KR20060038793A - Apparatus and method for multi amplifying in linear power amplifier - Google Patents

Abstract

The present invention provides a multi-amplification apparatus and method thereof for a linear power amplifier, comprising: a first switch for switching on a carrier signal; A control unit configured to perform a carrier canceler and an IMD canceller, and perform precompensation control; A multipath unit coupled between the main path and the error path separated by the first signal separator to perform parallel synthesized multipath amplification; An amplifying unit positioned at a next stage of the multi path unit to perform an error amplifying function and a main amplifying function; Including a signal combiner for receiving the output of the second delay line and the amplifier and performing an IMD canceler function and a power combiner function, add a pre-compensation function after the maximum rated output in the conventional feedforward LPA, and the main amplifier and the error. By configuring the amplifier as a parallel synthesized two-path amplifier using a switch, the output can be doubled, allowing the output to be doubled in the conventional feedforward LPA without adding one more LPA module.

Description

Apparatus and method for multi amplifying in linear power amplifier

1 is a block diagram of a conventional linear power amplifier,

FIG. 2 is a block diagram illustrating frequency and power spectrum of each block in FIG. 1.

3 is a flowchart illustrating a conventional linear power amplification method,

4 is a block diagram of a multi-amplification apparatus of a linear power amplifier according to the present invention,

5 is a flowchart illustrating a multi-amplification method of a linear power amplifier according to the present invention.

Explanation of symbols on the main parts of the drawings

21: first signal separation unit 22: first signal adjustment unit

23: main amplifier 24: directional coupler

25 first delay line 26 attenuator

27 carrier carrier 28 second delay line

29: second signal adjusting unit 40: first switch

50: control unit 60: multi amplification unit

61: second signal separator 62: third delay line

63: second switch 70: amplifier

80: signal coupling unit

The present invention relates to a linear power amplifier (LPA), and more particularly, to add a predistorter function after the maximum rated power in a conventional feed forward linear power amplifier (LPA), and the main amplifier and the error. The amplifier is configured as a parallel synthesized two-path amplifier using a switch, which doubles the output, making it suitable for multiplying the power of a linear power amplifier by doubling the output without adding one more LPA module in a conventional feedforward LPA. An amplifier device and a method thereof are provided.

In general, linear power amplifiers are devices that amplify the output to a required size in a linear manner.

1 is a block diagram of a conventional linear power amplifier.

As shown therein, a signal splitter 1 for separating the input signal into a main path and an error path; A first signal adjusting unit (2) which performs amplitude reduction, phase adjustment, and amplitude adjustment of the main signal separated by the signal separation unit (1); A main amplifying unit (3) for performing a main signal amplification by a gain on the output of the first signal adjusting unit (2); A directional coupler 4 for separating the main amplified signal output from the main amplifier 3 into a coupling signal of a predetermined signal and an input signal of a second delay line; A first delay line 5 for receiving a signal of an error path of the signal separation unit 1 and compensating for a time delay between a main amplified signal and a carrier; An attenuator (6) which receives the output of the directional coupler (4) and performs attenuation to match the magnitude of the main amplified signal and the carrier signal; A carrier canceler for shifting the phase of the main amplified signal outputted from the attenuator 6 by 180 degrees and outputting an IMD (Inter Modulation Distortion, distortion signal component, or error signal) signal in combination with the carrier signal (7). )Wow; A second delay line (8) receiving the output of the directional coupler (4) to compensate for the time delay between the main amplified signal and the error amplified signal; A second signal adjusting unit 9 which receives the output of the carrier canceller 7 and performs amplitude reduction, phase adjustment, and amplitude adjustment on an error signal; A forward control unit (10) for controlling the first and second signal adjusting units (2) and (9) so as to perform a carrier canceller and an IMD canceller; An error amplifying unit (11) which receives the output of the second signal adjusting unit (9) and amplifies the error signal by a gain; An IMD canceller 12 which receives a main amplified signal through the second delay line 8 and receives an error amplified signal through the error amplifying unit 11 and outputs a signal in which an IMD signal has been removed and summed; It consists of.

FIG. 2 is a block diagram illustrating frequency and power spectrum of each block in FIG. 1.

3 is a flowchart illustrating a conventional linear power amplification method.

As shown therein, determining whether the magnitude of the output signal is within the maximum rated output (ST1); If the magnitude of the output signal is within the maximum rated output, linear power amplification is performed by the feedforward control, and if the magnitude of the output signal is not within the maximum rated output, step ST2 is performed.

The operation of the prior art configured as described above will be described in detail with reference to the accompanying drawings.

First, as shown in FIGS. 1 and 2, the input carrier main signal is divided into a signal for generating an RF (Radio Frequency) signal from the signal separator 1 to the main amplifier 3 and an IMD signal (error signal).

The main RF signal is subjected to constant amplitude attenuation, phase adjustment, and amplitude adjustment through the first signal adjustment unit 2 so that only the carrier can be accurately canceled later through the carrier canceller 7, and then the main amplification unit ( 3) is entered.

In the main amplifier 3, a gain of 50dB or more is generally generated, and the power is amplified, but the IMD signal is produced together by nonlinear characteristics.

One path in the directional coupler 4 passes the signal to the second delay line 8 with almost no loss, and the other path couples a certain amount of signal to the carrier cancel path.

Meanwhile, the signal input to the first delay line 5 compensates for the time required in the process of amplifying by the main amplifier 3.

The carrier canceler 7 removes the carrier signal by subtracting the main carrier + IMD signal input through the attenuator 6 from the carrier passing through the first delay line 5 (-), and removes the IMD signal (error). Signal).

The IMD-only signal is now amplified by the second signal adjusting unit 9, the phase adjusting, and the amplitude adjusting, and then amplified by the error amplifier 11 and input to the IMD canceller 12.

The IMD canceller 12 outputs the main carrier + IMD signal and the error amplifier 11 input through the second delay line 8 to compensate for the time required in the process of amplifying the error amplifier 11. The added IMD signals are summed to remove the IMD signals generated by the main amplifier 3.

As a result, the signals generated by nonlinearity are externally generated to cancel the effects of nonlinearity by canceling each other with the same IMD signal.

This can be seen by referring to the signal waveform of each stage in FIG. 2.

However, this conventional technology has the following problems.

In other words, while using the error amplifier outputting the same output as the main amplifier, after all, only the rated output of the main amplifier is output, there is a very inefficient problem in terms of efficiency.

Therefore, the present invention has been proposed to solve the above conventional problems, and an object of the present invention is to add a pre-compensation function after the maximum rated output in a conventional feedforward LPA and use a main amplifier and an error amplifier by using a switch It provides a multi-amplification device and method for a linear power amplifier that can double the output by configuring a parallel synthesized two-path amplifier to double the output, thereby eliminating an additional LPA module from the conventional feedforward LPA. have.

In order to achieve the above object, a multi-amplification apparatus of a linear power amplifier according to an embodiment of the present invention,

A signal separating unit for separating an input signal, a first signal adjusting unit for adjusting the main signal separated from the signal separating unit, a main amplifying unit for amplifying the output of the first signal adjusting unit, and a separation of the main amplifying unit A directional coupler, a first delay line for delaying a signal of an error path separated by the signal separation unit, an attenuator for attenuating the output of the directional coupler, an output of the attenuator and an output of the first delay line. A linear power amplifier comprising a carrier canceler for outputting an IMD signal, a second delay line for delaying the output of the directional coupler, and a second signal adjuster for performing signal adjustment on the output of the carrier canceller. ,

A first switch positioned between the first signal separator and the first delay line to switch a carrier signal to be input to the first delay line or to a controller; Respectively controlling the first and second signal adjusting units to perform a carrier canceller and an IMD canceller, and perform pre-compensation control by receiving an error path signal switched by the first switch and a signal output from the signal combiner A controller; A multipath unit coupled between the main path and the error path separated by the first signal separator to perform parallel synthesized multipath amplification; An amplifying unit positioned at a next stage of the multi-path unit to perform an error amplifying function up to a maximum rated output, and performing a main amplifying function above the maximum rated output; Technical features of the present invention include a signal coupling unit configured to receive an output of the second delay line and the amplifier and perform an IMD canceller function up to a maximum rated output, and perform a power combining function above the maximum rated output.

In order to achieve the above object, a multi-amplification method of a linear power amplifier according to an embodiment of the present invention,

A first step of determining whether the magnitude of the output signal is within a maximum rated output; A second step of performing linear power amplification with feedforward control if the magnitude of the output signal is within the maximum rated output; And a third step of performing linear power amplification by precompensation control if the magnitude of the output signal is not within the maximum rated output.

Hereinafter, an embodiment according to the present invention, a multi-amplification apparatus for a linear power amplifier, and a method thereof will be described with reference to the accompanying drawings.

4 is a block diagram of a multi-amplification apparatus of a linear power amplifier according to the present invention.

As shown therein, a signal separation unit 21 for separating an input signal, a first signal adjustment unit 22 for adjusting the main signal separated by the signal separation unit 21, and the first signal adjustment unit A main amplifier 23 for amplifying the output of the signal 22, a directional coupler 24 for separating the main amplifier 23, and a signal for the error path separated in the signal separator 21 An IMD signal by adding the first delay line 25, the attenuation part 26 which attenuates the output of the directional coupler 24, the output of the attenuation part 26 and the output of the first delay line 25; A second signal for performing signal adjustment on a carrier canceler 27 for outputting a signal, a second delay line 28 for delaying an output of the directional coupler 24, and an output of the carrier canceler 27. In the linear power amplifier provided with the adjusting unit 29,

A first switch positioned between the first signal separator 21 and the first delay line 25 to switch a carrier signal to the first delay line 25 or to be input to the controller 50. 40; The first and second signal adjusting units 22 and 29 are respectively controlled to perform a carrier canceller and an IMD canceller, and the error path signal and the signal combiner 80 switched by the first switch 40 are controlled. A controller 50 which receives an output signal and performs predistorter control; A multi-path unit 60 connected between the main path and the error path separated by the first signal separator 21 to perform parallel synthesized multi-path amplification; An amplifying unit 70 located at a next stage of the multi-path unit 60 to perform an error amplifying function up to a maximum rated output, and to perform a main amplifying function above the maximum rated output; A signal combiner 80 configured to receive an output of the second delay line 28 and the amplifier 70 to perform an IMD canceller function up to a maximum rated output, and to perform a power combiner function above the maximum rated output; It is configured by.

The multi path unit 60 includes: a second signal separation unit 61 located at a next stage of the first signal adjustment unit 22 to separate a signal; A third delay line 62 for receiving and delaying the signal separated by the second signal separator 61; It further comprises a second switch 63 for receiving the signal of the third delay line 62 and the signal of the second signal adjusting unit 29 to be input to the amplifier 70 by switching.

In the above, if the magnitude of the output signal is within the maximum rated output, the control unit 50 controls to perform linear power amplification by the feed forward control to the first and second signal adjusting unit 29, the magnitude of the output signal If is not within the maximum rated output, it characterized in that the first and second signal adjusting unit 29 is controlled to perform linear power amplification by precompensation control.

The control unit 50 receives the final RF output as another input, and compensates for magnitude distortion component and phase distortion component, a magnitude inverse control signal and a phase inverse control signal. generating a signal to control predistortion.

5 is a flowchart illustrating a multi-amplification method of a linear power amplifier according to the present invention.

As shown therein, a first step ST11 for determining whether the magnitude of the output signal is within the maximum rated output power; A second step ST12 of performing linear power amplification by feedforward control when the magnitude of the output signal is within the maximum rated output power; If the magnitude of the output signal is not within the maximum rated output, a third step (ST13) of performing linear power amplification by precompensation control is performed.

Operation of the multi-amplification device and the method of the linear power amplifier according to the present invention configured as described above will be described in detail with reference to the accompanying drawings.

First, the present invention is to add a precompensation function after the maximum rated output in the conventional feed forward LPA, and to improve the output by doubling the output by configuring the main amplifier and the error amplifier as a parallel synthesized two-path amplifier using a switch.

Thus, the present invention adds two switches and one signal separator in the conventional feedforward LPA structure, and adds a precompensation function to the controller 50. Accordingly, the functions of the amplifier 70 and the signal combiner 80 are expanded.

The precompensation function is: first, a magnitude inverse control signal output function for compensating magnitude distortion of the output signal, and a second phase inverse control signal output function for compensating phase distortion. to be.

On the other hand, the magnitude of the output signal is the same as the conventional feedforward LPA until the maximum rated output of the main amplifier 23.

That is, the input carrier main signal is divided into a signal for generating an RF (Radio Frequency) signal from the signal separator 21 to the main amplifier 23 and an IMD signal (error signal).

Then, the main RF signal is subjected to constant amplitude attenuation, phase adjustment, and amplitude adjustment through the first signal adjustment unit 22 so that only the carrier can be accurately canceled later through the carrier canceler 27, and then the main amplification unit. Entered by (23).

In the main amplifier 23, a gain of 50dB or more is generally generated and power is amplified, but the IMD signal is generated together by nonlinear characteristics.

One path in the directional coupler 24 passes the signal to the second delay line 28 with little loss, and the other couples the signal to the carrier cancel path by coupling a certain amount of signal.

Meanwhile, the signal input to the first delay line 25 compensates for the time required in the process of amplifying by the main amplifier 23.

The carrier canceler 27 removes the carrier signal by subtracting the main carrier + IMD signal input through the attenuator 26 from the carrier passing through the first delay line 25 (-), and removes the IMD signal (error signal). )

Now, the IMD-only signal is attenuated by the second signal adjusting unit 29, phase adjustment, and amplitude adjustment, and then amplified by the amplifier 70 and input to the signal combiner 80.

In the signal combiner 80, the main carrier + IMD signal input through the second delay line 28, which compensates for the time required in the amplification unit 70, and the IMD output from the amplification unit 70. The sum of the signals removes the IMD signal generated by the main amplifier 23.

On the other hand, when the output signal size is output beyond the maximum rated output of the main amplifier 23 to operate as follows.

That is, when the output signal magnitude exceeds the maximum rated output of the main amplifier 23, the amplifier 70 is operated to perform a main amplification function, thereby converting the LPA into a structure of a parallel synthesized two-path amplifier to convert the output. Try to double it.

Therefore, when the switch operation is described first, the first switch 40 switches the output signal of the first signal separator 21 so that the precompensation control is performed by the controller 50 in the first delay line 25.

The second switch connects the input of the amplifier 70 to the multi-path unit 60 through the third delay line 61 at the output of the carrier canceler 27 so that the amplifier 70 performs the main amplification function. Switch it on.

Now look at the detailed operation is as follows.

First, the input carrier main signal is divided into an RF signal from the first signal separator 21 to the main amplifier 23 and a signal to the first switch 40. The signal passing through the first switch 40 is input to the controller 50.

The controller 50 receives the final RF output as another input to compensate for the magnitude distortion component and the phase distortion component, two predistorter control signals, that is, a magnitude inverse control signal, Generate a phase inverse control signal.

On the other hand, the RF signal for going to the main amplifier 23, the magnitude reduction, phase adjustment, amplitude adjustment is performed in the first signal adjusting unit 22 and then receives the pre-compensation control signal to be a pre-compensation signal.

In addition, the second signal separation unit 61 in the multi-path unit 60 is divided into an RF signal MAIN RF 1 to the main amplifier 23 and an RF signal MAIN RF 2 to the amplifier 70. .

The MAIN RF 1 signal is amplified by the main amplifier 23 and input to the signal combiner 80 via the second delay line 28.

In addition, the MAIN RF 2 signal is amplified by the amplifier 70 through the second switch 63 via the third delay line 62 in the multi-path unit 60 and is input to the signal combiner 80.

Then, the signal combiner 80 synthesizes the MAIN RF 1 signal and the MAIN RF 2 signal and finally outputs an output signal twice as large as compared with the output of the main amplifier 23.

As such, the present invention adds a pre-compensation function after the maximum rated output in the conventional feedforward LPA, and configures the main amplifier and the error amplifier as a parallel synthesized two-path amplifier using a switch to improve the output by 2 times. You'll double the output without adding one more LPA module.

Although the preferred embodiment of the present invention has been described above, the present invention may use various changes, modifications, and equivalents. It is clear that the present invention can be applied in the same manner by appropriately modifying the above embodiments. Accordingly, the above description does not limit the scope of the invention as defined by the limitations of the following claims.

As described above, the multi-amplification apparatus and method of the linear power amplifier according to the present invention add a pre-compensation function after the maximum rated output in the conventional feedforward LPA, and combine the main amplifier and the error amplifier in parallel by using a switch. By configuring the path amplifier to double the output, it is possible to double the output from a conventional feedforward LPA without adding one more LPA module.

In addition, since the present invention generates twice the output by using one existing LPA, there is an excellent effect in terms of efficiency.

Claims (5)

A signal separating unit for separating an input signal, a first signal adjusting unit for adjusting the main signal separated from the signal separating unit, a main amplifying unit for amplifying the output of the first signal adjusting unit, and a separation of the main amplifying unit A directional coupler, a first delay line for delaying a signal of an error path separated by the signal separation unit, an attenuator for attenuating the output of the directional coupler, an output of the attenuator and an output of the first delay line. A linear power amplifier comprising a carrier canceler for outputting an IMD signal, a second delay line for delaying the output of the directional coupler, and a second signal adjuster for performing signal adjustment on the output of the carrier canceller. , A first switch positioned between the first signal separator and the first delay line to switch a carrier signal to be input to the first delay line or to a controller; Respectively controlling the first and second signal adjusting units to perform a carrier canceller and an IMD canceller, and perform pre-compensation control by receiving an error path signal switched by the first switch and a signal output from the signal combiner A controller; A multipath unit coupled between the main path and the error path separated by the first signal separator to perform parallel synthesized multipath amplification; An amplifying unit positioned at a next stage of the multi-path unit to perform an error amplifying function up to a maximum rated output, and performing a main amplifying function above the maximum rated output; Multi-linear power amplifier comprising a signal combiner for receiving the output of the second delay line and the amplification unit to perform an IMD canceller function up to the maximum rated output, and to perform a power combining function above the maximum rated output Amplification device. The method of claim 1, wherein the multi path unit, A second signal separation unit located at a next stage of the first signal adjustment unit to separate a signal; A third delay line configured to receive and delay the signal separated by the second signal separator; And a second switch configured to receive the signal of the third delay line and the signal of the second signal adjusting unit and be input to the amplifier by switching. The method of claim 1, wherein the control unit, If the magnitude of the output signal is within the maximum rated output, the first and second signal adjusting unit controls to perform linear power amplification by the feed forward control, and if the magnitude of the output signal is not within the maximum rated output, the first and second And performing a linear power amplification by precompensation control with respect to the second signal adjusting unit. The method according to any one of claims 1 to 3, wherein the control unit, In order to compensate the magnitude distortion component and the phase distortion component by receiving the final RF output as another input, a linear inverted control signal and a phase inverse control signal are generated to control pre-compensation. Multi amplification device. A first step of determining whether the magnitude of the output signal is within a maximum rated output; A second step of performing linear power amplification with feedforward control if the magnitude of the output signal is within the maximum rated output; And a third step of performing linear power amplification by pre-compensation control if the magnitude of the output signal is not within the maximum rated output.

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