KR101782948B1 - Dielectric filter - Google Patents

Abstract

A dielectric filter is disclosed. The dielectric filter of the present invention comprises: a dielectric block including a top surface, a bottom surface facing the top surface, and a side surface connecting the top surface and the bottom surface; at least one resonance hole passing through the dielectric block between the top surface and the bottom surface; at least one transmission line hole passing through the dielectric block between the top surface and the bottom surface, and positioned adjacent to the resonance hole; an external conductor continuously formed on the top surface, the bottom surface, and the side surface; an input and output electrode formed on the bottom surface, and separated from the external conductor; a resonance hole internal conductor formed inside the resonance hole, and electrically connected to the external conductor on the bottom surface; a transmission line hole internal conductor formed inside the transmission line hole, and electrically connected to the input and output electrode on the bottom surface; a resonance hole conductor pattern formed on the top surface, and electrically connected to the resonance hole internal conductor on the top surface; and a transmission line hole conductor pattern formed on the top surface, and electrically connected to the transmission line hole internal conductor on the top surface. The resonance hole conductor pattern, the transmission line hole conductor pattern, and the external conductor are separated from each other by a non-conductor area on the outer surface of the dielectric block. The dielectric filter according to an embodiment of the present invention operates in a very high frequency band, is short in the length of the through hole, and easy to be mounted on the PCB.

Description

Dielectric filter {DIELECTRIC FILTER}

The present invention relates to a dielectric filter, and more particularly, to a dielectric filter having frequency selectivity including a plurality of resonance holes passing through a dielectric block.

As the mobile communication technology develops, the frequency used increases. The use of higher frequency bands makes it possible to utilize the optical bandwidth, and it is possible to transmit more data at higher speed. In the conventional second generation mobile communication, a frequency band of 1 GHz or less is mainly used. In recent 3 < nd > generation and 4th generation mobile communication, a frequency band of 2 GHz to 3 GHz is used. It is known that the 5th generation mobile communication to be commercialized will utilize the centimeter wave and the millimeter wave, which corresponds to a high frequency band of 3 GHz to 30 GHz and 30 GHz to 300 GHz.

The monoblock type dielectric filter forms a plurality of resonance holes in the dielectric block and controls the electrical characteristics between the resonance holes to realize frequency selectivity. Here, the length of the resonance hole is determined by the frequency band in which the dielectric filter is used. As the frequency band used increases, the length of the resonance hole becomes shorter, which enables miniaturization of the dielectric filter. However, since the length of the resonance hole is very short when the frequency band of 3 GHz or more is reached, there is a problem that the dielectric filter is mounted on the PCB.

FIG. 1 shows one form of a conventional dielectric filter. Referring to FIG. 1, an input / output terminal 12 mounted on a PCB is formed on a side surface of the dielectric block 10. In the dielectric filter of Fig. 1, the resonance hole 11 has a length of several centimeters, so that a sufficient lateral area is secured for mounting. Therefore, the input / output terminal 12 can be mounted on the side surface. Further, the input / output terminal 12 can be formed with a sufficient area. As a result, the coupling between the input / output terminal 12 and the resonance hole 11 can be generated to some extent.

However, if the dielectric filter is designed to operate in a very high frequency band, the length of the resonance hole is only a few millimeters to a few tens of millimeters, and the area of the side surface becomes very narrow. It is very difficult to mount such a narrow side face to the PCB. Further, if the input / output terminal is formed on such a narrow side, sufficient coupling between the resonance hole and the filter can not be ensured, and the performance of the filter is deteriorated.

Therefore, there is a demand for a dielectric filter of a very high frequency band in which mounting performance and filter performance are ensured.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a dielectric filter that operates in a very high frequency band and is easy to mount on a PCB while having a short through hole.

Further, the present invention provides a dielectric filter designed to generate a proper coupling between an input / output terminal and a resonance hole.

According to an aspect of the present invention, there is provided a dielectric filter including a dielectric block including an upper surface, a lower surface facing the upper surface, and a side surface connecting the upper surface and the lower surface, At least one resonance hole, at least one transmission line hole penetrating the dielectric block between the upper surface and the lower surface and positioned adjacent to the resonance hole, an outer conductor formed continuously to the upper surface, the lower surface, and the side surface, An input / output electrode formed on the bottom surface and separated from the outer conductor, a resonance hole internal conductor formed inside the resonance hole and electrically connected to the external conductor on the bottom surface, A transmission line hole internal conductor electrically connected to the input / output electrode on the lower surface, And a transmission line hole conductor pattern formed on the upper surface and electrically connected to the transmission line hole internal conductor on the upper surface, wherein the resonance hole conductor pattern is electrically connected to the resonance hole internal conductor on the surface of the resonance hole, Pattern, the transmission line via conductor pattern, and the external conductor are separated from each other by the non-conductor area on the outer surface of the dielectric block.

In one embodiment of the present invention, the dielectric block is formed in a hexahedron shape, and the side surface is composed of a seat surface, a right surface, a front surface, and a rear surface, and the resonant hole and the transmission line hole are arranged in a left- The conductor may be elongated in the left-right direction at a portion of the upper surface in contact with the front surface and the rear surface.

In one embodiment of the present invention, the conductive cover may further include a conductor cover electrically connected to the outer conductor formed on the upper surface, the conductor cover being spaced apart from the resonant hole conductor pattern and the transmission line conductor pattern.

In one embodiment of the present invention, the conductor cover may include a cover portion facing away from the upper surface, and a support portion extending from the both ends of the cover portion, the support portion being electrically connected to an outer conductor formed on the upper surface, have.

In one embodiment of the present invention, the non-conductor region may extend from the upper surface to the lower surface through the left and right surfaces, and may separate the outer conductor and the input / output electrode from the lower surface.

In one embodiment of the present invention, the height between the upper and lower surfaces of the dielectric block may be shorter than the width between the front and rear surfaces and the length between the left and right surfaces.

In one embodiment of the present invention, the transmission line hole may be formed to be smaller than the resonance hole.

In one embodiment of the present invention, a plurality of the resonance holes are formed in one direction, and two transmission line holes may be formed at both ends of the resonance hole.

In one embodiment of the present invention, the transmission line through-hole conductor pattern may be formed to be biased in the direction of one adjacent resonance hole with respect to an electrically connected transmission line hole.

In one embodiment of the present invention, the input / output electrode may be formed to abut the side surface at the lower surface.

The dielectric filter according to an embodiment of the present invention operates in a very high frequency band, so that it is easy to mount the dielectric filter on the PCB while the length of the through hole is short.

Also, the dielectric filter according to an embodiment of the present invention is advantageously designed to generate a proper coupling between the input / output terminal and the resonance hole.

FIG. 1 shows one form of a conventional dielectric filter.
2 is a perspective view of a dielectric filter according to an embodiment of the present invention.
3 is a bottom perspective view of a dielectric filter according to an embodiment of the present invention.
4 is a perspective view of a dielectric filter according to another embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In describing the present invention, if it is judged that adding a detailed description of a technique or a configuration already known in the field can make the gist of the present invention unclear, some of it will be omitted from the detailed description. In addition, terms used in the present specification are terms used to appropriately express the embodiments of the present invention, which may vary depending on the person or custom in the relevant field. Therefore, the definitions of these terms should be based on the contents throughout this specification.

Hereinafter, a dielectric filter according to an embodiment of the present invention will be described with reference to FIGS. 2 to 3 attached hereto.

2 is a perspective view of a dielectric filter according to an embodiment of the present invention. 3 is a bottom perspective view of a dielectric filter according to an embodiment of the present invention.

2 and 3, the dielectric filter of the present invention includes a dielectric block 100, a resonance hole 110, a transmission line hole 120, an external conductor 130, an input / output electrode 140, A transmission line hole conductor pattern 121, a resonance hole conductor pattern 113, a transmission line conductor pattern 123, and a non-conductor area 150. [

Hereinafter, the respective constituent elements constituting the dielectric filter will be described in detail.

The dielectric block 100 is formed in a block shape having an upper surface and a lower surface. The upper and lower surfaces of the dielectric block 100 are opposed to each other and include side surfaces connecting the upper surface and the lower surface. The dielectric block 100 is formed, for example, in a substantially hexahedral shape, so that the side surfaces can be configured as four surfaces of a seat surface, a right surface, a front surface, and a rear surface. Although the dielectric block 100 is shown in the form of a rectangular parallelepiped, the present invention is not limited thereto. A ceramic material, an alumina material, or the like. The dielectric block 100 is preferably formed of a material having a relative dielectric constant of 3.5 or more.

The dielectric block 100 may be a non-directional device, and may have a different name designating each surface depending on the viewing direction and the type of the dielectric filter installed. Therefore, in this specification, the two surfaces through which the through-hole penetrates through the dielectric block 100 will be referred to as an upper surface and a lower surface. Specifically, the upper surface is a surface on which a conductor pattern is formed in the vicinity of the through hole, and the inner conductor of the resonance hole 110 is a surface shorted to the outer conductor 130. The side connecting the upper surface and the lower surface is referred to as a side surface, and the seating surface, the right surface, the front surface, and the rear surface are defined based on the fact that the plurality of through holes are arranged in the left-right direction.

In the dielectric block 100, the space between the upper and lower surfaces is referred to as a height, the space between the right and left surfaces is referred to as a length, and the space between the front and rear surfaces is referred to as a width. The dielectric block 100 of the present invention is formed to have a height shorter than the width and the length. Thus, if the length of the dielectric block 100 is shortened, the height of the side surface becomes short, and the area of the side surface becomes narrow.

The dielectric block 100 is formed with a plurality of through holes passing between the upper surface and the lower surface. It is preferable that the through hole penetrates the inside of the dielectric in a direction orthogonal to the upper surface and the lower surface. The plurality of through holes are arranged in one direction in the dielectric block 100. [ For example, as shown in FIG. 2, the plurality of through holes may be arranged in the left-right direction of the dielectric block 100.

The through hole may be divided into a resonance hole 110 and a transmission line hole 120. The resonance hole 110 means a through hole serving as a resonator in the dielectric filter and the transmission line hole 120 means a through hole electrically connected to the input / output electrode 140 of the dielectric filter. However, the transmission line hole 120 may function as a resonator between the resonance hole 110 and the external conductor 130 or the like.

Typically, the transmission line holes 120 are disposed at both ends of the resonance hole 110, respectively. A plurality of resonance holes 110 are arranged in one direction between the transmission line holes 120 at both ends. Although not shown in the accompanying drawings, a resonance hole for shunt zero may be additionally formed outside the transmission line hole as the case may be.

The resonance hole 110 functions as a resonator in the dielectric filter. The length of the resonance hole 110 corresponds to the height of the dielectric block 100. As described above, if the height of the dielectric block 100 is short, the length of the resonance hole 110 is also shortened correspondingly. The length of the resonance hole 110 is determined in proportion to a wavelength of a signal to be used. The short resonance hole 110 may be designed for use in a signal in a high frequency band or a very high frequency band.

The transmission line hole 120 is typically disposed at each end of the resonance hole 110, and is connected to the input / output electrode 140, which will be described later. The transmission line hole 120 may be formed as a hole smaller than the resonance hole 110.

An outer conductor 130 is formed on a part of the outer surface of the dielectric block 100. The outer conductor 130 is specifically formed on each of the top, bottom, and sides of the dielectric block 100. More specifically, the outer conductor 130 may be formed only on the front and rear surfaces of the side surface of the dielectric block 100. The outer conductor 130 may be elongated in the left-right direction at a portion of the upper surface of the dielectric block 100 abutting the front and rear surfaces. The external conductor 130 may be formed on the lower surface of the dielectric block 100 except for the input / output electrode 140 and the non-conductor region 150, which will be described later. The external conductors 130 formed on the top, bottom, and side surfaces may be formed continuously.

The non-conductor region 150 is a portion of the outer surface of the dielectric block where the outer conductor 130 is not formed. Specifically, the non-conductor region 150 may be formed on a part of the upper surface of the dielectric block 100, a part of the lower surface, and a part of the lower surface. The non-conductor region 150 separates the outer conductor 130 from the conductor pattern. In addition, the non-conductor region 150 separates a plurality of conductor patterns. The non-conductor region 150 separates the external conductor 130 from the input / output electrode 140.

The input / output electrodes 140 are formed on the lower surface of the dielectric block 100. The input / output electrode 140 is electrically connected to the internal conductor 121 through a transmission line, which will be described later, on the lower surface of the dielectric block 100. The input / output electrode 140 is separated from the lower surface of the dielectric block 100 by the outer conductor 130 and the non-conductor region 150.

The input / output electrode 140 may be formed to abut the side surface at the bottom surface. Specifically, the input / output electrode 140 may be formed at a portion where the input / output electrode 140 abuts the left and right surfaces at the lower surface. The non-conductor region 150 separating the input / output electrode 140 and the outer conductor 130 may be continuous in the right and left sides. As described above, when the input / output electrode 140 is formed to be in contact with the side surface, it is easy to form solder for mounting. In addition, there is an advantage that the parasitic capacitance of the dielectric filter with the resonator by the solder can be minimized.

The input / output electrode 140 is a portion electrically connected to the terminal of the circuit board when the dielectric filter of the present invention is mounted on the circuit board. Accordingly, the surface on which the input / output electrode 140 is formed is brought into contact with the circuit board, and in the present invention, the lower surface of the dielectric block 100 comes into contact with the circuit board. As described above, when the height of the dielectric block 100 is short, the side surface area of the dielectric block 100 becomes narrow and it is difficult to mount the circuit block on the circuit board. In this case, the surfaces that can be used as the mounting surface are the upper surface and the lower surface. On the upper surface, conductor patterns 113 and 123, which will be described later, are formed.

An internal conductor is formed inside the through hole. The inner conductor formed inside the resonance hole 110 is referred to as a resonator hole inner conductor 111 and the inner conductor formed inside the transmission line hole 120 is referred to as a transmission line hole inner conductor 121. [

The resonator hole internal conductor 111 is formed on the entire inner surface of the resonance hole 110. The inner conductor 111 of the resonance hole may be electrically connected to the resonance hole conductor pattern 113 at a portion contacting the upper surface. In addition, the inner conductor 111 of the resonance hole may be electrically connected to the outer conductor 130 at a portion contacting the lower surface.

The transmission line hole internal conductor 121 is formed on the entire inner surface of the transmission line hole 120. The transmission line hole internal conductor 121 may be electrically connected to the transmission line via conductor pattern 123 at a portion contacting the upper surface. In addition, the transmission line hole internal conductor 121 may be electrically connected to the input / output electrode 140 at a portion contacting the lower surface.

The conductor pattern is an electrode formed around the opening on the upper surface side of the through hole. A conductor pattern formed around the upper surface of the resonance hole 110 is referred to as a resonance hole conductor pattern 113 and a conductor pattern formed around the upper surface of the transmission line hole 120 is referred to as a transmission line conductor pattern 123 .

The resonance hole conductor pattern 113 is electrically connected to the inner conductor of the resonance hole 110. It is preferable that the resonance hole conductor pattern 113 is formed separately from other adjacent resonance hole conductor patterns 113. Although it is preferable that the resonance hole conductor pattern 113 be separated from the external conductor 130, some resonance hole conductor patterns 113 may be connected to the external conductor 130 as occasion demands. In the accompanying drawings, the resonance hole conductor pattern 113 is shown as being separated from the outer conductor 130 with the non-conductor region 150 therebetween.

The transmission line via conductor pattern 123 is electrically connected to the inner conductor of the transmission line hole 120. The transmission line via conductor pattern 123 is preferably formed separately from the adjacent resonance hole conductor pattern 113.

The transmission line via conductor pattern 123 may be formed to be offset in the direction of one adjacent resonance hole 110 with respect to the transmission line hole 120 electrically connected thereto. More specifically, the conductor pattern of the transmission line hole 120 formed at the left end is formed to be deviated to the right with reference to the top opening of the transmission line arc, and the conductor pattern of the transmission line hole 120 formed at the right end is formed And may be formed to be deviated to the left with respect to the upper surface opening. The shape of the transmission line through-hole conductor pattern 123 is advantageous in that parasitic capacitance with other electric elements that can be disposed adjacent to the dielectric filter can be minimized.

Hereinafter, a dielectric filter according to another embodiment of the present invention will be described with reference to FIG. 4 is a perspective view of a dielectric filter according to another embodiment of the present invention.

This embodiment is characterized in that a conductor cover is further combined in the dielectric filter described above with reference to Figs. Therefore, for convenience of description, the present embodiment will be described while focusing on differences from the above embodiment.

Referring to FIG. 4, a conductor cover 160 is coupled to an upper surface of the dielectric block 100. The conductor cover 160 is formed of a conductive metal. The conductor cover 160 includes a cover portion 161 and a support portion 162.

The cover portion 161 is opposed to the upper surface of the dielectric block 100. The cover portion 161 is formed to face most of the upper surface of the dielectric block 100. In particular, the cover portion 161 may be formed to face the conductor patterns formed on the upper surface of the dielectric block 100.

The support portion 162 is formed by bending at both ends of the cover portion 161. Specifically, the support portion 162 may be formed by bending the front and rear ends of the cover portion 161. [ The lower end of the support portion 162 may be electrically connected to the external conductor 130. Specifically, the lower end of the support portion 162 may be coupled to an outer conductor formed to be long in the left-right direction at a portion abutting the front and rear surfaces of the upper surface. The lower end of the support portion 162 and the external conductor 130 may be electrically connected by solder (not shown) or the like.

The conductor cover 160 can suppress inadvertent coupling within the dielectric filter or between the dielectric filter and other external electrical components. In addition, the conductor cover 160 can contribute to improving the RF performance of the dielectric filter, such as improving the attenuation characteristics of the attenuation region of the dielectric filter.

The embodiments of the dielectric filter of the present invention have been described above. The present invention is not limited to the above-described embodiments and the accompanying drawings, and various modifications and changes may be made by those skilled in the art to which the present invention pertains. Therefore, the scope of the present invention should be determined by the equivalents of the claims and the claims.

100: dielectric block
110: resonance hole 111: resonance hole inner conductor
113: resonance hole conductor pattern
120: transmission line hole 121: transmission line hole internal conductor
123: transmission line via conductor pattern
130: outer conductor
140: input / output electrode
150: non-conductor region
160: conductor cover 161: cover portion
162: Support

Claims (10)

A dielectric block including an upper surface, a lower surface facing the upper surface, and a side surface connecting the upper surface and the lower surface;
At least one resonance hole passing through the dielectric block between the upper surface and the lower surface;
At least one transmission line hole passing through the dielectric block between the upper surface and the lower surface and positioned adjacent to the resonance hole;
An outer conductor continuously formed on the upper surface, the lower surface, and the side surface;
An input / output electrode formed on the lower surface and separated from the external conductor;
A resonance hole internal conductor formed inside the resonance hole and electrically connected to the external conductor at the lower surface;
A transmission line hole internal conductor formed inside the transmission line hole and electrically connected to the input / output electrode at the lower surface;
A resonance hole conductor pattern formed on the upper surface and electrically connected to the conductor inside the resonance hole on the upper surface; And
And a transmission line hole conductor pattern formed on the upper surface and electrically connected to the transmission line hole internal conductor on the upper surface,
Wherein the resonant hole conductor pattern, the transmission line via conductor pattern, and the outer conductor are separated from each other by a non-conductor area on an outer surface of the dielectric block.
The method according to claim 1,
Wherein the dielectric block is formed in a hexahedron shape and the side surface is composed of a seat surface, a right surface, a front surface, and a rear surface,
The resonance hole and the transmission line hole are arranged in the left-right direction,
Wherein the outer conductor is elongated in the left-right direction at a portion of the upper surface that abuts the front surface and the rear surface.
3. The method of claim 2,
And a conductor cover electrically connected to the outer conductor formed on the upper surface and spaced apart from and opposed to the resonant hole conductor pattern and the transmission line conductor pattern.
The method of claim 3,
Wherein the conductor cover includes a cover portion facing away from the upper surface, and a support portion bent and extending at both ends of the cover portion and having a lower end electrically connected to an external conductor formed on the upper surface.
3. The method of claim 2,
And the non-conductor region extends from the upper surface to the lower surface via the left and right surfaces, and separates the external conductor and the input / output electrode from the lower surface.
3. The method of claim 2,
Wherein the dielectric block has a height between the upper and lower surfaces that is shorter than a width between the front and rear surfaces and between the left and right surfaces.
The method according to claim 1,
And the transmission line hole is formed to be smaller than the resonance hole.
The method according to claim 1,
Wherein a plurality of the resonance holes are formed in one direction,
And two transmission line holes are formed at both ends of the resonance hole.
The method according to claim 1,
Wherein the transmission line via conductor pattern is biased in the direction of one adjacent resonance hole with respect to an electrically connected transmission line hole.
The method according to claim 1,
And the input / output electrode is formed to abut the side surface at the lower surface.

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