JP2012004822A - Modulation power supply - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a modulation power supply that can reduce a voltage width during switching control and employ a switching element whose breakdown voltage is lower than a maximum output voltage of the modulation power supply.SOLUTION: A high voltage fast modulation power supply 100 has a switching part 114 that is connected to an output of a DC voltage switching part 112, and perform a switching control of the output voltage of the DC voltage switching part 112 according to an operating current of a broad-band amplifier 120. The switching part 114 provides a voltage shift capability that controls the output voltage of the DC voltage switching part 112 by adding/non-adding a particular DC voltage value (Vdc0). The switching part 114 shifts the output voltage of the DC voltage switching part 112 by adding the particular DC voltage value (Vdc0) when an operating current of the broad-band amplifier 120 is equal to or greater than a threshold, and remains the output voltage same by non-adding the particular DC voltage value (Vdc0) when the operating current of the broad-band amplifier 120 is smaller than the threshold.

Description

  The present invention relates to a modulation power supply of a power amplifier using a power supply modulation method, and more particularly to a high power RF amplifier constituting a transmission power amplification device using an ET (Envelope Tracking) method or an EE & R (Envelope Elimination and Restoration) method. The present invention relates to a high-power modulation power supply that supplies a power supply voltage with high efficiency, can follow high-speed voltage changes, and has a high maximum output voltage.

  As a high-efficiency amplification technique, the ET method or the EE & R method has attracted attention, and in order to realize this, a high-speed modulation power source capable of following the output voltage to the envelope change of the output signal is required. In order to improve the overall efficiency of the amplifying device, the modulation power source is also required to have high efficiency.

  In addition, due to the widening of the modulation signal accompanying an increase in communication speed in wireless communication such as a cellular phone, the envelope change is also accelerated, and the change rate of the output voltage required for the modulation power supply is also increased.

  FIG. 1 is a diagram illustrating a configuration of an RF amplifying apparatus using an ET method that requires a modulation power source.

  As shown in FIG. 1, the ET RF amplification device 10 includes an RF signal input terminal 11, an RF amplification unit 12, an AM signal generation unit 13, a delay unit 14, a modulation power supply 15, and an RF signal output terminal 16.

  In the above configuration, the ET RF amplifier 10 linearly amplifies the amplitude-modulated RF signal input to the RF signal input terminal 11 by the RF amplifier 12 and outputs it from the RF signal output terminal 16. At this time, in order to improve the power efficiency of the ET-system RF amplification device 10, the RF amplification unit 12 is supplied to the RF amplification unit 12 according to the envelope amplitude of the RF signal so that the RF amplification unit 12 always operates near saturation. Change the power supply voltage.

  The AM signal generation unit 13 generates an AM signal that sets a power supply voltage to be supplied to the RF amplification unit 12 based on the envelope amplitude of the RF signal and the characteristics of the RF amplification unit 12.

  The delay time of the delay unit 14 is set so that the delay time of the signal passing through the modulation power supply 15 and the delay time of the signal passing through the RF amplification unit 12 coincide.

  The modulation power supply 15 supplies a power supply voltage that changes according to the envelope amplitude of the RF signal to the RF amplification unit 12 based on the AM signal. The modulation power supply 15 is required to change the output voltage at a higher speed as the frequency bandwidth of the RF signal increases.

  Conventionally, as this type of high-speed modulation power supply, for example, there is a configuration described in Patent Document 1.

  FIG. 2 is a circuit diagram showing a configuration of the high-speed modulation power supply described in Patent Document 1.

  As shown in FIG. 2, the high-speed modulation power supply 20 includes an AM signal input terminal 21, a linear amplification unit 22, a broadband amplification unit 23, a current detection unit 24, a control signal generation unit 25, a high efficiency amplification unit 26, and an RF amplification unit. A power supply voltage output terminal 28 is provided.

  In the above configuration, the AM signal input to the AM signal input terminal 21 is amplified to a signal of an appropriate level in the linear amplifier 22 having a feedback loop from the RF amplifier power supply voltage output terminal 28.

  The broadband amplifier 23 can cover the frequency band of the AM signal, and further amplifies the signal amplified to an appropriate level signal in the linear amplifier 22. The signal amplified by the wideband amplifier 23 is output from the RF amplifier power supply voltage output terminal 28 and supplied to the RF amplifier (not shown) as a power supply voltage.

  The current detector 24 converts the instantaneous current flowing through the wideband amplifier 23 into an operating current value signal.

  The control signal generator 25 generates a switching control signal based on the operating current value signal.

  The high-efficiency amplifier 26 is ON / OFF controlled by the switching control signal so as to output a high voltage when the operating current of the broadband amplifier is larger than the threshold, and a low voltage when the operating current is smaller than the threshold. The inductor suppresses the high frequency component from the pulse signal generated by the ON / OFF control, and outputs only the low frequency component from the RF amplifier power supply voltage output terminal.

  The high-speed modulation power supply 20 amplifies and outputs low-frequency components that occupy most of the input AM signal in terms of power by an efficient high-efficiency amplifier 26. On the other hand, since the linearity between the input and output in the high-speed modulation power supply 20 can be ensured by the broadband amplifier 23, it is possible to change the output voltage at high speed and provide a relatively efficient modulation power supply.

  In this configuration example, the broadband amplifier 23 is configured by a class AB push-pull voltage follower, and the high-efficiency amplifier 26 is configured by a DC / DC converter that is switching-controlled.

  As described above, the high-speed modulation power supply 20 improves the accuracy of the output voltage by performing feedback between input and output to the linear amplification unit 22 and the broadband amplification unit 23. This corresponds to the wide band of the high-speed modulation power supply 20. Further, the high efficiency amplifier 26 is controlled by the output current of the broadband amplifier 23. In this case, the power supply output current is mainly supplied from the high-efficiency amplifier 26, so that the high-speed modulation power supply 20 can be made highly efficient.

Special table 2003-533116 gazette

  However, in such a high-speed modulation power supply, when the required maximum output voltage becomes high, the following problems occur.

  In an RF amplifying apparatus using the ET method, an RF amplifying unit to which a power supply voltage is supplied by a high-speed modulation power supply has a high voltage such as gallium nitride (GaN) in order to improve efficiency. The element which can operate | move is used.

  At this time, the maximum output voltage required for the high-speed modulation power supply also increases, and the power supply voltage supplied to the wideband amplification unit and the high efficiency amplification unit also increases accordingly.

  In the high-efficiency amplifying unit, the internal switching element is turned on / off in a state where this high power supply voltage is supplied, so that the slew rate during the on / off operation increases, and the ringing level generated during the on / off operation Switching noise increases. Alternatively, if the time constant inside the high-efficiency amplifier is adjusted so as not to increase the slew rate, the time required for on / off operation increases, the upper frequency limit of power that can be output by the high-efficiency amplifier decreases, and wideband The output power of the amplification unit increases. For this reason, the efficiency of the high-speed modulation power supply decreases.

  In addition, switching elements such as FETs used in the high-efficiency amplifying unit are also selected to have a high withstand voltage corresponding to the increased power supply voltage, and the time required for the on / off operation due to the increase in parasitic capacitance accompanying this. As a result, the efficiency of the high-speed modulation power supply decreases.

  The object of the present invention is to make the voltage change width at the time of switching control smaller than the maximum output voltage of the high-voltage high-speed modulation power supply, and with respect to the switching element used for the switching control, the maximum output voltage of the modulation power supply. Another object of the present invention is to provide a modulation power supply that can employ a switching element having a low withstand voltage.

  A modulation power supply according to the present invention is a modulation power supply that operates in parallel a linear broadband amplifier serving as a voltage source and a high-efficiency amplifier controlled by a current flowing through the broadband amplifier. A multi-value DC voltage source that outputs a DC voltage, a DC voltage switching unit that discretely switches and outputs a plurality of DC voltages supplied from the multi-value DC voltage source according to an input AM signal, and an input signal linearly The broadband amplifying unit for amplifying, the current detecting unit for detecting the operating current flowing through the broadband amplifying unit, and the operating current of the broadband amplifying unit according to the operating current of the broadband amplifying unit so that the operating current is within a certain range. And a voltage shift unit that shifts the output voltage of the DC voltage switching unit.

  A modulation power supply according to the present invention is a modulation power supply that operates in parallel a linear broadband amplifier serving as a voltage source and a high-efficiency amplifier controlled by a current flowing through the broadband amplifier. A multi-value DC voltage source having a floating structure for outputting a DC voltage; a DC voltage switching unit for discretely switching and outputting a plurality of DC voltages supplied from the multi-value DC voltage source according to an input AM signal; and an input signal A broadband amplifying unit that linearly amplifies the current, a current detecting unit that detects an operating current flowing through the broadband amplifying unit, and an operating current of the broadband amplifying unit within a certain range according to the operating current of the broadband amplifying unit Thus, the voltage shift means for shifting the reference potential of the multi-level DC voltage source is employed.

  A modulation power supply according to the present invention is a modulation power supply that operates in parallel a linear broadband amplifier serving as a voltage source and a high-efficiency amplifier controlled by a current flowing through the broadband amplifier. A multi-value DC voltage source that outputs a DC voltage, a DC voltage switching unit that discretely switches and outputs a plurality of DC voltages supplied from the multi-value DC voltage source according to an input AM signal, and an input signal linearly The broadband amplifying unit for amplifying, the current detecting unit for detecting the operating current flowing through the broadband amplifying unit, and the operating current of the broadband amplifying unit according to the operating current of the broadband amplifying unit so that the operating current is within a certain range. And a voltage shift means for switching the voltage step of the output voltage of the DC voltage switching section.

  According to the present invention, it is possible to reduce the voltage width on / off control of the switching unit constituting the high-efficiency amplifying unit with respect to the maximum output voltage as compared with the maximum output voltage of the large-voltage high-speed modulation power supply. In addition, it is possible to suppress an increase in ringing level or switching noise that occurs during the on / off operation of the switching unit.

  In addition, as a switching element used for switching control, an element having a low withstand voltage can be used as compared with the maximum output voltage of a large-voltage high-speed modulation power supply, and a decrease in the upper limit of the frequency that can be output by the high-efficiency amplifier is suppressed. be able to. As a result, a large-voltage high-speed modulation power source that has a large maximum output voltage and can change the output voltage at high speed can be realized with high efficiency.

The figure which shows the structure of the RF amplification device which uses the ET system which requires the conventional modulation power source Circuit diagram showing the configuration of a conventional high-speed modulation power supply Diagram for explaining the basic principle of the present invention 1 is a circuit diagram showing a configuration of a high-voltage high-speed modulation power supply according to Embodiment 1 of the present invention. Operation explanatory diagram of the large-voltage high-speed modulation power supply according to the first embodiment The circuit diagram which shows the structure of the large voltage high-speed modulation power supply which concerns on Embodiment 2 of this invention The circuit diagram which shows the structure of the large voltage high-speed modulation power supply concerning Embodiment 3 of this invention The circuit diagram which shows the structure of the large voltage high-speed modulation power supply which concerns on Embodiment 4 of this invention Operational explanatory diagram of the large-voltage high-speed modulation power supply according to Embodiment 4 above Circuit diagram showing a configuration of a large-voltage high-speed modulation power supply according to Embodiment 5 of the present invention

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Principle explanation)
FIG. 3 is a diagram for explaining the basic principle of the present invention. FIG. 3 is a waveform showing the output of the DC voltage switching unit (high voltage / low voltage) and the output voltage (RF amplifier power supply voltage).

  Figure 3b. As shown in FIG. 2, the conventional high-speed modulation power supply has a large voltage change width at the time of switching of the switching unit. For this reason, the noise level generated at the time of switching increases.

  The present invention performs switching control (shift control) on the output voltage of the DC voltage switching unit connected in parallel with the broadband amplifier so that the operating current of the broadband amplifier is within a certain range. The output voltage of the DC voltage switching unit is connected to the output of the broadband amplification unit through the LPF unit. When the operating current of the broadband amplifying unit exceeds the threshold, the output voltage of the DC voltage switching unit is switched to a higher voltage, and when the operating current of the wideband amplifying unit is less than the threshold, the output voltage of the DC voltage switching unit is changed. Switch to a lower voltage.

  The DC voltage switching unit has a function of switching and outputting the voltage supplied from the multi-level DC voltage source at high speed, and shifting the output voltage in accordance with the operating current of the broadband amplifying unit.

  Figure 3a. As shown in FIG. The voltage change width at the time of switching can be reduced as compared with the conventional method.

  The main advantages of the present invention over the conventional method are as follows.

  (1) The ringing level and switching noise generated during switching can be reduced.

  (2) The switching slew rate can be lowered.

  (3) A switch element with a low withstand voltage (low parasitic capacitance) can be used.

(Embodiment 1)
FIG. 4 is a circuit diagram showing a configuration of the large-voltage high-speed modulation power supply according to Embodiment 1 of the present invention. The present embodiment can be applied to a high-efficiency and wide-band modulation power supply used for an ET or EE & R power supply unit.

  As shown in FIG. 4, the large voltage high speed modulation power supply 100 includes an AM signal input terminal 101, a high efficiency amplification unit 110, a wideband amplification unit 120, a current detection unit 130, and an RF amplification unit power supply voltage output terminal 102.

  The large-voltage high-speed modulation power supply 100 includes a linear broadband amplifying unit 120 serving as a voltage source and a high-efficiency amplifying unit 110 that is controlled by a current flowing through the broadband amplifying unit 120 connected in parallel to the device output. The basic configuration is adopted.

  The high efficiency amplification unit 110 includes a multi-level DC voltage source 111, a DC voltage switching unit 112, a DC voltage switching control unit 113, a switching unit 114, and an LPF unit 115.

  The multi-value DC voltage source 111 outputs a plurality of DC voltages having different values.

  The DC voltage switching unit 112 discretely switches and outputs a DC voltage according to a device input signal for a plurality of DC voltages input from the multi-level DC voltage source 111. The DC voltage switching unit 112 switches and outputs a plurality of DC voltages from the multi-level DC voltage source 111 at high speed.

  The DC voltage switching control unit 113 has a comparator and reference potentials Vref1 to Vref3, and compares the AM signal input to the AM signal input terminal 101 with the reference potentials Vref1 to Vref3 by the comparator, and the DC voltage switching unit 113 A switching signal for switching each switch 112 is generated.

  The switching unit 114 is connected to the output of the DC voltage switching unit 112 and performs switching control of the output voltage of the DC voltage switching unit 112 in accordance with the instantaneous operation current (hereinafter referred to as “operation current” as appropriate) of the broadband amplification unit 120. The switching unit 114 has a voltage shift function that controls addition / non-addition of a specific DC voltage value (Vdc0) with respect to the output voltage of the DC voltage switching unit 112. The DC voltage source 114a supplies a specific DC voltage value (Vdc0) to be added to the output voltage of the DC voltage switching unit 112 in the switching unit 114.

  The switching unit 114 and the DC voltage source 114a are configured to shift the output voltage of the DC voltage switching unit 112 in accordance with the operating current of the broadband amplifying unit 120 so that the operating current of the broadband amplifying unit 120 falls within a certain range. Configure the means.

  The voltage shift function of the switching unit 114 is as follows.

[When the operating current of the broadband amplifier 120 is smaller than the threshold value]
Switching unit 114 is in a non-addition state in which a constant voltage (Vdc0) is not added to the output voltage of DC voltage switching unit 112. In the non-addition state, the switching unit 114 does not add a constant DC voltage value (Vdc0) to the output of the DC voltage switching unit 112, and is a voltage substantially equal to the output voltage of the DC voltage switching unit 112 at that moment. Is output from the switching unit 114. In this non-addition state, the DC voltage switching unit 112 is controlled so that the output voltage of the switching unit 114 is lower than the voltage output from the large voltage high speed modulation power supply 100.

[When the operating current of the broadband amplifier 120 is equal to or greater than a threshold value]
The switching unit 114 is in an addition state in which a constant voltage (Vdc0) is added to the output voltage of the DC voltage switching unit 112. In the addition state, the switching unit 114 outputs a voltage obtained by adding a certain DC voltage value (Vdc0) to the output of the DC voltage switching unit 112 in the switching unit 114. In this addition state, the DC voltage value (Vdc0) is set so that the output voltage of the switching unit 114 is higher than the voltage output from the large-voltage high-speed modulation power supply 100.

  The LPF unit 115 suppresses the high frequency component from the signal obtained by the switching control (on / off control) by the switching unit 114 and outputs an output voltage with less unnecessary components to the RF amplification unit power supply voltage output terminal 102.

  The broadband amplification unit 120 includes a preamplification unit 121 and a final stage amplification unit 122. The broadband amplifier 120 amplifies the input signal linearly. The final stage amplification unit 122 is supplied with the power supply voltage Vcc from the DC voltage source 131.

  The current detector 130 detects an operating current flowing through the wideband amplifier 120. Specifically, the current detection unit 130 detects the operating current of the final stage amplification unit 122 included in the broadband amplification unit 120 using the detection resistor R and the differential amplifier 130a. The Schmitt trigger circuit 130b outputs a switch control signal when the detected operating current is greater than or equal to a predetermined threshold value. The Schmitt trigger circuit 130b prevents hunting of the switch control signal.

  As described above, the high-voltage high-speed modulation power supply 100 includes a wide-band amplifier 120 that operates as a voltage source, a DC voltage supplied from the multi-level DC voltage source 111 according to the input signal, and the LPF unit 115 connected to the output. In the configuration in which the DC voltage switching unit 112 that switches and outputs the current at a high speed is connected in parallel, the current detection unit 130 that detects the operating current flowing through the broadband amplifying unit 120 and the operating current of the broadband amplifying unit 120 are within a certain range. The switching unit 114 that performs switching control of the output voltage of the DC voltage switching unit 112 connected in parallel with the broadband amplification unit 120 is provided. The output voltage of the DC voltage switching unit 112 is connected to the output of the broadband amplifying unit 120 through the switching unit 114 and the LPF unit 115. The switching unit 114 shifts the output voltage by adding a specific DC voltage value (Vdc0) to the output voltage of the DC voltage switching unit 112 when the operating current of the wideband amplification unit 120 is greater than or equal to the threshold value. When the operating current is smaller than the threshold value, a specific DC voltage value (Vdc0) is not added to the output voltage of the DC voltage switching unit 112.

  The operation of the large voltage high speed modulation power supply 100 configured as described above will be described below.

  The AM signal input to the large voltage high speed modulation power supply 100 is amplified to a voltage supplied to the RF amplifier in the broadband amplifier 120 and output.

  When the power gain required for the wideband amplification unit 120 is large, the wideband amplification unit 120 is preferably configured by the preamplification unit 121 and the final stage amplification unit 122, and each of the preamplification unit 121 and the final stage amplification unit 122 is provided. By forming a feedback loop in the amplification means, the linearity between the input and output of the large voltage high speed modulation power supply 100 is improved. Then, by dividing the feedback loop, the delay time of the feedback loop can be reduced, and the decrease in the frequency bandwidth that can be handled by the wideband amplifier 120 due to the feedback loop can be suppressed.

  The current detection unit 130 detects an instantaneous operation current of the wideband amplification unit 120 and generates a switch control signal. In FIG. 4, the current detection unit 130 is configured to detect the operating current supplied from the DC power supply 131 to the final stage amplification unit 122, but may be configured to detect the instantaneous output current of the final stage amplification unit 122.

  The high-efficiency amplifying unit 110 is disposed in parallel with the wide-band amplifying unit 120 between the input and output of the large-voltage high-speed modulation power supply 100.

  The high-efficiency amplification unit 110 includes a multi-level DC voltage source 111 that outputs a plurality of DC voltages having different values, and a DC voltage switching unit 112, and the output of the multi-level DC voltage source 111 is connected to the DC voltage switching unit 112. Is done. The multi-value DC voltage source 111 may be configured to connect a plurality of DC voltage sources in series.

  The DC voltage switching control unit 113 controls the DC voltage switching unit 112 so that a specific DC voltage corresponding to the AM signal input to the large voltage high speed modulation power supply 100 is output from the DC voltage switching unit 112.

  An FET is suitable as a switch constituting the DC voltage switching unit 112 from the viewpoint of high-speed switching. As a control of the DC voltage switching control unit 113 for the DC voltage switching unit 112, a specific DC voltage may be output exclusively and selectively from a plurality of DC voltages input to the DC voltage switching unit 112. However, as shown in FIG. 4, the configuration in which each switch is controlled by the High / Low for the threshold voltage corresponding to each switch for the DC voltage switching unit 112 using the diode for preventing backflow is faster. It is more desirable from the viewpoint of switching and prevention of instantaneous interruption.

  The switching unit 114 is connected to the output of the DC voltage switching unit 112 and performs switching control of the output voltage of the DC voltage switching unit 112 in accordance with the operating current of the broadband amplification unit 120. The switching unit 114 has a voltage shift function that controls addition / non-addition of a specific DC voltage value (Vdc0) with respect to the output voltage of the DC voltage switching unit 112.

  In the state where the instantaneous operating current of the broadband amplifier 120 is larger than the threshold value, a voltage obtained by adding a constant voltage (Vdc0) to the output of the DC voltage switching unit 112 in the switching unit 114 is output from the switching unit 114. . Further, in a state where the instantaneous operating current of the broadband amplifier 120 is smaller than the threshold value, the switching unit 114 does not add a constant voltage (Vdc0) to the output of the DC voltage switching unit 112, and the DC voltage at that moment. A voltage substantially equal to the output voltage of the switching unit 112 is output from the switching unit 114.

  As a switch constituting the switching unit 114, an FET is suitable from the viewpoint of high-speed switching. Instead of the diode constituting the switching unit 114, a switch that operates exclusively with a switch connected in series with the DC voltage source may be arranged. However, the diode is more preferable from the viewpoint of high-speed switching and prevention of instantaneous interruption.

  The LPF unit 115 is connected to the output of the switching unit 114, and a high-efficiency amplification unit that suppresses the high-frequency noise generated by the switching operation of the switching unit 114 and the high-frequency noise generated by the DC voltage switching operation of the DC voltage switching unit 112. 110 output.

  FIG. 5 is an operation explanatory diagram of the high-voltage high-speed modulation power supply 100.

  As shown in FIG. 5, VOUT (t) is an output voltage waveform of the large-voltage high-speed modulation power supply 100 obtained by linearly amplifying the AM signal input to the large-voltage high-speed modulation power supply 100 in the wideband amplification unit 120.

  VOFF (t) is an input voltage waveform to the LPF unit 115 in a state where a specific DC voltage value (Vdc0) is not added in the switching unit 114. VOFF (t) is a voltage waveform in which the output voltage of the multi-value DC voltage source 111 is discretely switched by the DC voltage switching control unit 113 so as to always have a value smaller than VOUT (t). VON (t) is a voltage waveform obtained by adding Vdc0 to VOFF (t) by the switching unit 114. Vdc0 is set so that VON (t) is always larger than VOUT (t).

  The voltage waveform input to the LPF unit 115 is a voltage waveform that varies between VOFF (t) and VON (t) by the switching unit 114 controlled according to the operating current of the wideband amplification unit 120. A signal whose high-frequency component is suppressed by the LPF unit 115 with respect to the waveform is output as the output of the high-efficiency amplifying unit 110.

  The voltage width that causes switching fluctuation by the switching unit 114 is Vdc0, which can be set to a value smaller than the maximum output voltage required for the high-voltage high-speed modulation power supply 100.

  As described above in detail, according to the present embodiment, the large voltage high speed modulation power supply 100 is connected to the output of the DC voltage switching unit 112 and the DC voltage switching unit 112 according to the operating current of the broadband amplification unit 120. Is provided with a switching unit 114 that performs switching control of the output voltage. The switching unit 114 has a voltage shift function that controls addition / non-addition of a specific DC voltage value (Vdc0) with respect to the output voltage of the DC voltage switching unit 112. The switching unit 114 shifts the output voltage by adding a specific DC voltage value (Vdc0) to the output voltage of the DC voltage switching unit 112 when the operating current of the wideband amplification unit 120 is greater than or equal to the threshold value. When the operating current is smaller than the threshold value, a specific DC voltage value (Vdc0) is not added to the output voltage of the DC voltage switching unit 112.

  The switching unit 114 shifts the output voltage of the DC voltage switching unit 112 in accordance with the operating current of the broadband amplifying unit 120 so that the operating current of the broadband amplifying unit 120 falls within a certain range. The voltage change width at the time of switching can be reduced, and noise generated during switching can be reduced.

  In the high-voltage high-speed modulation power supply 100 configured as described above, the low-frequency components that occupy most of the output power are amplified and output by the high-efficiency high-efficiency amplification unit 110 and input / output in the high-voltage high-speed modulation power supply 100. The linearity between them is ensured by the broadband amplifier 120. In addition, the ringing level and switching noise generated during the switching operation can be reduced as compared with the conventional method. Furthermore, it is possible to reduce the parasitic capacitance by selecting a switching element having a withstand voltage lower than that of the conventional method, and to change the output voltage at high speed.

  As described above, it is possible to realize a high voltage and high speed modulation power supply with a large maximum output voltage and capable of changing the output voltage at high speed with high efficiency.

  Here, the accuracy of the output voltage of the large-voltage high-speed modulation power supply 100 is ensured by the characteristics of the broadband amplifier 120.

  By switching control of the DC voltage switching unit 112 so that the operating current of the broadband amplifier unit 120 falls within a certain range, the power consumption in the broadband amplifier unit 120 is limited, and the efficiency of the modulation power supply is increased. Compared to the conventional example, switching width can be reduced by reducing the voltage change width during switch operation, and switch elements with low withstand voltage (low parasitic capacitance, that is, suitable for high-speed operation) are used. Is possible.

(Embodiment 2)
In the first embodiment, an example has been described in which the output voltage of the DC voltage switching unit is shifted in accordance with the operating current of the wideband amplifying unit so that the operating current of the wideband amplifying unit falls within a certain range.

  The second embodiment is an example in which the multi-level DC voltage source and the DC voltage switching unit have a floating structure, and the reference potential of the multi-level DC voltage source is shifted according to the operating current of the broadband amplifier.

  FIG. 6 is a circuit diagram showing a configuration of a large-voltage high-speed modulation power supply according to Embodiment 2 of the present invention. In the description of the present embodiment, the same components as those in FIG.

  As shown in FIG. 6, the large voltage high speed modulation power supply 200 includes an AM signal input terminal 101, a high efficiency amplification unit 210, a wideband amplification unit 120, a current detection unit 130, and an RF amplification unit power supply voltage output terminal 102.

  The high efficiency amplification unit 210 includes a multi-level DC voltage source 211, a DC voltage switching unit 112, a DC voltage switching control unit 113, a switching unit 214, and an LPF unit 115.

  The multi-value DC voltage source 211 outputs a plurality of DC voltages having different values with respect to the reference potential to the DC voltage switching unit 112.

  The switching unit 214 adds / non-adds a specific DC voltage value (Vdc0) to the negative side of the multi-level DC voltage source 211 having a floating configuration when the operating current of the wideband amplifier 120 becomes equal to or greater than a threshold value. A shift function is provided. The DC voltage source 214a supplies a specific DC voltage value (Vdc0) that shifts the reference potential of the multi-level DC voltage source 211 in the switching unit 214.

  The basic configuration and operation of the large-voltage high-speed modulation power supply 200 according to Embodiment 2 of the present invention are the same as those in Embodiment 1.

  The multi-level DC voltage source 211 has a floating structure in which the negative electrode side is connected to the switching unit 214, and the reference potential becomes the shift voltage (Vdc0) or the GND potential by the switching unit 214.

  The multi-value DC voltage source 211 outputs a plurality of DC voltages having different values with respect to the reference potential to the DC voltage switching unit 112. The reference potential of the multi-level DC voltage source 211 is connected to the switching unit 214 and is subjected to switching control based on the instantaneous operation current of the broadband amplifying unit 120. Note that the multi-level DC voltage source 211 may have a configuration in which a plurality of DC voltage sources are connected in series.

  When the operating current of the broadband amplifier 120 is larger than the threshold, the switching unit 214 outputs a constant voltage (Vdc0). As a result, a constant voltage is added to each output of the multi-level DC voltage source 211, and a DC voltage to which the constant voltage is added is input to the DC voltage switching unit 112.

  When the operating current of the broadband amplifier 120 is smaller than the threshold value, the switching unit 214 outputs almost the GND potential, and no voltage is added to each output of the DC voltage switching unit 131. In contrast, a DC voltage to which a constant voltage is not added is input.

  The switching unit 214 and the DC voltage source 214a are voltages that shift the reference potential of the multi-level DC voltage source 211 so that the operating current of the broadband amplifier 120 falls within a certain range according to the operating current of the broadband amplifier 120. The shift means is configured.

  The operation of the large-voltage high-speed modulation power supply 200 is the same as the operation of the large-voltage high-speed modulation power supply 100 in FIG.

  As shown in FIG. 5, VOUT (t) is an output voltage waveform of the large-voltage high-speed modulation power supply 200 in which the AM signal input to the large-voltage high-speed modulation power supply 200 is linearly amplified by the wideband amplifier 120. .

  VOFF (t) is an input voltage waveform to the LPF unit 115 in a state where a specific DC voltage value (Vdc0) is not added in the switching unit 214. VOFF (t) is a voltage waveform in which the output voltage of the multi-level DC voltage source 211 is discretely switched by the DC voltage switching control unit 113 so as to always have a value smaller than VOUT (t). VON (t) is a voltage waveform obtained by adding Vdc0 to VOFF (t) by the switching unit 214. Vdc0 is set so that VON (t) is always larger than VOUT (t).

  The voltage waveform input to the LPF unit 115 is a voltage waveform that varies between VOFF (t) and VON (t) by the switching unit 214 controlled in accordance with the operating current of the wideband amplification unit 120. A signal whose high frequency component is suppressed by the LPF unit 115 with respect to the waveform is output as the output of the high efficiency amplification 310.

  The voltage width that causes the switching fluctuation by the switching unit 214 is Vdc0, and can be set to a value smaller than the maximum output voltage required for the high-voltage high-speed modulation power supply 200.

  As described above, the multi-level DC voltage source 211 and the DC voltage switching unit 112 have a floating structure. When the operating current of the wideband amplification unit 120 becomes equal to or higher than the threshold value, the switching unit 214 When the operating current of the wideband amplifier becomes smaller than the threshold value, the negative electrode of the multi-level DC voltage source 211 is returned to the GND potential.

  The switching unit 214 shifts the reference potential of the multi-level DC voltage source 211 so that the operating current of the broadband amplifying unit 120 falls within a certain range according to the operating current of the broadband amplifying unit 120, and thus the DC voltage switching unit 112. The voltage change width at the time of switching operation can be reduced.

  In the large-voltage high-speed modulation power supply 200 configured as described above, the low-frequency component that occupies most of the output power is amplified and output by the efficient high-efficiency amplification unit 210, as in the first embodiment, and is largely output. The linearity between the input and output in the voltage high-speed modulation power supply 200 is ensured by the broadband amplifier 120. In addition, the ringing level and switching noise generated during the switching operation can be reduced as compared with the conventional method. Furthermore, it is possible to reduce the parasitic capacitance by selecting a switching element having a withstand voltage lower than that of the conventional method, and to change the output voltage at high speed.

  As described above, it is possible to realize a high voltage and high speed modulation power supply with a large maximum output voltage and capable of changing the output voltage at high speed with high efficiency.

(Embodiment 3)
The third embodiment is an example in which an LPF unit is installed on the output side of the DC voltage switching unit.

  FIG. 7 is a circuit diagram showing a configuration of a large-voltage high-speed modulation power supply according to Embodiment 3 of the present invention. In the description of the present embodiment, the same components as those in FIG.

  As shown in FIG. 7, the large voltage high speed modulation power supply 300 includes an AM signal input terminal 101, a high efficiency amplification unit 310, a wideband amplification unit 120, a current detection unit 130, and an RF amplification unit power supply voltage output terminal 102.

  The high efficiency amplification unit 310 includes a multi-level DC voltage source 111, a DC voltage switching unit 112, a DC voltage switching control unit 113, an LPF unit 311, a switching unit 114, and an LPF unit 115.

  The LPF unit 311 suppresses high frequency components included in switching noise generated by the DC voltage switching operation of the DC voltage switching unit 112.

  In the large-voltage high-speed modulated power supply 300 configured as described above, the LPF unit 311 is installed on the output side of the DC voltage switching unit 112. Since the LPF unit 311 suppresses the high frequency component of the noise in the immediate vicinity of the ringing noise generation source, the radiation noise can be reduced.

  Further, it is possible to prevent an increase in the voltage difference between the potential inside the switching unit 114 and the GND potential due to the influence of ringing noise.

  In the present embodiment, the LPF unit 311 is disposed between the output of the DC voltage switching unit 112 and the switching unit 114. What is necessary is just to take the structure which arrange | positions the LPF part 311 between the DC voltage source 211 and the switching part 214. FIG.

(Embodiment 4)
In the first embodiment, the output voltage of the DC voltage switching unit is shifted in accordance with the operating current of the wideband amplification unit, and in the second embodiment, the reference potential of the multi-value DC voltage source having a floating structure is shifted. This voltage shift function is performed by the switching unit in response to the switch control signal of the current detection unit.

  The fourth embodiment is an example in which the output voltage of the DC voltage switching unit is switched to a voltage one step higher. For this reason, a switching part becomes unnecessary.

  FIG. 8 is a circuit diagram showing a configuration of a large-voltage high-speed modulation power supply according to Embodiment 4 of the present invention. In the description of the present embodiment, the same components as those in FIG.

  As shown in FIG. 8, the large voltage high speed modulation power supply 400 includes an AM signal input terminal 101, a high efficiency amplification unit 410, a wideband amplification unit 120, a current detection unit 130, and an RF amplification unit power supply voltage output terminal 102.

  The high efficiency amplifying unit 410 includes a multi-value DC voltage source 411, a DC voltage switching unit 412, a DC voltage switching control unit 413, a logic circuit 414, and an LPF unit 115.

  The multi-level DC voltage source 411 outputs a plurality of DC voltages having different values.

  The DC voltage switching unit 412 discretely switches and outputs a DC voltage according to a device input signal with respect to a plurality of DC voltages input from the multi-level DC voltage source 411. The DC voltage switching unit 412 switches and outputs a plurality of DC voltages from the multi-level DC voltage source 411 at high speed.

  The DC voltage switching unit 412 discretely switches and outputs the DC voltage set by the input AM signal when the operating current of the broadband amplifying unit 120 is smaller than the threshold, and the operating current of the broadband amplifying unit 120 exceeds the threshold. In this case, the output DC voltage of the DC voltage switching unit 412 set by the input AM signal is switched to a DC voltage one step higher.

  The DC voltage switching control unit 413 has a comparator and reference potentials Vref1 to Vref3, and compares the AM signal input to the AM signal input terminal 101 with the reference potentials Vref1 to Vref3 by the comparator, and the DC voltage switching unit 413 A switching signal for switching each switch 412 is generated.

  The logic circuit 414 takes the logic of each switching signal generated in the DC voltage switching control unit 413 and the switch control signal from the current detection unit 130 and outputs the logic to each switch of the DC voltage switching unit 412. The logic circuit 414 configures the logic so that the DC voltage switching unit 412 outputs a DC voltage that is one step higher than the DC voltage determined from the input AM signal when the operating current of the wideband amplification unit 120 exceeds a threshold value. To do.

  The logic circuit 414 constitutes a voltage shift unit that switches the voltage step of the output voltage of the DC voltage switching unit 412 so that the operating current of the broadband amplifying unit 120 falls within a certain range according to the operating current of the wideband amplifying unit 120. .

  Hereinafter, the operation of the large voltage high speed modulation power supply 400 configured as described above will be described.

  The high efficiency amplifier 410 includes a multi-value DC voltage source 411 that outputs a plurality of DC voltages having different values, and the output of the multi-value DC voltage source 411 is connected to the DC voltage switching unit 412. The DC voltage switching control unit 413 discretely outputs a specific DC voltage determined by the AM signal input to the large voltage high speed modulation power supply 400 and the operating current of the wideband amplification unit 120 from the DC voltage switching unit 412. Thus, the DC voltage switching unit 412 is controlled.

  When the operating current of the broadband amplifying unit 120 is smaller than the threshold value, the DC voltage switching is performed so that the DC voltage output from the DC voltage switching unit 412 is lower than the output voltage of the broadband amplifying unit 120 obtained by linearly amplifying the AM signal. Control of the control unit 413 is performed.

  When the operating current of the broadband amplification unit 120 becomes larger than the threshold value, a DC voltage that is one step higher than the DC voltage that the DC voltage switching unit 412 has output so far is output from the DC voltage switching unit 412. The DC voltage switching control unit 413 is controlled. In FIG. 8, the logic circuit 414 takes the logic of each switching signal generated in the DC voltage switching control unit 413 and the switch control signal from the current detection unit 130 and outputs it to each switch of the DC voltage switching unit 412. The logic circuit 414 configures the logic so that the DC voltage switching unit 412 outputs a DC voltage that is one step higher than the DC voltage determined from the input signal when the operating current of the wideband amplification unit 120 exceeds a threshold value. .

  The DC voltage switching unit 412 switches the output DC voltage of the DC voltage switching unit 412 set by the input AM signal to a DC voltage that is higher by one step when the operating current of the wideband amplification unit 120 becomes equal to or greater than the threshold, and multi-level DC A plurality of DC voltages input from the voltage source 411 are discretely switched and output.

  For this reason, in this embodiment, the switching unit used in Embodiments 1 to 3 can be omitted.

  FIG. 9 is an explanatory diagram of the operation of the large-voltage high-speed modulation power supply 400.

  VOUT (t) is an output voltage waveform of the large-voltage high-speed modulation power supply 400 obtained by linearly amplifying the AM signal input to the large-voltage high-speed modulation power supply in the wideband amplifier 120.

  VL (t) is an output voltage of the DC voltage switching unit 412 in a state where the instantaneous operation current of the wide band amplification unit is smaller than the threshold value, and the DC voltage switching control unit is always smaller than VOUT (t). 413 is a voltage waveform in which one of the output DC voltages of the multi-level DC voltage source 411 is discretely switched and output.

  VH (t) is a voltage waveform in which a DC voltage that is one step higher than that of VL (t) is output discretely by the multi-level DC voltage source 411. The DC voltage switching condition of the DC voltage switching control unit 413 is set so that VH (t) always has a voltage value equal to or higher than VOUT (t).

  The voltage waveform input to the LPF unit 115 is subjected to switching control according to the operating current of the broadband amplifier unit 120, and becomes a voltage waveform that varies between VL (t) and VH (t). The signal in which the high-frequency component is suppressed by the unit 115 is output as the output of the high-efficiency amplifying unit 410.

  The voltage width that fluctuates when switching is controlled according to the operating current of the broadband amplifier 120 is set to a voltage step between the DC voltage outputs of the multi-level DC voltage source 411, and is required for the large voltage high speed modulation power supply 400. It is possible to make the value smaller than the maximum output voltage.

  In the large-voltage high-speed modulation power supply 400 configured as described above, the low-frequency components occupying most of the output power are amplified and output by the efficient high-efficiency amplification unit 410, as in the first to third embodiments. The linearity between the input and output in the large-voltage high-speed modulation power supply 400 is ensured by the broadband amplifier 120. In addition, the ringing level and switching noise generated during the switching operation can be reduced as compared with the conventional method. Furthermore, it is possible to reduce the parasitic capacitance by selecting a switching element having a withstand voltage lower than that of the conventional method, and to change the output voltage at high speed.

  As described above, it is possible to realize a high voltage and high speed modulation power supply with a large maximum output voltage and capable of changing the output voltage at high speed with high efficiency.

  In addition, this embodiment can be realized by adding a logic circuit 414 to the control of the DC voltage switching unit 412 having the normal configuration. Further, by setting the voltage step of the multi-level DC voltage source 411, it is possible to change the voltage change width at the time of switching depending on the output voltage of the modulation power supply.

(Embodiment 5)
FIG. 10 is a circuit diagram showing a configuration of a large-voltage high-speed modulation power supply according to Embodiment 5 of the present invention. In the description of the present embodiment, the same components as those in FIG.

  As shown in FIG. 10, the large voltage high speed modulation power supply 500 includes an AM signal input terminal 101, a high efficiency amplification unit 110, a broadband amplification unit 120, a current detection unit 130, a delay adjustment unit 510, and an RF amplification unit power supply voltage output terminal. 102.

  The delay adjustment unit 510 is used in the high-voltage high-speed modulation power supply 500 so that the difference between the delay time of the signal passing through the broadband amplification unit 120 and the delay time of the signal passing through the high-efficiency amplification unit 110 is reduced. The delay unit 511 gives an appropriate delay time between input and output. In FIG. 10, the delay unit 511 is arranged at the input of the broadband amplification unit 120, but is arranged at an appropriate position for the purpose.

  For example, when the delay of the broadband amplification unit 120 is larger than the delay of the high efficiency amplification unit 110, the delay unit 511 is arranged at the input of the high efficiency amplification unit 110. In addition, in order to absorb the delay variation of the wideband amplification unit 120 and the delay variation of the high efficiency amplification unit 110, the delay unit 511 is arranged with respect to the input of the wideband amplification unit 120 and the input of the high efficiency amplification unit 110. It is good.

  The delay means arranged at the input of each amplification unit can fulfill its role as long as a certain delay time can be secured in the frequency band covered by the amplification unit. The delay means arranged at the input of the high-efficiency amplifying unit 110 has no problem even if the upper limit of the frequency indicating a certain delay time is lower than the delay means arranged at the input of the wide-band amplification unit 120.

  As described above, the high-voltage high-speed modulation power supply 500 includes the delay adjustment unit 510, so that an error between the delay time of the signal passing through the broadband amplification unit 120 and the delay of the signal passing through the high-efficiency amplification unit 110 occurs. Therefore, it is possible to prevent the output power of the wideband amplifier 120 from increasing, the power consumption of the high-voltage high-speed modulation power supply 500 from increasing, and the power efficiency from deteriorating.

  The above description is an illustration of a preferred embodiment of the present invention, and the scope of the present invention is not limited to this.

  For example, in the second embodiment, any DC voltage source having a floating structure using the output voltage of the DC voltage switching unit as a reference potential may be used, and any type, number, or connection method may be used. In the fourth embodiment, the logic of the logic circuit may be arbitrary.

  In each of the above embodiments, the name “large voltage high speed modulation power supply” is used. However, this is for convenience of explanation, and may be a large voltage modulation power supply, a high speed modulation power supply, a high power RF amplifier, or the like.

  Furthermore, each circuit unit constituting the modulation power source, for example, the type and number of switches, the type of the DC voltage switching control unit, and the like are not limited to the above-described embodiment. As a matter of course, various compensation circuits may be added to the modulation power source.

  In the modulation power supply according to the present invention, a wideband amplifier and a high efficiency amplifier are arranged in parallel, and the high efficiency amplifier is switching-controlled by the instantaneous operation current of the wideband amplifier, and the voltage change width by the switching control is set to the maximum output voltage. Therefore, it is useful as a modulation power source for a high-power radio transmission apparatus using the ET system that has a large maximum output voltage and changes the output voltage at high speed.

100, 200, 300, 400, 500 High-voltage high-speed modulation power supply 101 AM signal input terminal 102 RF amplifier power supply voltage output terminal 110, 210, 310, 410 High-efficiency amplifier 111, 411 Multi-level DC voltage source 112, 412 DC Voltage switching unit 113, 413 DC voltage switching control unit 114, 214 Switching unit 114a, 131, 214a DC voltage source 115, 311 LPF unit 120 Broadband amplification unit 121 Pre-amplification unit 122 Final stage amplification unit 130 Current detection unit 414 Logic circuit 510 Delay Adjustment Unit 511 Delay Unit

Claims (13)

A modulation power supply that operates in parallel a linear broadband amplifier serving as a voltage source and a high-efficiency amplifier controlled by a current flowing through the broadband amplifier,
A multi-value DC voltage source that outputs a plurality of DC voltages having different values;
A DC voltage switching unit that discretely switches and outputs a plurality of DC voltages supplied from the multi-level DC voltage source according to an input AM signal;
A wideband amplifier for linearly amplifying the input signal;
A current detection unit for detecting an operating current flowing through the broadband amplification unit;
Voltage shifting means for shifting the output voltage of the DC voltage switching unit so that the operating current of the broadband amplifying unit falls within a certain range according to the operating current of the broadband amplifying unit;
Modulated power supply with A modulation power supply that operates in parallel a linear broadband amplifier serving as a voltage source and a high-efficiency amplifier controlled by a current flowing through the broadband amplifier,
A floating multi-level DC voltage source that outputs a plurality of DC voltages having different values;
A DC voltage switching unit that discretely switches and outputs a plurality of DC voltages supplied from the multi-level DC voltage source according to an input AM signal;
A wideband amplifier for linearly amplifying the input signal;
A current detection unit for detecting an operating current flowing through the broadband amplification unit;
Voltage shifting means for shifting the reference potential of the multi-level DC voltage source so that the operating current of the broadband amplifying unit falls within a certain range according to the operating current of the broadband amplifying unit;
Modulated power supply with A modulation power supply that operates in parallel a linear broadband amplifier serving as a voltage source and a high-efficiency amplifier controlled by a current flowing through the broadband amplifier,
A multi-value DC voltage source that outputs a plurality of DC voltages having different values;
A DC voltage switching unit that discretely switches and outputs a plurality of DC voltages supplied from the multi-level DC voltage source according to an input AM signal;
A wideband amplifier for linearly amplifying the input signal;
A current detection unit for detecting an operating current flowing through the broadband amplification unit;
Voltage shift means for switching the voltage step of the output voltage of the DC voltage switching unit so that the operating current of the broadband amplifying unit falls within a certain range according to the operating current of the broadband amplifying unit;
Modulated power supply with   The modulation power supply according to claim 1, wherein the voltage shift unit performs switching control for adding / non-adding a predetermined DC voltage value to an output voltage of the DC voltage switching unit.   The voltage shift means does not add the DC voltage value to the output voltage of the DC voltage switching unit when the operating current of the broadband amplifier is smaller than a threshold, and the operating current of the broadband amplifier is equal to or greater than the threshold. The modulation power supply according to claim 4, wherein the DC voltage value is added to the output voltage of the DC voltage switching unit.   The modulation power supply according to claim 2, wherein the voltage shift unit performs switching control for adding / non-adding a predetermined DC voltage value to a reference potential of the multi-level DC voltage source.   The modulation power supply according to claim 6, wherein the voltage shift unit connects a reference potential of the multi-level DC voltage source to a GND potential when an operating current of the wideband amplifier is smaller than a threshold value.   The modulation power supply according to claim 7, wherein the voltage shift unit adds the DC voltage value to a reference potential of the multi-level DC voltage source when an operating current of the broadband amplification unit is equal to or greater than a threshold value.   The voltage shift means takes a logic of a switching signal for switching each switch of the DC voltage switching unit generated based on an input signal and a switch control signal from the current detection unit, and each of the DC voltage switching unit The modulation power supply according to claim 3, further comprising a logic circuit that outputs to the switch.   4. The modulation power supply according to claim 1, wherein an output voltage of the DC voltage switching unit is lower than a device output voltage when an operating current of the broadband amplifying unit is smaller than a threshold value. 5.   4. The modulation power supply according to claim 1, wherein an output voltage of the DC voltage switching unit is higher than a device output voltage when an operating current of the broadband amplifying unit is equal to or greater than a threshold value. 5.   The modulation power supply according to claim 1, further comprising an LPF unit that suppresses a high-frequency component from an output signal of the DC voltage switching unit. The modulation power supply according to any one of claims 1 to 3, further comprising a delay adjustment unit that reduces a delay time difference between a signal passing through the high-efficiency amplification unit and a signal passing through the broadband amplification unit.

Images