JPH06268418A - Voltage controlled resonator - Google Patents

Abstract

PURPOSE:To make a constitution compact and simple by connecting an inside conductor through a capacity between a conductive pin inserted into the round hole of a dielectric and the inside conductor at which the round hole is formed with a variable capacitive element. CONSTITUTION:A sleeve 4 of the dielectric made of Teflon is interfit into the round hole formed at the ceramics of a conductive resonator 1. One end of a conductive pin 5 is inserted into the sleeve 4, the capacity is formed between the pin 5 and an inside conductor la of the resonator 1, and the other end of the pin 5 is connected with a varactor diode 2. Therefore, the compact wiring connection of the resonator with the variable capacitive element can be attained, and it is possible to make the constitution compact and simple without having an inverse influence on the characteristic.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a voltage controlled resonator using a TEM mode rectangular dielectric resonator.

[0002]

2. Description of the Related Art When a voltage control filter (VCF) capable of controlling a frequency in a pass band by an applied voltage is used in a tuner of a general high frequency equipment, as shown in FIG. 6, a metal copper plate is used as a resonance element. Stator 2
I am using 1. That is, in this voltage control filter, by arranging a plurality of stators 21 to form a bandpass filter of a plurality of stages, by connecting a varactor diode 12 which is a variable capacitance element to one end of each stator 21,
The frequency applied to the varactor diode 12 can control the frequency of the pass band.

However, for example, satellite communication (VSA)
The transmission converter in the outdoor unit of the ground station for T) requires a voltage control filter in the 3 GHz band, but if the stator 21 is used, the filter operation cannot be performed because the frequency is too high. .

Therefore, it is conceivable to use a dielectric resonator as the voltage control filter used in such an extremely high frequency band. This dielectric resonator has been conventionally used as a resonant element of a voltage-controlled oscillator (VCO) in which a varactor diode is connected to form a voltage-controlled resonator. In some cases, the dielectric resonators are coupled in multiple stages and used as a bandpass filter. Therefore, by coupling the dielectric resonators in which the varactor diodes are connected to the dielectric resonators in a plurality of stages, it is possible to configure a voltage control filter that can be used in an extremely high frequency band.

[0005]

By the way, it is necessary to interpose a capacitance between the dielectric resonator and the varactor diode in the above voltage controlled resonator. Therefore, in the conventional voltage controlled resonator, as shown in FIG. 7, the dielectric resonator 11 is arranged on the substrate 13, and the electrode 18 attached to the inner conductor 11a of the dielectric resonator 11 and the substrate 13 are arranged. The capacitor 19 and the varactor diode 12 mounted in the above were connected via the wiring pattern 17.

However, in such a conventional voltage-controlled resonator, the wiring length from the inner conductor 11a of the dielectric resonator 11 to the varactor diode 12 via the capacitor 19 becomes too long, so that it is used as a resonant element. The characteristics are deteriorated and a large mounting area is occupied.
Then, if the voltage control filter is configured by coupling the conventional voltage control resonators in a plurality of stages, not only the sufficient characteristics as a bandpass filter cannot be obtained, but also it is difficult to downsize the filter element. Problems also arise.

[0007]

In order to solve the above-mentioned problems, the present invention is a TEM in which a circular hole is formed through a square pole-shaped dielectric and an inner conductor is provided on the inner peripheral surface of the circular hole. Insert one end side of a rod-shaped conductor pin from one end face on the center axis of the dielectric resonator and the circular hole of this dielectric, and form a predetermined capacitance between this conductor pin and the inner conductor of the circular hole. Then
A feature is that a variable capacitance element is connected to the other end side of the conductor pin.

In addition to the above-mentioned main structure, a dielectric resonator is a half wavelength type in which an outer conductor is formed only on the side surface of a dielectric quadrangular prism shape, and a dielectric resonator is a dielectric material. There is a one-quarter wavelength type in which an outer conductor is formed on one end surface and the other end surface of the square prism shape. Further, in addition to any of these configurations, a sleeve made of resin such as Teflon is fitted into the round hole of the dielectric of the dielectric resonator, and the conductor pin is inserted substantially on the central axis of the sleeve. Is characterized by.

In addition to any one of these structures, one end of the conductor pin has a length equal to 2 of the total length of the circular hole of the dielectric of the dielectric resonator.
Inserted up to a length less than one-third, and a plurality of dielectric resonators are arranged side by side, and
Also disclosed are those dielectric resonators in which a window portion through which the dielectric is exposed is provided in a part of the outer conductors on the overlapped side surfaces.

[0010]

According to the voltage-controlled resonator described above, the capacitance between the conductor pin inserted in the round hole of the dielectric and the inner conductor formed on the inner peripheral surface of the round hole causes the dielectric resonator to pass through. Since the inner conductor and the variable capacitance element are coupled, the dielectric resonator and the variable capacitance element can be connected and wired without using a capacitor as a circuit component.

As a result, since the connection between the dielectric resonator and the variable capacitance element can be made compact, the characteristics of the voltage controlled resonator are not adversely affected, and the size of the voltage controlled resonator can be reduced. You will be able to contribute.

A half with an open space between the inner conductor and the outer conductor
A wavelength (λ / 2) type dielectric resonator, or a quarter wavelength (λ /
4) Type dielectric resonator or the like can be arbitrarily selected.

When a Teflon sleeve is used as a support material for the conductor pin inserted into the circular hole of the dielectric of the dielectric resonator, the capacitance formed between the inner conductor and the conductor pin is Teflon as the dielectric. Affected by the dielectric constant of.

In the inner conductor of the dielectric resonator, the closer to the open end face of the dielectric, the larger the amplitude due to the TEM mode, and particularly in the half-wave type, the position of half the total length of the round hole. Vibration disappears. Therefore, it is suitable to insert the conductor pin to a length of less than half the total length of the round hole.

When the voltage-controlled resonator of the present invention is used as a voltage-controlled filter, it is necessary to couple the voltage-controlled resonators through a plurality of stages through capacitors to increase the selectivity, and also to control the voltage of each stage. By coupling the resonator through the window provided on the outer conductor of the dielectric resonator, it is not necessary to use a capacitor as a circuit component.

[0016]

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

1 to 5 show an embodiment of the present invention. FIG. 1 is a vertical sectional view of a voltage controlled resonator, FIG. 2 is a schematic perspective view of the voltage controlled resonator, and FIG. FIG. 4 is a schematic perspective view of the voltage control filter, and FIG. 5 is a circuit diagram of the voltage control filter.

In the voltage controlled resonator of this embodiment, as shown in FIG. 3, a varactor diode 2 is connected to one end of the inner conductor 1a of the dielectric resonator 1 via a capacitor C1. The varactor diode 2 is a variable capacitance element whose capacitance changes according to the applied voltage, and the voltage VB is applied via the coil L as shown in the figure. A capacitor C2 is connected to the other end of the inner conductor 1a. Therefore, a resonance circuit is formed between the terminal on the other end side of the capacitance C2 and the ground, and the capacitance of the varactor diode 2 is changed by adjusting the voltage VB, so that the resonance frequency of the voltage controlled resonator falls within a predetermined range. Can be set arbitrarily.

As shown in FIG. 2, the dielectric resonator 1 is made of a quadrangular prism-shaped ceramic metallized with silver foil. Ceramics is a dielectric material obtained by sintering barium titanate or the like in a block shape, and has round holes penetrating both end faces of a quadrangular prism shape. The metallization with silver foil is formed by applying a silver paste on the surface of the ceramic and firing it. Then, as shown in FIG. 1, the metallization applied to the inner peripheral surface of the round hole becomes the inner conductor 1a, and the metallization applied to all side surfaces of the quadrangular prism shape becomes the outer conductor 1b. Since the half-wavelength (λ / 2) type dielectric resonator 1 is shown here, both end faces of the quadrangular prism-shaped ceramic are open without being metallized. However, in the case of the quarter wavelength (λ / 4) type, one end face is also metalized to short-circuit the inner conductor 1a and the outer conductor 1b.

The dielectric resonator 1 is mounted and mounted on a substrate 3, as shown in FIG. In the round hole formed in the ceramic of this dielectric resonator 1, the sleeve 4
Has been inserted. The sleeve 4 is a dielectric made of Teflon. One end of the conductor pin 5 is inserted into the sleeve 4 from one end on the central axis. The conductor pin 5 is
It is a rod-shaped metal conductor that is thinner than the sleeve 4. Half
In the inner conductor 1a of the wavelength type dielectric resonator 1,
Since the vibration disappears at a position of ½ of the total length of the round hole, the insertion length of the conductor pin 5 is set to be less than ½ of the total length of the round hole. In addition, the other end of the sleeve 4 is also inserted with an end portion of an L-shaped conductor fitting 6 having a short length on the central axis.

The other end of the conductor pin 5 projecting from the sleeve 4 is soldered to one lead wire of the varactor diode 2 mounted vertically on the substrate 3. The other lead wire of the varactor diode 2 is passed through the through hole of the substrate 3 and soldered to the wiring pattern 7 on the back surface side. Further, the other end of the conductor fitting 6 protruding from the sleeve 4 is also passed through the through hole of the substrate 3 and soldered to another wiring pattern 7 on the back surface side.

The voltage controlled resonator having the above-mentioned structure is provided with the sleeve 4
The capacitance C1 shown in FIG. 3 is formed between the conductor pin 5 inserted at one end and the inner conductor 1a of the dielectric resonator 1. A capacitance C2 shown in FIG. 3 is formed between the conductor fitting 6 inserted into the other end of the sleeve 4 and the inner conductor 1a of the dielectric resonator 1. These capacitances C1 and C2 are the insertion length of the conductor pin 5 and the conductor fitting 6, the difference between the outer diameter of the conductor pin 5 and the conductor fitting 6 and the outer diameter of the sleeve 4 (the inner diameter of the round hole), and the dielectric constant of the sleeve 4. And are set to have appropriate sizes. The coil L
Although not shown in FIGS. 1 and 2, is separately connected to one lead wire of the varactor diode 2.

With the above structure, the voltage controlled resonator of this embodiment can form the capacitance C1 and the capacitance C2 without using a capacitor as a circuit component, so that the space between the dielectric resonator 1 and the varactor diode 2 can be reduced. The connection wiring can be shortened, the characteristics of the voltage controlled resonator are not adversely affected, and the size of the voltage controlled resonator can be reduced.

A voltage control filter using the voltage control resonator shown in FIGS. 1 to 3 is shown in FIGS.

This voltage control filter is a combination of the above voltage control resonators in four stages as shown in FIG. The voltage controlled resonators are coupled by connecting the inner conductor 1a of the dielectric resonator 1 at the other end side via the capacitance C3. However, here, as shown in FIG. 4, the respective side faces of the four dielectric resonators 1 are arranged side by side to couple each stage. That is, each of the dielectric resonators 1 has a window portion 1c where the outer conductor 1b is not metallized on a part of its side surface.
Are formed, and the windows 1c are arranged so as to overlap each other. Therefore, each dielectric resonator 1 has the window portion 1
The electromagnetic waves leaking through c couple to each other, and a capacitance C3 shown in FIG. 5 is formed between them. The window 1c can be easily formed by partially providing a metal mask when the silver paste is applied to the side surface of the ceramic.

This voltage control filter is a band pass filter having a high selectivity formed by coupling the above voltage control resonators in a plurality of stages. The dielectric resonator 1 and the varactor of each voltage control resonator are constituted. Since the connection between the diode 2 and the like can be shortened, a small band pass filter with good characteristics can be obtained. Further, since each voltage controlled resonator is coupled through the window portion 1c of the dielectric resonator 1, the capacitance C
It is not necessary to use the capacitor of the circuit component as 3.

[0027]

As is apparent from the above description, according to the present invention, it is possible to compactly connect and connect the dielectric resonator and the variable capacitance element, so that the characteristics of the voltage controlled resonator are adversely affected. In addition to this, it becomes possible to contribute to the miniaturization of this voltage controlled resonator.

[Brief description of drawings]

1 is a longitudinal sectional view of a voltage controlled resonator according to an embodiment of the present invention.

FIG. 2 shows an embodiment of the present invention and is a schematic perspective view of a voltage controlled resonator.

FIG. 3 shows an embodiment of the present invention and is a circuit diagram of a voltage controlled resonator.

FIG. 4 shows an embodiment of the present invention and is a schematic perspective view of a voltage control filter.

FIG. 5 is a circuit diagram of a voltage control filter according to an embodiment of the present invention.

FIG. 6 shows a conventional example and is a schematic perspective view of a voltage control filter using a stator.

FIG. 7 shows a conventional example and is a vertical cross-sectional view of a voltage-controlled resonator using a dielectric resonator.

[Explanation of symbols]

 1 Dielectric resonator 1a Inner conductor 1b Outer conductor 1c Window part 2 Varactor diode 4 Sleeve 5 Conductor pin C1 Capacitance

Claims (4)

[Claims] 1. A dielectric resonator in a TEM mode in which a circular hole penetrating a rectangular prism-shaped dielectric is formed, and an inner conductor is provided on an inner peripheral surface of the circular hole, and a circular hole of the dielectric is formed. One end side of the rod-shaped conductor pin is inserted from one end face on the central axis, a predetermined capacitance is formed between this conductor pin and the inner conductor of the round hole, and a variable capacitance element is connected to the other end side of the conductor pin. Voltage controlled resonator. 2. A sleeve made of a resin such as Teflon is fitted in a round hole of a dielectric of a dielectric resonator, and a conductor pin is inserted substantially on the central axis of the sleeve. 1. The voltage controlled resonator according to 1. 3. A conductor pin according to claim 1, wherein one end of the conductor pin is inserted to a length less than one half of the total length of the circular hole of the dielectric body of the dielectric resonator. The voltage-controlled resonator described. 4. A plurality of dielectric resonators in the voltage controlled resonator according to any one of claims 1 to 3 are arranged side by side so that the side surfaces overlap each other, and the dielectric resonators overlap each other. A voltage controlled resonator, wherein a window portion through which a dielectric is exposed is provided in a part of the outer conductors on the combined side surfaces.