JPH07212166A - Amplitude and phase control circuit - Google Patents

Abstract

PURPOSE:To obtain quick response speed by providing a solid state circuit where the amplitude or the phase shift amount of an input signal is adjusted by an amplitude control signal or a phase control signal from the outside and other changed amount is outputted to be roughly kept to an original value by the control circuit group which is preliminarily incorporated into a ROW. CONSTITUTION:A microwave signal enters from a terminal 1, passes a semiconductor attenuator 4 and is outputted from an output terminal 5. As for the amplitude control signal and the phase control signal of analog pmount, a terminal 6 is impressed from a terminal 7, A/D conversions 8 and 9 are performed for the terminal 6 and the terminal is led to an arithmetic circuit 10. At this stage, an amplitude control signal is added from the terminal 6 to the A/D converter 8, the signal is converted into digital amount, is led to the arithmetic circuit 10, and digital amount for correcting the fluctuation of corresponded control signal voltage and phase is imparted from a data ROM circuit 12. Therefore, the digital amount is made into analog amount in D/A converters 11a, 11b and 11c, each of a semiconductor variable phase converter and a semiconductor variable attenuator is changed, and voltage of desired amplitude and phase is outputted from a terminal 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention, like the input circuit of a high power klystron of a linear accelerator used in nuclear physics, adjusts the signal strength of a microwave signal without changing the phase, or changes the signal strength. The present invention relates to an amplitude / phase control circuit that is used when it is necessary to adjust the phase without the need.

[0002]

2. Description of the Related Art In a multi-stage high-power klystron, it is necessary to appropriately adjust the amplitude and phase of the input signal of each stage. Conventionally, the amplitude and the phase affect each other, so one of them can be kept constant while the other is kept constant. Adjusting only one required a complicated procedure.

For example, when the input signal level is adjusted by the variable attenuator, the phase shift amount of the attenuator changes accordingly. Therefore, it is necessary to adjust the series variable phase shifter to restore the phase. This causes the amount of attenuation to change again, so the adjustment must be repeated several times, such as adjusting the attenuator again. In addition, the same thing is necessary when adjusting the phase, so a laborious and time-consuming operation is required.

[0004]

SUMMARY OF THE INVENTION The present invention has been made based on the above-mentioned background, and a variable phase shifter having a performance with a minimal amount of amplitude change and a variable phase shifter having a performance with a minimal amount of phase shift. It is an object of the present invention to provide an amplitude / phase control circuit which uses an attenuator and which appropriately adjusts the phase shifter and the attenuator at the same time by a single signal of both of them to speed up the response speed.

[0005]

That is, the present invention is directed to a variable phase shifter (hereinafter referred to as "semiconductor variable phase shifter") and a variable attenuator (hereinafter referred to as "semiconductor variable attenuation") each combining a 3 dB hybrid circuit and a semiconductor diode. Is referred to as "device"), and the semiconductor variable phase shifter and semiconductor variable attenuator are external amplitude control signals or phase shift control signals. Adjust the amplitude or phase shift amount of the input signal by the control circuit group built in the ROM in advance, and adjust the phase shift amount when adjusting the amplitude of the input signal and the amplitude when adjusting the phase shift amount. , An amplitude / phase control circuit composed of a solid-state circuit that outputs the respective values while keeping them at their original values.

[0006]

According to the present invention, the data of the amount of phase shift with respect to the change of the amount of change in the semiconductor variable attenuator and the amount of change in the change with respect to the change of the amount of phase shift of the semiconductor variable phase shifter are stored in advance in the ROM. That is, when the amplitude of the input signal is changed, the semiconductor variable attenuator is adjusted by the amplitude control signal from the outside, and the semiconductor phase shift amount of the semiconductor variable attenuator is changed accordingly. The phase shift amount of the variable phase shifter is changed, and at the same time, the change in the attenuation amount of the semiconductor variable phase shifter caused by this change is corrected by the semiconductor variable attenuator. Further, even when the phase shift amount of the semiconductor variable phase shifter is changed by the arrival of the phase shift control signal from the outside, the semiconductor variable attenuator simultaneously corrects the change in the attenuation amount due to the change. In this way, by automatically adjusting the amplitude and phase of the microwave input signal, it is possible to speed up the response.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an amplitude / phase control circuit according to the present invention will be described.
A specific description will be given based on examples.

FIG. 1 is an explanatory diagram showing an example of the configuration of an amplitude / phase control circuit according to the present invention. In FIG. 1, the microwave signal enters from the terminal 1, passes through the semiconductor variable phase shifters 2 and 3, passes through the semiconductor variable attenuator 4, and outputs at the output terminal 5.
Go out from. On the other hand, analog amplitude control signals and phase shift control signals are applied from terminals 6 and 7 to
It is converted into a digital amount by the digital (A / D) converters 8 and 9 and guided to the arithmetic circuit 10.

The data ROM circuit 12 includes a change in the amount of phase shift with respect to the control voltage of the two semiconductor variable phase shifters 2 and 3, a change in the attenuation amount at that time, and a semiconductor variable attenuator 4.
The change in the amount of attenuation with respect to the control voltage and the change in the amount of phase shift corresponding thereto are stored in advance as data.

An amplitude control signal is applied from the terminal 6 to the A / D converter 8
, The signal is converted into a digital amount, guided to the arithmetic circuit 10, and given from the data ROM circuit 12 a corresponding control signal voltage and a digital amount for correcting the fluctuation of the phase. The (D / A) converters 11a, 11b, 11c are converted into analog quantities, and the semiconductor variable phase shifter and the semiconductor variable attenuator are changed, and the voltage of the desired amplitude and phase is output from the terminal 5.
The adjustment of the phase shift amount is similarly performed by the phase control voltage input from the terminal 7.

Example As the semiconductor variable phase shifter and the semiconductor variable attenuator of the present invention, the circuits shown as examples in FIGS. 2 and 3 were used.
In both circuits, 13a and 13b are microwave input terminals, 14a and 14b are their output terminals, 15a and 15b,
15c and 15d are DC blocking capacitors, 16a and 16b
Is a 3 dB hybrid circuit, 22a and 22b are high frequency choke coils, 23a and 23b are bypass capacitors,
21a and 21b are control signal input terminals.

In the semiconductor variable phase shifter shown in FIG.
The input signal from 3a is a 3 dB hybrid circuit 16a.
Is divided into two, and the phase is changed by the variable capacitance diode (or PIN diode) of 17a and 17b,
The signal is adjusted by the variable capacitors 18a and 18b at the end of the .lamda. / 4 length line, passes through the 3 dB hybrid circuit 16a again, and a signal with a changed phase is output from the output terminal 14a. The phase shift control signal voltage is applied to the diode 1 from the terminal 21a.
7a and 17b, the amount of phase shift in the semiconductor variable phase shifter can be changed up to +/− 90 degrees.

FIG. 3 is a diagram showing an example of a semiconductor variable attenuator used in the present invention. In FIG. 3, the input signal from the terminal 13b is divided into two by the 3 dB hybrid circuit 16b as in the case of FIG. 2, and the PIN diode 19a,
It is reflected by 19b and resistors 20a and 20b, and again 3
A signal with a changed amplitude controlled by the amplitude control signal voltage from the terminal 21b goes out from the output terminal 14b through the dB hybrid circuit 16b. This kind of variable attenuator can adjust 0 to 40 dB.

In the present invention, in order to make the phase shift change +/- 180 degrees, two semiconductor variable phase shifters and one semiconductor variable attenuator are connected in series to construct as shown in FIG. did. The maximum change in the phase of the semiconductor variable attenuator due to the change in the attenuation was 15 degrees, and the maximum change in the attenuation due to the change in the phase shift of the semiconductor variable phase shifter was 3 dB.

In the present invention, the attenuation characteristic of the semiconductor variable attenuator and the phase change due to the change in the attenuation amount, the phase shift characteristic of the two semiconductor variable phase shifters and the change in the attenuation amount due to the change in the phase shift amount are described. Six correction tables are placed in the ROM, and the correction values are matrix-calculated by a control signal from the outside to simultaneously adjust the amplitude and phase of the output signal.

[0016]

As described above, since the amplitude / phase control circuit of the present invention has the above-mentioned configuration, the circuit of FIG.
0 to 36 phase for 2.9 GHz microwave signal
The amplitude change when the amplitude was changed by 0 degree was ± 0.5%, and the phase change when the amplitude was changed by 10 to 100% was suppressed within ± 1 degree. In the present invention, since the entire circuit including the semiconductor variable attenuator and the semiconductor variable phase shifter is composed of electronic circuits, the response speed is 10 mS or less, and a quick response is possible.

[Brief description of drawings]

1 is an explanatory diagram showing a schematic configuration of the present invention. 2 is a diagram showing an example of a circuit of the semiconductor variable phase shifter used in the present invention. 3 is a diagram showing an example of a circuit of a semiconductor variable attenuator used in the present invention.

[Explanation of symbols]

1 microwave main signal input terminal 2, 3 semiconductor variable phase shifter 4 semiconductor variable attenuator 5 microwave main signal output terminal 6 amplitude control signal input terminal 7 phase shift control signal input terminal 8, 9 analog / digital converter 10 operation Circuits 11a, 11b, 11c Digital / analog converter 12 Data ROM circuits 13a, 13b Microwave signal input terminals 14a, 14b Microwave signal output terminals 15a, 15b, 15c, 15d DC blocking capacitors 16a, 16b 3dB hybrid circuits 17a, 17b Variable capacitance diode (or PIN diode) 18a, 18b Variable capacitor 19a, 19b PIN diode 20a, 20b Resistor 21a, 21b Control voltage input terminal 22a, 22b High frequency choke coil 23a, 23b Bypass capacitor

Claims (1)

[Claims] 1. An amplitude / phase control circuit for processing an input signal by connecting in series a variable phase shifter and a variable attenuator, each of which is a combination of a 3 dB hybrid circuit and a semiconductor diode. The variable attenuator adjusts the amplitude or the amount of phase shift of the input signal by an amplitude control signal or a phase shift control signal from the outside, and stores the ROM in advance.
A control circuit group built in the output circuit is configured by a solid-state circuit that outputs the phase shift amount when adjusting the amplitude of the input signal and the amplitude when adjusting the phase shift amount so that the amplitudes are maintained at almost original values. Amplitude / phase control circuit.