WO2018109871A1 - Phase and amplitude detection circuit, transmission module and array antenna - Google Patents

Abstract

Provided is a phase and amplitude detection circuit comprising: switches 1, 5 that, using transmission lines 2,3, operate to sequentially switch among three states, namely a first state in which the phase of a reference signal is varied by 0° and then output, a second state in which the phase of the reference signal is varied by 90° and then output, and a third state in which passage of the reference signal is blocked; a mixer 7 that mixes the reference signal and a signal to be measured if in the first or second state, and detects the amplitude of the signal to be measured if in the third state; an LPF 8 that extracts the direct current component from a signal output from the mixer 7; an A/D converter 9 that converts the voltage value of the direct current component output from the LPF 8 to a digital signal; and a signal processing circuit 10 that, in the case of the first state and the second state, calculates the phase difference between the reference signal and the signal to be measured on the basis of two digital signals output respectively from the A/D converter 9, and that, in the case of the third state, calculates the amplitude of the signal to be measured on the basis of the digital signal output from the A/D converter 9.

Description

Phase amplitude detection circuit, transmission module, and array antenna

The present invention relates to a phase / amplitude detection circuit, and more particularly to a phase / amplitude detection circuit for detecting the phase and amplitude of a transmission signal, and a transmission module and an array antenna using the same.

An antenna that can have directivity in the direction of radiating radio waves by arranging a plurality of element antennas and controlling the amplitude and phase of a signal that excites each element antenna is called an array antenna.

FIG. 8 shows an example of a conventional transmitting array antenna. As shown in FIG. 8, the conventional transmission array antenna includes a reference signal generation source 101, an in-phase distributor 102, a plurality of transmission modules 103, and a plurality of element antennas 104. In FIG. 8, a transmission module 103a and a transmission module 103b are shown as the plurality of transmission modules 103. The transmission module 103a and the transmission module 103b have the same configuration. Each transmission module 103 includes a phase shifter 105, a variable attenuator 106, and an amplifier 107. In FIG. 8, an element antenna 104a and an element antenna 104b are shown as the plurality of element antennas 104. The element antenna 104a is connected to the transmission module 103a, and the element antenna 104b is connected to the transmission module 103b. The element antenna 104a and the element antenna 104b have the same configuration.

In addition, in FIG. 8, the alphabets “a” and “b” are attached to the end of the reference numerals so as to distinguish between the plurality of components provided. However, since the transmission module 103a and the transmission module 103b have the same configuration, and the element antenna 104a and the element antenna 104b have the same configuration, in the following description, the transmission module 103a and the transmission module 103b are The element antenna 104a and the element antenna 104b are simply referred to as the “element antenna 104” without being distinguished from each other.

Next, the operation of the conventional transmitting array antenna shown in FIG. 8 will be described.
The reference signal generation source 101 outputs a reference signal. The reference signal is input to the in-phase distributor 102. The in-phase distributor 102 distributes the reference signal to each transmission module 103 in the same phase.

In each transmission module 103, the signal input from the in-phase distributor 102 is input to the phase shifter 105. A phase control signal is input to the phase shifter 105 from the outside. The phase shifter 105 changes the phase of the signal by the amount of phase shift corresponding to the phase control signal input from the outside. A signal output from the phase shifter 105 is input to the variable attenuator 106. An amplitude control signal is input to the variable attenuator 106 from the outside. The variable attenuator 106 changes the amplitude of the signal output from the phase shifter 105 by the amount of attenuation corresponding to the amplitude control signal input from the outside. The signal output from the variable attenuator 106 is input to the amplifier 107. The amplifier 107 amplifies the amplitude of the signal output from the variable attenuator 106. The signal output from the amplifier 107 is input to the element antenna 104. The element antenna 104 radiates the signal as a radio wave.

Among the constituent elements 101 to 107 shown in FIG. 8, in particular, the amplifier 107 has a large variation in characteristics among individuals, and the characteristics vary greatly with temperature. Therefore, due to the unstable characteristics of the amplifier 107, the amplitude and phase of the signal supplied to each element antenna 104 are transferred to the phase shifter 105 and the variable attenuator 106 based on the phase control signal and the amplitude control signal. There is a possibility that the desired directivity may not be obtained in each element antenna 104 because the value fluctuates from the set value. Therefore, it is necessary to detect and calibrate the amplitude and phase of the signal supplied to each element antenna 104.

For example, there is a method described in Patent Document 1 as a conventional calibration method.

In Patent Document 1, the output terminals of adjacent transmission modules are connected with a cable, and the amplitude difference and phase difference of the transmission signals of those transmission modules are detected. Then, the amplitude and phase of the transmission signal of one transmission module are calibrated so that the detected amplitude difference and phase difference are eliminated. However, since this configuration requires that the output terminals of the two transmission modules be connected by a cable, there is a problem in that the degree of freedom of arrangement of these transmission modules is reduced.

Generally, the arrangement of the element antennas 104 is determined according to a function to be realized as an array antenna. On the other hand, the installation location of the transmission module 103 depends not only on the arrangement of the element antennas 104 but also on the size and weight of the transmission module 103 itself and the size and weight of other components not shown in FIG. Also depends. For this reason, it is desirable that the transmission module 103 has a degree of freedom as much as possible.

Therefore, it is desirable that the phase of the transmission signal can be detected for each transmission module without connecting a plurality of transmission modules with cables.

In the conventional transmitting array antenna, as shown in FIG. 8, a reference signal is distributed to each transmission module 103 using an in-phase distributor 102. The reference signal distributed to each transmission module 103 is in phase. Therefore, in each transmission module 103, if the phase difference between the transmission signal transmitted by the transmission module and the reference signal is detected, the phase of the transmission signal supplied to each element antenna 104 can be calibrated.

For example, Patent Document 2 discloses a phase detection circuit using this fact. In the phase detection circuit described in Patent Document 2, the phase of the transmission signal is detected by detecting the phase difference between the transmission signal and the reference signal. The phase detection circuit described in Patent Document 2 has phase shift means for changing the phase of the reference signal by 0 ° or 90 °, and the reference signal and the transmission signal shifted by 0 ° or 90 ° are combined into a single mixer. Mix with.

In Patent Document 2, a voltage (I component) output from the mixer when the reference signal is shifted to 0 ° and a voltage output from the mixer when the reference signal is shifted to 90 °. The voltage (Q component) is acquired in time division. Then, the phase difference between the reference signal and the transmission signal is detected based on these two voltages. Further, the phase of the transmission signal is detected for each transmission module based on the detected phase difference. Then, the phase of the transmission signal of each transmission module is calibrated by calculating the difference between the detected phase and the desired phase.

Japanese Unexamined Patent Publication No. 2016-122895 JP-A 64-068107

As described above, in Patent Document 1, two transmission modules are required for detection of the phase and amplitude of a transmission signal, and the phase and amplitude of the transmission signal cannot be detected with only a single transmission module. There was a problem.

In addition, the phase detection circuit disclosed in Patent Document 2 has a problem that it can detect the phase of the transmission signal but cannot detect the amplitude of the transmission signal. In Patent Document 2, when it is attempted to detect the amplitude of the transmission signal, it is necessary to add another circuit for detecting the amplitude. Therefore, there is a problem that the circuit scale increases.

The present invention has been made to solve such a problem, and a phase / amplitude detection circuit capable of detecting the phase and amplitude of a transmission signal with a single circuit, and transmission using the same. An object is to provide a module and an array antenna.

The present invention provides a first state in which a reference signal and a signal under measurement are input, the phase of the reference signal and the signal under measurement is changed by 0 °, and the reference signal and the signal under measurement are output, the reference signal or A second state in which only one phase of the signal under measurement is changed by 90 ° to output the reference signal and the signal under measurement, and only the signal under measurement is blocked by passing the reference signal A signal switching unit that operates by sequentially switching the three states of the third state to be output, and the signal switching unit connected to the signal switching unit, and the state of the signal switching unit is the first state or the second state From the mixer that mixes the reference signal and the signal under measurement and detects the amplitude of the signal under measurement when the state of the signal switching unit is the third state, and a signal output from the mixer A low-pass filter that extracts a DC component, an A / D converter that converts a voltage of the DC component output from the low-pass filter into a digital signal, and the signal switching unit includes the first state and the A phase difference between the reference signal and the signal under measurement is calculated based on the two digital signals output from the A / D converter in the second state, and the signal switching unit is configured to output the third signal. And a signal processing circuit that calculates the amplitude of the signal under measurement based on the digital signal output from the A / D converter in the state of (2).

According to the phase amplitude detection circuit of the present invention, the signal switching unit sequentially switches the first state, the second state, and the third state, and the digital signal in the three states is sent from the A / D converter. Thus, since the signal processing circuit calculates the phase and amplitude of the signal under measurement based on the digital signal, the phase and amplitude of the signal under measurement can be detected by a single circuit. The effect is obtained.

It is a block diagram which shows the structure of the phase amplitude detection circuit which concerns on Embodiment 1 of this invention. It is a block diagram which shows the structure of the modification of the phase amplitude detection circuit which concerns on Embodiment 1 of this invention. It is a block diagram which shows the structure of the modification of the phase amplitude detection circuit which concerns on Embodiment 1 of this invention. It is a block diagram which shows the structure of the phase amplitude detection circuit which concerns on Embodiment 2 of this invention. It is a block diagram which shows the structure of the modification of the phase amplitude detection circuit which concerns on Embodiment 2 of this invention. It is a block diagram which shows the structure of the transmission module and array antenna which concern on Embodiment 3 of this invention. It is a block diagram which shows the structure of the phase amplitude detection circuit which comprises the array antenna which concerns on Embodiment 3 of this invention. It is a block diagram which shows an example of the conventional array antenna for transmission.

Embodiment 1 FIG.
FIG. 1 is a configuration diagram showing the configuration of a phase amplitude detection circuit according to Embodiment 1 of the present invention. The phase amplitude detection circuit is a circuit for receiving a reference signal and a signal under measurement and detecting a phase difference between the reference signal and the signal under measurement and an amplitude of the signal under measurement. As shown in FIG. 1, the phase / amplitude detection circuit includes a switch 1, a transmission line 2, a transmission line 3, a terminator 4, a switch 5, a terminator 6, a mixer 7, an LPF (Low Pass Filter) 8, and an A / D conversion. And a signal processing circuit 10.

Also, for convenience of explanation, reference numerals 11 to 21 are assigned to the terminals as shown in FIG. That is, the reference signal input terminal 11, the signal under test input terminal 12, the signal processing circuit 10 output terminal 13, the switch 1 input terminal 14, and the switch 1 three output terminals 15, 16, respectively. 17, the three input terminals of the switch 5 are 18, 19, 20 and the output terminal of the switch 5 is 21, respectively.

The reference signal is input to the input terminal 11 of the phase amplitude detection circuit. For example, a reference signal generation source is connected to the input terminal 11. Here, for example, a CW (Continuous Wave) signal is used as the reference signal.

The signal under measurement to be measured is input to the input terminal 12 of the phase amplitude detection circuit. Here, as an example of the signal under measurement, for example, a transmission signal transmitted from the transmission module can be cited.

The switch 1 has one input terminal 14 and three output terminals 15, 16, and 17. The input terminal 14 of the switch 1 is connected to the input terminal 11 of the phase amplitude detection circuit, and a reference signal is input from the input terminal 11. As the connection destination of the switch 1, one of the three output terminals 15, 16, and 17 is selected. The switch 1 outputs a reference signal input to the input terminal 14 from any one of the output terminals 15, 16, and 17 according to the state of the connection destination. Note that switching of the connection destination of the switch 1 is sequentially performed in a preset cycle, for example, in the order of the output terminals 15, 16, and 17. Alternatively, the connection destination of the switch 1 may be switched based on an external control signal.

The transmission line 2 is connected between the output terminal 15 of the switch 1 and the input terminal 18 of the switch 5. The transmission line 2 receives a reference signal from the output terminal 15 of the switch 1 and outputs the reference signal to the input terminal 18 of the switch 5.

The transmission line 3 is connected between the output terminal 16 of the switch 1 and the input terminal 19 of the switch 5. The transmission line 3 receives a reference signal from the output terminal 16 of the switch 1 and outputs the reference signal to the input terminal 19 of the switch 5.

Here, the transmission line 2 and the transmission line 3 are configured such that their electrical lengths are 90 ° different from each other. In the example of FIG. 1, the transmission line 2 changes the phase of the reference signal by 0 ° and outputs it, that is, the transmission line 2 outputs the reference signal as it is, and the transmission line 3 changes the phase of the reference signal by 90 °. Output.

The terminator 4 is connected to the output terminal 17 of the switch 1. The terminator 4 terminates the reference signal input to the output terminal 17 of the switch 1 and blocks the output of the reference signal to the switch 5.

The switch 5 has three input terminals 18, 19, 20 and one output terminal 21. An output terminal 21 of the switch 5 is connected to the mixer 7. As the connection destination of the switch 5, one of the three input terminals 18, 19, and 20 is selected. The switch 5 outputs the reference signal input to any one of the input terminals 18 and 19 from the output terminal 21 to the mixer 7 according to the state of the connection destination. Note that switching of the connection destination of the switch 5 is performed in synchronization with switching of the connection destination of the switch 1.

The terminator 6 is connected to the input terminal 20 of the switch 5. When the connection destination of the switch 5 is the input terminal 20, the terminator 6 terminates the signal input to the input terminal 20 and blocks the output of the signal to the mixer 7.

The mixer 7 is connected to the input terminal 12 of the phase amplitude detection circuit, and the signal under measurement is input from the input terminal 12. The mixer 7 is connected to the output terminal 21 of the switch 5. The mixer 7 mixes the reference signal input from the output terminal 21 of the switch 5 and the signal under measurement input from the input terminal 12, and the sum frequency component, the difference frequency component of the reference signal and the signal under measurement, and The mixed wave including the three components of the higher-order mixed wave component is output to the LPF 8. Here, since the reference signal and the signal under measurement have the same frequency, the difference frequency component between the two signals is a DC component, that is, a constant value. The DC component has a voltage value corresponding to the phase difference between the reference signal and the signal under measurement. On the other hand, when the reference signal is terminated by the terminator 4, only the signal under measurement is input to the mixer 7. In that case, the mixer 7 detects the signal under measurement and outputs a mixed wave including a DC component corresponding to the amplitude of the signal under measurement to the LPF 8. The DC component has a voltage value corresponding to the amplitude of the signal under measurement.

The LPF 8 extracts only the DC component from the plurality of components included in the mixed wave output from the mixer 7 and outputs it to the A / D converter 9. The LPF 8 blocks other components included in the mixed wave and does not output them.

The A / D converter 9 quantizes the DC component voltage value output from the LPF 8 and converts it into a digital signal. The digital signal includes voltage value information corresponding to the phase difference between the reference signal and the signal under measurement and voltage value information corresponding to the amplitude of the signal under measurement. The digital signal is input to the signal processing circuit 10.

The signal processing circuit 10 calculates the relative phase of the signal under measurement with respect to the reference signal and the amplitude of the signal under measurement based on the digital signal output from the A / D converter 9.

The output terminal 13 of the phase / amplitude detection circuit outputs the relative phase and amplitude calculated by the signal processing circuit 10 to the outside.

In FIG. 1, the switch 1, the transmission line 2, the transmission line 3, the terminator 4, and the switch 5 constitute a “signal switching unit” that switches the output of the reference signal and the signal under measurement. The signal switching unit has the following three states (1) to (3), and operates by selecting one of these states. The three states of the signal switching unit are switched by switching the connection destination of the switch 1 and the switch 5.
(1) A first state in which the phase of the reference signal and the signal under measurement is changed by 0 ° and the reference signal and the signal under measurement are output.
(2) a second state in which only the phase of either the reference signal or the signal under measurement is changed by 90 ° and the reference signal and the signal under measurement are output;
(3) A third state in which the passage of the reference signal is blocked and only the signal under measurement is output.

In the present embodiment, the signal processing circuit 10 uses the two digital signals output from the A / D converter 9 when the signal switching unit is in the first state and the second state, The phase difference of the signal under measurement is calculated, and the amplitude of the signal under measurement is calculated using one digital signal output from the A / D converter 9 when the signal switching unit is in the third state. The operation of the signal processing circuit 10 will be described later.

Here, the hardware configuration of the phase amplitude detection circuit according to the first embodiment will be described. In the phase / amplitude detection circuit, the input units are the input terminals 11 and 12, and the output unit is the output terminal 13. The switches 1 and 5 are composed of switching elements such as FETs or PIN diodes. The transmission lines 2 and 3 are composed of, for example, a coaxial line, a strip line, a microstrip line, a coplanar line, and the like. The mixer 7 is composed of a non-linear element such as an FET or a Schottky diode. The LPF 8 is configured by combining a resistor, a capacitor, an inductor, and the like. Each function of the A / D converter 9 and the signal processing circuit 10 is realized by a processing circuit. That is, the phase amplitude detection circuit includes a processing circuit for performing A / D conversion of signals and performing various calculations. Even if the processing circuit is dedicated hardware, a CPU that executes a program stored in a memory (Central Processing Unit, central processing unit, processing unit, arithmetic unit, microprocessor, microcomputer, processor, DSP) It may be.

When the processing circuit is dedicated hardware, the processing circuit is, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC, an FPGA, or a combination thereof. The functions of each part of the A / D converter 9 and the signal processing circuit 10 may be realized by a processing circuit, or the functions of each part may be collectively realized by a processing circuit.

When the processing circuit is a CPU, each function of the A / D converter 9 and the signal processing circuit 10 is realized by software, firmware, or a combination of software and firmware. Software and firmware are described as programs and stored in a memory. The processing circuit reads out and executes the program stored in the memory, thereby realizing the function of each unit. That is, a step for performing A / D conversion of a signal and a step for performing various signal processing include a memory for storing a program to be executed as a result. These programs can also be said to cause a computer to execute the procedures and methods of the A / D converter 9 and the signal processing circuit 10. Here, the memory corresponds to, for example, a nonvolatile or volatile semiconductor memory such as RAM, ROM, flash memory, EPROM, or EEPROM, a magnetic disk, a flexible disk, an optical disk, a compact disk, a mini disk, a DVD, or the like. To do.

Note that a part of the functions of the A / D converter 9 and the signal processing circuit 10 may be realized by dedicated hardware, and a part may be realized by software or firmware. For example, the function of the A / D converter 9 is realized by a processing circuit as dedicated hardware, and the processing circuit of the signal processing circuit 10 is read by the processing circuit stored in the memory and executed. You may make it implement | achieve a function.

As described above, the processing circuit can realize the above functions by hardware, software, firmware, or a combination thereof.

Next, the operation of the phase amplitude detection circuit shown in FIG. 1 will be described.

First, the operation for calculating the phase of the signal under measurement of the phase amplitude detection circuit will be described. Here, the relative phase θ of the signal under measurement with respect to the reference signal, that is, the phase difference between the reference signal and the signal under measurement is calculated as the phase of the signal under measurement.

A reference signal input from the outside to the input terminal 11 is input to the input terminal 14 of the switch 1 and is output from any one of the output terminals 15, 16, and 17 according to the state of the connection destination of the switch 1. .

When the connection destination of the switch 1 is selected as the output terminal 15, the connection destination of the switch 5 is switched to the input terminal 18. This state is the first state described above. At this time, the reference signal input to the input terminal 14 of the switch 1 is output from the output terminal 15 of the switch 1 and input to the input terminal 18 of the switch 5 through the transmission line 2. The reference signal input to the input terminal 18 of the switch 5 is output from the output terminal 21 of the switch 5 and input to the mixer 7.

In addition, the signal under measurement input to the input terminal 12 is input to the mixer 7. The mixer 7 mixes the reference signal input from the output terminal 21 and the signal under measurement input from the input terminal 12. Thus, the mixer 7 generates a mixed wave including a sum frequency component, a difference frequency component, and a higher-order mixed wave component of the signal under measurement and the reference signal, and the mixed wave is input to the LPF 8. The LPF 8 outputs only the DC component that is the difference frequency component among the plurality of components of these mixed waves, and blocks the passage of other components. The voltage value of the DC component includes information on the phase difference between the signal under measurement and the reference signal.

The DC component output from the LPF 8 is input to the A / D converter 9. The A / D converter 9 quantizes the DC component voltage value and converts it into a digital signal. The digital signal output from the A / D converter 9 is input to the signal processing circuit 10. The signal processing circuit 10 stores the digital signal in a memory (not shown).

On the other hand, when the connection destination of the switch 1 is selected as the output terminal 16, the connection destination of the switch 5 is switched to the input terminal 19. This state is the second state described above. At this time, the reference signal input to the input terminal 14 of the switch 1 is output from the output terminal 16 of the switch 1 and input to the input terminal 19 of the switch 5 via the transmission line 3. At this time, the phase of the reference signal is shifted by 90 ° by the transmission line 3. Thus, the reference signal input to the input terminal 19 is output from the output terminal 21 of the switch 5 and input to the mixer 7.

The subsequent operation is the same as when the connection destination of the switch 1 is selected as the output terminal 15. That is, of the mixed wave generated by mixing the reference signal and the signal under measurement by the mixer 7, the DC component voltage value is quantized by the A / D converter 9 and input to the signal processing circuit 10. Is remembered. The voltage value of the DC component obtained here includes information on the phase difference between the reference signal and the signal under measurement.

At this time, the digital signal stored in the memory when the connection destination of the switch 1 is selected as the output terminal 15 is defined as an I component. The digital signal stored in the memory when the connection destination of the switch 1 is selected as the output terminal 16 is defined as the Q component. The signal processing circuit 10 calculates the relative phase of the signal under measurement with respect to the reference signal based on the I component and the Q component stored in the memory. The calculation method will be described below. When the voltage of the I component is VI, the voltage of the Q component is VQ, and the relative phase of the signal under measurement with respect to the reference signal is θ, θ can be obtained by the following equation (1). Therefore, the signal processing circuit 10 calculates the relative phase θ of the signal under measurement with respect to the reference signal using the following equation (1).

Θ = arctan (VQ / VI) (1)

The signal processing circuit 10 stores the relative phase θ thus obtained in the memory as phase data of the signal under measurement.

Next, the operation for calculating the amplitude of the signal under measurement of the phase amplitude detection circuit will be described. The connection destination of the switch 1 is selected as the output terminal 17. In this case, the connection destination of the switch 5 is switched to the input terminal 20. This state is the third state described above.

Therefore, the reference signal input to the input terminal 11 is output from the output terminal 17 of the switch 1 and input to the terminator 4. The terminator 4 terminates the reference signal. For this reason, the reference signal is not input to the mixer 7.

Only the signal under measurement is input to the mixer 7. The signal under measurement input from the input terminal 12 to the mixer 7 is detected by the mixer 7 and a DC component corresponding to the amplitude of the signal under measurement is output. That is, at this time, the mixer 7 functions as a detector.

The mixer 7 outputs a leakage component of the signal under measurement and a harmonic component of the signal under measurement in addition to the DC component.

The LPF 8 passes only the DC component among the plurality of components output from the mixer 7 and blocks the passage of other components. The DC component voltage includes information on the amplitude of the signal under measurement.

The voltage of the DC component output from the LPF 8 is quantized by the A / D converter 9 and converted into a digital signal. The digital signal is input to the signal processing circuit 10. The signal processing circuit 10 stores the digital signal in the memory as amplitude data of the signal under measurement.

As described above, in the phase / amplitude detection circuit according to the present embodiment, the connection destination of the switch 1 and the connection destination of the switch 5 are sequentially switched, and the three data of the I component, the Q component, and the amplitude are sequentially acquired. By calculating the signal processing circuit 10 using these data, the phase difference between the reference signal and the signal under measurement and the amplitude of the signal under measurement can be detected. As described above, in the first embodiment, the phase difference between the reference signal and the signal under measurement and the amplitude of the signal under measurement are detected by the same circuit simply by switching the connection destination of the switches 1 and 5. be able to.

Hereinafter, modifications of the phase amplitude detection circuit according to the first embodiment will be described with reference to FIGS.

In FIG. 1, although it showed about comprising the circuit which has a phase difference of 90 degrees using the transmission line 2 and the transmission line 3, as shown in FIG. 2, instead of the transmission line 2 and the transmission line 3, Even if the 90 °, 3 dB coupler 22 is used, the same effect can be obtained. 2, the same components as those in FIG. 1 are denoted by the same reference numerals as those in FIG. 1, and description thereof is omitted here.

The 90 °, 3 dB coupler 22 shifts the phase of the reference signal input from the output terminal 15 by 0 °, and outputs it from the terminal written “0 °”. In addition, the 90 °, 3 dB coupler 22 shifts the phase of the reference signal input from the output terminal 16 by 90 °, and outputs it from the terminal written “0 °”. In either case, the signal is output from the terminal where “0 °” is written.

In FIG. 2, a switch 23 is provided instead of the switch 5 of FIG. The switch 23 has two input terminals 25 and 26 and one output terminal 27. The output terminal 27 is connected to the mixer 7. The switch 23 outputs a reference signal input to the input terminal 25 to the output terminal 27. The terminator 6 terminates the signal input to the input terminal 26 and cuts off the output to the output terminal 27 of the switch 23. Further, the terminal written as “90 °” of the 90 °, 3 dB coupler 22 is terminated by the terminator 24.

When the connection destination of the switch 1 is selected as the output terminal 15 or the output terminal 16, the connection destination of the switch 23 is switched to the input terminal 25.

When the connection destination of the switch 1 is selected to the output terminal 15, the reference signal is output from the output terminal 15 and input to the 90 °, 3 dB coupler 22. The 90 °, 3 dB coupler 22 shifts the phase of the reference signal by 0 ° and inputs it to the input terminal 25 of the switch 23. This state is the first state described above.

On the other hand, when the connection destination of the switch 1 is selected as the output terminal 16, the reference signal is output from the output terminal 16 and input to the 90 °, 3 dB coupler 22. The 90 °, 3 dB coupler 22 shifts the phase of the reference signal by 90 ° and inputs it to the input terminal 25 of the switch 23. This state is the second state described above.

In FIG. 2, when the connection destination of the switch 1 is the output terminal 17, the reference signal is terminated by the terminator 4 as in FIG. This state is the third state described above.

The 90 °, 3 dB coupler 22 operates as described above according to the state of the connection destination of the switch 1, and therefore performs the same operation as the combination of the transmission line 2 and the transmission line 3 shown in FIG. As a result, the phase amplitude detection circuit in FIG. 2 performs the same operation as the phase amplitude detection circuit in FIG.

Further, as shown in FIG. 3, a phase shifter 57 may be used instead of the transmission lines 2 and 3 of FIG. In FIG. 3, the same components as those in FIG. 1 are denoted by the same reference numerals as those in FIG. 1, and description thereof is omitted here.

As shown in FIG. 3, the phase shifter 57 is connected between the output terminal 15 of the switch 1 and the input terminal 18 of the switch 5. When the output terminal 15 is selected as the connection destination of the switch 1, the phase shifter 57 shifts the phase of the reference signal input from the output terminal 15 by 0 ° according to the control signal input from the outside. Or the phase of the reference signal is shifted by 90 ° and output.

Since the phase shifter 57 operates as described above in accordance with the state of the connection destination of the switch 1 and the control signal from the outside, the operation equivalent to the combination of the transmission line 2 and the transmission line 3 shown in FIG. Do. As a result, the phase amplitude detection circuit of FIG. 3 performs the same operation as the phase amplitude detection circuit of FIG.

In the case of the configuration shown in FIG. 3, the output terminal 16 of the switch 1 and the input terminal 19 of the switch 5 shown in FIG. Accordingly, since the terminals of the switch 1 and the switch 5 can be reduced by one each, the effect that the switches 1 and 5 are reduced in size can be obtained.

In FIG. 3, when the connection destination of the switch 1 is the output terminal 17, the reference signal is terminated by the terminator 4 as in FIG.

2 and FIG. 3 are the same as those in FIG. 1, and thus the description thereof is omitted here.

As described above, in the phase amplitude detection circuit of the first embodiment, the phase of the reference signal is output by shifting the phase by 0 °, the phase of the reference signal is output by shifting the phase by 90 °, and the reference signal is terminated. By sequentially switching the three operations to be performed by the switches 1 and 5, three data of the I component, the Q component, and the amplitude are acquired. Then, by performing calculations in the signal processing circuit 10 using those data, the relative phase θ of the signal under measurement with respect to the reference signal and the amplitude of the signal under measurement can be detected. Thus, in the first embodiment, the relative phase θ of the signal under measurement with respect to the reference signal and the amplitude of the signal under measurement are detected by the same circuit by simply switching the connection destination of the switches 1 and 5. be able to. As a result, the circuit scale of the phase amplitude detection circuit can be reduced. Therefore, when the phase / amplitude detection circuit according to the first embodiment is mounted on the transmission module and the array antenna, the relative phase and amplitude of the transmission signal, which is the signal under measurement, are detected for each transmission module and transmitted with a simple configuration. It becomes possible to calibrate the phase and amplitude of the signal. In addition, when the phase / amplitude detection circuit according to the first embodiment is applied to an array antenna, there is no need to connect two transmission modules with a cable as described in Patent Document 1, and the phase of a signal can be obtained with one transmission module. Therefore, the degree of freedom in installing the transmission module in the array antenna can be ensured.

Embodiment 2. FIG.
FIG. 4 is a configuration diagram of a phase amplitude detection circuit according to the second embodiment of the present invention. In the first embodiment described above, the reference signal has a phase difference of 90 ° in the first state and the second state. However, in the present embodiment, the first state and the second state The signal under measurement has a phase difference of 90 °.

As shown in FIG. 4, the phase / amplitude detection circuit according to the second embodiment includes a switch 28, a terminator 4, a switch 29, a transmission line 30, a transmission line 31, a switch 32, a mixer 7, an LPF (Low Pass Filter) 8. , An A / D converter 9 and a signal processing circuit 10.

Also, for convenience of explanation, numbers are assigned to each terminal as shown in FIG. That is, the reference signal input terminal 11, the signal under test input terminal 12, the signal processing circuit 10 output terminal 13, the switch 28 input terminal 33, and the switch 28 two output terminals 34 and 35, respectively. The input terminal of the switch 29 is 36, the two output terminals of the switch 29 are 37 and 38, the two input terminals of the switch 32 are 39 and 40, respectively, and the output terminal of the switch 32 is 41.

Hereinafter, the same parts as those of the first embodiment shown in FIG. 1 are denoted by the same reference numerals, and description thereof is omitted here.

The switch 28 has one input terminal 33 and two output terminals 34 and 35. The input terminal 11 is connected to the input terminal 33, and a reference signal is input from the input terminal 11. The switch 28 outputs the reference signal input to the input terminal 33 to one of the output terminals 34 and 35. The output terminal 34 is connected to the mixer 7. The output terminal 35 is connected to the terminator 4.

The switch 29 has one input terminal 36 and two output terminals 37 and 38. The input terminal 12 is connected to the input terminal 36, and a signal under measurement is input from the input terminal 12. The switch 29 outputs the signal under measurement input to the input terminal 36 to one of the output terminals 37 and 38. The output terminal 37 is connected to the transmission line 30. The output terminal 38 is connected to the transmission line 31.

The transmission line 30 is connected between the output terminal 37 of the switch 29 and the input terminal 39 of the switch 32. The transmission line 30 shifts the phase of the signal under measurement input from the output terminal 37 of the switch 29 by 0 ° and outputs it to the input terminal 39 of the switch 32.

The transmission line 31 is connected between the output terminal 38 of the switch 29 and the input terminal 40 of the switch 32. The transmission line 30 and the transmission line 31 are configured so that the electrical length differs by 90 °. The transmission line 31 shifts the phase of the signal under measurement input from the output terminal 38 of the switch 29 by 90 ° and outputs it to the input terminal 40 of the switch 32.

The switch 32 has two input terminals 39 and 40 and one output terminal 41. The switch 32 outputs the signal under measurement input to any one of the input terminals 39 and 40 from the output terminal 41 to the mixer 7.

The other components in FIG. 4 are the same as those in FIG. 1, and thus description thereof is omitted here. The hardware configuration of the phase / amplitude detection circuit in FIG. 4 may be the same as that of the phase / amplitude detection circuit according to the first embodiment, and thus the description thereof is omitted here.

Here, in FIG. 4, the switches 28, 29, 32, the transmission lines 30, 31, and the terminator 4 are in the first state, the second state, and the third state. A signal switching unit that operates by selecting one of the states is configured.

Next, the operation of the phase amplitude detection circuit shown in FIG. 4 will be described.

First, the operation for calculating the phase of the signal under measurement will be described. Here, as the phase of the signal under measurement, the relative phase θ of the signal under measurement with respect to the reference signal, that is, the phase difference between the reference signal and the signal under measurement is obtained.

First, the case of the first state will be described. The connection destination of the switch 28 is selected as the output terminal 34. The reference signal input to the input terminal 11 is input to the input terminal 33 of the switch 28 and output from the output terminal 34 of the switch 28 to the mixer 7.

On the other hand, the connection destination of the switch 29 is selected to the output terminal 37.

Here, when the connection destination of the switch 29 is selected as the output terminal 37, the connection destination of the switch 32 is selected as the input terminal 39.

Therefore, the signal under measurement input to the input terminal 36 is output from the output terminal 37 of the switch 29 and input to the input terminal 39 of the switch 32 via the transmission line 30. Thereafter, the signal under measurement is output from the output terminal 41 of the switch 32 and input to the mixer 7.

The subsequent operations are the same as those in the first embodiment. That is, the reference signal and the signal under measurement are mixed by the mixer 7, and the voltage of the DC component included in the mixed wave output as a result is quantized by the A / D converter 9 and input to the signal processing circuit 10. Stored in memory. The DC component voltage (I component) obtained here includes information on the phase difference between the reference signal and the signal under measurement.

Next, the case of the second state will be described. The connection destination of the switch 28 is selected as the output terminal 34. The reference signal input to the input terminal 11 is input to the input terminal 33 of the switch 28 and output from the output terminal 34 of the switch 28 to the mixer 7.

At this time, if the connection destination of the switch 29 is selected as the output terminal 38, the connection destination of the switch 32 is selected as the input terminal 40. The signal under measurement input to the input terminal 12 is input to the input terminal 36 of the switch 29 and output from the output terminal 38 of the switch 29 to the transmission line 31. The transmission line 31 shifts the phase of the signal under measurement by 90 ° and outputs it to the input terminal 40 of the switch 32. The signal under measurement input to the input terminal 40 of the switch 32 is output from the output terminal 41 of the switch 32 and input to the mixer 7.

The subsequent operation is the same as when the connection destination of the switch 29 is selected as the output terminal 37. That is, the reference signal and the signal under measurement are mixed by the mixer 7, and the voltage of the DC component included in the mixed wave output as a result is quantized by the A / D converter 9 and input to the signal processing circuit 10. Stored in memory. The DC component voltage (Q component) obtained here includes information on the phase difference between the reference signal and the signal under measurement.

Then, in the signal processing circuit 10, θ is obtained by the above-described equation (1), where I is the voltage of I component, VQ is the voltage of Q component, V is the relative phase of the signal under measurement with respect to the reference signal,

Next, the operation for calculating the amplitude of the signal under measurement will be described. The connection destination of the switch 28 is selected as the output terminal 35. At this time, the reference signal input to the input terminal 33 of the switch 28 is input from the output terminal 35 to the terminator 4 and not input to the mixer 7. This state is the third state described above.

The connection destination of the switch 29 may select any of the output terminals 37 and 38. Similarly, the connection destination of the switch 32 may select any of the input terminals 39 and 40. However, when the connection destination of the switch 29 is selected as the output terminal 37, the connection destination of the switch 32 is the input terminal 39, and when the connection destination of the switch 29 is selected as the output terminal 38, the connection destination of the switch 32 is input. Terminal 40 is used.

Thus, only the signal under measurement is input to the mixer 7. The signal under measurement input to the mixer 7 is detected by the mixer 7 and a DC component corresponding to the amplitude of the signal under measurement is output. That is, the mixer 7 operates as a detector.

The mixer 7 outputs a leakage component of the signal under measurement and a harmonic component of the signal under measurement in addition to the DC component.

LPF 8 passes the direct current component and blocks the passage of other components. The DC component voltage output from the LPF 8 is quantized by the A / D converter 9 and converted into a digital signal. The digital signal is input to the signal processing circuit 10. The signal processing circuit 10 stores the digital signal in the memory as amplitude data of the signal under measurement.

As described above, in the present embodiment, the switch 28, the switch 29, and the switch 32 are sequentially switched to acquire three data of the I component, the Q component, and the amplitude, and the signal processing circuit 10 performs the calculation. There is an effect that the relative phase θ of the signal under measurement with respect to the reference signal and the amplitude of the signal under measurement can be detected by the same circuit.

In FIG. 4, a circuit having a phase difference of 90 ° using the transmission line 30 and the transmission line 31 is shown. However, the same effect can be obtained by using a 90 °, 3 dB coupler instead of the transmission lines 30, 31. Is obtained. The configuration and operation of the 90 °, 3 dB coupler are the same as those of the 90 °, 3 dB coupler 22 described with reference to FIG. 2 in the first embodiment, and thus the description thereof is omitted here.

Further, as shown in FIG. 5, a phase shift of 90 ° can be provided using a phase shifter 57 instead of the transmission lines 30 and 31. In this case, since the switch 29 and the switch 32 can be eliminated, there is an effect that the phase / amplitude detection circuit is reduced in size.

In the present embodiment, the connection destinations of the switches 28, 29, and 32 are switched in a predetermined cycle, for example, in the order of the first state, the second state, and the third state. Are performed sequentially. Alternatively, the connection destinations of the switches 28, 29, and 32 may be switched based on an external control signal.

As described above, also in the present embodiment, as in the first embodiment, the relative phase θ of the signal under measurement with respect to the reference signal and the measurement target are simply switched by switching the connection destination of the switches 28, 29, and 32. The signal amplitude can be detected by the same circuit. As a result, the circuit scale of the phase amplitude detection circuit can be reduced. Therefore, when the phase amplitude detection circuit of the second embodiment is applied to the transmission module and the array antenna, it is possible to detect and calibrate the signal phase and amplitude with a simple configuration. Further, when the phase amplitude detection circuit of the second embodiment is applied to a transmission module and an array antenna, it is not necessary to connect two transmission modules with a cable as in Patent Document 1, and one transmission module can Since the phase and amplitude can be detected, a degree of freedom in installing the transmission module can be ensured.

Embodiment 3 FIG.
In the third embodiment of the present invention, a transmission module and an array antenna using the phase / amplitude detection circuit shown in the first or second embodiment will be described. FIG. 6 is a configuration diagram of a transmission module and an array antenna according to the third embodiment of the present invention.

6, the array antenna includes a reference signal generation source 42, an in-phase distributor 43, a plurality of transmission modules 44, a plurality of element antennas 45, and a control circuit 46. In FIG. 6, a transmission module 44 a and a transmission module 44 b are shown as the plurality of transmission modules 44. The transmission module 44a and the transmission module 44b have the same configuration. The number of transmission modules 44 may be an arbitrary number. In FIG. 6, an element antenna 45 a and an element antenna 44 b are shown as the plurality of element antennas 45. The element antenna 45a is connected to the transmission module 44a, and the element antenna 45b is connected to the transmission module 44b. Thus, one element antenna 45 is provided for each transmission module 44. The element antenna 45a and the element antenna 45b have the same configuration.

In addition, in FIG. 6, the alphabets “a” and “b” are added to the end of the reference numerals so as to distinguish between the components provided in plural. However, since the transmission module 44a and the transmission module 44b have the same configuration, and the element antenna 45a and the element antenna 45b have the same configuration, in the following description, the transmission module 44a and the transmission module 44b are The element antenna 45a and the element antenna 44b are simply referred to as the “element antenna 44” without being distinguished from each other. The same applies to each component in the transmission module 44.

As shown in FIG. 6, the transmission module 44 includes a directional coupler 47, a phase shifter 48, a variable attenuator 49, an amplifier 50, a directional coupler 51, and a phase amplitude detection circuit 52. Thus, in the present embodiment, the phase amplitude detection circuit 52 is mounted in the transmission module 44. The phase amplitude detection circuit 52 basically has the same configuration and function as any of the phase amplitude detection circuits shown in FIGS. 1 to 5 described in the first and second embodiments. However, the phase amplitude detection circuit 52 according to the present embodiment further generates and outputs a phase control signal for the phase shifter 48 and an amplitude control signal for the variable attenuator 49. This point is different from the first and second embodiments. The configuration of the phase amplitude detection circuit 52 will be described below with reference to FIG.

A configuration example of the phase amplitude detection circuit 52 is shown in FIG. The configuration of the phase / amplitude detection circuit 52 is almost the same as the configuration of the phase / amplitude detection circuit shown in FIG. 1, but in FIG. 7, a signal processing circuit 56 is provided instead of the signal processing circuit 10 of FIG. ing. The difference between the signal processing circuit 56 and the signal processing circuit 10 is that the signal processing circuit 56 generates and outputs a phase control signal for the phase shifter 48 and an amplitude control signal for the variable attenuator 49.

For convenience of explanation, numbers are assigned to terminals as shown in FIGS. That is, the reference signal input terminal 11, the signal under measurement input terminal 12, the control signal input terminal 53 from the control circuit 46 to the phase amplitude detection circuit 52, and the phase amplitude detection circuit 52 to the phase shifter 48. The output terminal of the control signal to be output is 54, and the output terminal of the control signal output from the phase amplitude detection circuit 52 to the variable attenuator 49 is 55. Here, the input terminal 11 and the input terminal 12 are the same as those shown in FIGS.

Hereinafter, each component of the array antenna and the transmission module according to the third embodiment will be described with reference to FIGS. 6 and 7.

6, the control circuit 46 outputs a control signal for setting the phase and amplitude of the signal supplied to the element antenna 45 for each element antenna 45 to the phase amplitude detection circuit 52 of each transmission module 44.

The reference signal generation source 42 outputs a reference signal. Here, for example, a CW (Continuous Wave) signal is used as the reference signal.

The in-phase distributor 43 distributes the reference signal output from the reference signal generation source 42 to each transmission module 44 in the same phase.

The directional coupler 47 outputs a part of the reference signal output from the in-phase distributor 43 to the input terminal 11 and outputs the rest to the phase shifter 48.

A phase control signal is input to the phase shifter 48 from the output terminal 54 of the phase amplitude detection circuit 52. The phase shifter 48 changes the phase of the reference signal input from the directional coupler 47 according to the phase control signal.

The variable attenuator 49 receives an amplitude control signal from the output terminal 55 of the phase amplitude detection circuit 52. The variable attenuator 49 changes the amplitude of the reference signal output from the phase shifter 48 according to the amplitude control signal.

The amplifier 50 amplifies the amplitude of the reference signal output from the variable attenuator 49. The reference signal output from the amplifier 50 is input to the directional coupler 51.

The directional coupler 51 inputs a part of the reference signal input from the amplifier 50 to the input terminal 12, and the remaining signal is input to the element antenna 45. The “part of the reference signal” input to the input terminal 12 is input to the phase amplitude detection circuit 52 as a signal under measurement.

The element antenna 45 radiates the signal input from the directional coupler 51 as a radio wave.

The phase amplitude detection circuit 52 receives a reference signal from the input terminal 11, receives a signal under measurement from the input terminal 12, and receives a control signal from the input terminal 53.

The phase amplitude detection circuit 52 performs the same operation as that described in the first and second embodiments, and detects the relative phase θ of the signal under measurement with respect to the reference signal and the amplitude of the signal under measurement. Further, in the present embodiment, the phase amplitude detection circuit 52 compares the detected relative phase θ with the set value of the phase set by the control signal input from the control circuit 46, and compares the relative phase θ with the set value. A phase correction value corresponding to the difference between the two is obtained, and a phase shift amount value including the correction value is generated as a phase control signal and output to the phase shifter 48. Similarly, the phase amplitude detection circuit 52 compares the detected amplitude of the signal under measurement with the set value of the amplitude set by the control signal input from the control circuit 46, and compares the detected amplitude with the set value. An amplitude correction value corresponding to the difference is obtained, and an attenuation value with the correction value taken into account is generated as an amplitude control signal and output to the variable attenuator 49. Thus, in the present embodiment, the phase / amplitude detection circuit 52 has a correction unit for generating the phase control signal and the amplitude control signal based on the phase correction value and the amplitude correction value.

Next, the operation of the array antenna shown in FIG. 6 will be described.
The reference signal output from the reference signal generation source 42 is distributed in phase to each transmission module 44 by the in-phase distributor 43. A part of the signal input to each transmission module 44 is output to the input terminal 11 by the directional coupler 47. The remaining signal is input to the phase shifter 48. The phase shifter 48 changes the phase of the signal by the amount of phase shift according to the phase control signal input from the output terminal 54 of the phase amplitude detection circuit 52 to the phase shifter 48. A signal output from the phase shifter 48 is input to the variable attenuator 49. The variable attenuator 49 changes the amplitude of the signal by an attenuation amount according to the amplitude control signal output from the output terminal 55 of the phase amplitude detection circuit 52. A signal output from the variable attenuator 49 is input to the amplifier 50. The amplifier 50 amplifies the amplitude of the signal. A part of the signal output from the amplifier 50 is output to the input terminal 12 by the directional coupler 51, and the remaining signal is radiated as a radio wave from the element antenna 45.

Next, the operation of the phase amplitude detection circuit 52 will be described.
In FIG. 7, a part of the reference signal input to the transmission module 44 by the directional coupler 47 is input to the input terminal 11.

A part of the signal under measurement output from the amplifier 50 is input to the input terminal 12 by the directional coupler 51.

A control signal for setting the phase and amplitude of the signal supplied to the element antenna 45 is input from the control circuit 46 to the input terminal 53.

From the reference signal input to the input terminal 11 and the signal under measurement input to the input terminal 12, a digital signal including information on the relative phase θ of the signal under measurement with respect to the reference signal and the amplitude of the signal under measurement is A / Since the operation until the D converter 9 outputs is as described in the first embodiment and the second embodiment, the description thereof is omitted here.

The three digital signals of I component, Q component, and amplitude output from the A / D converter 9 are input to the signal processing circuit 56 and stored in the memory. The signal processing circuit 56 obtains the relative phase θ of the signal under measurement with respect to the reference signal from the voltage VI of the I component and the voltage VQ of the Q component by the above-described equation (1). Further, the signal processing circuit 56 compares the value of θ obtained by the equation (1) with the set value of the phase input from the input terminal 53, obtains a phase correction value corresponding to the difference, and performs the correction. A new phase shift amount is calculated based on the value, and the phase shift amount is output from the output terminal 54 as a phase control signal. The signal processing circuit 56 calculates the amplitude of the signal under measurement from the digital signal input from the A / D converter 9. Then, the signal processing circuit 56 compares the calculated amplitude value with the set amplitude value input from the input terminal 53 to obtain an amplitude correction value corresponding to the difference, and based on the correction value. The new attenuation amount is calculated, and the attenuation amount is output from the output terminal 55 as an amplitude control signal.

Returning again to the description of FIG. 6, the phase control signal output from the output terminal 54 of the phase amplitude detection circuit 52 is input to the phase shifter 48. In the phase shifter 48, the phase of the reference signal is changed from the current value by the amount of phase shift based on the phase control signal.

The amplitude control signal output from the output terminal 55 of the phase amplitude detection circuit 52 is input to the variable attenuator 49. The variable attenuator 49 changes the amplitude of the reference signal from the current value by the amount of attenuation based on the amplitude control signal.

In this way, the control circuit 46 sets the phase and amplitude of the signal supplied to each element antenna 45 by correcting the characteristic variation among the individual amplifiers 50 and the variation in the phase characteristic and amplitude characteristic due to temperature. It is possible to approach the set values of the phase and the amplitude, respectively.

As described above, the signal processing circuit 56 according to the present embodiment includes the phase control signal and the amplitude control in consideration of the phase and amplitude correction values in addition to the functions of the signal processing circuit 10 described in the first and second embodiments. It has a function of a correction circuit that generates a signal.

The array antenna shown in FIG. 6 uses the same circuit to detect the phase and amplitude of the signal under measurement. Moreover, since it is not necessary to connect the output terminals of adjacent transmission modules with a cable as in Patent Document 1, it is possible to increase the flexibility of arrangement of the transmission modules and calibrate the phase and amplitude of the signal with a simple configuration. is there.

Although the configuration of FIG. 7 based on the configuration of FIG. 1 is shown as a configuration example of the phase amplitude detection circuit 52, the configurations of FIGS. 2 to 5 may be used.

FIG. 6 shows an example in which two transmission modules 44 are provided. However, the present invention is not limited to this, and an arbitrary number of transmission modules 44 may be provided. In that case, the same effect can be obtained.

As described above, the transmission module 44 according to the present embodiment receives the reference signal, the phase control signal, and the amplitude control signal from the outside, changes the phase of the reference signal in accordance with the phase control signal, and changes the amplitude. A phase shifter 48 and a variable attenuator 49 that change the amplitude of the reference signal in accordance with the control signal, an amplifier 50 that amplifies the amplitude of the signal output from the phase amplitude switching unit, and a phase amplitude switching A phase amplitude detection circuit 52 that receives the reference signal input to the unit and the signal under measurement that is the output signal of the amplifier 50 and calculates the phase difference between the reference signal and the signal under measurement and the amplitude of the signal under measurement. I have. Also, the phase amplitude detection circuit 52 compares the calculated phase difference value with the phase setting value input from the outside, and includes information on the amount of phase shift that takes into account the phase correction value corresponding to the difference. An amplitude control signal that outputs a phase control signal, compares the calculated amplitude value with an externally input amplitude setting value, and includes attenuation information that takes into account the amplitude correction value corresponding to the difference between them Has a correction circuit as a correction unit for outputting. Therefore, similarly to the first and second embodiments described above, it is possible to detect the phase and amplitude of the transmission signal with one phase amplitude detection circuit. In addition, as described in Patent Document 1, it is not necessary to connect two transmission modules with a cable, and the phase and amplitude of a transmission signal can be detected with one transmission module. As a result, it is possible to ensure the degree of freedom in installing the transmission module.

In addition, the array antenna according to the present embodiment includes a plurality of transmission modules 44, and an element antenna 45 that radiates a signal output from the amplifier 50 of each transmission module 44 as a radio wave, and is in phase with the transmission module. A reference signal generation source 42 for inputting a reference signal and an in-phase distributor 43 are provided. Therefore, in the array antenna, the phase and amplitude of the transmission signal can be detected for each transmission module, and the phase and amplitude of the transmission signal can be calibrated with a simple configuration. Therefore, there is an effect that the degree of freedom of arrangement of the transmission modules in the array antenna is ensured, and the design work of the array antenna becomes easy.

1 switch, 2 transmission line, 3 transmission line, 4 terminator, 5 switch, 6 terminator, 7 mixer, 8 LPF, 9 A / D converter, 10 signal processing circuit, 11, 12, 14, 18, 19, 20, 25, 26, 33, 36, 39, 40 input terminal, 13, 15, 16, 17, 21, 27, 34, 35, 37, 38, 41 output terminal, 22 90 °, 3 dB coupler, 23 switch, 24 terminator, 28 switch, 29 switch, 30 transmission line, 31 transmission line, 32 switch, 42 reference signal generation source, 43 in-phase distributor, 44 transmission module, 45 element antenna, 46 control circuit, 47 directional coupler, 48 phase shifters, 49 variable attenuators, 50 amplifiers, 51 directional couplers, 52 phase amplitude detection circuits, 56 signal processing times , 57 phase shifter, 101 a reference signal generating source, 102 phase splitter, 103 transmission module, 104 antenna elements, 105 phase shifter, 106 a variable attenuator, 107 amplifier.

Claims (7)

1. A first state in which a reference signal and a signal under measurement are input, a phase of the reference signal and the signal under measurement is changed by 0 °, and the reference signal and the signal under measurement are output, the reference signal or the signal under measurement A second state in which only one of the phases is changed by 90 ° to output the reference signal and the signal under measurement, and a third state in which only the signal under measurement is output by blocking the passage of the reference signal A signal switching unit that operates by sequentially switching the three states of
   The reference signal and the signal under measurement are mixed when the state of the signal switching unit is connected to the signal switching unit and the state of the signal switching unit is the first state or the second state, and the state of the signal switching unit is A mixer for detecting the amplitude of the signal under measurement in the third state;
   A low-pass filter that extracts a DC component from the signal output from the mixer;
   An A / D converter that converts the voltage of the DC component output from the low-pass filter into a digital signal;
   When the signal switching unit is in the first state and the second state, the phase difference between the reference signal and the signal under measurement is calculated based on the two digital signals output from the A / D converter. And a signal processing circuit that calculates an amplitude of the signal under measurement based on the digital signal output from the A / D converter when the signal switching unit is in the third state. Phase amplitude detection circuit.
2. The signal switching unit is
   A phase shifter for changing the phase of the reference signal or the signal under measurement by 0 ° and 90 °;
   A terminator for terminating the reference signal;
   A switch for selecting the phase shifter in the case of the first state and the second state, and for selecting the terminator in the case of the third state,
   The phase amplitude detection circuit according to claim 1.
3. The phase shift part is composed of two transmission lines whose electrical lengths are different from each other by 90 °.
   The phase amplitude detection circuit according to claim 2.
4. The phase shift unit is composed of a 90 °, 3 dB coupler,
   The phase amplitude detection circuit according to claim 2.
5. The phase shift unit is composed of a phase shifter.
   The phase amplitude detection circuit according to claim 2.
6. A reference signal, a phase control signal, and an amplitude control signal are input from the outside, and the phase of the reference signal is changed according to the phase control signal, and the amplitude of the reference signal is changed according to the amplitude control signal. A phase amplitude switching unit;
   An amplifier that amplifies the amplitude of the signal output from the phase amplitude switching unit;
   The reference signal input to the phase amplitude switching unit and the signal under measurement that is an output signal of the amplifier are input, and the phase difference between the reference signal and the signal under measurement and the amplitude of the signal under measurement are calculated. The phase amplitude detection circuit according to any one of claims 1 to 5,
   Comparing the phase difference value calculated by the phase amplitude detection circuit with a phase setting value input from the outside, and generating the phase control signal generated based on a phase correction value corresponding to the difference Based on the amplitude correction value corresponding to the difference between the amplitude value calculated by the phase amplitude detection circuit and the amplitude setting value input from the outside while being output to the phase amplitude switching unit A correction unit that outputs the generated amplitude control signal to the phase amplitude switching unit,
   Transmission module.
7. A plurality of the transmission modules according to claim 6 are arranged,
   An element antenna that radiates a signal output from the amplifier of each of the transmission modules as a radio wave;
   A reference signal generator for inputting a reference signal in phase to each of the transmission modules,
   Array antenna.

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