WO2008012898A1 - Power amplifying apparatus - Google Patents

Power amplifying apparatus Download PDF

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Publication number
WO2008012898A1
WO2008012898A1 PCT/JP2006/314899 JP2006314899W WO2008012898A1 WO 2008012898 A1 WO2008012898 A1 WO 2008012898A1 JP 2006314899 W JP2006314899 W JP 2006314899W WO 2008012898 A1 WO2008012898 A1 WO 2008012898A1
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WO
WIPO (PCT)
Prior art keywords
amplifier
power
bias
value
peak amplifier
Prior art date
Application number
PCT/JP2006/314899
Other languages
French (fr)
Japanese (ja)
Inventor
Shinji Ueda
Original Assignee
Panasonic Corporation
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
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Publication date
Application filed by Panasonic Corporation filed Critical Panasonic Corporation
Priority to PCT/JP2006/314899 priority Critical patent/WO2008012898A1/en
Publication of WO2008012898A1 publication Critical patent/WO2008012898A1/en

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Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F1/00—Details of amplifiers with only discharge tubes, only semiconductor devices or only unspecified devices as amplifying elements
    • H03F1/02—Modifications of amplifiers to raise the efficiency, e.g. gliding Class A stages, use of an auxiliary oscillation
    • H03F1/0205—Modifications of amplifiers to raise the efficiency, e.g. gliding Class A stages, use of an auxiliary oscillation in transistor amplifiers
    • H03F1/0288—Modifications of amplifiers to raise the efficiency, e.g. gliding Class A stages, use of an auxiliary oscillation in transistor amplifiers using a main and one or several auxiliary peaking amplifiers whereby the load is connected to the main amplifier using an impedance inverter, e.g. Doherty amplifiers
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F1/00—Details of amplifiers with only discharge tubes, only semiconductor devices or only unspecified devices as amplifying elements
    • H03F1/02—Modifications of amplifiers to raise the efficiency, e.g. gliding Class A stages, use of an auxiliary oscillation
    • H03F1/04—Modifications of amplifiers to raise the efficiency, e.g. gliding Class A stages, use of an auxiliary oscillation in discharge-tube amplifiers
    • H03F1/06—Modifications of amplifiers to raise the efficiency, e.g. gliding Class A stages, use of an auxiliary oscillation in discharge-tube amplifiers to raise the efficiency of amplifying modulated radio frequency waves; to raise the efficiency of amplifiers acting also as modulators
    • H03F1/07—Doherty-type amplifiers
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F1/00—Details of amplifiers with only discharge tubes, only semiconductor devices or only unspecified devices as amplifying elements
    • H03F1/32—Modifications of amplifiers to reduce non-linear distortion
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F3/00—Amplifiers with only discharge tubes or only semiconductor devices as amplifying elements
    • H03F3/20—Power amplifiers, e.g. Class B amplifiers, Class C amplifiers
    • H03F3/21—Power amplifiers, e.g. Class B amplifiers, Class C amplifiers with semiconductor devices only
    • H03F3/211—Power amplifiers, e.g. Class B amplifiers, Class C amplifiers with semiconductor devices only using a combination of several amplifiers
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F3/00—Amplifiers with only discharge tubes or only semiconductor devices as amplifying elements
    • H03F3/20—Power amplifiers, e.g. Class B amplifiers, Class C amplifiers
    • H03F3/24—Power amplifiers, e.g. Class B amplifiers, Class C amplifiers of transmitter output stages
    • H03F3/245—Power amplifiers, e.g. Class B amplifiers, Class C amplifiers of transmitter output stages with semiconductor devices only

Definitions

  • the present invention relates to a power amplifying apparatus that can be mounted on a multi-carrier portable terminal that transmits and receives multi-carrier signals.
  • a Doherty amplifier is known as a power amplifying apparatus that can amplify even a multicarrier signal having such a high peak power with high efficiency (for example, see Non-Patent Document 1).
  • FIG. 1 is a schematic configuration diagram of a commonly known Dono / Tee amplifier.
  • the Doherty amplifier consists of a splitter 1 that distributes the input RF signal, a carrier amplifier 2, a peak amplifier 3, and a first ⁇ ⁇ 4 transmission line 4 that performs a phase delay of 90 °.
  • the second ⁇ 4 transmission line 5 and the third ⁇ 4 transmission line 6 are used.
  • the load impedance of the carrier amplifier 2 is modulated by the output current of the peak amplifier 3 by the action of the phase delay of 90 ° by the first ⁇ ⁇ 4 transmission line 4 and the second ⁇ ⁇ 4 transmission line 5. .
  • the carrier amplifier 2 in a region where the input power is low, only the carrier amplifier 2 operates in a state where the load impedance is high and operates at a high efficiency, and in a region where the input power is high. Since the load impedance of the carrier amplifier 2 is lowered by the output current of the peak amplifier 3 and the saturation power is raised while maintaining high efficiency, even a signal having high peak power can be amplified with high efficiency. That is, it is possible to perform high-efficiency amplification even in a region where the input power is low even in a region where the input power is high.
  • the carrier amplifier 2 operates with a high load impedance. However, there is a problem that distortion characteristics deteriorate.
  • FIG. 2 is a circuit diagram showing a configuration summarizing the power amplifying device disclosed in Patent Document 1.
  • the circuit configuration of the power amplifier shown in Fig. 2 controls the bias of the first bias control network 7 and the peak amplifier 3 to control the bias of the carrier amplifier 2 in addition to the configuration of the Dono and Tee amplifiers in Fig. 1.
  • the second bias control network 8 is configured.
  • FIG. 3 is a characteristic diagram showing the relationship between output power and efficiency in the power amplifying apparatus shown in FIG. 2, with the horizontal axis representing power and the vertical axis representing efficiency. That is, in the circuit configuration shown in FIG. 2, when the output power of the power amplifying device (that is, the output power of the third ⁇ 4 transmission line 6) is low and the low power mode, the power amplifying device operates as a Doherty amplifier.
  • the second bias control network 8 is controlled so that the power amplifier operates as a balance amplifier (that is, a class amplifier) in the high power mode where the output power of the power amplifier is high. 8 is controlling.
  • the second bias control network 8 controls the peak amplifier 3 to be turned off so that the power amplifier operates as a Doherty amplifier.
  • the bias of the peak amplifier 3 is controlled by the second bias control network 8 so that the power amplifying device operates as a balance amplifier (class AB amplifier).
  • the second bias control network 8 switches the peak amplifier 3 to OFF and ON according to the magnitude of the output power, which is the low power mode or the high power mode.
  • the characteristics as a Doherty amplifier and the characteristics as a class AB amplifier are switched.
  • the second bias control network 8 is connected to the peak amplifier 3. Is turned on (that is, in the high power mode region), increasing the noise and operating as a balance amplifier (Class AB amplifier).
  • the Dono and Tee amplifier characteristics (a) in the region of low output power and low power mode are shown in FIG. As high as In the high power mode region where the output power is high, the efficiency is reduced, but the distortion characteristics are low distortion as in the balanced amplifier characteristics (Class AB amplifier characteristics) (b).
  • Class AB amplifier characteristics Class AB amplifier characteristics
  • the power amplifying device shown in FIG. 2 functions as a balance amplifier (class AB amplifier) in the high power mode region, high-efficiency characteristics cannot be obtained in order to prioritize distortion characteristics.
  • the distortion is low in the high power mode region, the efficiency is lower than that of the Doherty amplifier characteristics (a).
  • FIG. 4 is a circuit diagram showing a configuration summarizing the power amplifying device disclosed in Patent Document 2.
  • a power bra 9 for extracting a signal so as not to reduce the gain of the input RF signal 9 The configuration includes a detector 10 for detecting input power, a first bias control unit 11, and a second bias control unit 12.
  • the active bias is such that the biases of the first bias control unit 11 and the second bias control unit 12 change substantially proportionally as the input power detected by the detector 10 increases.
  • the first bias controller 11 reduces the bias of the carrier amplifier 2 and the second bias. Since the control unit 12 increases the bias of the peak amplifier 3, as shown in the characteristic (c) of Patent Document 2 of the alternate long and short dash line in FIG.
  • the efficiency is low, in the high power mode it is more efficient than the class AB amplifier characteristics (b). In this way, low distortion characteristics can be maintained while maintaining a relatively high efficiency in the range of the low power mode and the high power mode.
  • Patent Document 1 Japanese Unexamined Patent Application Publication No. 2004-173231
  • Patent Document 2 Special Table 2000-513535
  • the detector 10 for detecting the input power the first bias control unit 11 and the second noisy control unit 12. Since the circuit scale becomes large due to the complexity of the configuration and the increase in the number of adjustment points of the analog circuit, such a power amplifier is not available for portable terminals intended for miniaturization. It becomes extremely difficult to implement.
  • the modulation scheme of the multi-carrier signal to be transmitted changes, so that when the peak factor of the multi-carrier signal becomes large, the balance amplifier (AB Even if it operates as a class amplifier), the low distortion characteristics cannot be maintained, and as a result, there is a problem that the distortion in the power amplifying device deteriorates.
  • the peak factor of a multicarrier signal changes, such as switching between R99 and Rel5 in WCDMA (Wideband Code Division Multiple Access) or switching between QPSK (Quadri Phase Shift Keying) and 16QAM (16 Quadrature Amplitude Modulation).
  • An object of the present invention is to provide a high-efficiency and low-distortion power amplifying apparatus that can be applied to a mobile terminal, particularly a multi-carrier mobile terminal.
  • a power amplifying apparatus of the present invention is a power amplifying apparatus that branches an input signal and performs power amplification by a Doherty amplification function using a carrier amplifier and a peak amplifier.
  • the bias voltage control means for controlling the bias voltage or the bias current of the peak amplifier is used. According to such a configuration, the optimum bias voltage corresponding to the output power without using a complicated circuit is increased in peak. Since it can be applied to the width device, a low distortion and high efficiency power amplifier can be easily realized.
  • the balance amplifier (AB) is set by setting the noise value of the peak amplifier so that the distortion characteristic falls below a predetermined threshold.
  • Class amplification This makes it possible to use the TPC setting value of the variable gain amplifier that allows the mobile terminal to perform transmission power control over a high dynamic range, thereby improving efficiency and reducing distortion without adding a complicated circuit. Can be realized.
  • the relationship between the TPC set value and the bias value of the peak amplifier whose distortion characteristic falls below a predetermined threshold is set by the TPC set value.
  • the ACLR characteristics are set to the minimum bias value that is less than the standard value. Therefore, the distortion characteristics can be satisfied and the high-efficiency operation of the Doherty amplifier can be maintained.
  • the power amplifying device of the present invention when the TPC set value is the maximum value, the noise value of the peak amplifier is made equal to or less than the bias value of the carrier amplifier. . Therefore, at the time of maximum output, both the peak amplifier and the carrier amplifier have a configuration close to a balance amplifier as a class AB amplifier, so that the maximum output power can be achieved with low distortion while maintaining a state close to saturation power. In addition, highly efficient operation can be realized. Therefore, the power amplifying apparatus of the present invention can be applied to a portable terminal that can transmit a radio signal with high efficiency and low distortion.
  • FIG. 1 Schematic configuration diagram of commonly known Dono and Tee amplifiers
  • FIG. 2 is a circuit diagram showing a configuration summarizing the power amplifying device disclosed in Patent Document 1.
  • FIG. 3 Characteristic diagram showing the relationship between output power and efficiency in the power amplifying device shown in FIG. 2 ⁇ 4] Circuit diagram showing a configuration summarizing the power amplifying device disclosed in Patent Document 2
  • FIG. 5 is a configuration diagram of a power amplification device applied to Embodiment 1 of the present invention.
  • FIG. 6 is a diagram showing an example of a table stored in the bias value table shown in FIG.
  • FIG. 7 is a characteristic diagram showing the relationship between output power and distortion in the power amplifying apparatus shown in FIG.
  • FIG. 8 is a characteristic diagram showing the relationship between output power and efficiency in the power amplifying apparatus shown in FIG.
  • FIG. 9 is a circuit diagram showing the configuration of the carrier amplifier shown in FIG.
  • FIG. 10 is a circuit diagram showing the configuration of the peak amplifier shown in FIG.
  • FIG. 11 is a configuration diagram of a power amplifying device applied to Embodiment 2 of the present invention.
  • FIG. 12 is a configuration diagram of a power amplifying device applied to Embodiment 3 of the present invention.
  • FIG. 13 is a configuration diagram of a power amplifying device applied to Embodiment 4 of the present invention.
  • the power amplifying apparatus of the present invention obtains a noise value of a peak amplifier that maximizes efficiency while satisfying a desired low distortion condition in advance, and uses the transmission power control set value (TPC set value) to determine the peak amplifier.
  • the bias value is switched. That is, the bias value of the peak amplifier is controlled according to the TPC setting value.
  • the optimum bias value for the peak amplifier can be set according to the output power without using a complicated circuit, so that it can be applied over a wide power range from the low power mode to the high power mode. Therefore, high efficiency and low distortion can be realized.
  • the power amplifying apparatus of the present invention switches the bias value of the peak amplifier using a modulation mode such as a modulation scheme and the number of code multiplexes and a TPC setting value.
  • a modulation mode such as a modulation scheme and the number of code multiplexes and a TPC setting value.
  • a temperature detection unit is provided, and the temperature information detected by the temperature detection unit and the bias value of the TPC set value force peak amplifier are switched. As a result, even when the operating temperature of the power amplification device fluctuates, it is possible to achieve low distortion characteristics while maintaining high efficiency characteristics.
  • FIG. 5 is a configuration diagram of a power amplifying device applied to Embodiment 1 of the present invention.
  • This power amplifying device includes a modulation unit 1 01, frequency converter 102, variable gain amplifier 103, splitter 104, carrier amplifier 105, peak amplifier 106, first ⁇ 4 transmission line 107, second ⁇ 4 transmission line 108, third ⁇ 4 transmission line 109, A transmission power setting unit 110, a delay adjustment unit 111, a bias value table 112, and a bias setting unit (bias voltage control means) 113 are included.
  • the delay adjustment unit 111, the bias value table 112, and the bias setting unit 113 are components added according to the present invention, and other components are the conventional dono and tee amplification. Since these are the components of the power amplifying device realized by the device, description of those components will be made to the minimum necessary.
  • Modulation section 101 has a function for modulating the input baseband signal.
  • the frequency conversion unit 102 has a function of performing RFZIF conversion on the modulated baseband signal.
  • the variable gain amplifier 103 has a function of pre-amplifying the RF signal or IF signal before the Doherty amplifier.
  • the splitter 104 has a function of branching the RF signal or IF signal input to the Doherty amplifier.
  • the configuration subsequent to the splitter 104 is a configuration that realizes the Doherty amplification function, and the carrier amplifier 105 has a low input power and is highly efficient because it operates in a region with a high load impedance. It has a function to operate.
  • the peak amplifier 106 is a signal having a high peak power by raising the saturation power while maintaining high efficiency because the load impedance viewed from the carrier amplifier 105 is lowered by the output current of the peak amplifier 106 in a region where the input power is high. Even if it exists, it has a function to perform highly efficient amplification.
  • the first ⁇ ⁇ 4 transmission line 107, the second ⁇ ⁇ 4 transmission line 108, and the third ⁇ ⁇ 4 transmission line 109 are transmission lines for delaying the phase of the input RF signal by 90 °.
  • Transmission power setting section 110 has a function of switching the bias values of variable gain amplifier 103 and peak amplifier 106 and setting TPC setting values for controlling the gains of these amplifiers to desired values.
  • the delay adjustment unit 111 has a function of adjusting the delay of the signal from the variable gain amplifier 103 to the peak amplifier 106. More specifically, the delay adjustment unit 111 includes a variable gain amplifier 103 ⁇ splitter 104 ⁇ second ⁇ 4 transmission line 108. ⁇ A function of absorbing the delay difference between the delay of the signal up to the peak amplifier 106 and the delay of the signal of the bias circuit from the bias value table 112 ⁇ the bias setting unit 113 ⁇ the peak amplifier 106.
  • the bias value table 112 stores a database indicating the relationship between the TPC setting value set by the transmission power setting unit 110 and the minimum bias setting value of the peak amplifier 106 that satisfies the distortion condition at that time. . That is, it has a function of selecting a bias setting value that can realize high-efficiency operation while satisfying the distortion condition at a desired transmission power, and outputting the selected bias setting value to the noise setting unit 113.
  • FIG. 6 is a diagram showing an example of a table stored in the bias value table 112 shown in FIG.
  • the bias setting unit 113 includes a variable voltage conversion unit (not shown) of the bias circuit of the peak amplifier 106 in order to realize an intended bias value based on the noise setting value output from the bias value table 112. A function for outputting a control signal is provided. A detailed description of the bias value table in FIG. 6 will be described later.
  • the gain of the variable gain amplifier 103 is controlled by the TPC setting value set by the transmission power setting unit 110, and is input to the splitter 104 at the input stage of the Dono / tee amplification function to control the power gain.
  • the information of the TPC set value set by the transmission power setting unit 110 is branched into a system to the variable gain amplifier 103 and a system to the delay adjustment unit 111.
  • the information of the TPC set value input to the system of the delay adjustment unit 111 is subjected to delay adjustment by the delay adjustment unit 111, and then is biased by the bias value tape node 112 which is a bias circuit of the peak amplifier 106. .
  • the bias value table 112 has the highest efficiency while the Doherty amplification function satisfies a desired distortion characteristic under the power condition determined based on the TPC setting value set by the transmission power setting unit 110.
  • the bias value of the peak amplifier 106 is stored. Therefore, when input to the bias setting signal force bias setting unit 113 output from the bias value table 112, the bias setting unit 113 sets the peak amplifier 106 so that the maximum amplification efficiency can be obtained with a desired distortion characteristic. Control the bias.
  • FIG. 7 is a characteristic diagram showing the relationship between output power and distortion in the power amplifying apparatus shown in FIG. 5, with the horizontal axis representing output power and the vertical axis representing distortion. In other words, the characteristics of the four broken lines in FIG.
  • FIG. 7 are the distortion characteristics when the bias of the peak amplifier 106 is switched, and show that the distortion increases along the vertical axis. In other words, the lower the level of the vertical axis, the smaller the distortion (low distortion).
  • FIG. 8 is a characteristic diagram showing the relationship between output power and efficiency in the power amplifying apparatus shown in FIG. 5, with the horizontal axis representing output power and the vertical axis representing efficiency.
  • the distortion characteristic can be improved.
  • the level of distortion remains below the threshold. Note that the output power at points X and Y at which the distortion characteristics at the respective bias values reach the threshold is the linear maximum output power that satisfies the distortion condition.
  • the efficiency of the power amplifier decreases from the high efficiency of the Doherty amplifier in the low power mode to the efficiency of the balance amplifier (Class AB amplifier) in the high power mode. Since the bias value of the peak amplifier 106 is switched step by step so that the level of the current does not exceed the threshold, the efficiency of the Norrance amplifier (class AB amplifier) does not decrease so much. In other words, as shown in Fig. 7, the bias value that maximizes the efficiency should be selected under the condition that the distortion levels a, b, c, d at each bias value are less than the preset threshold. Thus, as shown in Fig.
  • the efficiency is lower than that of the original Doherty amplifier, but the efficiency can be improved as compared with the balance amplifier (Class AB amplifier).
  • the efficiency of the balance amplifier in the high power mode in Fig. 8 is as follows. The efficiency can be made almost constant as shown by the dashed line in the figure.
  • the bias value of the peak amplifier 106 is gradually closer to the balance amplifier (class AB amplifier) so that the distortion level falls below the threshold. Bias control is performed so that In other words, the bias that brings the bias condition of the peak amplifier 106 closer to the bias condition of the carrier amplifier 105 Take control.
  • the high power mode is entered, instead of turning the peak amplifier 106 into a balance amplifier (class AB amplifier) all at once, gradually increasing the bias level of the peak amplifier 106 gradually increases the balance amplifier ( This makes it possible to increase the linear maximum output power while producing the high efficiency characteristics of the Doherty amplification function. As a result, it is possible to achieve a higher efficiency than that of a balanced amplifier, and to achieve a lower back-off than a simple Donotty amplifier.
  • FIG. 9 is a circuit diagram showing a configuration of carrier amplifier 105 shown in FIG.
  • the carrier amplifier 105 includes a transistor 121, an input matching circuit 122 for inputting an RF signal, a gate bias circuit 123 for covering the first gate bias, a power circuit 124 for covering the drain power source, and an output matching circuit 125. Since this is the same as that of the conventional carrier amplifier, its description is omitted.
  • the transistor 121 may be a bipolar transistor such as a force HBT that uses an FET in this example. In that case, the gate bias voltage is the base bias current.
  • FIG. 10 is a circuit diagram showing a configuration of peak amplifier 106 shown in FIG.
  • the peak amplifier 106 in FIG. 10 is different from the carrier amplifier in FIG. 9 in that a variable voltage converter 126 is added to the gate bias circuit 123, and the variable voltage converter 126 is connected to the second gate bias based on the bias control signal.
  • the noise voltage applied to the gate of the transistor 121 is changed by controlling the above.
  • the bias of the peak amplifier 106 is controlled to gradually approach the balance amplifier (class AB amplifier) while keeping the distortion level below the threshold. is doing.
  • the transistor 121 may be a bipolar transistor such as a force HBT that uses an FET in this example. In that case, the gate bias voltage becomes the base bias current.
  • This bias value table includes a TPC setting value set by the transmission power setting unit 110, a noise value biased to the peak amplifier 106, and a bias setting for setting the bias value of the peak amplifier 106 to a desired value.
  • the relationship with values is represented in a table. For example, if the TPC setting value set in the transmission power setting section 110 is negative ( ⁇ 50 to ⁇ lOdBm), the bias value is set to OV. Therefore, the bias setting value in the bias value table 112 is set to 0. That is, the bias supplied from the noise setting unit 113 to the peak amplifier 106 is set to zero, the peak amplifier 106 is turned off, and the carrier amplifier 105 is operated as a Dono / tee amplifier.
  • the bias value table 112 is biased to change the bias value from 0.02 to 0.26 V. Switch the set value in steps from 1 to 13. As a result, the bias level applied from the bias setting unit 113 to the peak amplifier 106 increases stepwise, so that the amplification characteristics of the peak amplifier 106 approach the class AB amplifier of the carrier amplifier 105.
  • the bias set value in the bias value table 112 is fixed to 15 in order to keep the bias value constant at 0.30 V. .
  • the maximum value of the bias value of the peak amplifier 106 is set to be equal to or less than the bias value of the carrier amplifier 105. In other words, when the bias values of the carrier amplifier 105 and the peak amplifier 106 become equal, the entire power amplifying apparatus becomes a balance amplifier.
  • FIG. 11 is a configuration diagram of a power amplifying device applied to Embodiment 2 of the present invention.
  • the difference between the power amplifying device of the second embodiment shown in FIG. 1 and the power amplifying device of the first embodiment shown in FIG. 5 is that a temperature detection unit (temperature detection means) 114 is added to the noise value table 112. This is the point where temperature information is input. Therefore, only the parts different from the power amplifying apparatus of the first embodiment shown in FIG. 5 will be described.
  • temperature detector 114 detects the operating temperature of the power amplifier, and inputs the operating temperature of the power amplifier to bias value table 112 together with the TPC set value set by transmission power setting unit 110.
  • the bias value of the peak amplifier 106 is controlled by the bias setting unit 113 so that the distortion is kept below the threshold value even if the distortion of the power amplifier is caused by the temperature fluctuation.
  • the temperature detection unit 114 detects the operating temperature of the power amplifier and corrects the setting value of the bias value table 112, thereby preventing distortion characteristics from being deteriorated due to temperature fluctuation of the power amplifier.
  • the bias value can be corrected by having the bias value table shown in Fig. 6 for each temperature, and the TPC set value and temperature can be corrected.
  • the bias value can be corrected by obtaining the reference address of the force bias value table. In the latter case, you should have one noise value table.
  • FIG. 12 is a configuration diagram of a power amplifying device applied to Embodiment 3 of the present invention.
  • the power amplifying device of Embodiment 3 shown in FIG. 12 differs from the power amplifying device of Embodiment 1 shown in FIG. 5 in that a power deviation table (between the transmission power setting unit 110 and the variable gain amplifier 103 ( (Power deviation means) 115 is added.
  • the gain of the entire power amplifying device changes, so that the TPC set value is set.
  • the deviation is investigated in advance, and the TPC setting value (that is, the variable gain control installation value) input to the variable gain amplifier 103 is corrected by the power deviation table 115.
  • a power deviation table 115 is provided for changing the gain control setting value of the variable gain amplifier 103 in accordance with the TPC setting value of the transmission power setting unit 110.
  • the power deviation table 115 can adjust the set value of the variable gain amplifier 103 to an optimum value.
  • the bias value table 112 is created after considering the power deviation table 115 in the transmission power setting unit 110, the power deviation table 115 may not be provided separately. The configuration in that case is the same as the configuration in FIG.
  • FIG. 13 is a configuration diagram of a power amplifying device applied to Embodiment 4 of the present invention.
  • the difference between the power amplifying device in the fourth embodiment shown in FIG. 13 and the power amplifying device in the first embodiment shown in FIG. 5 is that the configuration for inputting the modulation method switching signal 116 to the bias value table 112 has been added. Is a point. In other words, if the modulation method changes, the peak factor of the transmission power changes and the distortion characteristics change. Therefore, the modulation method switching signal (modulation method switching information detecting means) 116 The bias value is changed to compensate for the change in distortion characteristics.
  • the power amplifying apparatus of the fourth embodiment inputs the modulation scheme switching signal 116 inputted with the baseband unit power to the bias value table 112 and transmits it by the transmission power setting unit 110 (not shown). Based on the TPC setting value and the modulation system switching signal 116, the bias characteristic of the peak amplifier 106 is switched to compensate for distortion characteristics caused by the peak factor that varies depending on the modulation system.
  • the power amplifier of the present invention can be effectively used for a mobile communication terminal such as a mobile terminal capable of transmitting a radio signal with high efficiency and low distortion.

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Abstract

A power amplifying apparatus that is applicable to a mobile terminal, especially, a mobile terminal of multicarrier system and that exhibits a high efficiency and low distortions. In this power amplifying apparatus, a TPC set value set by a transmission power setting part (110) is subjected to a delay adjustment by a delay adjusting part (111) and then inputted to a bias value table (112) that is a bias circuit of a peak amplifier (106). The bias value table (112) stores such a bias value of the peak amplifier (106) that the power amplifying apparatus exhibits the maximum efficiency, while satisfying a desired distortion characteristic on a power condition decided based on the TPC set value set by the transmission power setting part (110). A bias setting part (113), therefore, controls, based on a bias setting signal from the bias value table (112), the bias of the peak amplifier (106) such that the highest amplifying efficiency can be obtained with the desired distortion characteristic. That is, a Doherty-type amplifier gradually changes into a class AB amplifier.

Description

明 細 書  Specification
電力増幅装置  Power amplifier
技術分野  Technical field
[0001] 本発明は、マルチキャリア信号を送受信するマルチキャリア方式の携帯端末に搭載 可能な電力増幅装置に関する。  TECHNICAL FIELD [0001] The present invention relates to a power amplifying apparatus that can be mounted on a multi-carrier portable terminal that transmits and receives multi-carrier signals.
背景技術  Background art
[0002] 近年、高速無線伝送を実現可能な通信方式として、マルチパスやフェージングに 強いマルチキャリア方式が注目を集めている。このようなマルチキャリア方式では、複 数のキャリア (搬送波）に重畳された送信信号が時間軸上で加算されるため、マルチ キャリア信号に高いピーク電力が生じる。そこで、このような高いピーク電力を有する マルチキャリア信号であっても高効率に増幅を行うことが可能な電力増幅装置として 、ドハティ増幅器が知られている（例えば、非特許文献 1参照)。  In recent years, multi-carrier schemes that are resistant to multipath and fading are attracting attention as communication schemes capable of realizing high-speed wireless transmission. In such a multi-carrier scheme, transmission signals superimposed on a plurality of carriers (carrier waves) are added on the time axis, resulting in high peak power in the multi-carrier signal. Thus, a Doherty amplifier is known as a power amplifying apparatus that can amplify even a multicarrier signal having such a high peak power with high efficiency (for example, see Non-Patent Document 1).
[0003] 図 1は、一般的に知られているドノ、ティ増幅器の概略的な構成図である。図 1に示 すように、ドハティ増幅器は、入力される RF信号を分配するスプリッタ 1、キャリア増幅 器 2、ピーク増幅器 3、及びそれぞれ 90° の位相遅延を行う第一の λ Ζ4伝送線路 4 、第二の λ Ζ4伝送線路 5、第三の λ Ζ4伝送線路 6によって構成されている。このよ うな構成において、第一の λ Ζ4伝送線路 4と第二の λ Ζ4伝送線路 5による 90° の 位相遅延の作用により、ピーク増幅器 3の出力電流によってキャリア増幅器 2の負荷 インピーダンスが変調される。  FIG. 1 is a schematic configuration diagram of a commonly known Dono / Tee amplifier. As shown in Fig. 1, the Doherty amplifier consists of a splitter 1 that distributes the input RF signal, a carrier amplifier 2, a peak amplifier 3, and a first λ Ζ4 transmission line 4 that performs a phase delay of 90 °. The second λ 4 transmission line 5 and the third λ 4 transmission line 6 are used. In such a configuration, the load impedance of the carrier amplifier 2 is modulated by the output current of the peak amplifier 3 by the action of the phase delay of 90 ° by the first λ Ζ4 transmission line 4 and the second λ Ζ4 transmission line 5. .
[0004] 上述のようなドハティ増幅器においては、入力電力が低い領域では、キャリア増幅 器 2のみが負荷インピーダンスの高 、状態で動作するために高効率な動作を行 、、 入力電力が高い領域では、ピーク増幅器 3の出力電流によってキャリア増幅器 2の負 荷インピーダンスが下がり、高効率を維持しながら飽和電力を引き上げるため、高い ピーク電力を有する信号であっても高効率な増幅を行うことができる。つまり、入力電 力が低い領域力も入力電力が高い領域まで高効率な増幅を行うことができる。ところ 力 上述のようなドノ、ティ増幅器においては、キャリア増幅器 2は負荷インピーダンス が高い状態で動作するため、飽和電力が通常の増幅器よりも低くなつて効率が良く なるが歪特性が劣化するという問題がある。 [0004] In the Doherty amplifier as described above, in a region where the input power is low, only the carrier amplifier 2 operates in a state where the load impedance is high and operates at a high efficiency, and in a region where the input power is high. Since the load impedance of the carrier amplifier 2 is lowered by the output current of the peak amplifier 3 and the saturation power is raised while maintaining high efficiency, even a signal having high peak power can be amplified with high efficiency. That is, it is possible to perform high-efficiency amplification even in a region where the input power is low even in a region where the input power is high. However, in the Dono and Tee amplifiers described above, the carrier amplifier 2 operates with a high load impedance. However, there is a problem that distortion characteristics deteriorate.
[0005] そこで、このような歪特性劣化の問題点を解決するために種々の文献が開示されて いる (例えば、特許文献 1、特許文献 2参照)。図 2は、特許文献 1に開示された電力 増幅装置を要約した構成を示す回路図である。図 2に示す電力増幅装置の回路構 成は、図 1のドノ、ティ増幅器の構成にカ卩えて、キャリア増幅器 2のバイアスを制御する 第一バイアス制御ネットワーク 7とピーク増幅器 3のバイアスを制御する第二バイアス 制御ネットワーク 8を有する構成となって 、る。  [0005] Therefore, various documents have been disclosed in order to solve such a problem of distortion characteristic degradation (see, for example, Patent Document 1 and Patent Document 2). FIG. 2 is a circuit diagram showing a configuration summarizing the power amplifying device disclosed in Patent Document 1. In FIG. The circuit configuration of the power amplifier shown in Fig. 2 controls the bias of the first bias control network 7 and the peak amplifier 3 to control the bias of the carrier amplifier 2 in addition to the configuration of the Dono and Tee amplifiers in Fig. 1. The second bias control network 8 is configured.
[0006] また、図 3は、図 2に示す電力増幅装置における出力電力と効率の関係を示す特 性図であり、横軸に電力、縦軸に効率を示している。すなわち、図 2のような回路構成 において、電力増幅装置の出力電力（つまり、第三の λ Ζ4伝送線路 6の出力電力） が低 、低電力モードの場合は、電力増幅装置がドハティ増幅器として動作するように 第二バイアス制御ネットワーク 8を制御し、電力増幅装置の出力電力が高い高電力 モードの場合は電力増幅装置がバランス増幅器 (つまり、 ΑΒ級増幅器)として動作 するように第二バイアス制御ネットワーク 8を制御している。言い換えると、電力増幅 装置の出力電力が低い低電力モードの場合は、電力増幅装置がドハティ増幅装置 として動作するように第二バイアス制御ネットワーク 8によってピーク増幅器 3を OFF にする制御を行い、電力増幅装置の出力電力が高い高電力モードの場合は、電力 増幅装置がバランス増幅器 (AB級増幅器)として動作するように、第二バイアス制御 ネットワーク 8によってピーク増幅器 3のバイアスを制御している。  FIG. 3 is a characteristic diagram showing the relationship between output power and efficiency in the power amplifying apparatus shown in FIG. 2, with the horizontal axis representing power and the vertical axis representing efficiency. That is, in the circuit configuration shown in FIG. 2, when the output power of the power amplifying device (that is, the output power of the third λλ4 transmission line 6) is low and the low power mode, the power amplifying device operates as a Doherty amplifier. The second bias control network 8 is controlled so that the power amplifier operates as a balance amplifier (that is, a class amplifier) in the high power mode where the output power of the power amplifier is high. 8 is controlling. In other words, in the low power mode where the output power of the power amplifier is low, the second bias control network 8 controls the peak amplifier 3 to be turned off so that the power amplifier operates as a Doherty amplifier. In the high power mode where the output power of the device is high, the bias of the peak amplifier 3 is controlled by the second bias control network 8 so that the power amplifying device operates as a balance amplifier (class AB amplifier).
[0007] つまり、図 3に示すように、低電力モードであるか高電力モードであるかという出力 電力の大きさに応じて、第二バイアス制御ネットワーク 8がピーク増幅器 3を OFF及び ONに切り替え制御して、ドハティ増幅器としての特性と AB級増幅器としての特性と を切り替えている。このようにして、ピーク増幅器 3が OFFの領域（つまり、低電力モ ードの領域)でドハティ増幅器の歪特性が閾値（目標値)を越えたら、第二バイアス制 御ネットワーク 8がピーク増幅器 3を ONにして（つまり、高電力モードの領域において )、 ノ ィァスを増カロさせてバランス増幅器 (AB級増幅器）として動作させている。  That is, as shown in FIG. 3, the second bias control network 8 switches the peak amplifier 3 to OFF and ON according to the magnitude of the output power, which is the low power mode or the high power mode. By controlling, the characteristics as a Doherty amplifier and the characteristics as a class AB amplifier are switched. Thus, when the distortion characteristic of the Doherty amplifier exceeds the threshold value (target value) in the region where the peak amplifier 3 is OFF (that is, the region in the low power mode), the second bias control network 8 is connected to the peak amplifier 3. Is turned on (that is, in the high power mode region), increasing the noise and operating as a balance amplifier (Class AB amplifier).
[0008] 従って、特許文献 1に記載された図 2に示すような電力増幅装置では、図 3に示す ように、出力電力の低 、低電力モードの領域ではドノ、ティ増幅器特性 (a)のように高 効率な特性となり、出力電力の高い高電力モードの領域ではバランス増幅器特性 (A B級増幅器特性）（b)のように効率は低下するが低歪な歪特性となる。つまり、図 2に 示す電力増幅装置は、高電力モードの領域ではバランス増幅器 (AB級増幅器)とし て機能するので、歪特性を優先するために高効率な特性が得られず、結果的に、高 電力モードの領域では低歪となるがドハティ増幅器特性 (a)に比べて効率が低下す る。 Therefore, in the power amplifying device shown in FIG. 2 described in Patent Document 1, as shown in FIG. 3, the Dono and Tee amplifier characteristics (a) in the region of low output power and low power mode are shown in FIG. As high as In the high power mode region where the output power is high, the efficiency is reduced, but the distortion characteristics are low distortion as in the balanced amplifier characteristics (Class AB amplifier characteristics) (b). In other words, since the power amplifying device shown in FIG. 2 functions as a balance amplifier (class AB amplifier) in the high power mode region, high-efficiency characteristics cannot be obtained in order to prioritize distortion characteristics. Although the distortion is low in the high power mode region, the efficiency is lower than that of the Doherty amplifier characteristics (a).
[0009] また、ドハティ増幅装置のバイアス回路を制御して歪特性劣化を防止する技術とし て特許文献 2の電力増幅装置が開示されている。図 4は、特許文献 2に開示されてい る電力増幅装置を要約した構成を示す回路図である。図 4に示す電力増幅装置の 回路構成では、図 1のドノ、ティ増幅装置の回路構成に加えて、入力される RF信号の 利得を落とさないように信号を抽出するための力ブラ 9、入力電力を検出するための 検出器 10、第一バイアス制御部 11及び第二バイアス制御部 12を有する構成となつ ている。このような構成によれば、検出器 10で検出された入力電力が大きくなるにつ れて第一バイアス制御部 11と第二バイアス制御部 12のバイアスがほぼ比例して変 化するようなアクティブバイアス回路を実現して 、る。  [0009] Further, a power amplifying apparatus disclosed in Patent Document 2 is disclosed as a technique for preventing distortion characteristic deterioration by controlling a bias circuit of a Doherty amplifying apparatus. FIG. 4 is a circuit diagram showing a configuration summarizing the power amplifying device disclosed in Patent Document 2. In the circuit configuration of the power amplifying device shown in FIG. 4, in addition to the circuit configuration of the Dono and Tee amplifying device in FIG. 1, a power bra 9 for extracting a signal so as not to reduce the gain of the input RF signal 9, The configuration includes a detector 10 for detecting input power, a first bias control unit 11, and a second bias control unit 12. According to such a configuration, the active bias is such that the biases of the first bias control unit 11 and the second bias control unit 12 change substantially proportionally as the input power detected by the detector 10 increases. Implement a bias circuit.
[0010] つまり、特許文献 2に記載の図 4の電力増幅装置では、入力電力が大きくなるにつ れて、第一バイアス制御部 11がキャリア増幅器 2のバイアスを小さくし、かつ第二バイ ァス制御部 12がピーク増幅器 3のバイアスを大きくしているので、図 3の一点鎖線の 特許文献 2の特性 (c)に示すように、低電力モードではドノ、ティ増幅器特性 (a)より効 率が低くなるが、高電力モードでは AB級増幅器特性 (b)より効率が高くなる。このよ うにして、低電力モードと高電力モードの範囲にぉ 、て比較的高 、効率を維持しな がら、低歪な特性を維持することができる。  That is, in the power amplifying device shown in FIG. 4 described in Patent Document 2, as the input power increases, the first bias controller 11 reduces the bias of the carrier amplifier 2 and the second bias. Since the control unit 12 increases the bias of the peak amplifier 3, as shown in the characteristic (c) of Patent Document 2 of the alternate long and short dash line in FIG. Although the efficiency is low, in the high power mode it is more efficient than the class AB amplifier characteristics (b). In this way, low distortion characteristics can be maintained while maintaining a relatively high efficiency in the range of the low power mode and the high power mode.
特干文献 1： RF Power Amplifiers for Wireless Communications , STEVEし. CRIP Special Reference 1: RF Power Amplifiers for Wireless Communications, STEVE. CRIP
PS.Artech House Publishers PS.Artech House Publishers
特許文献 1 :特開 2004— 173231号公報  Patent Document 1: Japanese Unexamined Patent Application Publication No. 2004-173231
特許文献 2 :特表 2000— 513535号公報  Patent Document 2: Special Table 2000-513535
発明の開示  Disclosure of the invention
発明が解決しょうとする課題 [0011] し力しながら、上記の特許文献 1に記載の図 2のような電力増幅装置を携帯端末に 適用する場合は、ダイナミックレンジが広くなるため、使用頻度の高い高電力モード においてはバランス増幅器 (AB級増幅器)となる。つまり、使用頻度の高い高電力モ ードの領域にぉ 、て効率が低下すると 、う不具合が生じる。 Problems to be solved by the invention However, when the power amplifying apparatus as shown in FIG. 2 described in Patent Document 1 described above is applied to a mobile terminal, the dynamic range is widened, so that the balance is maintained in the high power mode that is frequently used. It becomes an amplifier (Class AB amplifier). In other words, when the efficiency decreases in the high power mode area where the frequency of use is high, a malfunction occurs.
[0012] さらに、上記の特許文献 2に記載の図 4のような電力増幅装置では、入力電力を検 出するための検出器 10から第一バイアス制御部 11及び第ニノ ィァス制御部 12まで の構成が複雑になることとアナログ回路の調整箇所が増えることなどが相俟って、回 路規模が大きくなるために、小型化を目的とする携帯端末に対してこのような電力増 幅装置を実装することは極めて困難となる。  Furthermore, in the power amplifying apparatus as shown in FIG. 4 described in Patent Document 2 above, the detector 10 for detecting the input power, the first bias control unit 11 and the second noisy control unit 12. Since the circuit scale becomes large due to the complexity of the configuration and the increase in the number of adjustment points of the analog circuit, such a power amplifier is not available for portable terminals intended for miniaturization. It becomes extremely difficult to implement.
[0013] また、マルチモードの携帯端末では、送信するマルチキャリア信号の変調方式が変 化するため、マルチキャリア信号のピークファクタが大きくなつた場合には、高電力モ ードでバランス増幅器 (AB級増幅器)として動作しても低歪な特性を維持することがで きなくなり、結果的に、電力増幅装置における歪が劣化するという不具合が生じる。 例えば、 WCDMA (Wideband Code Division Multiple Access)における R99と Rel5 の切り替えや、 QPSK (Quadri Phase Shift Keying)と 16QAM (16QuadratureAmplit ude Modulation)の切り替えなどのようにマルチキャリア信号のピークファクタが変わる ような状況においては、低歪を維持することができなくなるので、このような電力増幅 装置をマルチモードの携帯端末に使用することはできない。さらには、携帯端末の環 境温度によって増幅素子の動作領域が変動するため、広い電力範囲に亘つて低歪 な歪特性を維持することができなくなる。  [0013] In addition, in a multi-mode mobile terminal, the modulation scheme of the multi-carrier signal to be transmitted changes, so that when the peak factor of the multi-carrier signal becomes large, the balance amplifier (AB Even if it operates as a class amplifier), the low distortion characteristics cannot be maintained, and as a result, there is a problem that the distortion in the power amplifying device deteriorates. For example, in situations where the peak factor of a multicarrier signal changes, such as switching between R99 and Rel5 in WCDMA (Wideband Code Division Multiple Access) or switching between QPSK (Quadri Phase Shift Keying) and 16QAM (16 Quadrature Amplitude Modulation). Since it is impossible to maintain low distortion, such a power amplifying device cannot be used for a multi-mode portable terminal. Furthermore, since the operating region of the amplifying element varies depending on the ambient temperature of the mobile terminal, it is impossible to maintain low distortion characteristics over a wide power range.
[0014] 本発明は、携帯端末、特にマルチキャリア方式の携帯端末に適用することが可能な 高効率かつ低歪な電力増幅装置を提供することを目的とする。  An object of the present invention is to provide a high-efficiency and low-distortion power amplifying apparatus that can be applied to a mobile terminal, particularly a multi-carrier mobile terminal.
課題を解決するための手段  Means for solving the problem
[0015] 本発明の電力増幅装置は、入力信号を分岐し、キャリア増幅器とピーク増幅器と〖こ よるドハティ増幅機能によって電力増幅を行う電力増幅装置であって、ベースバンド 信号力 抽出された制御信号を用いてピーク増幅器のバイアス電圧またはバイアス 電流を制御するバイアス電圧制御手段を具備する構成を採る。このような構成によれ ば、複雑な回路を用いることなぐ出力電力に応じた最適なバイアス電圧をピーク増 幅器に印加することができるので、低歪かつ高効率な電力増幅装置を容易に実現す ることがでさる。 [0015] A power amplifying apparatus of the present invention is a power amplifying apparatus that branches an input signal and performs power amplification by a Doherty amplification function using a carrier amplifier and a peak amplifier. The bias voltage control means for controlling the bias voltage or the bias current of the peak amplifier is used. According to such a configuration, the optimum bias voltage corresponding to the output power without using a complicated circuit is increased in peak. Since it can be applied to the width device, a low distortion and high efficiency power amplifier can be easily realized.
発明の効果  The invention's effect
[0016] 本発明の電力増幅装置によれば、 TPC設定値に基づいて、歪特性があら力じめ規 定された閾値を下回るようにピーク増幅器のノ ィァス値を設定してバランス増幅 (AB 級増幅）を行っている。これによつて、携帯端末が高ダイナミックレンジに亘つて送信 電力制御を行うための可変利得増幅器の TPC設定値を利用することができるので、 複雑な回路を追加することなく高効率化と低歪化を実現することが可能となる。  [0016] According to the power amplifying device of the present invention, based on the TPC set value, the balance amplifier (AB) is set by setting the noise value of the peak amplifier so that the distortion characteristic falls below a predetermined threshold. Class amplification). This makes it possible to use the TPC setting value of the variable gain amplifier that allows the mobile terminal to perform transmission power control over a high dynamic range, thereby improving efficiency and reducing distortion without adding a complicated circuit. Can be realized.
[0017] また、本発明の電力増幅装置によれば、 TPC設定値と、歪特性があら力じめ規定さ れた閾値を下回るピーク増幅器のバイアス値との関係が、 TPC設定値により設定さ れた送信電力にお 、て、 ACLR特性があら力じめ規定された基準値を下回る最小バ ィァス値となるようになつている。したがって、歪特性を満足させると共にドハティ増幅 器の高効率動作を維持することができる。  [0017] Further, according to the power amplifying device of the present invention, the relationship between the TPC set value and the bias value of the peak amplifier whose distortion characteristic falls below a predetermined threshold is set by the TPC set value. With the transmitted power, the ACLR characteristics are set to the minimum bias value that is less than the standard value. Therefore, the distortion characteristics can be satisfied and the high-efficiency operation of the Doherty amplifier can be maintained.
[0018] また、本発明の電力増幅装置によれば、 TPC設定値が最大値となっている場合は 、ピーク増幅器のノ ィァス値をキャリア増幅器のバイアス値と等しくするかそれ以下に している。したがって、最大出力時においては、ピーク増幅器とキャリア増幅器はい ずれも AB級増幅器としてバランス増幅器に近い構成となるので、低歪で最大出力電 力を実現しながら飽和電力に近 、状態を維持するために高効率動作を実現すること が可能となる。したがって、本発明の電力増幅装置は、高効率かつ低歪で無線信号 を送信することができる携帯端末に適用することが可能となる。  [0018] Further, according to the power amplifying device of the present invention, when the TPC set value is the maximum value, the noise value of the peak amplifier is made equal to or less than the bias value of the carrier amplifier. . Therefore, at the time of maximum output, both the peak amplifier and the carrier amplifier have a configuration close to a balance amplifier as a class AB amplifier, so that the maximum output power can be achieved with low distortion while maintaining a state close to saturation power. In addition, highly efficient operation can be realized. Therefore, the power amplifying apparatus of the present invention can be applied to a portable terminal that can transmit a radio signal with high efficiency and low distortion.
図面の簡単な説明  Brief Description of Drawings
[0019] [図 1]一般的に知られているドノ、ティ増幅器の概略的な構成図 [0019] [Fig. 1] Schematic configuration diagram of commonly known Dono and Tee amplifiers
[図 2]特許文献 1に開示された電力増幅装置を要約した構成を示す回路図  FIG. 2 is a circuit diagram showing a configuration summarizing the power amplifying device disclosed in Patent Document 1.
[図 3]図 2に示す電力増幅装置における出力電力と効率の関係を示す特性図 圆 4]特許文献 2に開示されている電力増幅装置を要約した構成を示す回路図  [FIG. 3] Characteristic diagram showing the relationship between output power and efficiency in the power amplifying device shown in FIG. 2 回路 4] Circuit diagram showing a configuration summarizing the power amplifying device disclosed in Patent Document 2
[図 5]本発明の実施の形態 1に適用される電力増幅装置の構成図  FIG. 5 is a configuration diagram of a power amplification device applied to Embodiment 1 of the present invention.
[図 6]図 5に示すバイアス値テーブルが格納しているテーブルの一例を示す図  6 is a diagram showing an example of a table stored in the bias value table shown in FIG.
[図 7]図 5に示す電力増幅装置における出力電力と歪の関係を示す特性図 [図 8]図 5に示す電力増幅装置における出力電力と効率の関係を示す特性図 FIG. 7 is a characteristic diagram showing the relationship between output power and distortion in the power amplifying apparatus shown in FIG. FIG. 8 is a characteristic diagram showing the relationship between output power and efficiency in the power amplifying apparatus shown in FIG.
[図 9]図 5に示すキャリア増幅器の構成を示す回路図  FIG. 9 is a circuit diagram showing the configuration of the carrier amplifier shown in FIG.
[図 10]図 5に示すピーク増幅器の構成を示す回路図  FIG. 10 is a circuit diagram showing the configuration of the peak amplifier shown in FIG.
[図 11]本発明の実施の形態 2に適用される電力増幅装置の構成図  FIG. 11 is a configuration diagram of a power amplifying device applied to Embodiment 2 of the present invention.
[図 12]本発明の実施の形態 3に適用される電力増幅装置の構成図  FIG. 12 is a configuration diagram of a power amplifying device applied to Embodiment 3 of the present invention.
[図 13]本発明の実施の形態 4に適用される電力増幅装置の構成図  FIG. 13 is a configuration diagram of a power amplifying device applied to Embodiment 4 of the present invention.
発明を実施するための最良の形態  BEST MODE FOR CARRYING OUT THE INVENTION
[0020] 〈発明の概要〉  <Overview of the invention>
本発明の電力増幅装置は、あらかじめ所望の低歪条件を満たしながら効率が最大 となるようなピーク増幅器のノ ィァス値を求めておき、送信電力制御設定値 (TPC設 定値)を用いてピーク増幅器のバイアス値を切り替えている。つまり、 TPC設定値に 応じてピーク増幅器のバイアス値を制御している。これによつて、複雑な回路を用い ることなく出力電力に応じてピーク増幅器への最適なバイアス値を設定することがで きるので、低電力モードから高電力モードまでの広範囲な電力領域に亘つて高効率 かつ低歪を実現することができる。  The power amplifying apparatus of the present invention obtains a noise value of a peak amplifier that maximizes efficiency while satisfying a desired low distortion condition in advance, and uses the transmission power control set value (TPC set value) to determine the peak amplifier. The bias value is switched. That is, the bias value of the peak amplifier is controlled according to the TPC setting value. As a result, the optimum bias value for the peak amplifier can be set according to the output power without using a complicated circuit, so that it can be applied over a wide power range from the low power mode to the high power mode. Therefore, high efficiency and low distortion can be realized.
[0021] また、本発明の電力増幅装置は、変調方式やコード多重数などの変調モードと TP C設定値とを用いてピーク増幅器のバイアス値を切り替えている。これによつて、マル チキャリア信号などのようにピークファクタの大き 、信号に対しても高効率特性を維持 しながら低歪な歪特性を実現することができる。さらには、温度検出部を備えていて、 その温度検出部が検出した温度情報と TPC設定値力 ピーク増幅器のバイアス値を 切り替えている。これによつて、電力増幅装置の動作温度に変動が生じても、高効率 特性を維持しながら低歪な歪特性を実現することができる。  [0021] In addition, the power amplifying apparatus of the present invention switches the bias value of the peak amplifier using a modulation mode such as a modulation scheme and the number of code multiplexes and a TPC setting value. As a result, it is possible to realize distortion characteristics with low distortion while maintaining high efficiency characteristics with respect to a signal having a large peak factor such as a multicarrier signal. Furthermore, a temperature detection unit is provided, and the temperature information detected by the temperature detection unit and the bias value of the TPC set value force peak amplifier are switched. As a result, even when the operating temperature of the power amplification device fluctuates, it is possible to achieve low distortion characteristics while maintaining high efficiency characteristics.
[0022] 次に、本発明に係る電力増幅装置の具体的な実施の形態の幾つかについて詳細 に説明する。以下、各実施の形態で用いる図面において、同一の構成要素は同一 の符号を付し、かつ重複する説明は可能な限り省略する。  Next, some specific embodiments of the power amplifying device according to the present invention will be described in detail. Hereinafter, in the drawings used in the embodiments, the same components are denoted by the same reference numerals, and redundant description will be omitted as much as possible.
[0023] 〈実施の形態 1〉  <Embodiment 1>
図 5は、本発明の実施の形態 1に適用される電力増幅装置の構成図である。まず、 図 5に示す電力増幅装置の構成について説明する。この電力増幅装置は、変調部 1 01、周波数変換部 102、可変利得増幅器 103、スプリッタ 104、キャリア増幅器 105 、ピーク増幅器 106、第一の λ Ζ4伝送線路 107、第二の λ Ζ4伝送線路 108、第 三の λ Ζ4伝送線路 109、送信電力設定部 110、遅延調整部 111、バイアス値テー ブル 112、及びバイアス設定部 (バイアス電圧制御手段） 113によって構成されてい る。 FIG. 5 is a configuration diagram of a power amplifying device applied to Embodiment 1 of the present invention. First, the configuration of the power amplification device shown in FIG. 5 will be described. This power amplifying device includes a modulation unit 1 01, frequency converter 102, variable gain amplifier 103, splitter 104, carrier amplifier 105, peak amplifier 106, first λλ4 transmission line 107, second λΖ4 transmission line 108, third λλ4 transmission line 109, A transmission power setting unit 110, a delay adjustment unit 111, a bias value table 112, and a bias setting unit (bias voltage control means) 113 are included.
[0024] なお、図 5において、遅延調整部 111、バイアス値テーブル 112、及びバイアス設 定部 113が本発明によって付加された構成要素であり、それ以外の構成要素は従来 のドノ、ティ増幅装置によって実現される電力増幅装置の構成要素であるので、それ らの構成要素の説明は必要最小限に行う。  In FIG. 5, the delay adjustment unit 111, the bias value table 112, and the bias setting unit 113 are components added according to the present invention, and other components are the conventional dono and tee amplification. Since these are the components of the power amplifying device realized by the device, description of those components will be made to the minimum necessary.
[0025] 変調部 101は、入力されたベースバンド信号を変調するための機能を備えている。  [0025] Modulation section 101 has a function for modulating the input baseband signal.
周波数変換部 102は、変調されたベースバンド信号を RFZIF変換する機能を備え ている。可変利得増幅器 103は、 RF信号または IF信号をドハティ増幅装置の前段で プレ増幅する機能を備えている。スプリッタ 104は、ドハティ増幅装置へ入力される R F信号または IF信号を分岐する機能を備えて 、る。  The frequency conversion unit 102 has a function of performing RFZIF conversion on the modulated baseband signal. The variable gain amplifier 103 has a function of pre-amplifying the RF signal or IF signal before the Doherty amplifier. The splitter 104 has a function of branching the RF signal or IF signal input to the Doherty amplifier.
[0026] スプリッタ 104以降の構成がドハティ増幅機能を実現する構成であり、キャリア増幅 器 105は、入力電力が低!、領域にぉ 、て負荷インピーダンスの高 、状態で動作する ために高効率な動作を行う機能を備えている。ピーク増幅器 106は、入力電力の高 い領域において、ピーク増幅器 106の出力電流によってキャリア増幅器 105から見 た負荷インピーダンスが下がるので、高効率を維持しながら飽和電力を引き上げて 高いピーク電力を有する信号であっても高効率な増幅を行う機能を備えている。第 一の λ Ζ4伝送線路 107、第二の λ Ζ4伝送線路 108、及び第三の λ Ζ4伝送線路 109は、それぞれ、入力された RF信号の位相を 90° 遅延させるための伝送線路で ある。  [0026] The configuration subsequent to the splitter 104 is a configuration that realizes the Doherty amplification function, and the carrier amplifier 105 has a low input power and is highly efficient because it operates in a region with a high load impedance. It has a function to operate. The peak amplifier 106 is a signal having a high peak power by raising the saturation power while maintaining high efficiency because the load impedance viewed from the carrier amplifier 105 is lowered by the output current of the peak amplifier 106 in a region where the input power is high. Even if it exists, it has a function to perform highly efficient amplification. The first λ Ζ4 transmission line 107, the second λ Ζ4 transmission line 108, and the third λ Ζ4 transmission line 109 are transmission lines for delaying the phase of the input RF signal by 90 °.
[0027] 送信電力設定部 110は、可変利得増幅器 103及びピーク増幅器 106のバイアス値 を切り替えてそれらの増幅器の利得を制御するための TPC設定値を所望の値に設 定する機能を備えている。遅延調整部 111は、可変利得増幅器 103からピーク増幅 器 106までの信号の遅延を調整する機能を備えている。さらに詳しく述べると、遅延 調整部 111は、可変利得増幅器 103→スプリッタ 104→第二の λ Ζ4伝送線路 108 →ピーク増幅器 106までの信号の遅延と、バイアス値テーブル 112→バイアス設定 部 113→ピーク増幅器 106までのバイアス回路の信号の遅延との遅延差を吸収する 機能を備えている。 [0027] Transmission power setting section 110 has a function of switching the bias values of variable gain amplifier 103 and peak amplifier 106 and setting TPC setting values for controlling the gains of these amplifiers to desired values. . The delay adjustment unit 111 has a function of adjusting the delay of the signal from the variable gain amplifier 103 to the peak amplifier 106. More specifically, the delay adjustment unit 111 includes a variable gain amplifier 103 → splitter 104 → second λΖ4 transmission line 108. → A function of absorbing the delay difference between the delay of the signal up to the peak amplifier 106 and the delay of the signal of the bias circuit from the bias value table 112 → the bias setting unit 113 → the peak amplifier 106.
[0028] バイアス値テーブル 112は、送信電力設定部 110が設定した TPC設定値と、その ときの歪条件を充たすピーク増幅器 106の最小のバイアス設定値との関係を示すデ ータベースを格納している。すなわち、所望の送信電力において、歪条件を充たしつ つ高効率な動作を実現することができるようなバイアス設定値をテーブル力 選択し てノ ィァス設定部 113へ出力する機能を備えている。図 6は、図 5に示すバイアス値 テーブル 112が格納して!/、るテーブルの一例を示す図である。バイアス設定部 113 は、バイアス値テーブル 112から出力されたノ ィァス設定値に基づいて意図したバイ ァス値を実現するために、ピーク増幅器 106のバイアス回路の可変電圧変換部（図 示せず)を制御する信号を出力する機能を備えている。なお、図 6のバイアス値テー ブルの詳細な説明につ 、ては後述する。  [0028] The bias value table 112 stores a database indicating the relationship between the TPC setting value set by the transmission power setting unit 110 and the minimum bias setting value of the peak amplifier 106 that satisfies the distortion condition at that time. . That is, it has a function of selecting a bias setting value that can realize high-efficiency operation while satisfying the distortion condition at a desired transmission power, and outputting the selected bias setting value to the noise setting unit 113. FIG. 6 is a diagram showing an example of a table stored in the bias value table 112 shown in FIG. The bias setting unit 113 includes a variable voltage conversion unit (not shown) of the bias circuit of the peak amplifier 106 in order to realize an intended bias value based on the noise setting value output from the bias value table 112. A function for outputting a control signal is provided. A detailed description of the bias value table in FIG. 6 will be described later.
[0029] 次に、図 5に示す電力増幅装置の動作について説明する力 ドハティ増幅器の動 作は周知の技術であるのでその説明は省略し、本発明に係わる部分を中心に詳しく 説明する。送信電力設定部 110で設定された TPC設定値により可変利得増幅器 10 3の利得が制御され、ドノ、ティ増幅機能の入力段のスプリツタ 104へ入力されて電力 利得が制御される。このとき、送信電力設定部 110で設定された TPC設定値の情報 は、可変利得増幅器 103への系統と遅延調整部 111への系統に分岐される。そして 、遅延調整部 111の系統へ入力された TPC設定値の情報は、遅延調整部 111によ つて遅延調整された後に、ピーク増幅器 106のバイアス回路であるバイアス値テープ ノレ 112〖こ人力される。  Next, the operation of the power Doherty amplifier for explaining the operation of the power amplifying device shown in FIG. 5 is a well-known technique, so that the explanation thereof will be omitted and will be described in detail mainly on the portion related to the present invention. The gain of the variable gain amplifier 103 is controlled by the TPC setting value set by the transmission power setting unit 110, and is input to the splitter 104 at the input stage of the Dono / tee amplification function to control the power gain. At this time, the information of the TPC set value set by the transmission power setting unit 110 is branched into a system to the variable gain amplifier 103 and a system to the delay adjustment unit 111. The information of the TPC set value input to the system of the delay adjustment unit 111 is subjected to delay adjustment by the delay adjustment unit 111, and then is biased by the bias value tape node 112 which is a bias circuit of the peak amplifier 106. .
[0030] このとき、バイアス値テーブル 112には、送信電力設定部 110で設定された TPC設 定値に基づいて決められた電力条件でドハティ増幅機能が所望の歪特性を満足し ながら効率が最も良くなるようなピーク増幅器 106のバイアス値が格納されている。し たがって、バイアス値テーブル 112から出力されたバイアス設定信号力バイアス設定 部 113に入力されると、バイアス設定部 113は、所望の歪特性で最高の増幅効率が 得られるようにピーク増幅器 106のバイアスを制御する。 [0031] 図 7は、図 5に示す電力増幅装置における出力電力と歪の関係を示す特性図であ り、横軸に出力電力、縦軸に歪を示している。つまり、図 7における 4本の破線の特性 がピーク増幅器 106のバイアスを切り替えたときの歪特性であり、縦軸の上に行くにし たがって歪が大きくなることを示している。言い換えれば、縦軸のレベルが低いほど 歪が小さいこと (低歪）を示している。また、図 8は、図 5に示す電力増幅装置における 出力電力と効率の関係を示す特性図であり、横軸に出力電力、縦軸に効率を示して いる。 [0030] At this time, the bias value table 112 has the highest efficiency while the Doherty amplification function satisfies a desired distortion characteristic under the power condition determined based on the TPC setting value set by the transmission power setting unit 110. The bias value of the peak amplifier 106 is stored. Therefore, when input to the bias setting signal force bias setting unit 113 output from the bias value table 112, the bias setting unit 113 sets the peak amplifier 106 so that the maximum amplification efficiency can be obtained with a desired distortion characteristic. Control the bias. FIG. 7 is a characteristic diagram showing the relationship between output power and distortion in the power amplifying apparatus shown in FIG. 5, with the horizontal axis representing output power and the vertical axis representing distortion. In other words, the characteristics of the four broken lines in FIG. 7 are the distortion characteristics when the bias of the peak amplifier 106 is switched, and show that the distortion increases along the vertical axis. In other words, the lower the level of the vertical axis, the smaller the distortion (low distortion). FIG. 8 is a characteristic diagram showing the relationship between output power and efficiency in the power amplifying apparatus shown in FIG. 5, with the horizontal axis representing output power and the vertical axis representing efficiency.
[0032] 図 7に示すように、ピーク増幅器 106のバイアス値を、低電力モードにおけるドノヽテ ィ増幅器力 高電力モードのバランス増幅器に近づくように徐々に切り替えて 、くこと によって、歪特性の各破線のポイント a, b, c, dに示すように、歪のレベルは閾値以 下を保っている。なお、それぞれのバイアス値における歪特性が閾値に達した点 X、 Yの出力電力が歪条件を満足させる線形最大出力電力である。  As shown in FIG. 7, by gradually switching the bias value of the peak amplifier 106 so as to approach the balance amplifier in the high power mode, the distortion characteristic can be improved. As indicated by the dotted points a, b, c, and d, the level of distortion remains below the threshold. Note that the output power at points X and Y at which the distortion characteristics at the respective bias values reach the threshold is the linear maximum output power that satisfies the distortion condition.
[0033] 電力増幅器の効率は、図 8に示すように、低電力モードにおけるドハティ増幅器の 高効率から高電力モードにおけるバランス増幅器 (AB級増幅器)の効率に低下する 力 高電力モードにおいては、歪のレベルが閾値を上回らないようにピーク増幅器 1 06のバイアス値を段階的に切り替えているので、ノランス増幅器 (AB級増幅器)の 効率はそれほど低下しない。つまり、図 7に示すように、各バイアス値における歪のレ ベル a, b, c, dがあら力じめ設定された閾値を下回る条件において、効率が最大とな るバイアス値を選択することにより、図 8に示すように、もともとのドハティ増幅器よりは 効率が低下するが、バランス増幅器 (AB級増幅器)より効率を向上させることができ る。なお、図 8における高電力モードでのバランス増幅器の効率は、図 7のバイアス値 を 4段階に切り替えたのに合わせた特性となっている力 バイアス値の切替点をさら に多くすればバランス増幅器の効率を図の一点鎖線のようにほぼ一定にすることが できる。  [0033] As shown in Fig. 8, the efficiency of the power amplifier decreases from the high efficiency of the Doherty amplifier in the low power mode to the efficiency of the balance amplifier (Class AB amplifier) in the high power mode. Since the bias value of the peak amplifier 106 is switched step by step so that the level of the current does not exceed the threshold, the efficiency of the Norrance amplifier (class AB amplifier) does not decrease so much. In other words, as shown in Fig. 7, the bias value that maximizes the efficiency should be selected under the condition that the distortion levels a, b, c, d at each bias value are less than the preset threshold. Thus, as shown in Fig. 8, the efficiency is lower than that of the original Doherty amplifier, but the efficiency can be improved as compared with the balance amplifier (Class AB amplifier). Note that the efficiency of the balance amplifier in the high power mode in Fig. 8 is as follows. The efficiency can be made almost constant as shown by the dashed line in the figure.
[0034] つまり、バランス増幅器の方が高電力モードの領域では線形性がよくなるので、歪 のレベルが閾値を下回るようにピーク増幅器 106のバイアス値を徐々にバランス増幅 器 (AB級増幅器）に近くなるようにバイアス制御を行う。言い換えると、ピーク増幅器 106のバイアス条件をキャリア増幅器 105のバイアス条件に近付けるようなバイアス 制御を行う。このようにして、高電力モードになったらピーク増幅器 106を一挙にバラ ンス増幅器 (AB級増幅器）にするのではなぐ徐々にピーク増幅器 106のバイアスレ ベルを上げて行くことにより段階的にバランス増幅器 (AB級増幅器）にして、ドハティ 増幅機能の高効率特性を生力しながら線形最大出力電力を大きくすることができる。 これによつて、バランス増幅器よりも高効率ィ匕を実現することができるし、単純なドノ、 ティ増幅器よりも低バックオフ化を図ることができる。 In other words, since the balance amplifier has better linearity in the high power mode region, the bias value of the peak amplifier 106 is gradually closer to the balance amplifier (class AB amplifier) so that the distortion level falls below the threshold. Bias control is performed so that In other words, the bias that brings the bias condition of the peak amplifier 106 closer to the bias condition of the carrier amplifier 105 Take control. In this way, when the high power mode is entered, instead of turning the peak amplifier 106 into a balance amplifier (class AB amplifier) all at once, gradually increasing the bias level of the peak amplifier 106 gradually increases the balance amplifier ( This makes it possible to increase the linear maximum output power while producing the high efficiency characteristics of the Doherty amplification function. As a result, it is possible to achieve a higher efficiency than that of a balanced amplifier, and to achieve a lower back-off than a simple Donotty amplifier.
[0035] 図 9は、図 5に示すキャリア増幅器 105の構成を示す回路図である。このキャリア増 幅器 105は、トランジスタ 121、 RF信号を入力する入力整合回路 122、第一ゲートバ ィァスをカ卩えるゲートバイアス回路 123、ドレイン電源をカ卩える電源回路 124、及び出 力整合回路 125によって構成されていて、従来のキャリア増幅器の構成と同じである のでその説明は省略する。なお、トランジスタ 121は、この例では FETを用いている 力 HBTなどのノイポーラトランジスタを用いてもよい。その場合、ゲートバイアス電 圧はベースバイアス電流となる。  FIG. 9 is a circuit diagram showing a configuration of carrier amplifier 105 shown in FIG. The carrier amplifier 105 includes a transistor 121, an input matching circuit 122 for inputting an RF signal, a gate bias circuit 123 for covering the first gate bias, a power circuit 124 for covering the drain power source, and an output matching circuit 125. Since this is the same as that of the conventional carrier amplifier, its description is omitted. Note that the transistor 121 may be a bipolar transistor such as a force HBT that uses an FET in this example. In that case, the gate bias voltage is the base bias current.
[0036] 図 10は、図 5に示すピーク増幅器 106の構成を示す回路図である。図 10のピーク 増幅器 106が図 9のキャリア増幅器と異なる点は、ゲートバイアス回路 123に可変電 圧変換部 126が追加され、この可変電圧変換部 126が、バイアス制御信号に基づい て第二ゲートバイアスを制御してトランジスタ 121のゲートに印加させるノィァス電圧 を変化させている点である。このようにして、トランジスタ 121のバイアス電圧を変化さ せることにより、歪レベルが閾値を下回るようにキープさせながら、ピーク増幅器 106 のバイアスを徐々にバランス増幅器 (AB級増幅器）に近くなるように制御している。な お、トランジスタ 121は、この例では FETを用いている力 HBTなどのバイポーラトラ ンジスタを用いてもよい。その場合、ゲートバイアス電圧はベースバイアス電流となる  FIG. 10 is a circuit diagram showing a configuration of peak amplifier 106 shown in FIG. The peak amplifier 106 in FIG. 10 is different from the carrier amplifier in FIG. 9 in that a variable voltage converter 126 is added to the gate bias circuit 123, and the variable voltage converter 126 is connected to the second gate bias based on the bias control signal. In other words, the noise voltage applied to the gate of the transistor 121 is changed by controlling the above. In this way, by changing the bias voltage of the transistor 121, the bias of the peak amplifier 106 is controlled to gradually approach the balance amplifier (class AB amplifier) while keeping the distortion level below the threshold. is doing. The transistor 121 may be a bipolar transistor such as a force HBT that uses an FET in this example. In that case, the gate bias voltage becomes the base bias current.
[0037] 再び図 6に戻ってバイアス値テーブルについて詳細に説明する。このバイアス値テ 一ブルは、送信電力設定部 110で設定された TPC設定値と、ピーク増幅器 106にバ ィァスするノィァス値と、ピーク増幅器 106のバイアス値を所望の値に設定するため のバイアス設定値との関係をテーブルにして表わしている。例えば、送信電力設定 部 110で設定された TPC設定値が負の値（― 50〜― lOdBm)ではバイアス値を OV とするためにバイアス値テーブル 112のバイアス設定値を 0とする。つまり、ノィァス 設定部 113からピーク増幅器 106へカ卩えるバイアスをゼロにしてピーク増幅器 106を OFFの状態にし、キャリア増幅器 105をドノ、ティ増幅器として動作させる。 [0037] Returning to Fig. 6 again, the bias value table will be described in detail. This bias value table includes a TPC setting value set by the transmission power setting unit 110, a noise value biased to the peak amplifier 106, and a bias setting for setting the bias value of the peak amplifier 106 to a desired value. The relationship with values is represented in a table. For example, if the TPC setting value set in the transmission power setting section 110 is negative (−50 to −lOdBm), the bias value is set to OV. Therefore, the bias setting value in the bias value table 112 is set to 0. That is, the bias supplied from the noise setting unit 113 to the peak amplifier 106 is set to zero, the peak amplifier 106 is turned off, and the carrier amplifier 105 is operated as a Dono / tee amplifier.
[0038] また、送信電力設定部 110で設定された TPC設定値が正の値で 0〜22dBmまで は、バイアス値を 0. 02〜0. 26Vと変化させるためにバイアス値テーブル 112のバイ ァス設定値を 1〜13と段階的に切り替える。これによつて、バイアス設定部 113からピ ーク増幅器 106へ印加されるバイアスレベルが段階的に増加するので、ピーク増幅 器 106の増幅特性はキャリア増幅器 105の AB級増幅器に近づいて行く。そして、送 信電力設定部 110で設定された TPC設定値が 24dBm以上になったときは、バイァ ス値を 0. 30Vに一定にするためにバイアス値テーブル 112のバイアス設定値を 15 に固定する。つまり、ピーク増幅器 106のバイアス値の最大値はキャリア増幅器 105 のバイアス値以下となるようにする。言い換えると、キャリア増幅器 105とピーク増幅器 106のバイアス値が等しくなつたときに電力増幅装置全体がバランス増幅器となる。  In addition, when the TPC set value set by transmission power setting section 110 is a positive value from 0 to 22 dBm, the bias value table 112 is biased to change the bias value from 0.02 to 0.26 V. Switch the set value in steps from 1 to 13. As a result, the bias level applied from the bias setting unit 113 to the peak amplifier 106 increases stepwise, so that the amplification characteristics of the peak amplifier 106 approach the class AB amplifier of the carrier amplifier 105. When the TPC set value set by the transmission power setting unit 110 becomes 24 dBm or more, the bias set value in the bias value table 112 is fixed to 15 in order to keep the bias value constant at 0.30 V. . That is, the maximum value of the bias value of the peak amplifier 106 is set to be equal to or less than the bias value of the carrier amplifier 105. In other words, when the bias values of the carrier amplifier 105 and the peak amplifier 106 become equal, the entire power amplifying apparatus becomes a balance amplifier.
[0039] 〈実施の形態 2〉  <Embodiment 2>
図 11は、本発明の実施の形態 2に適用される電力増幅装置の構成図である。図 1 1に示す実施の形態 2の電力増幅装置が図 5に示す実施の形態 1の電力増幅装置と 異なる点は、温度検出部（温度検出手段） 114が追加されてノ ィァス値テーブル 112 へ温度情報が入力される点である。したがって、図 5に示す実施の形態 1の電力増幅 装置と異なる部分のみを説明する。  FIG. 11 is a configuration diagram of a power amplifying device applied to Embodiment 2 of the present invention. The difference between the power amplifying device of the second embodiment shown in FIG. 1 and the power amplifying device of the first embodiment shown in FIG. 5 is that a temperature detection unit (temperature detection means) 114 is added to the noise value table 112. This is the point where temperature information is input. Therefore, only the parts different from the power amplifying apparatus of the first embodiment shown in FIG. 5 will be described.
[0040] 図 11において、温度検出部 114が電力増幅器の動作温度を検出し、送信電力設 定部 110で設定された TPC設定値と共に電力増幅器の動作温度をバイアス値テー ブル 112に入力する。これによつて、電力増幅器の温度変動によって歪の劣化が生 じても歪が閾値以下に収まるように、バイアス設定部 113によってピーク増幅器 106 のバイアス値を制御する。  In FIG. 11, temperature detector 114 detects the operating temperature of the power amplifier, and inputs the operating temperature of the power amplifier to bias value table 112 together with the TPC set value set by transmission power setting unit 110. As a result, the bias value of the peak amplifier 106 is controlled by the bias setting unit 113 so that the distortion is kept below the threshold value even if the distortion of the power amplifier is caused by the temperature fluctuation.
[0041] このようにして、温度検出部 114によって電力増幅器の動作温度を検出してバイァ ス値テーブル 112の設定値を補正することにより、電力増幅器の温度変動による歪 特性の劣化を防止することができる。この場合、各温度ごとに図 6に示すバイアス値 テーブルを持つことによってバイアス値を補正することもできるし、 TPC設定値と温度 力 バイアス値テーブルの参照アドレスを求めてバイアス値を補正することもできる。 なお、後者の場合はノ ィァス値テーブルを 1つ持てばょ ヽ。 In this way, the temperature detection unit 114 detects the operating temperature of the power amplifier and corrects the setting value of the bias value table 112, thereby preventing distortion characteristics from being deteriorated due to temperature fluctuation of the power amplifier. Can do. In this case, the bias value can be corrected by having the bias value table shown in Fig. 6 for each temperature, and the TPC set value and temperature can be corrected. The bias value can be corrected by obtaining the reference address of the force bias value table. In the latter case, you should have one noise value table.
[0042] 〈実施の形態 3〉  <Embodiment 3>
図 12は、本発明の実施の形態 3に適用される電力増幅装置の構成図である。図 1 2に示す実施の形態 3の電力増幅装置が図 5に示す実施の形態 1の電力増幅装置と 異なる点は、送信電力設定部 110と可変利得増幅器 103との間に電力偏差テープ ル (電力偏差手段） 115が追加された点である。  FIG. 12 is a configuration diagram of a power amplifying device applied to Embodiment 3 of the present invention. The power amplifying device of Embodiment 3 shown in FIG. 12 differs from the power amplifying device of Embodiment 1 shown in FIG. 5 in that a power deviation table (between the transmission power setting unit 110 and the variable gain amplifier 103 ( (Power deviation means) 115 is added.
[0043] すなわち、送信電力設定部 110で設定された TPC設定値の値に応じてピーク増幅 器 106のバイアスを制御することにより、電力増幅装置全体としての利得が変わるた め、 TPC設定値に基づく電力と変調部 101に入力された RF信号による電力との間 にずれが生じる可能性がある。したがって、あら力じめそのずれを調べておき、電力 偏差テーブル 115によって可変利得増幅器 103に入力される TPC設定値 (つまり、 可変利得制御設置値)を修正する。これにより、ピーク増幅器 106のバイアスを制御 しても電力増幅装置の出力電力を意図した電力にすることができる。  That is, by controlling the bias of the peak amplifier 106 according to the value of the TPC set value set by the transmission power setting unit 110, the gain of the entire power amplifying device changes, so that the TPC set value is set. There is a possibility that a deviation occurs between the power based on the power based on the RF signal input to the modulation unit 101. Accordingly, the deviation is investigated in advance, and the TPC setting value (that is, the variable gain control installation value) input to the variable gain amplifier 103 is corrected by the power deviation table 115. Thereby, even if the bias of the peak amplifier 106 is controlled, the output power of the power amplifying device can be set to the intended power.
[0044] すなわち、ピーク増幅器 106のバイアスを変えることにより、そのピーク増幅器 106 の利得が変化するため、その利得の変化分を補償する必要がある。そこで、送信電 力設定部 110の TPC設定値に応じて可変利得増幅器 103の利得制御の設定値を 変化させる電力偏差テーブル 115を設ける。これによつて、電力偏差テーブル 115 が可変利得増幅器 103の設定値を最適な値に調整することができる。なお、電力偏 差テーブル 115を送信電力設定部 110にカ卩味した上でバイアス値テーブル 112を 作った場合は、別に電力偏差テーブル 115を持たなくてもよい。その場合の構成は 図 5の構成と同じになる。  That is, since the gain of the peak amplifier 106 changes by changing the bias of the peak amplifier 106, it is necessary to compensate for the change in the gain. Therefore, a power deviation table 115 is provided for changing the gain control setting value of the variable gain amplifier 103 in accordance with the TPC setting value of the transmission power setting unit 110. As a result, the power deviation table 115 can adjust the set value of the variable gain amplifier 103 to an optimum value. In addition, when the bias value table 112 is created after considering the power deviation table 115 in the transmission power setting unit 110, the power deviation table 115 may not be provided separately. The configuration in that case is the same as the configuration in FIG.
[0045] 〈実施の形態 4〉  <Embodiment 4>
図 13は、本発明の実施の形態 4に適用される電力増幅装置の構成図である。図 1 3に示す実施の形態 4の電力増幅装置が図 5に示す実施の形態 1の電力増幅装置と 異なる点は、変調方式切替信号 116をバイアス値テーブル 112へ入力する構成が追 カロされた点である。つまり、変調方式が変わると送信電力のピークファクタが変わって 歪特性が変化するので、変調方式切替信号 (変調方式切替情報検出手段） 116によ りバイアス値を変えて歪特性の変化分を補償している。 FIG. 13 is a configuration diagram of a power amplifying device applied to Embodiment 4 of the present invention. The difference between the power amplifying device in the fourth embodiment shown in FIG. 13 and the power amplifying device in the first embodiment shown in FIG. 5 is that the configuration for inputting the modulation method switching signal 116 to the bias value table 112 has been added. Is a point. In other words, if the modulation method changes, the peak factor of the transmission power changes and the distortion characteristics change. Therefore, the modulation method switching signal (modulation method switching information detecting means) 116 The bias value is changed to compensate for the change in distortion characteristics.
[0046] 言 、換えると、実施の形態 4の電力増幅装置は、図示しな 、ベースバンド部力 入 力された変調方式切替信号 116をバイアス値テーブル 112へ入力し、送信電力設定 部 110による TPC設定値と変調方式切替信号 116とに基づいて、ピーク増幅器 106 のバイアス値を切り替えることによって変調方式によって変化するピークファクタに起 因する歪特性を補償して!/ヽる。  In other words, the power amplifying apparatus of the fourth embodiment inputs the modulation scheme switching signal 116 inputted with the baseband unit power to the bias value table 112 and transmits it by the transmission power setting unit 110 (not shown). Based on the TPC setting value and the modulation system switching signal 116, the bias characteristic of the peak amplifier 106 is switched to compensate for distortion characteristics caused by the peak factor that varies depending on the modulation system.
[0047] このようにして、変調方式が変わった場合でも、そのときのピークファクタに応じてバ ィァス値の選び方を切り替えることにより、ピークファクタが変わった場合でも歪特性 の劣化を防ぐことができる。これによつて、ピークファクタが大きくなつた場合でも、ドノ、 ティ増幅器の高効率特性を維持したまま、低歪な最大線形出力電力を保持すること ができる。  [0047] In this way, even when the modulation method changes, by switching the selection of the bias value according to the peak factor at that time, it is possible to prevent the distortion characteristics from deteriorating even when the peak factor changes. . As a result, even when the peak factor increases, the maximum linear output power with low distortion can be maintained while maintaining the high efficiency characteristics of the Donotty amplifier.
産業上の利用可能性  Industrial applicability
[0048] 本発明の電力増幅器は、高効率かつ低歪で無線信号を送信することができる携帯 端末などの移動通信端末に有効に利用することができる。 [0048] The power amplifier of the present invention can be effectively used for a mobile communication terminal such as a mobile terminal capable of transmitting a radio signal with high efficiency and low distortion.

Claims

請求の範囲 The scope of the claims
[1] 入力信号を分岐し、キャリア増幅器とピーク増幅器とによるドハティ増幅機能によつ て電力増幅を行う電力増幅装置であって、  [1] A power amplifying device for branching an input signal and performing power amplification by a Doherty amplification function by a carrier amplifier and a peak amplifier,
ベースバンド信号力 抽出された制御信号を用いて前記ピーク増幅器のバイアス 電圧またはバイアス電流を制御するバイアス電圧制御手段を備える電力増幅装置。  Baseband signal power A power amplifying apparatus comprising bias voltage control means for controlling a bias voltage or a bias current of the peak amplifier using an extracted control signal.
[2] 前記制御信号は、所望の歪特性を満たしながら増幅効率が最大となるように前記ピ ーク増幅器のバイアス電圧を制御する送信電力制御設定値である請求項 1に記載の 電力増幅装置。  [2] The power amplification device according to [1], wherein the control signal is a transmission power control setting value for controlling a bias voltage of the peak amplifier so that amplification efficiency is maximized while satisfying a desired distortion characteristic. .
[3] 前記送信電力制御設定値は、前記ピーク増幅器のバイアス電圧と対応させたバイ ァス値テーブルとしてあら力じめ用意されている請求項 2に記載の電力増幅装置。  3. The power amplifying apparatus according to claim 2, wherein the transmission power control set value is prepared in advance as a bias value table corresponding to the bias voltage of the peak amplifier.
[4] 前記送信電力制御設定値は、前記ピーク増幅器のバイアス電圧の最大値が前記 キャリア増幅器のバイアス電圧以下となる値である請求項 2に記載の電力増幅装置。  4. The power amplifying apparatus according to claim 2, wherein the transmission power control set value is a value at which a maximum value of the bias voltage of the peak amplifier is equal to or less than a bias voltage of the carrier amplifier.
[5] 自己が検出した温度情報を前記バイアス値テーブルに送信し、前記ピーク増幅器 のバイアス電圧と対応する前記送信電力制御設定値を前記温度情報に基づいて補 正する温度検出手段をさらに備える請求項 3に記載の電力増幅装置。  [5] The apparatus further comprises temperature detection means for transmitting temperature information detected by itself to the bias value table and correcting the transmission power control setting value corresponding to the bias voltage of the peak amplifier based on the temperature information. Item 4. The power amplifying device according to Item 3.
[6] 送信電力の変調方式切替情報を前記バイアス値テーブルに送信し、前記ピーク増 幅器のバイアス電圧と対応する前記送信電力制御設定値を前記変調方式切替情報 に基づいて補正する変調方式切替情報検出手段をさらに備える請求項 3に記載の 電力増幅装置。 [6] Modulation scheme switching for transmitting transmission power modulation scheme switching information to the bias value table and correcting the transmission power control setting value corresponding to the bias voltage of the peak amplifier based on the modulation scheme switching information The power amplifying apparatus according to claim 3, further comprising information detecting means.
[7] 前記送信電力制御設定値に応じて、前記キャリア増幅器と前記ピーク増幅器の前 段にある可変利得増幅器のバイアス電圧を制御する電力偏差手段をさらに備える請 求項 3に記載の電力増幅装置。  [7] The power amplifying device according to claim 3, further comprising power deviation means for controlling a bias voltage of a variable gain amplifier preceding the carrier amplifier and the peak amplifier in accordance with the transmission power control setting value. .
PCT/JP2006/314899 2006-07-27 2006-07-27 Power amplifying apparatus WO2008012898A1 (en)

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011151787A (en) * 2010-01-20 2011-08-04 Pohang Univ Of Science & Technology Academy-Industry Cooperation Distributed doherty power amplifier
JP2012049858A (en) * 2010-08-27 2012-03-08 Hitachi Kokusai Electric Inc Power amplifier
EP2980990A4 (en) * 2013-03-26 2017-03-08 Nec Corporation Power amplifier
EP3041133A4 (en) * 2013-08-28 2017-04-26 Kabushiki Kaisha Toshiba Power amplification device and control method for power amplification device
CN107294498A (en) * 2016-03-30 2017-10-24 中国科学院苏州纳米技术与纳米仿生研究所 A kind of asymmetric Doherty amplifiers

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000252914A (en) * 1999-02-25 2000-09-14 Fujitsu Ltd Method and device for control of amplifier
JP2001518731A (en) * 1997-09-30 2001-10-16 モトローラ・インコーポレイテッド Apparatus and method for amplifying a signal
JP2001520828A (en) * 1997-04-17 2001-10-30 クゥアルコム・インコーポレイテッド Amplifier circuit with high linearity operation mode and high efficiency operation mode
JP2002124840A (en) * 2000-10-13 2002-04-26 Mitsubishi Electric Corp Doherty amplifier
JP2004096729A (en) * 2002-08-29 2004-03-25 Hoko Koka Daigakko Doherty amplifier

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001520828A (en) * 1997-04-17 2001-10-30 クゥアルコム・インコーポレイテッド Amplifier circuit with high linearity operation mode and high efficiency operation mode
JP2001518731A (en) * 1997-09-30 2001-10-16 モトローラ・インコーポレイテッド Apparatus and method for amplifying a signal
JP2000252914A (en) * 1999-02-25 2000-09-14 Fujitsu Ltd Method and device for control of amplifier
JP2002124840A (en) * 2000-10-13 2002-04-26 Mitsubishi Electric Corp Doherty amplifier
JP2004096729A (en) * 2002-08-29 2004-03-25 Hoko Koka Daigakko Doherty amplifier

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011151787A (en) * 2010-01-20 2011-08-04 Pohang Univ Of Science & Technology Academy-Industry Cooperation Distributed doherty power amplifier
US8305141B2 (en) 2010-01-20 2012-11-06 Postech Academy-Industry Foundation Distributed Doherty power amplifier
JP2012049858A (en) * 2010-08-27 2012-03-08 Hitachi Kokusai Electric Inc Power amplifier
EP2980990A4 (en) * 2013-03-26 2017-03-08 Nec Corporation Power amplifier
US9667198B2 (en) 2013-03-26 2017-05-30 Nec Corporation Power amplifier
EP3041133A4 (en) * 2013-08-28 2017-04-26 Kabushiki Kaisha Toshiba Power amplification device and control method for power amplification device
CN107294498A (en) * 2016-03-30 2017-10-24 中国科学院苏州纳米技术与纳米仿生研究所 A kind of asymmetric Doherty amplifiers
CN107294498B (en) * 2016-03-30 2020-11-06 中国科学院苏州纳米技术与纳米仿生研究所 Asymmetric Doherty amplifier

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