WO2009082053A1

WO2009082053A1 - Dielectric-composite-type, high-sensitive resonator without radiation loss

Info

Publication number: WO2009082053A1
Application number: PCT/KR2008/000668
Authority: WO
Inventors: Kie-Jin Lee; Jong-Chel Kim; Seung-Wan Kim; Hee-Kyun Lee
Original assignee: Industry-University Cooperation Foundation Sogang University
Priority date: 2007-12-26
Filing date: 2008-02-04
Publication date: 2009-07-02
Also published as: KR20090069895A; KR100954801B1

Abstract

The present invention relates to a dielectric-composite-type resonator. The dielectric-composite-type resonator comprises: a plurality of dielectric blocks bonded in a row through each bonding surface; dielectric blocks for electrode positioned at both ends among the plurality of bonded dielectric blocks; electrodes each formed at bottom surfaces of the dielectric blocks for electrode; and a coating layer formed by coating all surfaces of each dielectric block and the bonding surfaces with a conductive material, excepting for an insulating region to insulate the electrodes, each bonding surface being formed of a first coating region coated with the conductive material and a first non-coating region not coated with the conductive material.

Description

DIELECTRIC-COMPOSITE-TYPE, HIGH-SENSITIVE RESONATOR WITHOUT

RADIATION LOSS

FIELD OF THE INVENTION The present invention relates to a dielectric resonator, and in particular to a dielectric-composite-type resonator without radiation loss having a plurality of blocks bonded thereto.

DESCRIPTION OF THE RELATED ART A dielectric-composite-type resonator, which is an electronic device using dielectric resonance characteristic, has been widely used as a component of an RF device such as a communication unit and a repeater. The most representative electronic device using the dielectric-composite-type resonator is a filter. The filter has excellent resonance characteristics and withstands against high operating power, as compared to a filter using a general LC circuit.

Describing the aforementioned filter with reference to FIG. 4, in the case of a dielectric ceramic filter 100, a plurality of vertical grooves 102 are formed on both sides of a dielectric block 101 along a longitudinal direction. Four surfaces other than both sections of the dielectric block 101 are coated with a conductive material. The dielectric block 101 with such a structure is mounted on a substrate 103 on which a microstrip line 104s are installed. Meanwhile, both sections of the dielectric block 101 are formed with electrodes 105 connected to the microstrip lines 104 for an input/output of signals. Also, in both sections of the dielectric block 101, metal patterns 106 are formed around the electrodes 105. In such a structure, a depth D or a width W of the vertical groove 102 is changed so that the resonance frequency of the dielectric ceramic filter 100 can be precisely controlled to a desired frequency.

And, a dielectric block including a dielectric block generating norch, which is further bonded to both sections of the dielectric block 101, has been developed.

However, it is expected that the dielectric ceramic filter 100 shown in FIG. 3 has disadvantages of a processing difficulty, an increase in size of the entire dielectric block 101 and an increase in damage by external force, due to a formation of the vertical groove 102. Also, in both sections of the dielectric ceramic filter 100, radiation loss of field occurs between the electrode 105 and the microstrip 104.

And, the dielectric block including the further bonded dielectric block generating the norch has problems in that the interference phenomenon occurs and the norch generating performance is slightly degraded, due to a reflected wave generated from the further bonded dielectric block. Throughout this application, several patents and publications are referenced and citations are provided in parentheses. The disclosure of these patents and publications is incorporated into this application in order to more fully describe this invention and the state of the art to which this invention pertains.

DETAILED DESCRIPTION OF THIS INVENTION

The present invention proposes to solve the problems. It is an object of the present invention to provide a dielectric-composite-type resonator that is easily manufactured, becomes small in the entire size, and has excellent mechanical strength.

Also, it is another object of the present invention to provide a dielectric- composite-type resonator with excellent band characteristics by preventing degradation of band pass characteristics according to a norch resonance. In order to achieve the technical problems, there is provided a dielectric- composite-type resonator, comprising: a plurality of dielectric blocks bonded in a row through each bonding surface; dielectric blocks for electrode positioned at both ends among the plurality of bonded dielectric blocks; electrodes each formed at bottom surfaces of the dielectric blocks for electrode; and a coating layer formed by coating all surfaces of each dielectric block and the bonding surfaces with a conductive material, excepting for an insulating region formed in a predetermined regions around the electrodes to insulate the electrodes, each bonding surface being formed of a first coating region coated with the conductive material and a first non-coating region not coated with the conductive material.

The first non-coating region traverses a top side and a bottom side of the bonding surface and is formed in a previously defined shape.

Also, the dielectric-composite-type resonator further comprises a dielectric block for norch bonded to one side of the dielectric block for electrode. The bonding surface for norch of the dielectric block for electrode and the dielectric block for norch is configured of a second coating region coated with the conductive material and a second non-coating region not coated with the conductive material. The shape and size of the second non-coating region are changed to be smaller than those of the second coating region, thereby reducing the reflected wave generated from the dielectric block for norch. For example, the bottom side of the second non-coating region contacts the bottom surface of the dielectric block for electrode and the height of the second non-coating region may be formed to be smaller than that of the second coating region.

The shape of the dielectric block for electrode is changed to be smaller than the dielectric block for norch, thereby enhancing attenuation for a specific frequency region by the dielectric block for norch. For example, the width size in a longitudinal direction and a vertical direction of the dielectric block for electrode may be changed so that its top surface is a regular square.

The electrode includes a hole formed on the bottom surface of the dielectric block for electrode; and an electrode unit formed by coating a region positioned between the hole and the insulating region and all regions inside the hole with the conductive material.

Also, the dielectric-composite-type resonator according to the present invention can be easily manufactured, be small in the entire size, and have the reinforced mechanical intensity by bonding the plurality of dielectric blocks through the bonding surface.

Also, the dielectric-composite-type resonator according to the present invention makes the output signals approximately symmetrical based on the resonance frequency by the first non-coating region optimized and can minimize the reflection loss at the resonance frequency. Also, since the dielectric-composite-type resonator according to the present invention of which the electrode is positioned at a center, not an edge as in the electrode of the conventional monoblock dielectric resonator and is configured of the hole electrode, it can reduce the damage such as the separation of the electrode from the dielectric block and can be used for high power, even when the input/output signal is large.

Also, the dielectric-composite-type resonator according to the present invention can minimize the reflected wave from the dielectric block for norch by the second non- coating region and enhance the band pass characteristics according to the norch resonance by the adjustment of the shape of the dielectric block for electrode. Also, the dielectric-composite-type resonator according to the present invention can be variously applied to the electronic device such as the filter. BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. Ia to Ic each is a perspective view, a top view, a bottom view for a dielectric-composite-type resonator according to a first embodiment of the present invention, FIG. Id is a cross-sectional view taken along line A-A of FIG. Ib, and FIG. Ie is a cross-sectional view taken along line B-B of FIG. Ic;

FIGS. 2a to 2c each is a perspective view, a top view, and a bottom view for a dielectric-composite-type resonator according to a second embodiment of the present invention, FIG. 2d is a cross-sectional view taken along line A-A of FIG. 2b, FIG. 2e is a cross-sectional view taken along line B-B of FIG. 2b, and FIG. 2f is a cross-sectional view taken along line C-C of FIG. 2c;

FIGS. 3a to 3c each is a perspective view, a top view, a bottom view for a dielectric-composite-type resonator according to a third embodiment of the present invention, FIG. 3d is a cross-sectional view taken along line A-A of FIG. 3b, FIG. 3e is a cross-sectional view taken along line B-B of FIG. 3b, and FIG. 3f is a cross-sectional view taken along line C-C of FIG. 3c;

FIG. 4 is a perspective view schematically showing a conventional dielectric ceramic filter;

FIG. 5a is a frequency response graph for the conventional dielectric ceramic filter shown in FIG. 4;

FIG. 5b is a frequency response graph for the dielectric-composite-type resonator according to the first embodiment shown in FIG. Ia;

FIG. 5c is a frequency response graph for the dielectric-composite-type resonator according to the second embodiment shown in FIG. 2a; and FIG. 5d is a frequency response graph for the dielectric-composite-type resonator according to the third embodiment shown in FIG. 3a. DESCRIPTION FOR KEEY ELEMENTS IN THE DRAWINGS>

1: Dielectric-composite-type resonator

10: Bonding surface 11: First coating region

12: First non-coating region

20: Dielectric blocks

21: Dielectric block

22: Dielectric block for electrode 30: Electrode

31: Hole

32: Electrode unit

40: Coating layer

50: Insulating region 60: Dielectric block for norch

70: Bonding surface for norch

71: Second coating region

72: Second non-coating region

The present invention will now be described in further detail by examples. It would be obvious to those skilled in the art that these examples are intended to be more concretely illustrative and the scope of the present invention as set forth in the appended claims is not limited to or by the examples.

EXAMPLES Hereinafter, the configuration and operation of a dielectric-composite-type resonator according to an exemplary embodiment of the present invention will be described with reference to the accompanying drawings.

<First embodiment

FIG. Ia to Ic each is a perspective view, a top view, a bottom view for a dielectric-composite-type resonator according to a first embodiment of the present invention, FIG. Id is a cross-sectional view taken along line A-A of FIG. Ib, and FIG. Ie is a cross-sectional view taken along line B-B of FIG. Ic. As shown in FIGS. Ia to Ie, the dielectric-composite-type resonator 1 according to the first embodiment includes each bonding surface 10, a plurality of dielectric blocks 20, electrodes 30, a coating layer 40, and an insulating region 50.

A schematic configuration of the dielectric-composite-type resonator 1 according to the first embodiment will be described. As shown in FIG. Ia, the plurality of dielectric blocks 20 are serially connected through each bonding surface 10 and the electrodes 30 each is formed on the bottom surfaces (see FIG. Ic) of dielectric blocks for electrode 22. The coating layer 40 is formed by coating all surfaces of the dielectric block 20 and the bonding surfaces with a conductive material, excepting for the insulating region (see 31 of FIG. Id) for insulating the electrode 30, wherein each bonding surface 10 is configured of a first coating region (see 41 of FIG. Id) coated with the conductive material and a first non- coating region (see 42 of FIG. Id) not coated with the conductive material, as shown in a dashed line in FIG. Ia. The respective dielectric blocks 20 are coupled to each other through the first non-coating region (see 42 of FIG. Id) to perform a function as the dielectric-composite-type resonator 1. Each component of the dielectric-composite-type resonator 1 according to the first embodiment will be described.

First, the bonding surface 10 indicates three surfaces to which four dielectric blocks 20 are mutually bonded, as shown in FIG Ia. The bonding surface 10 is configured of a first coating region 11 coated with the conductive material and a first non-coating region 12 not coated with the conductive material as shown in FIG. Id.

The first coating regions 11 are made of the conductive material and are formed in a quadrangle that is symmetrical to each other, with putting a second coating region therebewteen. The first coating region largely performs two roles; firstly, a role of firmly bonding the dielectric blocks 20 to each other and secondly, a role of controlling frequency band characteristics of a desired signal.

In other words, the shape and size of the first non-coating region 12 are properly designed according to the frequency of pass band, making it possible to obtain the pass band characteristics of the desired signal. Those skilled in the art may calculate the numerical values for the shape and size of the first non-coating region 11 through a discontinuity analysis, etc. Therefore, the description thereof will be omitted.

Although the dielectric blocks 20 are firmly bonded through the first coating region 11, the first non-coating regions 12 cannot perfectly electrically be bonded to each other due to the thickness of the first coating region 11. The first embodiment considers the bonding between the firs non-coating regions 12. The first non-coating region 12 may be made of the same material as the dielectric block 20. It can be considered that the shape may be formed by making the dielectric material into a liquid state and an organic matter or the dielectric material is deposited by a sputtering method. Lead (Pb) may be used as the conductive material. This is because it has low melting temperature and is inexpensive material. The conductive material is not necessarily limited to lead (Pb), but the same conductive material as the coating layer

40 may be used.

The first non-coating region 12 maximally approaches the first coating region

11 of other dielectric blocks 20 by the bonding of the first coating regions 11. The size and shape of the first non-coating region 12 are changed by the size and shape of the first coating region 11, wherein the frequency band characteristics of the desired signal can be controlled according to the size and shape of the first coating region 11.

Herein, the shape of the first non-coating region 12 may be variously formed in O, α,

Il , etc. Next, the plurality of dielectric blocks 20 are bonded through each bonding surface 10 as shown in FIG. Ia. Both ends of the plurality of dielectric blocks bonded in a row are positioned with the dielectric blocks for electrode. The dielectric blocks for electrode have the same composition and shape as the other dielectric blocks 20.

However, a difference from the other dielectric blocks 20 is that the electrodes 30 are formed on the bottom surfaces of the dielectric blocks 22 for each electrode.

As a material of the dielectric block 20, a material with high dielectric constant, low dielectric loss, and temperature coefficient of stabilized resonance frequency is selected. Herein, the dielectric block 20 may use a (Zr, Sn)TiO4- based dielectric material. In the first embodiment, the four dielectric blocks 20 are coupled, but the number of the dielectric blocks 20 may be variously prepared. In other words, five, six or more dielectric blocks can be used according to the frequency band characteristics to be implemented.

Next, the electrode 30 is formed on the bottom surface of the dielectric block for electrode 22. Generally, the input electrode 30 for receiving the signals to be processed and the output electrode 30 for outputting the processed signals are formed at both ends thereof, respectively.

Herein, the electrode 30 is configured of a hole 31 and an electrode unit 32 as shown in FIG. Ie. The hole 31 is formed on the bottom surface of the dielectric block for electrode 22 and the electrode unit 32 is formed by coating an region positioned between the hole 31 and the insulating region 50 and all regions inside the hole 31 with the conductive material. Herein, the pass bandwidth can be finely controlled by changing a depth of the holde 31.

Next, the coating layer 40 is formed by coating all surfaces of each dielectric block 20 and the aforementioned bonding surface 10 with the conductive material, excepting for the insulating region (see 50 of FIG. Ie) for insulating the electrode 30.

Herein, the conductive material is a material with high conductivity such as silver (Ag) or aluminum (Al), etc. and is coated on an outer surface of the dielectric block 20 by a sputtering vacuum deposition, etc. Thereby, the coated dielectric block 20 may perform a function as the dielectric resonator.

Hereinafter, the effects of the first embodiment will be described with reference to the drawing.

FIG. 5a schematically shows frequency response characteristics for the conventional monoblock dielectric resonator 100 shown in FIG. 4. FIG. 5b shows estimated frequency response characteristics for the dielectric-composite-type resonator 1 according to the first embodiment shown in FIG. Ia. Herein, SIl means a magnitude of reflection loss returned to an input stage and S21 means a magnitude of signal output to an output stage.

The graph shown in FIG. 5b is a graph under the assumption that the size and shape of the first non-coating region 12 is adjusted to an optimal dimension in the signal bandwidth of about 1.75GHz to 1.8GHz for clearly explaining the effects of the first embodiment.

The output signal of the conventional monoblock dielectric resonator 100 shown in FIG. 4 is asymmetrical at the left and right of the pass band frequency unlike FIG. 5. In other words, the output signal is asymmetrical based on the resonance frequency. Also, the signal (i.e., reflection loss) returned to the input stage at the resonance frequency is relatively large as about -1OdB. On the other hand, the output signal of the dielectric-composite-type resonator 1 according to the first embodiment is approximately symmetrical based on the resonance frequency shown in FIG. 5b and its reflection loss is equal to or larger than -40dB(sign b) at the resonance frequency.

Also, the dielectric-composite-type resonator 1 according to the first embodiment controls the depth of the hole 31, making it possible to finely control the pass bandwidth of the filter. In other words, as the depth of the hole 31 is deep, the bandwidth is finely increased and as the depth of the hole 31 is shallow, the bandwidth is finely reduced.

Also, since the electrode 30 is positioned at a center, not an edge as in the electrode 1 of the conventional monoblock dielectric resonator 100, the damage such as the separation of the electrode from the dielectric block can be reduced. Therefore, the dielectric-composite-type resonator 1 according to the first embodiment can be used for high power.

<Second embodiment

As shown in FIGS. 2a to 2f, the dielectric-composite-type resonator 1 according to a second embodiment of the present invention includes each bonding surface 10, the plurality of dielectric blocks 20, the electrodes 30, the coating layer 40, the insulating region 50, a dielectric block 60 for norch, and a bonding surface 70 for norch.

A schematic configuration of the dielectric-composite-type resonator 1 according to the second embodiment will be described. As shown in FIG. 2a, the plurality of dielectric blocks 20 are serially connected through each bonding surface 10 and the electrodes 30 each is formed on the bottom surfaces (see FIG. 2c) of the dielectric blocks 22 for electrode. The coating layer 40 is formed by coating all surfaces of the dielectric blocks 20 and the bonding surfaces 10 with the conductive material, excepting for the insulating region (see 31 of FIG. 2f) for insulating the electrode 30. And, the dielectric block 60 for norch is bonded to one side of the dielectric block for electrode 22 through the bonding surface 70 for notch.

Herein, the dielectric block 60 for notch generates norch at desired specific frequency.

Each component of the dielectric-composite-type resonator 1 according to the second embodiment will be described. The description duplicated with the first embodiment will be omitted.

The description of the bonding surface 10, the plurality of dielectric blocks 20, the electrode 30, the coating layer 40, and the insulating region 50 is the same as the first embodiment.

First, the dielectric block 60 for norch is bonded to the one side of the dielectric block for electrode 22 as shown in FIG. 2a. Herein, the dielectric block 60 for norch has a form bonded to a side in a longitudinal direction extended in a straight line, however, can be bonded to another side of the dielectric block for electrode 22. Generally, the dielectric block 60 for norch is operated as a narrow band removing filter and provides sharply attenuating characteristic at the desired specific frequency. The dielectric block 60 for norch is already known and therefore, the concrete description thereof will be omitted.

Next, the bonding surface 70 for norch is a bonding surface of the dielectric block for electrode 22 and the dielectric block 60 for norch. The bonding surface 70 for norch is configured of a second coating region 71 coated with the conductive material and a second non-coating region 72 not coated with the conductive material. Herein, the second coating region is formed of the conductive material as shown in FIG. 2e and has a B shape surrounding the second non-coating region 72. The second coating region 71 mainly performs two roles; firstly, firmly bonding the dielectric block for electrode 22 and the dielectric block 60 for norch to each other and secondly, reducing the reflected wave generated by the dielectric block 60 for norch. In other words, the reflected wave generated by the dielectric block 60 for norch is adjusted according to the shape and size of the second non-coating region 72. Herein, the bottom side of the second non-coating region 72 is bonded to the bottom side of the dielectric block for electrode 22 and the height of the second non-coating region 72 may be formed to be smaller than that of the second coating region 71. In other words, the shape and size of the second non-coating region 72 may properly optionally be designed according to the frequency of the reflected wave.

This design can be made through discontinuity interpretation, etc. by those skilled in the art in a technical field such as microwave engineering and therefore, the detailed description thereof will be omitted. Although the dielectric block for electrode 22 and the dielectric block 60 for norch are firmly bonded through the second coating region 71, the second non- coating regions 72 cannot electrically perfectly be bonded to each other because of the thickness of the second coating region 71. The second embodiment considers the bonding between the second non-coating regions 72. The second non-coating region 72 can be formed of the same dielectric material as the dielectric block 20. The dielectric material may be formed into an organic matter or a liquid state or may be deposited through a sputtering.

Herein, the conductive material of the second coating region 71 may use lead (Pb). This is because lead has low melting temperature and is inexpensive. The conductive material is not necessarily limited to lead, but the same conductive material as the coating layer 40 may be used.

Herein, the second non-coating region 72 is approached to the second coating region 71 of another dielectric block 20 as closely as possible by the bonding of the second coating region 71. The shape and size of the second non-coating region 72 are changed by the size and shape of the second coating region 71. Hereinafter, the effects of the second embodiment will be described with reference to the drawings.

The dielectric-composite-type resonator 1 according to the second embodiment may show the frequency characteristic as shown in FIG. 5c. In order to clearly explain the effects of the second embodiment, a graph shown in FIG. 5c is a graph assuming that when a signal bandwidth is about 2.3GHz to 2.35GHz, the size and shape of the second non-coating region 72 are adjusted to an optimal dimension.

As shown in FIG. 5c, the reflection loss at resonance frequency is reduced to about -6OdB (sign c) by the second non-coating region 72. This is reduced more than about -4OdB (see a sign c of FIG. 5b) by the first embodiment. Therefore, the effect of the reflected wave by the dielectric block 60 for norch may be reduced more than the first embodiment. Also, the norch (sign d) may be formed in a desired frequency region of an output signal S21 by the dielectric block 60 for norch bonded to the one side of the electrode dielectric block 20.

With the aforementioned second embodiment, the effect of generating the norch obtained by the addition of the dielectric block 60 for norch as well as the effect of reducing the reflected wave can be expected.

<Third Embodiment

FIGS. 3a to 3c each is a perspective view, a top view, a bottom vifew for a dielectric-composite-type resonator according to a third embodiment of the present invention, FIG. 3d is a cross-sectional view taken along line A-A of FIG. 3b, FIG. 3e is a cross-sectional view taken along line B-B of FIG. 3b, and FIG. 3f is a cross-sectional view taken along line C-C of FIG. 3c;

As shown in FIGS. 3a to 3f, the dielectric-composite-type resonator 1 includes each bonding surface 10, the plurality of dielectric blocks 20, the electrode 30, the coating layer 40, the insulating region 50, the dielectric block 60 for norch, and the bonding surface for norch 70, likewise the second embodiment.

A schematic configuration of the dielectric-composite-type resonator 1 according to the third embodiment will be described.

As shown in FIG. 3a, the plurality of dielectric blocks 20 are serially connected through each bonding surface 10 and the electrodes 30 each is formed on the bottom surfaces (see FIG. 3c) of the dielectric blocks 22 for electrode. The coating layer 40 is formed by coating all surfaces of the dielectric blocks 20 and the bonding surfaces 10 with the conductive material, excepting for the insulating region (see 31 of FIG. 2f) for insulating the electrode 30. And, the dielectric block 60 for norch is bonded to one side of the dielectric block for electrode 22 through the bonding surface 70 for notch.

Herein, the dielectric block 60 for notch generates norch at desired specific frequency. Each component of the dielectric-composite-type resonator 1 according to the third embodiment will be described. The description duplicated with the first and second embodiments will be omitted.

The description of the bonding surface 10, the plurality of dielectric block 20, the electrode 30, the coating layer 40, the insulating region 50, the dielectric block 60 for norch, and the bonding surface 70 for norch is the same as the second embodiment

The feature of the third embodiment different from the second embodiment is that the shape of dielectric block for electrode 22 is changed as shown in FIG. 3a. Herein, the width size in a vertical direction (sign D of FIG. 3a) of the dielectric block for electrode 22 is reduced. The width sizes in a longitudinal direction and a vertical direction of the dielectric block for electrode may be changed so that its top surface is a regular square. The norch phenomenon by the dielectric block 60 for norch can be enhanced by the change. Those skilled in the art in a technical field such as microwave engineering may calculate the numerical values for the concrete dimensions of the dielectric block for electrode through a discontinuity analysis, etc. and therefore, the description thereof will be omitted.

The dielectric-composite-type resonator 1 according to the third embodiment may show the frequency characteristics as shown in FIG. 5d. The graph shown in FIG. 5d is a graph under the assumption that the size and shape of the dielectric block for electrode 22 and the second non-coating region 12 are an optimal dimension in the case of the signal bandwidth of about 2.3GHz to 2.35GHz for clearly explaining the effects of the third embodiment. The dielectric-composite-type resonator 1 according to the third embodiment can enhance the norch (sign f) by the dielectric block 60 for norch as shown in FIG. 5d. (sign e), which is an effect by the second non-coating region 72 shown in FIG. 3e, is a feature of the aforementioned second embodiment.

< Application form> The following embodiment is an application form of the first to third embodiments.

The dielectric-composite-type resonator 1 according to the application form is provided by coupling the microstrip line substrate to the bottom side of the dielectric- composite-resonator 1 according to the aforementioned embodiments. Herein, the microstrip line may be provided in a similar form to the conventional microstrip line substrate 100 shown in FIG. 4.

The microstrip line substrate according to the application form includes the input line and the output line electrically connected to the aforementioned electrodes 30, respectively. Herein, the input line and the output lines is required to be extended to the center of the electrode dielectric block 20, unlike the conventional input/output line 104. This is because the electrode of the first to third embodiments is disposed at the center of the electrode dielectric block 20.

Therefore, the microstrip line substrate according to the application form coats the surfaces of the input line and the output line formed at the bonding surface with the composite-type dielectric block 20 with the insulating film, making it possible to insulate the coating layer 40 and the input line and the output line. Herein, the application form may further include a connection pin that electrically connects the electrode 30 to the input line and the output line. Thereby, the electrical connection of the electrode 30 and the input line and the output line can be more enhanced. As in the aforementioned application form, the dielectric-composite-type resonator can be applied to various electronic elements, such as a filter, etc. The dielectric-composite-type resonator, which is an electronic element using dielectric resonance characteristic, can be used in the part industry, such as communication equipment and repeaters.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventions. Thus, it is intended that the present invention covers the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.

Having described a preferred embodiment of the present invention, it is to be understood that variants and modifications thereof falling within the spirit of the invention may become apparent to those skilled in this art, and the scope of this invention is to be determined by appended claims and their equivalents.

Claims

What is claimed is:

1. A dielectric-composite-type resonator, comprising: a plurality of dielectric blocks bonded in a row through each bonding surface; dielectric blocks for electrode positioned at both ends among the plurality of bonded dielectric blocks; electrodes each formed at bottom surfaces of the dielectric blocks for electrode; and a coating layer formed by coating all surfaces of each dielectric block and the bonding surfaces with a conductive material, excepting for an insulating region formed in a predetermined regions around the electrodes to insulate the electrodes, each bonding surface being formed of a first coating region coated with the conductive material and a first non-coating region not coated with the conductive material.

2. The dielectric-composite-type resonator according to claim 1, wherein the first non- coating region traverses a top side and a bottom side of the bonding surface and is formed in a previously defined shape.

3. The dielectric-composite-type resonator according to claim 1, further comprising a dielectric block for norch bonded to one side of the dielectric block for electrode.

4. The dielectric-composite-type resonator according to claim 3, wherein the bonding surface for norch of the dielectric block for electrode and the dielectric block for norch is configured of a second coating region coated with the conductive material and a second non-coating region not coated with the conductive material.

5. The dielectric-composite-type resonator according to claim 4, wherein the shape and size of the second non-coating region are changed to be smaller than those of the second coating region.

6. The dielectric-composite-type resonator according to claim 5, wherein the bottom side of the second non-coating region contacts the bottom surface of the dielectric block for electrode and the height of the second non-coating region is formed to be smaller than that of the second coating region.

7. The dielectric-composite-type resonator according to claim 3, wherein the shape of the dielectric block for electrode is changed to be smaller than the dielectric block for norch, thereby enhancing attenuation for a specific frequency region by the dielectric block for norch.

8. The dielectric-composite-type resonator according to claim 7, wherein the width size in a longitudinal direction and a vertical direction of the dielectric block for electrode is changed so that its top surface is a regular square.

9. The dielectric-composite-type resonator according to claim 1, wherein the electrode includes: a hole formed on the bottom surface of the dielectric block for electrode; and an electrode unit formed by coating a region positioned between the hole and the insulating region and all regions inside the hole with the conductive material.