JP6665565B2 - Power amplifier - Google Patents

Description

The present invention relates to power amplification equipment of the envelope tracking scheme.

  An envelope tracking method (ET method) is used for a high-frequency amplifier in a power amplifier (PA) of a transmitter in order to increase the power efficiency. In this method, an envelope (envelope: a line connecting the peaks of the waveform of a modulation signal) signal is generated from a baseband input transmission signal, and a power supply voltage to be supplied to a high-frequency amplifier based on the envelope signal is RF (Radio). By controlling according to the envelope of the high frequency (RF) signal, the power consumption is suppressed, and the power added efficiency (PAE) of the high frequency amplifier is consumed by the high frequency signal power generated by the high frequency amplifier. It represents the ratio of DC power, and if the output power is the same, the higher the power addition efficiency, the lower the power consumption.)

In this envelope tracking type power amplifier, the phase of a transmission signal (RF signal) to be amplified input to the high frequency amplifier and the phase of a control power supply voltage generated based on the envelope signal and applied to the high frequency amplifier are described. If the phase shifts, the power supply voltage corresponding to the amplitude of the transmission signal (RF signal) is not supplied, and the transmission signal output from the high-frequency amplifier is distorted. Therefore, it is important that the phases do not shift.
This phase shift depends on the electrical length of the electric circuit (the length of the wiring is expressed based on the wavelength of the electric signal in the wiring) and the characteristics of the electronic component until the input transmission signal is input to the high-frequency amplifier. Generates an envelope signal from a transmission signal, generates a control power supply voltage for the high-frequency amplifier based on the envelope signal, and supplies it to the high-frequency amplifier. It is. For this reason, a circuit is designed so that a phase shift does not occur, and a certain margin is given to the value of the control power supply voltage in anticipation of a certain phase shift.

  Actually, the phase shift occurs between the input transmission signal input to the high-frequency amplifier and the applied control power supply voltage due to variations in individual circuits including electronic components, changes in operating temperature, aging, etc. There has been proposed a technique for automatically adjusting the phase of a transmission signal and a control power supply voltage automatically using a test signal periodically (for example, see Patent Document 1).

International Publication No. 2011/125261

However, in this prior art, when performing phase adjustment, the phase between the transmission signal and the control power supply voltage is adjusted using the test signal, so that the phase cannot be adjusted during transmission. Therefore, when a phase shift occurs during transmission, it cannot be corrected. Therefore, considering the phase shift during transmission, the margin of the control power supply voltage cannot be reduced, and the power added efficiency (PAE) of the high-frequency amplifier cannot be reduced. There was a problem that sufficient improvement in power efficiency could not be expected.
Therefore, the present invention has been made in view of the problems of the prior art, and it has been made possible to adjust the phase between a transmission signal and a control power supply voltage during transmission without using a test signal, thereby providing a margin for the control power supply voltage. are intended to be reduced to provide a can be reduced power amplification equipment improvements in power added efficiency (PAE).

  The power amplification device according to one aspect of the present invention is a power amplification device of an envelope tracking system, and includes an input envelope signal generation unit that generates an input envelope signal from a baseband input transmission signal, and an input transmission signal and an input envelope signal. A phase adjustment unit that adjusts one of the phases and outputs the transmission signal and the envelope signal, an envelope signal processing unit that amplifies the amplitude of the envelope signal to generate a control power supply voltage, and an RF signal from the transmission signal. And a transmission signal processing unit for generating an output transmission signal by amplifying the signal level of the RF signal using the control power supply voltage as a power supply voltage. The phase adjuster adjusts one of the input transmission signal and the input envelope signal so that the phase of the RF signal matches the phase of the control power supply voltage. When the phase of the RF signal matches the phase of the control power supply voltage, Then, an adjustment completion notification is output to the input envelope signal generation unit. The input envelope signal generation unit generates an input envelope signal having a predetermined margin with respect to the input envelope signal generated based on the input transmission signal until receiving the adjustment completion notification, and performs a predetermined process after receiving the adjustment completion notification. To generate an envelope signal with a reduced margin.

  According to one embodiment of the present invention, the phase is adjusted so that the phase of the RF signal input to the high-frequency amplifier during transmission matches the phase of the control power supply voltage, so that the margin of the control power supply voltage can be reduced and the power amplification can be performed. The power added efficiency (PAE) of the device can be improved.

FIG. 1 is a block diagram illustrating a configuration example of a power amplification device according to a first embodiment of the present invention. 5 is a flowchart illustrating a flow of a process of phase adjustment and envelope signal generation by the power amplifying device according to the first embodiment of the present invention. FIG. 9 is a diagram illustrating an example of a waveform of an envelope signal according to the related art. FIG. 3 is a diagram illustrating an example of a waveform of an envelope signal according to the first embodiment of the present invention. It is a block diagram showing an example of composition of a power amplifier concerning a 2nd embodiment of the present invention. It is a flowchart which shows an example of the distortion suppression processing procedure performed in the phase adjustment part in the power amplifier which concerns on 2nd Embodiment of this invention.

Next, an embodiment of the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings are schematic and different from actual ones. Therefore, specific components should be determined in consideration of the following description.
The embodiments described below exemplify apparatuses and methods for embodying the technical idea of the present invention, and the technical idea of the present invention describes the shape, structure, arrangement, and the like of the components. It is not specified below. The technical idea of the present invention can be variously modified within the technical scope defined by the claims described in the claims.
In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of one embodiment of the present invention. It will be apparent, however, that one or more embodiments may be practiced without these specific details. In other instances, well-known structures and devices are schematically illustrated in order to simplify the drawings.

<First embodiment>
Hereinafter, the power amplifying device according to the first embodiment of the present invention will be described.
(System configuration)
As shown in FIG. 1, a power amplifying device 10 according to the first embodiment includes a transmission signal generation unit 1, an input envelope signal generation unit 2, a phase adjustment unit 3, an envelope signal processing unit 4, a transmission signal processing unit It includes a unit 5, a correlation detection processing unit 6, and a distortion detection processing unit 7.
The transmission signal generation unit 1 generates an input transmission signal SIT that is a baseband digital signal, and outputs the generated input transmission signal SIT to the input envelope signal generation unit 2 and the phase adjustment unit 3. Note that the transmission signal generator 1 may be provided outside the power amplifying device 10 according to the first embodiment. That is, the transmission signal may be an input signal from outside the power amplifying device 10 according to the first embodiment. In this case, the power amplifying device 10 according to the first embodiment only needs to have an input unit for connecting to the external transmission signal generation unit 1.

The input envelope signal generation unit 2 generates an input envelope signal SIE based on the input transmission signal SIT from the transmission signal generation unit 1.
At this time, at the start of transmission, the input envelope signal generation unit 2 adds a predetermined margin to the amplitude of the envelope signal generated based on the input transmission signal SIT until receiving the adjustment completion notification SAC from the phase adjustment unit 3 described later. An added input envelope signal SIE is generated, and this is set as a second input envelope signal SIE2.
The predetermined margin corresponds to the phase of the RF signal SRF based on the input transmission signal SIT to be amplified, which is input to the high frequency amplifier, and the phase of the control power supply voltage VCP generated based on the envelope signal and applied to the high frequency amplifier. The voltage margin is taken into account so that the phase is not shifted when the phase is adjusted by the phase adjuster 3 described later so that the control power supply voltage does not become insufficient.

Further, after receiving the adjustment completion notification SAC from the phase adjustment unit 3, the input envelope signal generation unit 2 reduces the minimum margin obtained by reducing the predetermined margin added to the amplitude of the envelope signal (the distortion described below including zero becomes worse). (To the previous value) to generate an input envelope signal, which is referred to as a first input envelope signal SIE1.
For example, after receiving the adjustment completion notification SAC from the phase adjustment unit 3, the input envelope signal generation unit 2 determines a required adjacent channel leakage power ratio based on a distortion detection signal from a distortion detection processing unit 7 described later. (ACPR: Adjacent Channel Leakage Power Ratio), and generates a first input envelope signal SIE1 that improves power added efficiency (PAE). Then, the input envelope signal generation unit 2 outputs the generated first input envelope signal SIE1 or the second input envelope signal SIE2 to the phase adjustment unit 3.

The phase adjustment unit 3 adjusts the phase of the input transmission signal input from the transmission signal generation unit 1 to output the transmission signal to the transmission signal processing unit 5, and outputs the first input signal from the input envelope signal generation unit 2. A process of adjusting the phase of the input envelope signal SIE1 or the second input envelope signal SIE2 and outputting the first envelope signal SE1 or the second envelope signal SE2 to the envelope signal processing unit 4 is executed.
The phase adjustment unit 3 adjusts the phase of the RF signal SRF input to the high-frequency amplifier 5d described later and the phase of the control power supply voltage VCP so as to eliminate a phase shift, and thereby, a correlation value CV notified from a correlation detection processing unit 6 described later. Is adjusted to the maximum value, the phase of the input transmission signal SIT and the phase of the first input envelope signal SIE1 or the second input envelope signal SIE2 is adjusted as described below.

When the correlation value CV notified from the correlation detection processing unit 6 reaches the maximum value, the phase adjustment unit 3 determines that the phase of the RF signal SRF matches the phase of the control power supply voltage VCP, completes the phase adjustment, and notifies the adjustment completion. The SAC is output to the input envelope signal generator 2.
The envelope signal processing unit 4 amplifies the first envelope signal SE1 or the second envelope signal SE2 from the phase adjustment unit 3 to generate a control power supply voltage VCP, and transmits the control power supply voltage VCP to the transmission signal processing unit 5 and Output to the correlation detection processing unit 6. Note that the control power supply voltage based on the first envelope signal SE1 is distinguished as the first control power supply voltage VCP1, and the control power supply voltage based on the second envelope signal SE2 is distinguished as the second control power supply voltage VCP2.

Here, as an example, the envelope signal processing unit 4 includes a D / A converter (hereinafter, referred to as DAC) 4a, a low-pass filter (hereinafter, referred to as LPF) 4b, an amplifier 4c, and a DC power supply 4d.
The DAC 4a converts the first envelope signal SE1 or the second envelope signal SE2 from the phase adjuster 3 from a digital signal to an analog signal and outputs the analog signal to the LPF 4b at the subsequent stage. The LPF 4b attenuates components having a frequency higher than the cutoff frequency with respect to the envelope signal from the DAC 4a, and outputs the resulting signal to the subsequent amplifier 4c.

The amplifier 4c operates in response to the DC voltage supplied from the DC power supply 4d, amplifies the first envelope signal SE1 or the second envelope signal SE2 from the LPF 4b, and generates the first or second control power supply voltage. Then, it outputs the first control power supply voltage VCP1 or the second control power supply voltage VCP2 to the transmission signal processing unit 5 and the correlation detection processing unit 6.
The DC power supply 4d is a DC power supply such as a battery. Note that the DC power supply 4d may be provided outside the power amplifying device 10 according to the first embodiment. In this case, the power amplifying device 10 according to the first embodiment may have a power input unit for connecting to the external DC power supply 4d.

The transmission signal processing unit 5 receives an oscillation signal from the oscillator 8 described later, converts an input transmission signal from the phase adjustment unit 3 into an RF (Radio Frequency) signal SRF, and converts the RF signal SRF into envelope signal processing. A high-frequency amplifier to which the first control power supply voltage VCP1 or the second control power supply voltage VCP2 from the unit 4 is applied generates an output transmission signal, and the output transmission signal is transmitted to the distortion detection processing unit 7 and the antenna 9 Output.
Here, as an example, the transmission signal processing unit 5 includes a DAC 5a, an LPF 5b, a mixer 5c, and a high-frequency amplifier 5d.

  The DAC 5a converts the transmission signal ST from the phase adjustment unit 3 from a digital signal to an analog signal, and outputs the analog signal to the LPF 5b at the subsequent stage. The LPF 5b attenuates a component having a frequency higher than a cutoff frequency with respect to the analog transmission signal from the DAC 5a, and outputs the signal to the mixer 5c at the subsequent stage. The mixer 5c receives the analog transmission signal from the LPF 5b and the oscillation signal from the oscillator 8, and up-converts the frequency of the analog transmission signal to a high frequency in an RF band (for example, a 260 MHz to 270 MHz band) to generate an RF signal SRF. Then, the RF signal SRF is output to the subsequent high-frequency amplifier 5d.

  The high-frequency amplifier 5d includes, for example, an N-channel field effect transistor (FET), and applies the first control power supply voltage VCP1 or the second control power supply voltage VCP2 output from the envelope signal processing unit 4 to a drain electrode. I do. In particular, when the first control power supply voltage VCP1 with a predetermined margin reduced is applied, the RF signal SRF output from the mixer 5c is amplified with high efficiency by operating near the saturation power point of the high-frequency amplifier 5d. To generate an output transmission signal SOT. Then, the high-frequency amplifier 5d outputs the output transmission signal SOT to the distortion detection processing unit 7 and the antenna 9.

The correlation detection processing unit 6 detects a correlation value between a waveform of the second control power supply voltage VCP2 from the envelope signal processing unit 4 and a signal waveform of the RF signal SRF from the transmission signal processing unit 5, and detects the signal waveform. The correlation value CV is notified to the phase adjustment unit 3.
Here, as an example, the correlation detection processing unit 6 includes an envelope detection unit 6a, an A / D converter (hereinafter, referred to as ADC) 6b, an ADC 6c, and a correlation detection unit 6d.
The envelope detector 6a receives the RF signal SRF output from the mixer 5c of the transmission signal processor 5, detects the RF signal SRF, and generates an envelope (envelope) signal SED. Then, the envelope detector 6a outputs the generated envelope signal SED to the ADC 6b at the subsequent stage. That is, the envelope detector 6a detects the high-frequency RF signal SRF from the mixer 5c and outputs an envelope signal SED.

The ADC 6b converts the envelope signal SED from the envelope detector 6a from an analog signal to a digital signal and outputs the digital signal to the subsequent correlation detector 6d. The ADC 6c converts the second control power supply voltage VCP2 from the amplifier 4c of the envelope signal processing unit 4 from an analog signal to a digital signal, and outputs the digital signal to the correlation detection unit 6d at the subsequent stage.
The correlation detection unit 6d detects a correlation between the envelope signal SED from the ADC 6b and the signal waveform of the second control power supply voltage VCP2 from the ADC 6c, and outputs a correlation value CV of the signal waveform to the phase adjustment unit 3. For example, the correlation detection unit 6d captures the signal waveform of the envelope signal SED from the ADC 6b and the signal waveform of the second control power supply voltage VCP2 from the ADC 6c, and calculates the correlation between the peak values of these two signal waveforms, for example. Then, a correlation value CV indicating the degree of coincidence between the envelope signal SED and the peak value of the second control power supply voltage VCP2 is output to the phase adjustment unit 3.

The distortion detection processing unit 7 receives an oscillation signal from the oscillator 8 described later, converts the output transmission signal SOT from the transmission signal processing unit 5 into a baseband signal, and detects distortion of the signal waveform of the baseband signal. , And outputs the detected distortion value to the input envelope signal generation unit 2.
Here, as an example, the distortion detection processing unit 7 includes a mixer 7a, an LPF 7b, an ADC 7c, and a distortion detection unit 7d.
The mixer 7a receives the oscillation signal from the oscillator 8 and the output transmission signal SOT from the high-frequency amplifier 5d, down-converts the frequency of the output transmission signal SOT to generate a baseband signal, and converts the baseband signal to a subsequent stage. Output to LPF 7b. The LPF 7b attenuates a component having a frequency higher than a cutoff frequency with respect to the baseband signal from the mixer 7a, and outputs the result to the ADC 7c at the subsequent stage. The ADC 7c converts the baseband signal from the LPF 7b from an analog signal to a digital signal, and outputs the digital signal to the distortion detector 7d at the subsequent stage.
The distortion detection unit 7d performs a fast Fourier transform (FFT) on the baseband signal from the ADC 7c, and places it near the frequency of an adjacent channel in the baseband signal (for example, 6.25 kHz when the channel interval is 6.25 kHz). An adjacent channel leakage power ratio (ACPR) indicating distortion of the appearing waveform is detected as a distortion detection value, and the distortion detection value (ACPR) is output to the input envelope signal generation unit 2.

The oscillator 8 generates an oscillation signal having a constant frequency, and outputs the generated oscillation signal to the transmission signal processing unit 5 and the distortion detection processing unit 7. Note that the oscillator 8 may be provided outside the power amplifying device 10 according to the first embodiment. In this case, the power amplifying device 10 according to the first embodiment may have an input unit for connecting to the external oscillator 8.
The antenna 9 radiates an output transmission signal SOT from the transmission signal processing unit 5 to a space as a radio wave (electromagnetic wave) to transmit the output transmission signal SOT to the outside of the power amplification device 10 according to the first embodiment. It is. Note that the antenna 9 may be provided outside the power amplifying device 10 according to the first embodiment. In this case, the power amplifying device 10 according to the first embodiment only needs to have an output unit for connecting to the external antenna 9.

(Phase adjustment and envelope signal generation processing)
Next, the power amplifying device 10 according to the first embodiment adjusts the phase of the RF signal SRF input to the high-frequency amplifier 5d at the start of transmission and the phase of the second control power supply voltage VCP2, and generates an envelope signal. The process flow will be described with reference to FIG.
The transmission signal generation unit 1 generates a baseband input transmission signal SIT, and outputs the generated input transmission signal SIT to the input envelope signal generation unit 2 and the phase adjustment unit 3 (Step S101).

  At the start of transmission, the input envelope signal generation unit 2 does not receive the adjustment completion notification SAC from the phase adjustment unit 3 (No in step S102). As shown in FIG. 3, the control power supply voltage of the high-frequency amplifier 5d needs to have a voltage margin with respect to the transmission signal so that the voltage does not become insufficient, and the input transmission signal SIT is also required to have this voltage margin. And generates a second input envelope signal SIE2 obtained by adding a predetermined margin to the amplitude of the generated envelope signal, and outputs it to the phase adjustment unit 3 (step S103).

The phase adjustment unit 3 outputs the transmission signal ST to the transmission signal processing unit 5 without adjusting the phase because the notification of the correlation value CV is not received from the correlation detection processing unit 6 at the start of transmission, and the second envelope signal SE2 is output to the envelope signal processing unit 4 (step S104).
The envelope signal processing unit 4 generates a second control power supply voltage VCP2 based on the second envelope signal SE2 from the phase adjustment unit 3 (Step S105).
The transmission signal processing unit 5 generates an RF signal SRF from the transmission signal ST from the phase adjustment unit 3 (Step S106).

The correlation detection processing unit 6 detects a correlation value CV between the waveform of the second control power supply voltage VCP2 from the envelope signal processing unit 4 and the waveform of the RF signal SRF from the transmission signal processing unit 5, and calculates the correlation value CV. Output to the phase adjustment unit 3 (step S107).
When receiving the notification of the correlation value CV from the correlation detection processing unit 6, the phase adjustment unit 3 determines whether the correlation value CV is the maximum value (Step S108). In order to determine whether the correlation value CV is the maximum value, the last correlation value CVn-1 is compared with the current correlation value CVn, and when the current correlation value CVn is larger than the previous correlation value CVn-1. If (CVn> CVn-1), the phase is adjusted again without judging the maximum value. If the current correlation value is smaller than the previous correlation value CVn-1 (CVn <CVn-1), the previous phase adjustment is performed. Is determined to be the maximum value of the correlation value CV, and the envelope signal SE and the transmission signal ST from the previous phase adjustment are output.

If it is determined that the correlation value is not the maximum value (No in step S108), the phase of one of the input transmission signal SIT and the second input envelope signal SIE2 is adjusted so that the correlation value becomes the maximum value. (Step S109). Here, the phase adjustment unit 3 sets the phase of the input transmission signal SIT and the second input envelope signal SIE2 such that the correlation value CV between the signal waveforms of the input transmission signal SIT and the second input envelope signal SIE2 is maximized. The leading phase is delayed and adjusted.
Then, the phase adjustment unit 3 outputs the transmission signal ST to the transmission signal processing unit 5, outputs the second envelope signal SE2 to the envelope signal processing unit 4, shifts to step S105, and again performs the correlation in step S108. It is determined whether the value CV is the maximum value. In order to determine the phase leading side of the input transmission signal SIT and the second input envelope signal SIE2, it is preferable to adjust the phase when the second correlation value (the current correlation value) is smaller than the first correlation value. Is the lag side, and when it is large, it can be determined to be the advancing side.

When receiving the notification of the correlation value CV from the correlation detection processing unit 6, the phase adjustment unit 3 outputs the phase having the maximum value when the correlation value CV is determined to be the maximum value (Yes in step S108). At the same time, an adjustment completion notification SAC is output to the input envelope signal generation unit 2 (step S110).
After receiving the phase completion notification SAC from the phase adjustment unit 3 (Yes in step S102), the input envelope signal generation unit 2 applies the second control power supply of the high-frequency amplifier 5d to the RF signal SRF as shown in FIG. In order to allow the voltage VCP2 to have a voltage margin, a predetermined margin in the second input envelope signal VCP2 set in step S103 is reduced to output the first input envelope signal SIE2 (step S111). At the time of reduction, the voltage is gradually reduced while observing a distortion detection result (distortion detection value) described later to obtain a voltage margin for the RF signal as shown in FIG.

The input envelope signal generation unit 2 receives a notification of the distortion detection value ACPR after reducing the predetermined margin from the distortion detection processing unit 7 (Step S112).
The input envelope signal generation unit 2 determines whether or not the distortion detection value ACPR from the distortion detection processing unit 7 is equal to or smaller than a predetermined set value that satisfies the required performance (step S113), and is larger than the set value (step S113). If the required performance is not satisfied) (No in step S113), the margin of the first input envelope signal SIE1 is returned to the margin before the previous reduction (step S115), and a series of processing ends.

In addition, when the distortion detection value ACPR from the distortion detection processing unit 7 is equal to or less than the set value (satisfies the required performance) (Yes in step S113), the input envelope signal generation unit 2 generates the first input envelope. It is determined whether there is still a margin that can be reduced in the signal SIE1 (step S114). The determination method is based on whether or not the margin added by the second input envelope signal SIE2 remains. If there is a margin that can be reduced (Yes in step S114), the process returns to step S111 to further reduce the margin of the first input envelope signal SIE1.
Conversely, if there is no margin that can be reduced (No in step S114), the above-described series of processing ends.

(Effects of First Embodiment)
Hereinafter, effects of the first embodiment will be described.
In the conventional method, the control power supply voltage supplied to the high-frequency amplifier based on the envelope signal generated by the input envelope generation unit needs to have a voltage margin with respect to the RF signal, as shown in FIG.
In the first embodiment, the phase is adjusted so that the phase of the RF signal SRF matches the phase of the second control power supply voltage VCP2 in a state where a voltage margin is provided for the second control power supply voltage VCP2 as shown in FIG. When the adjustment is completed after the phases match, the first control power supply voltage VCP1 having a reduced margin can be obtained as shown in FIG. 4, so that a power amplifying device with higher power added efficiency (PAE) is provided. Can be. Therefore, power consumption of a DC power supply such as a battery can be suppressed.

  In the above embodiment, the phase of the input transmission signal to be amplified, which is input to the high-frequency amplifier at the start of transmission, matches the phase of the control power supply voltage generated based on the envelope signal and applied to the high-frequency amplifier. Therefore, the present invention is not limited to the above embodiment. The present invention is not limited to the above-described embodiment, and the correlation detection processing unit 6 is operated at predetermined time intervals to adjust the phase of the phase adjustment unit 3. May be. In this case, when the transmission time is long, the deviation between the RF signal and the control power supply voltage can be compensated during transmission, and power amplification with higher power added efficiency (PAE) can be performed.

<Second embodiment>
Next, a second embodiment of the present invention will be described with reference to FIGS.
In the second embodiment, the distortion of the output transmission signal during transmission is monitored, and the phase of the RF signal to be amplified which is input to the high frequency amplifier when the distortion detection value is equal to or greater than a preset value is set. The phase is adjusted to match the phase of the control power supply voltage generated based on the envelope signal and applied to the high-frequency amplifier.
That is, in the second embodiment, as shown in FIG. 5, an adjustment start signal for starting the phase adjustment is provided from the input envelope signal generation unit 2 to the phase adjustment unit 3 in the configuration of FIG. ing.

In the second embodiment, the phase adjustment unit 3 adjusts the phase of the second input envelope signal SIE2 or the input transmission signal SIT at the start of transmission, as in the first embodiment described above, and generates a distortion detection value during transmission. The ACPR is monitored, and the phase of the second input envelope signal SIE2 or the input transmission signal SIT is adjusted based on the distortion detection value ACPR.
Other configurations are the same as those of the above-described first embodiment, and therefore, portions corresponding to those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted.
The input envelope signal generator 2 executes the distortion suppression processing shown in FIG. 6 every predetermined time.

In the distortion suppression processing, first, the distortion detection value ACPR output from the distortion detection unit 7d of the distortion detection processing unit 7 is read (step S201), and then the distortion detection value is equal to or more than a predetermined set value (for example, -55 dB). Is determined (step S202). Note that the distortion detection value output from the distortion detection unit 7d is an adjacent channel leakage power ratio (ACPR), and a predetermined set value is set to a value that satisfies required performance.
If the distortion detection value ACPR is less than the set value in the determination result of step S202 (No in step S202), the phases of the input transmission signal SIT and the first input envelope signal SIE1 are appropriate, and the output transmission signal It is determined that the distortion of the SOT is suppressed, and the process ends.

  When the distortion detection value ACPR is equal to or greater than the set value in the determination result in step S202 (Yes in step S202), the input envelope signal generation unit 2 notifies the phase adjustment unit 3 of the adjustment start signal SAS for starting the phase adjustment. Then, the process proceeds to step 103 of the flowchart of FIG. 2 to generate a second input envelope signal SIE2 having a predetermined margin (step S103), and as shown in the flowchart of FIG. 2 described above. , The phase of the second input envelope signal SIE2 or the input transmission signal SIT is adjusted, and the phase of the RF signal to be amplified input to the high frequency amplifier 5d and the envelope signal generated based on the envelope signal are transmitted to the high frequency amplifier 5d. The phase of the applied second control power supply voltage VCP2 is made coincident to eliminate distortion deterioration.

(Effects of the Second Embodiment)
According to the second embodiment, during transmission, the input envelope signal generation unit 2 monitors the distortion detection value of the output transmission signal SOT, so that the distortion of the output transmission signal SOT becomes larger than a predetermined set value. In this case, it is possible to execute phase adjustment to suppress distortion of the output transmission signal, to reliably maintain the adjacent channel leakage power ratio (ACPR) below a set value, and to add the power added efficiency (PAE) of the power amplifier. Can always be in an efficient state.
Although the present invention has been described with reference to the specific embodiments, the description is not intended to limit the invention. Other embodiments of the invention, as well as various modifications of the disclosed embodiments, will be apparent to persons skilled in the art upon reference to the description of the invention. Therefore, it is to be understood that the appended claims are intended to cover such modifications and embodiments that fall within the scope and spirit of the present invention.

  DESCRIPTION OF SYMBOLS 1 ... Transmission signal generation part, 2 ... Input envelope signal generation part, 3 ... Phase adjustment part, 4 ... Envelope signal processing part, 4a ... DAC, 4b ... LPF, 4c ... Amplifier, 4d ... DC power supply, 5 ... Transmission signal processing Section, 5a DAC, 5b LPF, 5c mixer, 5d high-frequency amplifier, 6 correlation detection processing section, 6a envelope detection section, 6b, 6c ADC, 6d correlation detection section, 7 distortion detection processing Unit, 7a mixer, 7b LPF, 7c ADC, 7d distortion detector, 8 oscillator, 9 antenna, 10 power amplifier

Claims (5)

An envelope tracking type power amplifying device,
An input envelope signal generation unit that generates an input envelope signal from a baseband input transmission signal,
A phase adjustment unit that adjusts the phase of any one of the input transmission signal and the input envelope signal and outputs the transmission signal and the envelope signal, respectively.
An envelope signal processing unit that amplifies the envelope signal to generate a control power supply voltage;
A transmission signal processing unit that generates an RF signal from the transmission signal and amplifies the RF signal with the control power supply voltage as a power supply voltage to generate an output transmission signal;
With
The phase adjuster adjusts the phase of the input transmission signal or the input envelope signal so that the phase of the RF signal matches the phase of the control power supply voltage, and when the phase of the RF signal matches the phase of the control power supply voltage Outputting an adjustment completion notification to the input envelope signal generation unit,
The input envelope signal generation unit generates an input envelope signal having a predetermined margin with respect to the input envelope signal generated based on the transmission signal until receiving the adjustment completion notification, and receives the adjustment completion notification. After that, the power amplification device generates the input envelope signal with the predetermined margin reduced. An envelope detector for detecting an envelope from the RF signal;
A correlation detection processing unit comprising a correlation detection unit that detects a correlation value between the envelope and the waveform of the control power supply voltage,
The power according to claim 1, wherein the phase adjustment unit adjusts the phase of any one of the input transmission signal and the input envelope signal based on a correlation value from the correlation detection processing unit. Amplifying device.   The said phase adjustment part delays the phase of the signal of the phase leading side of the said input transmission signal and the said input envelope signal so that the correlation value from the said correlation detection processing part may become the largest. The said phase adjustment part is characterized by the above-mentioned. 3. The power amplifying device according to 2. A distortion detection processing unit that detects distortion of a signal waveform of the output transmission signal output from the transmission signal processing unit and outputs a distortion detection value,
The input envelope signal generation unit, after receiving the adjustment completion notification from the phase adjustment unit, based on the distortion detection value from the distortion detection processing unit, after securing the adjacent channel leakage power ratio, the predetermined The power amplification device according to claim 1, wherein the input envelope signal that reduces a margin is generated.   The input envelope signal generation unit receives a distortion detection value from the distortion detection processing unit, and when the distortion detection value is equal to or greater than a predetermined set value, the input so that the distortion detection value is less than the set value. The power amplification device according to claim 4, wherein a phase of a transmission signal or the input envelope signal is adjusted.

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