JP2017169059A - Antenna device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an antenna device that can send pulse wave or continuous wave at the same opening while maintaining antenna gain.SOLUTION: An antenna device 100 comprises an element antenna 1, a transmission reception module 2, a synthesis distribution circuit 3, and an antenna controller 4. The transmission reception module 2 comprises a transmission amplifier that amplifies amplitude of a transmission radio frequency signal output from the synthesis distribution circuit 3, a reception amplifier that amplifies amplitude of a reception radio frequency signal output from the element antenna 1, a variable attenuator, and a PLD that increases attenuation amount of the variable attenuator more, the more the duty cycle of the transmission radio frequency signal is increased.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an antenna device including a plurality of antennas and a plurality of transmission / reception modules each connected to each of the antennas.

  The antenna device of Patent Document 1 using a phased array antenna formed by arranging a plurality of antenna elements to form an aperture array controls a transmission / reception timing of a transmission / reception module by adding a desired delay to a reference trigger for transmission / reception switching. By controlling the on / off timing of the DC power supplied to the transmission / reception module, the average power consumption of the transmission / reception module is reduced.

Japanese Patent Laid-Open No. 2004-236011

In the antenna device of Patent Document 1, when the number of antenna elements is increased by 1 / m in order to reduce the average power consumption to 1 / m (m is an integer of 1 or more), the antenna gain is equal to the number N of antenna elements. Since it is proportional, the antenna gain becomes 1 / m times, and the power of the transmission RF (Radio Frequency) signal of the transmission / reception module is not lowered. However, since the transmission output is proportional to the product of the transmission output power of the transceiver module and the number of antenna elements, the total transmission output is also 1 / m times, and the equivalent isotropic radiated power of the antenna is reduced to (1 / m) ² times. There is a problem such as. Moreover, since the antenna apparatus of patent document 1 switches an antenna opening to time division, when information is superimposed on a transmission wave and transmitted to a missile like a missile illuminator, communication is interrupted when switching to time division, There is a concern that the transmitted wave may not be transmitted correctly due to a phase change.

  The present invention has been made in view of the above, and an object of the present invention is to obtain an antenna device capable of transmitting a pulse wave or a continuous wave through the same aperture while maintaining the antenna gain.

  In order to solve the above-described problems and achieve the object, an antenna device of the present invention includes a plurality of antennas, a plurality of transmission / reception modules each connected to each of the antennas, and a plurality of transmission / reception modules connected to each other. A synthesis / distribution circuit that synthesizes radio frequency signals and distributes transmission radio frequency signals, and an antenna control device connected to a plurality of transmission / reception modules. Each of the plurality of transmission / reception modules includes a transmission amplifier that amplifies the amplitude of the transmission radio frequency signal output from the combining / distributing circuit, a reception amplifier that amplifies the amplitude of the reception radio frequency signal output from the antenna, and an input to the transmission amplifier. A variable attenuator that attenuates the amplitude of the transmitted radio frequency signal and the amplitude of the received radio frequency signal output from the receiving amplifier, and the amount of attenuation of the variable attenuator increases as the duty cycle of the transmitted radio frequency signal increases. And a control unit for raising.

  According to the present invention, there is an effect that a pulse wave or a continuous wave can be transmitted through the same aperture while maintaining the antenna gain.

Configuration diagram of an antenna device according to an embodiment of the present invention Configuration diagram of the transceiver module shown in FIG. The figure which shows the relationship between the input electric power and drain current of the field effect transistor of the gallium nitride semiconductor which comprises the transmission amplifier shown in FIG. The figure which shows the relationship between the input power and output peak power of the field effect transistor of the gallium nitride semiconductor which comprises the transmission amplifier shown in FIG. The figure for demonstrating the 1st operation | movement of the antenna apparatus which concerns on embodiment of this invention. The figure for demonstrating the 2nd operation | movement of the antenna apparatus which concerns on embodiment of this invention.

  Hereinafter, an antenna device according to an embodiment of the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

Embodiment.
FIG. 1 is a configuration diagram of an antenna device according to an embodiment of the present invention. The antenna device 100 according to the embodiment includes a plurality of element antennas 1 that are a plurality of antennas, a plurality of transmission / reception modules 2 connected to each of the element antennas 1, and a plurality of transmission / reception modules 2 to receive RF signals. And a distribution circuit 3 for distributing the transmission RF signal, an antenna control device 4 connected to the transmission / reception module 2, and a power supply device 5 for supplying power to the transmission / reception module 2. In FIG. 1, the number of the plurality of element antennas is represented by N (N is an integer of 1 or more).

  A transmission operation of the antenna device 100 will be described. The transmission RF signal output from the transmission / reception device 6 provided outside the antenna device 100 is distributed by the combining / distributing circuit 3, and each of the distributed transmission RF signals is input to the plurality of transmission / reception modules 2. The transmission RF signal input to the transmission / reception module 2 is attenuated, phase-shifted and amplified, then input to the element antenna 1 and radiated from the element antenna 1 to the space as a pulse wave or continuous wave.

  The reception operation of the antenna device 100 will be described. A pulse wave or continuous wave propagating in space is received by each of the plurality of element antennas 1 and input to the transmission / reception module 2 as a reception RF signal. The received RF signal input to the transmission / reception module 2 is amplified, attenuated and phased, then synthesized by the synthesis / distribution circuit 3 and input to the transmission / reception device 6.

  Next, the configuration of the transmission / reception module 2 will be described with reference to FIG. FIG. 2 is a block diagram of the transmission / reception module shown in FIG. FIG. 2 shows an internal configuration of one transmission / reception module 2 among the plurality of transmission / reception modules 2 shown in FIG. In FIG. 2, a thick line represents a path through which a reception RF signal or a transmission RF signal is transmitted.

  The transmission / reception module 2 includes a switch 12, a switch 13, a variable attenuator 7, a phase shifter 8, a switch 14, a reception amplifier 10, a power supply IC (Integrated Circuit) 16 as a bias voltage control unit, a transmission amplifier 9, a circulator 11, and a control. A PLD (Programmable Logic Device) 15 is provided.

  The power output from the power supply device 5 is supplied to the transmission amplifier 9, the reception amplifier 10, the switches 12, 13 and 14, the phase shifter 8, the PLD 15 and the power supply IC 16. The transmission amplifier 9 and the reception amplifier 10 are configured to include a transistor (not shown), and the transistor is a source-grounded field effect transistor formed of a gallium nitride semiconductor.

  The switch 12 includes a first terminal connected to the switch 13, a second terminal connected to the combining / distributing circuit 3, and a third terminal connected to the switch 14. The switch 12 is driven by a control signal output from the PLD 15 and operates so that the second terminal is connected to the first terminal or the third terminal, or the second terminal is not connected to the first terminal and the third terminal.

  The switch 13 includes a first terminal connected to the reception amplifier 10, a second terminal connected to the variable attenuator 7, and a third terminal connected to the switch 12. The switch 13 is driven by a control signal output from the PLD 15, and operates so that the second terminal is connected to the first terminal or the third terminal, and the second terminal is not connected to the first terminal and the third terminal.

  The switch 14 includes a first terminal connected to the transmission amplifier 9, a second terminal connected to the phase shifter 8, and a third terminal connected to the switch 12. The switch 14 is driven by a control signal output from the PLD 15, and operates so that the second terminal is connected to the first terminal or the third terminal, and the second terminal is not connected to the first terminal and the third terminal.

  The variable attenuator 7 is composed of a variable resistor made of a resistance element or a semiconductor element, and its resistance value is adjusted by a control signal output from the PLD 15. The variable attenuator 7 attenuates the amplitude of the signal input to the transmission amplifier 9 and attenuates the amplitude of the signal output from the reception amplifier 10. The attenuation amount of the variable attenuator 7 is controlled by the PLD 15. As an example of control of the variable attenuator 7, when the variable attenuator 7 is changed by 1 dB between 0 and 31 dB (5 bits), and when it is desired to set it to 18 dB, a command “16 dB” is issued from the antenna controller 4 to the PLD 15 The PLD 15 decodes the command and transmits it to the variable attenuator 7 as a 5-bit signal (10010). According to this configuration, although it is necessary to secure a mounting area for PLD 15 in the transmission / reception module 2, the number of signal lines to the outside of the transmission / reception module 2 can be reduced. However, a pair of signal lines is sufficient for command transfer.

  The phase shifter 8 includes a semiconductor element, a switch, or a magnetic element, and the phase shift amount of the phase shifter 8 is controlled by a control signal output from the PLD 15. The phase shifter 8 shifts the phase of the signal attenuated by the variable attenuator 7, that is, the phase of the signal input to the transmission amplifier 9 and the phase of the signal output from the reception amplifier 10.

  The transmission amplifier 9 is controlled by the power supply IC 16 and amplifies the amplitude of the signal output from the phase shifter 8. The reception amplifier 10 is controlled by the power supply IC 16 and amplifies the amplitude of the signal output from the circulator 11. The circulator 11 outputs the signal amplified by the transmission amplifier 9 to the element antenna 1 and outputs the signal output from the element antenna 1 to the reception amplifier 10.

  The power supply IC 16 controls the gate bias voltage of the field effect transistor constituting the transmission amplifier 9 by the control signal output from the PLD 15. That is, the power supply IC 16 controls the gate bias voltage applied to the transmission amplifier 9 according to the duty cycle of the transmission RF signal, thereby amplifying the signal in the transmission amplifier 9 and the reception amplifier 10 or not amplifying the signal. Turn off amplification.

  The PLD 15 controls the variable attenuator 7, the phase shifter 8, the switch 12, the switch 13, the switch 14, and the power supply IC 16 based on the control signal output from the antenna control device 4.

  The transmission / reception module 2 according to the present embodiment is characterized in that the PLD 15 performs control to increase the attenuation amount of the variable attenuator 7 as the duty cycle of the transmission RF signal increases. Hereinafter, the relationship between the duty cycle of the transmission RF signal and the attenuation amount of the variable attenuator 7 will be specifically described.

The power required by the transmission / reception module 2 is dominated by the power consumption of the transmission amplifier 9. Power P _DC of the field effect transistors constituting the transmission amplifier 9 is expressed by the following equation (1). V _DS is a drain-source voltage, and _ID is a drain current.

FIG. 3 is a diagram showing the relationship between the input power and drain current of the gallium nitride semiconductor field effect transistor constituting the transmission amplifier shown in FIG. The horizontal axis represents the input power P _in of the field effect transistor, and the vertical axis represents the drain current I _D flowing through the field effect transistor.

FIG. 4 is a diagram showing the relationship between the input power and the output peak power of the gallium nitride semiconductor field effect transistor constituting the transmission amplifier shown in FIG. The horizontal axis represents the input power P _in of the field effect transistor, and the vertical axis represents the peak output power P _out of the field effect transistor.

Although depending on the setting of the gate bias voltage of the field effect transistor, there is a positive correlation between the input power Pin and the drain current _ID as shown _in FIG. Thus between the input power P _in of the field effect transistor between the power consumption P _DC positive correlation.

Also when the input power P _in is a pulse, the time average of the power consumption P _DC is pulse width / pulse repetition period, i.e. the duty cycle and the positive correlation. Therefore, when transmitting a high continuous wave or duty cycle pulse, since the power consumption P _DC of the time average is increased, it is necessary to increase the supply power of the power supply device 5, a scale of the antenna device 100 is increased. Therefore transceiver module 2 according to this embodiment, when sending a high continuous wave or duty cycle pulses, the time average value to reduce the input power P _in that does not increase the power consumption P _DC.

At low normal radar operation of duty cycle, but high input power P _in the added efficiency is used in a high region, when sending a high continuous wave or duty cycle pulses, the transceiver module 2, a variable attenuator 7 to increase the attenuation to reduce the input power P _in and. By reducing the input power _{P in,} peak output power _{P out,} as shown in FIG. 4 becomes small. The radar operation with a low duty cycle is an operation when a command indicating that the operation is a low duty cycle is transmitted from the antenna control device 4, and the radar operation with a high duty cycle is a high operation from the antenna control device 4. This is an operation when a command indicating that the operation is a duty cycle is transmitted. For example, the operation mode of mode 1 or mode 2 is determined according to the duty cycle, and the PLD 15 of the transmission / reception module 2 operates according to these modes transmitted from the antenna control device 4.

Here, the total supply power P _total required for the power supply device 5 shown in FIG. 1 is expressed by the following equation (2). The equivalent isotropic radiated power of the antenna device 100 is expressed by the following equation (3). In the following formulas (2) and (3), N represents the number of element antennas 1, G represents the antenna gain, PW represents the pulse width, PRI represents the pulse repetition interval, and Duty represents the duty cycle. .

For example, in order to transmit a continuous wave with the power supply device 5 corresponding to a duty cycle of m, the antenna gain becomes 1 / m because the number of element antennas is 1 / m in the prior art of Patent Document 1, and the equivalent isotropic The radiated power is reduced to (1 / m) ² . On the other hand, in antenna apparatus 100 according to the present embodiment, power consumption _{PDC is set} to 1 / m, and thus the antenna gain is maintained, so that the equivalent isotropic radiated power can be suppressed to a decrease of 1 / m.

  Since antenna apparatus 100 according to the present embodiment does not switch the aperture to time division, when transmitting information to a missile by superimposing information on a transmission wave like a missile illuminator, communication by time division switching of the aperture is performed. There is no concern about disconnection or phase displacement.

In FIG. 4, the peak output power P _out by reducing the input power P _in becomes linear amplification to the input power P _in, although variations in output power between the transceiver module 2 is concerned, previously In the test, the variable attenuator 7 in each transmission / reception module 2 is individually adjusted, and the set value of the attenuation amount of each variable attenuator 7 is stored in a ROM (Read Only Memory) built in the PLD 15, and the operation is performed during the operation. By setting the setting value stored in the ROM to the variable attenuator 7 in each transmission / reception module 2, variations in output power can be suppressed.

In normal radar operation with a low duty cycle, in order to obtain high efficiency, the gate bias voltage is brought close to the pinch-off voltage to approach the class B operation. If the input power Pin is reduced _in this gate bias state, the gain may be reduced and the output power _Pout may be too small, and it may be necessary to increase the gain by bringing the gate bias voltage closer to 0V. Therefore, the antenna device 100 according to the present embodiment can change the gate bias voltage by controlling the power supply IC 16 from the PLD 15, and the setting value of the gate bias voltage is stored in the ROM built in the PLD 15, and the antenna device 100. The gate bias voltage of the power supply IC 16 is controlled by a control signal output from the PLD 15 corresponding to the set value set in the ROM during operation.

  The operation of the antenna device 100 will be described below in association with the terminals of the switches 12, 13, and 14.

  FIG. 5 is a diagram for explaining a first operation of the antenna device according to the embodiment of the present invention. In the antenna device 100, as a first operation, the second terminal of the switch 12 is connected to the first terminal, the second terminal of the switch 13 is connected to the third terminal, and the second terminal of the switch 14 is connected to the first terminal. Connected. As a result, the combining / distributing circuit 3 is connected to the variable attenuator 7 and the phase shifter 8 is connected to the transmission amplifier 9.

  The transmission RF signal output from the combining / distributing circuit 3 is attenuated to a desired amplitude by the variable attenuator 7, and the attenuated transmission RF signal is phase-shifted to a desired phase by the phase shifter 8. Is amplified in amplitude by the transmission amplifier 9. The transmission RF signal amplified by the transmission amplifier 9 is transmitted to the element antenna 1 by the circulator 11 and radiated from the element antenna 1 to the space. Note that the order of the variable attenuator 7 and the phase shifter 8 may be switched.

  FIG. 6 is a diagram for explaining a second operation of the antenna device according to the embodiment of the present invention. In the antenna device 100, as a second operation, the second terminal of the switch 12 is connected to the third terminal, the second terminal of the switch 13 is connected to the first terminal, and the second terminal of the switch 14 is connected to the third terminal. Connected. As a result, the receiving amplifier 10 is connected to the variable attenuator 7, and the phase shifter 8 is connected to the combining / distributing circuit 3.

  The reception RF signal output from the element antenna 1 is sent to the reception amplifier 10 by the circulator 11, and the reception RF signal whose amplitude is amplified by the reception amplifier 10 is attenuated to a desired amplitude by the variable attenuator 7, and is attenuated. The RF signal is phase-shifted to a desired phase by the phase shifter 8. The phase-shifted received RF signal is sent to the combining / distributing circuit 3. Note that the order of the variable attenuator 7 and the phase shifter 8 may be switched.

As described above, the antenna device according to the present embodiment includes a plurality of antennas, a plurality of transmission / reception modules each connected to each of the element antennas, and a plurality of transmission / reception modules to receive a reception radio frequency signal. A combining / distributing circuit that combines and distributes a transmission radio frequency signal and an antenna control device connected to a plurality of transmitting / receiving modules are provided. Each of the plurality of transmission / reception modules includes a transmission amplifier that amplifies the amplitude of the transmission radio frequency signal output from the combining / distributing circuit, a reception amplifier that amplifies the amplitude of the reception radio frequency signal output from the antenna, and an input to the transmission amplifier. A variable attenuator that attenuates the amplitude of the transmitted radio frequency signal and the amplitude of the received radio frequency signal output from the receiving amplifier, and the amount of attenuation of the variable attenuator increases as the duty cycle of the transmitted radio frequency signal increases. And a controller for increasing. With this configuration, the input power P _in the higher transmission amplifier attenuation of the variable attenuator is increased is reduced, the output peak power P _out becomes smaller. Therefore, the equivalent isotropic radiated power can be suppressed to a decrease of 1 / m while maintaining the antenna gain.

  The configuration described in the above embodiment shows an example of the contents of the present invention, and can be combined with another known technique, and can be combined with other configurations without departing from the gist of the present invention. It is also possible to omit or change the part.

  1 element antenna, 2 transmission / reception module, 3 combining / distributing circuit, 4 antenna control device, 5 power supply device, 6 transmission / reception device, 7 variable attenuator, 8 phase shifter, 9 transmission amplifier, 10 reception amplifier, 11 circulator, 12, 13 , 14 switch, 16 power IC, 100 antenna device.

Claims (4)

Multiple antennas,
A plurality of transceiver modules each connected to each of the antennas;
A synthesizing / distributing circuit connected to the plurality of transmitting / receiving modules for synthesizing a reception radio frequency signal and distributing a transmission radio frequency signal;
An antenna control device connected to the plurality of transceiver modules;
With
Each of the plurality of transmission / reception modules is
A transmission amplifier that amplifies the amplitude of the transmission radio frequency signal output from the combining and distributing circuit;
A receiving amplifier that amplifies the amplitude of the received radio frequency signal output from the antenna;
A variable attenuator that attenuates the amplitude of the transmission radio frequency signal input to the transmission amplifier and attenuates the amplitude of the reception radio frequency signal output from the reception amplifier;
A controller that increases the attenuation of the variable attenuator as the duty cycle of the transmission radio frequency signal increases;
An antenna device comprising: The control unit stores a set value of the attenuation amount of the variable attenuator,
The antenna apparatus according to claim 1, wherein an attenuation amount of the variable attenuator is controlled by a setting value stored in the control unit.   The antenna apparatus according to claim 1, further comprising a bias voltage control unit configured to control a gate bias voltage applied to the transmission amplifier according to a duty cycle of the transmission radio frequency signal. The control unit stores a set value of the gate bias voltage,
The antenna device according to claim 3, wherein the gate bias voltage of the bias voltage control unit is controlled by a control signal output from the control unit corresponding to the set value.

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