JPH0221701A - Step attenuator - Google Patents

Abstract

PURPOSE:To obtain a step attenuator having an attenuator characteristic with excellent reproducibility and able to be driven electrically by connecting the attenuator to one terminal of a latching circulator and short-circuiting the other end of the attenuator. CONSTITUTION:A signal inputted from a terminal 1a is outputted from a terminal 1b as it is. Moreover, the signal inputted from the terminal 1a passes through an attenuator 2 sequentially in figure (b), reflected at the other end of the attenuator 2 and outputted through the attenuator 2 and the terminal 1c again from the terminal 1b. Since the transmission characteristic between the terminals 1a and 1b is divided into the cases of passing through the attenuator and not through the attenuator depending on the setting of state of the latching circulator 1, a function of the step attenuator is provided. Thus, the connection or nonconnection of the attenuator 2 is selected. Thus, reproducibility is provided to the attenuation, the attenuator with very high accuracy is obtained and the step attenuator without any mechanical moving part and able to be driven electrically is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a step attenuator that attenuates the power level of a high frequency signal in stages.

[Conventional technology]

FIG. 7 is a principle diagram of a conventional waveguide-type step attenuator that is commercially available. In the figure, 3 is a waveguide;
4 is a resistor.

Next, the operation will be explained. FIG. 7(a) shows a state in which the resistor 4 is not inserted into the waveguide 3. In this state, there is no loss due to the resistor, so the loss of this waveguide circuit is determined only by the characteristics of the waveguide.

On the other hand, FIG. 7(b) shows a state in which the resistor 4 is inserted into the waveguide 3. In this state, the loss due to the resistor is added to the loss due only to the waveguide. The loss due to the resistor is determined by the width and insertion length of the resistor inserted into the waveguide.

Therefore, a step attenuator can be constructed by making it possible to mechanically set the above two states (whether or not a resistor is inserted).

[Problem to be solved by the invention]

Since the conventional step attenuator is configured as described above, the amount of attenuation depends on the width and insertion length of the resistor, so it is difficult to reproduce the amount of attenuation due to the limit of mechanical accuracy, especially when used at high frequencies. There were problems such as not being able to obtain sex.

This invention was made in order to solve the problems of the conventional ones as described above, and the purpose is to obtain a step attenuator that has attenuation characteristics with good reproducibility and can be driven electrically. shall be.

[Means to solve the problem]

In the step attenuator according to the present invention, the attenuator is connected to one terminal of a latching circulator, and the other end of the attenuator is short-circuited.

Further, adjacent terminals of the four-terminal switch are connected via an attenuator.

[Effect]

In this invention, since the latching circulator is used to select whether or not to connect the attenuator,
The reproducibility of the step attenuator is determined only by the characteristics of the latching circulator, and the reproducibility can be made very good, and by using the latching circulator, it is possible to obtain one that does not have mechanically moving parts.

In addition, since the 4-terminal switch is used to select whether or not to connect the attenuator, the reproducibility of the step attenuator is determined only by the characteristics of the waveguide switch, making it possible to improve the reproducibility very well. By using an electrically drivable four-terminal switch, it is possible to eliminate mechanically movable parts.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a step attenuator according to an embodiment of the present invention. In the figure, ■ is a latching circulator, la, lb and IC are terminals of the latching circulator l, and 2 is an attenuator.

Next, the operation will be explained. FIG. 1(a) shows the case where the latching circulator is set to the shape Ml.
Figure (b) shows the case where the latching circulator is set to state 2.

In FIG. 1(a), a signal inputted from terminal 1a is outputted from terminal 1b as is. Also, in FIG. 1(b), the signal input from terminal 1a passes through terminal IC and attenuator 2 in sequence, is reflected at the other end of attenuator 2, passes through attenuator 2 and terminal 1c again, and exits from terminal 1b. Output.

Therefore, the transmission characteristics between the terminals 1a and lb can be divided into cases where the signal passes through the attenuator and cases where the signal does not pass through the attenuator depending on the state setting of the latching circulator, so that the transmission characteristic has the function of a step attenuator.

In this way, according to this embodiment, the connection or non-connection of the attenuator is selected by the latching circulator, so that the attenuation amount is reproducible and highly accurate, and the mechanical It is possible to obtain an electrically drivable step attenuator without any moving parts.

Figures 2 and 3 show other embodiments using this latching circulator, and Figure 2 shows an example in which the attenuator is made variable type 2a so that the amount of attenuation of the step attenuator can be set freely. It is.

Furthermore, Fig. 3 shows a configuration in which a plurality of the circuits shown in Fig. 1 or Fig. 2 are connected in series, and a multi-stage step attenuator is constructed by setting the combination of the states of the latching circulators and the attenuation amount of each attenuator. be able to.

In the embodiments shown in FIGS. 1 to 3, only the polarity of the solenoid of the latching circulator is mechanically switched, but the polarity may also be switched electrically.

Furthermore, an answerback signal may be taken out from the latching circulator to confirm the switching operation.

Furthermore, although the above embodiments have been explained in the case of a waveguide circuit, the present invention can be similarly applied to a coaxial circuit or the like.

Further, in the above description, a step attenuator was realized by a combination of a latching circulator and an attenuator, but it can also be realized by a combination of a four-terminal switch and an attenuator.

FIG. 4 shows another embodiment of the present invention realized by a combination of this four-terminal switch and an attenuator, and in the figure,
5 is a waveguide switch (4-terminal switch), 5a, 5b, 5c
Further, 5d is each terminal of the waveguide switching device 5, and 6 is an attenuator.

Next, the operation will be explained. FIG. 4 (al) shows the case where the waveguide switch is set to state DI, and FIG. 4(b) shows the case where the waveguide switch is set to state 2.

In FIG. 4(a), the signal inputted from the terminal 5a is outputted from the terminal 5b as it is. Further, in FIG. 4 (bl), a signal input from the terminal 5a passes through the terminal 5d, the attenuator 6, and the terminal 5C in sequence, and is output from the terminal 5b.

Therefore, the transmission characteristics between the terminals 5a and 5b can be divided into cases where the signal passes through the attenuator and cases where the signal does not pass through the attenuator depending on the setting of the waveguide switching state, so that it has the function of a step attenuator.

As described above, according to this embodiment, since the connection or non-connection of the attenuator is selected by the waveguide switching device, it is possible to obtain a step attenuator with very high precision. By making it electric, there is an effect that something that can be driven electrically can be obtained.

Furthermore, FIGS. 5 and 6 show other embodiments using this waveguide switching device, and in FIG. 5, the amount of attenuation of the step attenuator can be freely set by making the attenuator variable type 6a. This is how it was done.

In Part 6, a plurality of the circuits shown in Fig. 4 or 5 are connected in series, and by setting the combination of waveguide switch states and the attenuation amount of each attenuator, a multi-stage step attenuator can be created. can be configured.

In the embodiments shown in FIGS. 4 to 6, a waveguide switch is used as the four-terminal switch, but a coaxial switch or the like may also be used.

Furthermore, an answerback signal may be taken out from the waveguide switcher to confirm the switching operation.

It is also possible to use an electric waveguide switching device.

〔Effect of the invention〕

As described above, according to the step attenuator of the present invention, connection or non-connection of the attenuator is selected using a latching circulator or a four-terminal switch, so that the attenuation amount has good reproducibility and is electrically driven. It has the effect of allowing you to get what you can.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a step attenuator according to one embodiment of the present invention, FIGS. 2 and 3 are diagrams showing other embodiments of FIG. 1, and FIG. 4 is a diagram showing another embodiment of the present invention. Figure, 5th
FIG. 6 and FIG. 6 are diagrams showing another embodiment of FIG. 4, and FIG. 7 is a diagram showing a conventional step attenuator. In the figure, ■ is a latching circulator, 2 is an attenuator, 5 is a waveguide switch, and 6 is an attenuator.

Claims (2)

[Claims] (1) In a step attenuator, a latching circulator is used in which a signal is transmitted from terminal 1 to terminal 2 and from terminal 2 to terminal 3 when in state 1, and in a direction opposite to state 1 when in state 2. , an attenuator having one terminal short-circuited and the other terminal connected to any one terminal of the latching circulator, one of the remaining terminals of the latching circulator being used as an input and the other as an output. step attenuator. (2) In a step attenuator, in state 1, terminals 1 and 2 and terminals 3 and 4 are connected, and in state 2, terminals 1 and 4 and terminals 3 and 2 are connected. and an attenuator connected between two terminals connected in either state 1 or state 2 of the 4-terminal switch, the 4-terminal switch A step attenuator characterized in that one of the remaining terminals is used as an input and the other as an output.