JPH04157903A - Dielectric resonator - Google Patents

Abstract

PURPOSE:To increase the conductor area in a limited shape, to reduce the loss and to obtain a high Q by embedding a conductor in an insulation support including a dielectric body and forming the conductor in spiral. CONSTITUTION:Conductors 31,32 are formed in spiral with a dielectric layer 300 inbetween opposite to each other. Most part of the conductors 31,32 is embedded in the inside of an insulation support 30 and sealed by the support 30 as a monolithic structure. The conductor 31 in the two conductors 31,32 is led to cover the surface of the support 30, the conductor 31 is used as a ground conductor to obtain shield action. One side of the conductors 31,32 in the winding axis direction is led to a terminal electrode 41 formed to one end face of the support 30. The other end in the winding axis direction is led to the other end face of the support 30, the end of the conductor 32 is reflected at the end face of the support 30 to form a terminal electrode 42. Thus, the resonator is equivalent to a circuit in which an inductor is connected between the electrodes 41 and 42.

Description

Detailed Description of the Invention <Industrial Application Field> The present invention relates to a dielectric resonator suitable for configuring a voltage controlled oscillator or the like, and relates to a dielectric resonator suitable for configuring a voltage controlled oscillator or the like. By embedding the electrode in a limited shape, the electrode area can be increased, loss can be reduced, and a high Q value can be obtained.

<Prior Art> Dielectric resonators are widely used as components of mobile communication radio equipment such as car telephones, various radio equipment such as mobile phones, and voltage-controlled oscillators incorporated in these. There is. FIG. 11 is a plan view of a conventional coaxial dielectric resonator, and FIG. 12 is a front sectional view thereof. As shown in the figure, the conventional dielectric resonator has a structure in which a conductor 2 is adhered to the inner and outer peripheral surfaces of a cylindrical dielectric 1 made of dielectric ceramic or the like. The conductor 2 is usually formed as a conductor film containing silver as a main component.

<Problem to be solved by the invention> In a dielectric resonator, Q is expressed as Q-(retention energy)/loss. Here, the loss is given by: loss - (conductor loss) + (radiation loss) + (skin loss) + (proximity loss). In other words, once the reactance is determined,
By reducing the loss, Q can be increased.

However, in the conventional coaxial type four-person electric resonator, since the surface area of the conductor 2 is a substantially constant value determined by the surface area of the dielectric 1, there is a limit to the improvement of conductor loss and skin loss. For this reason, it has been difficult to obtain a dielectric resonator with an even higher Q.

Therefore, an object of the present invention is to solve the above-mentioned conventional problems by creating a dielectric resonator that increases the conductor area, reduces loss, and obtains a high Q value within a limited shape. The goal is to provide the following.

<Means for Solving the Problems> In order to solve the above-mentioned problems, a dielectric resonator according to the present invention is a dielectric resonator in which a conductor is embedded inside an insulating support body containing a dielectric material, The conductor is characterized by a spiral shape.

<Operation> Since the conductor has a spiral shape, the conductor area can be increased within a limited shape. Therefore, conductor loss and skin loss are reduced, and a high Q can be obtained.

Moreover, since the conductor is buried inside the insulating support containing the dielectric, it has a monolithic structure with most of the conductor sealed by the insulating support, which has excellent conductor protection, moisture resistance, and durability. A highly reliable dielectric resonator can be obtained.

<Example> FIG. 1 is a front sectional view of a dielectric resonator according to the present invention, and FIG.
The figure is a side view, FIG. 3 is an electrical equivalent circuit diagram, and FIG. 4 is a perspective view of the external appearance. In the figure, 30 is an insulating support made of dielectric ceramic or the like; 31.
32 is a conductor, and 41.42 is a terminal electrode.

The conductors 31 and 32 are formed in a spiral shape and are opposed to each other with the dielectric layer 300 sandwiched therebetween. Therefore, within a limited shape, the conductor area can be increased, conductor loss and skin loss can be reduced, and a high Q can be obtained. Although the illustrated conductors 31 and 32 have a rectangular spiral shape, they may also have a circular spiral shape. The number of turns of the spiral is arbitrary.

Most of the conductors 31, 32 are embedded within the insulating support 30 and are sealed by the insulating support 30, forming a monolithic structure. Therefore, a highly reliable dielectric resonator with excellent conductor protection, moisture resistance, durability, etc. can be obtained.

One of the two conductors 31 and 32 is led out so as to cover the surface of the insulating support 30. Therefore, by using the conductor 31 as a ground conductor, a shielding effect can be obtained. The two conductors 31 and 32 have one end side in the winding axis direction led out to the same position on one end surface of the insulating support 30, and a terminal electrode 41 formed on the one end surface of the insulating support 30.
It is electrically conductive. The other end side in the direction of the winding shaft is led out to the other end surface of the insulating support body 30. The end of the conductor 32 is
It is folded back on the end surface side of the insulating support 30 to form a terminal electrode 42 . Thereby, as shown in FIG. 3, a circuit equivalent to connecting an inductance L between the terminal electrodes 41 and 42 is obtained. Terminal electrode 41 becomes a ground electrode.

FIG. 5 is a diagram showing a method of manufacturing the dielectric resonator shown in the above embodiment. First, as shown in FIG. 5(a), an unfired telephone porcelain sheet 300 having a conductor 31 formed on its surface,
Unfired electric porcelain sheet 30 with conductor 32 formed on the surface
1, the two unfired dielectric ceramic sheets 300 and 301 are superimposed on each other as shown in FIG. 5(b). Next, as shown in FIG. 5(C), both unfired dielectric porcelain sheets 300
．． 301 into a spiral. After that, it is fired and the necessary terminal electrodes are added to complete the process.

6 is a front sectional view of another embodiment of the dielectric resonator according to the present invention, FIG. 7 is a sectional view taken along the line -A6 of FIG. 6A, and FIG. 8 is a sectional view of FIG. A sectional view taken along the line, and FIG. 9 is a perspective view of the external appearance. In the figure, of the two conductors 31 and 32, the conductor 31 is set back by a gap G from the other end side in the winding axis direction or the other end surface of the insulating support, and the conductor 32 is It is led out to the other end surface in the direction of the winding shaft and is electrically connected to the terminal electrode 42.

FIG. 10 is a diagram showing a method of manufacturing the dielectric resonator shown in FIGS. 6 to 9. First, as shown in FIG. 10(a), an unfired dielectric ceramic sheet 300 having a conductor 31 formed on the front surface and a conductor 32 formed on the back surface, and an unfired dielectric sheet 301 are prepared. The conductor 31 is formed so that one end thereof is positioned on the inner side of the gap G from the end edge of the unfired dielectric ceramic sheet 300.

Next, as shown in FIG. 10(b), unfired electric porcelain sheets 300 and 301 are overlapped. After this, Figure 5 (
It is completed by winding it into a spiral as described in C), then firing it, and providing the terminal electrodes 41 and 42.

<Effects of the Invention> As described above, according to the present invention, the following effects can be obtained.

(a) Since the conductor is spiral, it is possible to increase the conductor area within a limited shape, reduce conductor loss and skin loss, and provide a dielectric resonator with a high Q.

(b) Since the conductor is embedded inside the insulating support containing the dielectric, it has a monolithic structure in which the conductor is sealed by the insulating support, resulting in high reliability with excellent conductor protection, moisture resistance, and durability. dielectric resonators are obtained.

(C) It is possible to provide a dielectric resonator that can guarantee sufficient moisture resistance and durability even in wireless communication devices such as car phones, mobile phones, and the like.

[Brief explanation of drawings]

FIG. 1 is a front sectional view of a dielectric resonator according to the present invention, and FIG.
The figure is a side view, FIG. 3 is an electrical equivalent circuit diagram, FIG. 4 is a perspective view of the external appearance, and FIGS.
c) is a diagram showing an example of the manufacturing method, and FIG. 6 is a front sectional view of another embodiment of the dielectric resonator according to the present invention.
7 is a sectional view taken along the line A and -A6 in FIG. 6, FIG. 8 is a sectional view taken along the line A7-A7 in FIG. 11 is a plan view of a conventional coaxial dielectric resonator, and FIG. 12 is a front sectional view thereof. 30...Insulating support 31.31...Conductor 41.42...Terminal electrode Fig. 10 Fig. 11 Fig. 1□-11

Claims (6)

[Claims] (1) A dielectric resonator in which a conductor is embedded inside an insulating support body containing a dielectric material, wherein the conductor has a spiral shape. (2) The dielectric resonator according to claim 1, wherein the conductor includes two conductors facing each other with a dielectric layer interposed therebetween. (3) The dielectric resonator according to claim 2, wherein one of the two conductors is led out so as to cover the surface of the insulating support. (4) One end side of the two conductors in the winding axis direction is led out to the same position on one end surface of the insulating support, and is electrically connected to a terminal electrode formed on the one end surface of the insulating support. The dielectric resonator according to claim 2 or 3, characterized in that: (5) The dielectric resonator according to claim 2, wherein the other end side of the two conductors in the winding axis direction is led out to the other end surface of the insulating support. (6) One of the two conductors is provided so that the other end side in the winding axis direction is set back from the other end face of the insulating support, and the other conductor is led out to the other end face in the winding axis direction. 5. The dielectric resonator according to claim 4, wherein the dielectric resonator is electrically connected to a terminal electrode provided on the other end surface.