in cooperation with the computer is the program that can be read.

As described above, one of the distortion components generated on the high band side and the low band side of the carrier band is mainly subjected to the distortion suppression by the feed forward method, and the distortion suppression amount on the opposite side is thereby reduced. If the degradation is compensated for by the pre-distortion method, the distortion compensation range in the pre-distortion method is narrowed, and the distortion component can be suppressed efficiently, and as a result, the distortion suppression amount can be improved.

At the time of low output, since the distortion level generated in the main amplifier is low, the distortion is suppressed only by the pre-distortion method, and at this time, the operation of the auxiliary amplifier 13 is stopped to improve the efficiency at low output. Can be improved.

Further, by using all or a part of the delay circuit 8 constituting the feedforward circuit as the delay circuit constituting the predistortion circuit 6, the number of circuit components can be reduced.

[0152]

As is apparent from the above description,
The present invention has an advantage that a feedforward amplifier, a communication device, a feedforward amplification method, a program, and a medium that can efficiently suppress a distortion component can be provided.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a feedforward amplifier according to a first embodiment of the present invention;

2A is an explanatory diagram of a frequency spectrum of a signal at a port a. FIG. 2B is an explanatory diagram of a frequency spectrum of a signal at a port n. FIG. 2C is an explanatory diagram of a frequency spectrum of a signal at a port d. Explanatory diagram of the frequency spectrum of the signal at port i (e); Explanatory diagram of the frequency spectrum of the signal at port m

FIG. 3 is a configuration diagram of a feedforward amplifier according to a second embodiment of the present invention;

FIG. 4 is an explanatory diagram of a circuit configuration for switching a common signal level detection circuit by a switch circuit according to a second embodiment of the present invention;

FIG. 5 is a configuration diagram of a feedforward amplifier according to a third embodiment of the present invention.

FIG. 6 is an efficiency characteristic diagram with respect to output power of the feedforward amplifier according to the third embodiment of the present invention.

FIG. 7 is a configuration diagram of a feedforward amplifier according to a fourth embodiment of the present invention.

FIG. 8 is an explanatory diagram of a circuit configuration according to a fourth embodiment of the present invention, in which a transmission line is substituted by a delay circuit of a predistortion circuit;

FIG. 9 is an explanatory diagram of a circuit configuration having both a switch circuit for switching use / non-use of a predistortion method and a switch circuit for switching use / non-use of a feedforward method according to a fourth embodiment of the present invention;

FIG. 10 is a configuration diagram of a feedforward amplifier according to a fifth embodiment of the present invention.

FIG. 11 is an explanatory diagram of another circuit configuration according to the fifth embodiment of the present invention, which uses all or a part of the delay line forming the feedforward circuit as the delay line forming the predistortion circuit.

FIG. 12 is a configuration diagram of a conventional feedforward amplifier.

FIG. 13 is a configuration diagram of a predistortion circuit.

FIG. 14 is a configuration diagram of a feedforward amplifier according to the present invention that can switch which distortion suppression is performed in which method.

FIG. 15 (a): Frequency spectrum of a signal at port a (when a predetermined frequency range corresponds to a low frequency side)
(B); frequency spectrum of a signal at port n (when the predetermined frequency range corresponds to the low frequency side); (c); frequency spectrum of the signal at port d (the predetermined frequency range corresponds to the low frequency band). (D); frequency spectrum of a signal at port i (when a predetermined frequency range corresponds to the lower frequency side); (e); frequency spectrum of a signal at port m (predetermined) When the frequency range corresponds to the lower frequency side)

[Explanation of symbols]

1 input terminal 2 output terminal 3, 9, 31, 61, 64, 75, 83, 84, 88
Power divider 4, 10, 62, 65, 82 Power combiner 5, 12, 67, 69 Vector adjuster 6 Predistortion circuit 7 Main amplifier 8, 11, 63, 66, 76 Delay circuit 13 Auxiliary amplifier 32 Input signal level Detection circuit 33 Input signal level detection unit 34, 41, 42, 70, 91 Switch circuit 35, 71 Termination resistor 36 Auxiliary amplifier power switch circuit 37, 90 Control circuit 43 Transmission line 68 Distortion generation power amplifier 72 Distortion generation circuit 81 Pilot Signal oscillator 85 Band pass filter 86 Distortion level detection circuit 87 Carrier level detection circuit 89 Pilot level detection circuit 92 Signal level detection circuit

Continued on the front page (72) Inventor Toshimitsu Matsuyoshi 1006 Kazuma Kadoma, Osaka Pref.Matsushita Electric Industrial Co., Ltd. Inventor Seiji Fujiwara 4-3-1 Tsunashima Higashi, Kohoku-ku, Yokohama-shi, Kanagawa Prefecture F-term (reference) in Matsushita Communication Industrial Co., Ltd. 5J090 AA01 AA41 CA21 FA00 GN03 GN04 GN05 GN07 HA25 HA38 KA15 KA32 KA44 KA68 MA14 SA13 TA01 TA02 TA03 5J09 AA01 AA41 CA21 FA00 HA25 HA38 KA15 KA32 KA44 KA68 MA14 SA13 TA01 TA02 TA03 5K060 BB07 CC04 DD04 HH06 LL00

Claims (31)

[Claims] A first power divider that divides an input signal into two; a first vector adjuster that adjusts an amplitude and a phase of one output signal of the first power divider; A predistortion compensation circuit connected to a vector adjuster, a main amplifier for amplifying an output signal of the predistortion circuit, a second power divider for dividing an output signal of the main amplifier into two, A first delay circuit for delaying the other output signal of the first power divider; and a distortion detection for combining one output signal of the second power divider with the output signal of the first delay circuit. A power combiner, a second delay circuit for delaying the other output signal of the second power divider, and a second vector adjuster for adjusting the amplitude and phase of the output signal of the distortion detection combiner. And an auxiliary amplifier for amplifying an output signal of the second vector adjuster. And a distortion removing power combiner that combines the output signal of the second delay circuit and the output signal of the auxiliary amplifier. The second vector adjuster is (1) subject to suppression. Of the suppression target frequency range where the distortion component occurs, so that only the distortion component occurring in a predetermined frequency range is suppressed,
Or (2) the distortion component generated in the predetermined frequency range is suppressed so as to be greater than the suppression of the distortion component generated in a frequency range other than the predetermined frequency range in the frequency range to be suppressed. The feed-forward amplifier, wherein the predistortion compensation circuit is adjusted so that at least suppression of a distortion component occurring in a frequency range other than the predetermined frequency range is performed. 2. The feedforward amplifier according to claim 1, wherein the predetermined frequency range is an entire high-frequency band or a low-frequency side distortion signal band generated in the main amplifier. 3. The feedforward amplifier according to claim 1, wherein said predistortion compensation circuit is provided between said first power divider and said first vector adjuster. 4. A first power combiner for combining at least one pilot signal oscillator, an output signal of the pilot signal oscillator and an output signal of the predistortion compensation circuit, and outputting the combined signal to the main amplifier. A third power divider that divides the output signal of the distortion detection power combiner into two, and inputs one output signal to the second vector adjuster; and the other of the third power divider A fourth power divider for dividing an output signal into two, a band-pass filter connected to one output terminal of the fourth power divider, and a distortion level for detecting a signal level of an output signal of the band-pass filter A detection circuit; a carrier level detection circuit for detecting a signal level of the other output signal of the fourth power divider; a fifth power divider for dividing an output signal of the distortion removing power combiner into two; The fifth power A pilot level detection circuit for detecting the signal level of one output signal of the distributor; (1) the predistortion compensation circuit based on the signal level detected by the distortion level detection circuit; and (2) the carrier level detection circuit. Control means for automatically adjusting the first vector adjuster based on the detected signal level, and (3) automatically adjusting the second vector adjuster based on the signal level detected by the pilot level detection circuit, 2. The feedforward amplifier according to claim 1, wherein the other output signal of the fifth power divider is supplied to a subsequent stage. 5. An output signal of the distortion detection power combiner is set to 2
A third power splitter that splits and outputs one output signal to the second vector adjuster; a fourth power splitter that splits the other output signal of the third power splitter into two; A band-pass filter connected to one output terminal of the fourth power divider; controlling the output signal of the band-pass filter and the other output signal of the fourth power divider from the control unit. A switch circuit for selecting and switching by a signal; a signal level detection circuit for detecting a signal level of the selected signal among an output signal of the bandpass filter and the other output signal of the fourth power divider; According to the signal level detected by the signal level detection circuit, (1) when the output signal of the band-pass filter is selected, the predistortion compensation circuit is replaced by (2) the fourth power divider. Out of the other Signal if selected, the first vector regulator, according to claim 1, wherein the feed-forward amplifier, respectively and control means for automatically adjusting. 6. The feedforward amplifier according to claim 4, wherein said control means stops the operation of said auxiliary amplifier or the function of said predistortion compensation circuit based on a predetermined condition. 7. An input signal level detecting means for detecting a signal level of the input signal, wherein the operation of the auxiliary amplifier or the function of the predistortion circuit is stopped based on the predetermined condition, 7. The feedforward amplifier according to claim 6, wherein the control means stops the operation of the auxiliary amplifier when a signal level of the detected input signal is equal to or less than a predetermined value. 8. An input signal level detecting means for detecting a signal level of the input signal, wherein the operation of the auxiliary amplifier or the function of the predistortion circuit is stopped based on the predetermined condition, 7. The feedforward amplifier according to claim 6, wherein the control means stops the function of the predistortion compensation circuit when the signal level of the detected input signal is equal to or less than a predetermined value. 9. The method according to claim 1, further comprising: input signal level detection means for detecting a signal level of the input signal, wherein the operation of the auxiliary amplifier or the function of the predistortion circuit is stopped based on the predetermined condition. (1) When the signal level of the detected input signal is equal to or less than a first predetermined value and larger than a second predetermined value that is smaller than the first predetermined value. ,
7. The feedforward according to claim 6, wherein the function of the predistortion compensation circuit is stopped, and (2) the operation of the auxiliary amplifier is stopped when the signal level of the input signal is equal to or less than the second predetermined value. amplifier. 10. A transmission line disposed in parallel with said predistortion compensation circuit, an input side of said predistortion compensation circuit and said transmission line, and an output side of said predistortion compensation circuit and said transmission line. The first and second switch circuits for switching between the pre-distortion compensation circuit side and the transmission line side respectively disposed are provided, and the function of the pre-distortion compensation circuit is stopped. First,
7. The feedforward amplifier according to claim 6, wherein a second switch circuit is connected to the transmission line. 11. The input signal level detecting means is provided in a signal path including an input signal component.
The feedforward amplifier according to any one of the above. 12. A pre-distortion compensating circuit, comprising: a sixth power splitter for splitting a signal into two, a distortion generating circuit for receiving one output signal of the sixth power splitter and generating a distortion. A third step of adjusting the amplitude and phase of the output signal of the distortion generating circuit.
, A third delay circuit for delaying the other output signal of the sixth power divider, and an output signal of the third vector adjuster and an output signal of the third delay circuit. The feedforward amplifier according to any one of claims 1 to 10, comprising a second power combiner for combining. 13. A seventh power divider for dividing a signal into two, and a fourth vector adjuster for adjusting an amplitude and a phase of one output signal of the seventh power divider. A power amplifier for distortion amplifying an output signal of the fourth vector adjuster, a fourth delay circuit for delaying another output signal of the seventh power divider, and a power amplifier for distortion generation And a third power combiner for combining the output signal of the second delay circuit and the output of the fourth delay circuit.
2. The feedforward amplifier according to 2. 14. The automatic adjustment of the predistortion compensating circuit based on the signal level detected by the distortion level detecting circuit is to adjust the amplitude and phase of the third vector adjuster. A feedforward amplifier as described. 15. The feedforward amplifier according to claim 12, wherein stopping the function of the predistortion compensation circuit means that an output signal from the distortion generation circuit is not input to the second power combiner. 16. The feedforward amplifier according to claim 12, wherein said distortion generating circuit is constituted only by a distortion generating power amplifier for amplifying an input signal. 17. The feedforward amplifier according to claim 12, wherein the third delay circuit is configured using all or a part of the first delay circuit. 18. The feedforward amplifier according to claim 13, wherein the fourth delay circuit is configured using all or a part of the first delay circuit. 19. The feedforward amplifier according to claim 13, wherein said distortion generating power amplifier is constituted by a non-linear device. 20. The feedforward amplifier according to claim 1, wherein a distortion component generated in the predetermined frequency range is larger than a distortion component generated in a frequency range other than the predetermined frequency range. 21. Adjustment is performed such that, among the distortion components to be suppressed, a distortion component generated in a predetermined frequency range is larger than a distortion component generated in a frequency range other than the predetermined frequency range. 2. The feedforward amplifier of claim 1, wherein said feedforward amplifier is implemented. 22. A pilot signal oscillator that can be adjusted so that an oscillation frequency falls within the vicinity of the predetermined frequency range, and an output signal of the pilot signal oscillator and an output signal of the predistortion compensation circuit are combined. A first power combiner that outputs to the main amplifier; and a third power that divides an output signal of the distortion detection power combiner into two, and inputs one output signal to the second vector adjuster. A fourth power splitter for splitting the other output signal of the third power splitter into three; a low-frequency distortion signal connected to a first output terminal of the fourth power splitter A band-pass filter, a low-frequency distortion level detection circuit for detecting a signal level of an output signal of the low-frequency distortion signal band-pass filter, and a high-frequency signal connected to a second output terminal of the fourth power divider. An area-side distortion signal band-pass filter; A high-frequency distortion level detection circuit that detects a signal level of an output signal of the high-frequency distortion signal band-pass filter; a carrier level detection circuit that detects a signal level of a third output signal of the fourth power divider; A fifth power divider for dividing the output signal of the distortion removing power combiner into two, a pilot level detection circuit for detecting a signal level of one output signal of the fifth power divider, The predistortion compensating circuit and the pilot signal oscillator are determined by the signal level detected by the low-frequency distortion level detection circuit and the signal level detected by the high-frequency distortion level detection circuit, and (2) the carrier level detection circuit The first vector adjuster according to the detected signal level;
(3) control means for automatically adjusting each of the second vector adjusters based on the signal level detected by the pilot level detection circuit, and the other output signal of the fifth power divider is provided at a subsequent stage. 22. The feedforward amplifier according to claim 21, which is provided. 23. The automatic adjustment of the predistortion compensating circuit and the pilot signal oscillator includes the steps of: (a) detecting a signal level detected by the low-frequency distortion level detection circuit by the high-frequency distortion level detection circuit; If it is higher than the signal level,
The predetermined frequency range is set to be a frequency range corresponding to the low frequency side, and (b) the signal level detected by the high frequency side distortion level detection circuit is detected by the low frequency side distortion level detection circuit 23. The feedforward amplifier according to claim 22, wherein when the signal level is higher than the set signal level, the predetermined frequency range is set to be a frequency range corresponding to the high frequency side. 24. A first power divider for dividing an input signal into two, a first vector adjuster for adjusting an amplitude and a phase of one output signal of the first power divider, A main amplifier for amplifying the output signal of the vector adjuster, a second power divider for dividing the output signal of the main amplifier into two, and a first for delaying the other output signal of the first power divider. A distortion detection power combiner that combines one output signal of the second power divider with the output signal of the first delay circuit; and the other output of the second power divider. A second delay circuit that delays a signal; a second vector adjuster that adjusts the amplitude and phase of an output signal of the distortion detection combiner; and an auxiliary amplifier that amplifies an output signal of the second vector adjuster. An output signal of the second delay circuit and the auxiliary signal; A power combiner for removing distortion that combines the output signal of the width unit; and the second vector adjuster includes: (1) a predetermined frequency range within a frequency range to be suppressed in which a distortion component to be suppressed occurs; In order to suppress only the distortion component that occurs in the frequency range,
Or (2) the distortion component generated in the predetermined frequency range is suppressed so as to be greater than the suppression of the distortion component generated in a frequency range other than the predetermined frequency range in the frequency range to be suppressed. Feed-forward amplifier. 25. A communication device using the feedforward amplifier according to claim 1. 26. Dividing the input signal into two using a first power divider; and amplitude and phase of one output signal of the first power divider using a first vector adjuster. Adjusting the output signal of the predistortion circuit connected to the first vector adjuster using a main amplifier; and adjusting the main amplifier using a second power divider. Distributing the output signal of the first power divider into two, delaying the other output signal of the first power divider using a first delay circuit, and distorting the second output signal using a distortion detecting power combiner. Combining one output signal of the first power divider with the output signal of the first delay circuit, and delaying the other output signal of the second power divider using a second delay circuit. Using a step and a second vector adjuster Adjusting the amplitude and phase of the output signal of the distortion detection combiner; amplifying the output signal of the second vector adjuster using an auxiliary amplifier; and using a distortion removal power combiner. Combining the output signal of the second delay circuit and the output signal of the auxiliary amplifier with the second vector adjuster. (1) A frequency range to be suppressed in which a distortion component to be suppressed occurs. Among them, so that only the distortion component generated in a predetermined frequency range is suppressed,
Or (2) adjusting the suppression of the distortion component occurring in the predetermined frequency range to be larger than the suppression of the distortion component occurring in the frequency range other than the predetermined frequency range in the suppression target frequency range. And a step of adjusting the predistortion circuit such that distortion components occurring in a frequency range other than the predetermined frequency range are suppressed at least. 27. Dividing the input signal into two using a first power divider; and amplitude and phase of one output signal of the first power divider using a first vector adjuster. Adjusting the output signal of the first vector adjuster using a main amplifier; and splitting the output signal of the main amplifier into two using a second power divider. Delaying the other output signal of the first power divider using a first delay circuit; one output signal of the second power divider using a distortion detecting power combiner Combining the output signal of the second power divider with the output signal of the first delay circuit; delaying the other output signal of the second power divider using a second delay circuit; And the output of the distortion detection combiner Adjusting the amplitude and phase of the signal, amplifying the output signal of the second vector adjuster using an auxiliary amplifier, and adjusting the output signal of the second delay circuit using a power combiner for removing distortion. Combining the output signal and the output signal of the auxiliary amplifier; and setting the second vector adjuster to a predetermined frequency range within a frequency range to be suppressed in which (1) a distortion component to be suppressed occurs. In order to suppress only the distortion component that occurs,
Or (2) adjusting the suppression of the distortion component occurring in the predetermined frequency range to be larger than the suppression of the distortion component occurring in the frequency range other than the predetermined frequency range in the suppression target frequency range. And a feed-forward amplification method. 28. The feedforward amplification method according to claim 26, wherein the input signal is divided into two by using the first power divider.
Distributing, adjusting the amplitude and phase of one output signal of the first power divider using a first vector adjuster, and using the main amplifier to control the first vector adjuster Amplifying the output signal of the predistortion compensating circuit connected to the power amplifier, dividing the output signal of the main amplifier into two using a second power divider, and using the first delay circuit. Delaying the other output signal of the first power divider, and using a distortion detecting power combiner to output one output signal of the second power divider and an output signal of the first delay circuit. And combining the second
Delaying the other output signal of the second power splitter using the delay circuit, and adjusting the amplitude and phase of the output signal of the distortion detection synthesizer using a second vector adjuster Amplifying the output signal of the second vector adjuster using an auxiliary amplifier;
Combining the output signal of the second delay circuit and the output signal of the auxiliary amplifier using a power combiner for removing distortion, and (1) subjecting the second vector adjuster to suppression. Among the suppression target frequency ranges in which the distortion component occurs, only the distortion component occurring in a predetermined frequency range is suppressed, or (2) the suppression of the distortion component occurring in the predetermined frequency range is performed by the suppression. And adjusting the pre-distortion compensating circuit so that it becomes larger than suppression of a distortion component occurring in a frequency range other than the predetermined frequency range. And a program for causing a computer to execute all or a part of the step of adjusting so as to suppress at least the distortion component generated in the computer. 29. The feedforward amplification method according to claim 26, wherein the input signal is divided into two by utilizing the first power divider.
Distributing, adjusting the amplitude and phase of one output signal of the first power divider using a first vector adjuster, and using the main amplifier to control the first vector adjuster Amplifying the output signal of the predistortion compensating circuit connected to the power amplifier, dividing the output signal of the main amplifier into two using a second power divider, and using the first delay circuit. Delaying the other output signal of the first power divider, and using a distortion detecting power combiner to output one output signal of the second power divider and an output signal of the first delay circuit. And combining the second
Delaying the other output signal of the second power splitter using the delay circuit, and adjusting the amplitude and phase of the output signal of the distortion detection synthesizer using a second vector adjuster Amplifying the output signal of the second vector adjuster using an auxiliary amplifier;
Combining the output signal of the second delay circuit and the output signal of the auxiliary amplifier using a power combiner for removing distortion, and (1) subjecting the second vector adjuster to suppression. Among the suppression target frequency ranges in which the distortion component occurs, only the distortion component occurring in a predetermined frequency range is suppressed, or (2) the suppression of the distortion component occurring in the predetermined frequency range is performed by the suppression. And adjusting the pre-distortion compensating circuit so that it becomes larger than suppression of a distortion component occurring in a frequency range other than the predetermined frequency range. A medium carrying a program for causing a computer to execute all or a part of the step of adjusting so that at least suppression of distortion components occurring is performed, and Physical medium capable. 30. The feedforward amplification method according to claim 27, wherein the input signal is divided into two by using the first power divider.
Distributing, adjusting the amplitude and phase of one output signal of the first power divider using a first vector adjuster, and using the main amplifier to control the first vector adjuster Amplifying the output signal of
Distributing the output signal of the main amplifier into two using a power divider of the first embodiment, and the first delay circuit using a first delay circuit.
Delaying the other output signal of the power divider, and combining the one output signal of the second power divider with the output signal of the first delay circuit using a distortion detecting power combiner. Performing the operation, delaying the other output signal of the second power divider using a second delay circuit, and outputting the output signal of the distortion detecting combiner using a second vector adjuster. Adjusting the amplitude and phase of
Amplifying the output signal of the second vector adjuster using an auxiliary amplifier; and using the power combiner for removing distortion to convert the output signal of the second delay circuit and the output signal of the auxiliary amplifier. The synthesizing step and the second vector adjuster are performed such that (1) suppression of only a distortion component occurring in a predetermined frequency range within a suppression target frequency range in which a distortion component to be suppressed occurs is performed. Or (2) the suppression of the distortion component occurring in the predetermined frequency range is greater than the suppression of the distortion component occurring in the frequency range other than the predetermined frequency range in the suppression target frequency range. A program for causing a computer to execute all or a part of the adjusting step. 31. The feedforward amplification method according to claim 27, wherein the input signal is divided into two by using the first power divider.
Distributing, adjusting the amplitude and phase of one output signal of the first power divider using a first vector adjuster, and using the main amplifier to control the first vector adjuster Amplifying the output signal of
Distributing the output signal of the main amplifier into two using a power divider of the first embodiment, and the first delay circuit using a first delay circuit.
Delaying the other output signal of the power divider, and combining the one output signal of the second power divider with the output signal of the first delay circuit using a distortion detecting power combiner. Performing the operation, delaying the other output signal of the second power divider using a second delay circuit, and outputting the output signal of the distortion detecting combiner using a second vector adjuster. Adjusting the amplitude and phase of
Amplifying the output signal of the second vector adjuster using an auxiliary amplifier; and using the power combiner for removing distortion to convert the output signal of the second delay circuit and the output signal of the auxiliary amplifier. The synthesizing step and the second vector adjuster are performed such that (1) suppression of only a distortion component occurring in a predetermined frequency range within a suppression target frequency range in which a distortion component to be suppressed occurs is performed. Or (2) the suppression of the distortion component occurring in the predetermined frequency range is greater than the suppression of the distortion component occurring in the frequency range other than the predetermined frequency range in the suppression target frequency range. A medium that carries a program for causing a computer to execute all or a part of the adjusting step, and is a medium that can be processed by the computer.