KR20000039105A - Dielectric filter - Google Patents

Abstract

PURPOSE: A dielectric filter is provided to positively apply the filter to a circuit by using resonance holes and trim portions. CONSTITUTION: A dielectric body(110) induces electric polarization. The lower surface of the dielectric body(110) has first, second, and third resonance holes(111,112,113) which have a semi-cylindrical shape. A conductive film(120) is coated on all the surface of the dielectric body(110) except for the first, second, and third resonance holes(111,112,113). The inner surfaces of the first, second, and third resonance holes(111,112,113) are grinded to form first, second, and third trim portions(131,132,133). The second trim portion has a variable grinding width(W).

Description

Dielectric filter

The present invention relates to a dielectric filter, and more particularly, a first trim part, a second trim part, and a third trim part having a predetermined capacitance (C _S ) value provided in the dielectric body part to vary the second trim part. The present invention relates to a dielectric filter capable of actively adjusting the spacing between two attenuation poles having an in-grinding width to realize attenuation characteristics in a high range.

Generally, as illustrated in FIGS. 1 and 2, the dielectric filter 10 has a substantially cylindrical first resonance hole 21 and a second resonance hole 22 therein, and is electrically driven by an electric field. An input terminal implemented by partially grinding the dielectric body portion 20 to induce polarization, the conductor coating 30 plated on the surface of the dielectric body portion 20, and the conductor coating 30. 41 and the first terminal 51 and the first terminal having a predetermined capacitance by grinding the inner surface of the output terminal 42 and the first resonance hole 21 and the second resonance hole 22 in a ring shape; It consists of two trim parts 52.

At this time, the first resonant hole 21 and the second resonant hole 22 are horizontally formed in the longitudinal direction of the dielectric body portion 20 and vertically formed through the same diameter up and down, the first resonant hole ( 21) and the inner circumference of the second resonator hole 22 is plated with a conductor coating 30, which is partially cut into a ring shape through grinding processing, and thus the first trim portion 51 and The second trim 52 is implemented.

In general, the diameters of the first resonant hole 21 and the second resonant hole 22 have an inductance, and the conductor coating is formed from the inner circumference of the first resonant hole 21 and the second resonant hole 22. The distance to 30 has a capacitance, and the first trim portion 51 and the second trim portion 52 generally have a coupling capacitance.

The frequency attenuation characteristic through the dielectric filter 10 configured as described above is that one attenuation pole in the high range is formed as shown in FIG. 3 to eliminate unnecessary signals and noise signals.

However, the dielectric filter 10 for obtaining a desired band signal through one attenuation pole as described above has a large disadvantage in that the attenuation characteristic in the high range is too sensitive and adversely affects the desired band signal.

In addition, in the dielectric filter 10 according to the related art, since the first resonance hole 21 and the second resonance hole 22 maintain vertical horizontal spacing in the longitudinal direction of the inside of the dielectric body part 20, they are vertically penetrated. It is very difficult to form the first resonant hole 21 and the second resonant hole 22, and the grinding work of the first trim part 51 and the second trim part 52 is difficult, and the volume thereof is too large. There was a downside.

Therefore, in recent years, the structure of the dielectric filter has been improved to overcome the disadvantages described above. The improved structure will now be described with reference to FIGS. 4 to 7.

4 is a perspective view showing a dielectric filter developed in recent years, FIG. 5 is an equivalent circuit diagram showing a dielectric filter developed in recent years, FIG. 6 is a graph showing frequency attenuation characteristics to which a dielectric filter developed in recent years is applied, and FIG. 7. Is a use state diagram showing a dielectric filter developed in recent years.

As shown in FIG. 3, the recently developed dielectric filter 100 has a rectangular parallelepiped dielectric body part 110 for inducing electrical polarization and parallel spaced at equal intervals from a lower surface of the dielectric body part 110. The first resonance groove 111, the second resonance groove 112, the third resonance groove 113, and the first resonance groove except for the lower surface of the dielectric body part 110. Conductor coating 120 plated on all surfaces including the 111 and the second resonance grooves 112 and the third resonance grooves 113, the first resonance grooves 111 and the second resonance grooves 112, One inner circumferential edge of the third resonator groove 113 is ground in an arc shape to thereby form a first trim part 131, a second trim part 132, and a third trim part 133 having a predetermined capacitance C _S. ) And the surfaces of both edge portions of the dielectric body portion 110, which are respectively opposed to the first trim portion 131 and the third trim portion 133, have a rectangular band shape. It consists of an input terminal 141 and an output terminal 142 implemented by partial grinding.

Here, the diameters of the inner circumferences of the first resonance groove 111, the second resonance groove 112, and the third resonance groove 113 have an inductance, and the first resonance groove 111 and the third resonance groove The distance from the inner circumference of the 113 to the input terminal 141 and the output terminal 142 has a capacitance, and the first trim 131, the second trim 132, the third trim 133 ) Has a coupling capacity.

In this case, an equivalent circuit diagram as shown in FIG. 4 may be implemented through mutual induction of the first resonance groove 111, the second resonance groove 112, and the third resonance groove 113. Frequency attenuation characteristics through the circuit diagram are as shown in FIG.

That is, as shown in FIG. 6, the recently developed dielectric filter 100 is provided with two attenuation poles in the high range to easily remove unnecessary signals and noise signals. Through the frequency attenuation characteristics, the attenuation variation in the high range can be made insensitive, thereby minimizing the adverse effect on the pass band of the desired signal frequency.

On the other hand, the dielectric body portion 110 exposed on the lower surface of the dielectric filter 100 is easy to change characteristics by an external electromagnetic field, and may adversely affect other circuit elements, which has been recently developed. As shown in FIG. 7, the lower surface of the dielectric filter 100 is mounted on the circuit board so that the bottom surface of the dielectric filter 100 is directly contacted with each other, and is fixed to each other by soldering through the input terminal 141 and the output terminal 142. Rather, it can be seen that the effect of the external electromagnetic field can be minimized and the size of the dielectric filter 100 can be minimized.

However, as described above, the dielectric filter 100 for obtaining only a desired band signal through two attenuation poles has a useful function, but the attenuation characteristics in the high range are fixed, that is, due to two attenuation poles. Since the attenuation band is fixed, there is a big disadvantage that the passband of the desired frequency signal cannot be actively implemented.

Accordingly, the present invention has been made to solve the above-mentioned problems, and the object of the present invention is to provide a first trim part and a second trim part, which are provided in the dielectric body part and have a predetermined capacitance (C _S ) value, It is useful for a circuit requiring various filtering characteristics by adjusting the grinding width of the second trim part of the third trim part to be variable so as to actively adjust the spacing of two attenuation poles to realize the attenuation characteristic in the high range. It is to provide a dielectric filter that can be applied.

1 is a perspective view showing a dielectric filter according to the prior art.

2 is a cross-sectional view showing a dielectric filter according to the prior art.

Figure 3 is a graph showing the frequency attenuation characteristics to which the dielectric filter according to the prior art.

4 is a perspective view showing a dielectric filter recently developed.

Fig. 5 is an equivalent circuit diagram showing a dielectric filter recently developed.

Figure 6 is a graph showing the frequency attenuation characteristics to which a dielectric filter developed in recent years.

7 is a use state diagram showing a dielectric filter developed in recent years.

8 is a perspective view showing a dielectric filter according to the present invention;

9 is a graph showing the frequency attenuation characteristics to which the dielectric filter according to the present invention is applied.

* Description of the symbols for the main parts of the drawings *

100 dielectric filter 110 dielectric body portion

111: first resonance groove 112: second resonance groove

113: third resonance groove 120: conductor coating

131: first trim part 132: second trim part

133: third trim portion 141: input terminal

142: output terminal

The present invention for achieving the above object, the first resonant groove and the second resonant groove, the third resonant shape formed in a semi-cylindrical shape spaced parallel to each other at equal intervals on the lower surface of the rectangular body portion of the rectangular parallelepiped to induce electrical polarization, A conductor coating plated on all surfaces including the resonance groove, the first resonance groove, the second resonance groove, and the third resonance groove except for the lower surface of the dielectric body, the first resonance groove and the second resonance groove; 3. A dielectric filter including a first trim part, a second trim part, and a third trim part having a predetermined capacitance C _S by grinding an inner circumference of a third resonant groove in an arc shape, wherein the second resonant groove is provided. The second trim having a predetermined capacitance (C _S ), which is ground in an arc shape around the inner periphery of the second trim part, actively adjusts the spacing of two attenuation poles to realize attenuation characteristics at high frequencies. The basic characteristic of the technical configuration is that it has a variable grinding width so that the passband width of the signal frequency can be arbitrarily adjusted.

Hereinafter, a preferred embodiment of the dielectric filter according to the present invention will be described with reference to FIGS. 8 and 9.

8 is a perspective view illustrating a dielectric filter according to the present invention, and FIG. 9 is a graph showing frequency attenuation characteristics to which the dielectric filter according to the present invention is applied.

As shown in FIG. 8, the dielectric filter 100 according to the present invention has a rectangular parallelepiped dielectric body part 110 for inducing electrical polarization and parallel to the bottom surface of the dielectric body part 110 at equal intervals. The first resonance grooves are spaced apart and recessed in a semi-cylindrical shape except for the first resonance groove 111, the second resonance groove 112, the third resonance groove 113, and the lower surface of the dielectric body 110. The conductor coating 120 plated on all surfaces including the groove 111, the second resonance groove 112, and the third resonance groove 113, and the first resonance groove 111 and the second resonance groove 112. The first trim part 131 and the second trim part 132 and the third trim part having a predetermined capacitance C _S by grinding the inner circumferential edge of one side of the third resonance groove 113 in an arc shape. 133 and the surfaces of both edge portions of the dielectric body portion 110 positioned opposite to the first trim portion 131 and the third trim portion 133, respectively, in a rectangular band shape. Composed of an input terminal 141 and output terminal 142 it is implemented by part of the grinding process.

Here, the diameters of the inner circumferences of the first resonance groove 111, the second resonance groove 112, and the third resonance groove 113 have an inductance, and the first resonance groove 111 and the third resonance groove The distance from the inner circumference of the 113 to the input terminal 141 and the output terminal 142 has a capacitance, and the first trim 131, the second trim 132, the third trim 133 ) Has a coupling capacity.

In addition, the second trim part 132 having a predetermined capacitance C _S having a predetermined capacitance C _S by grinding the inner circumference of the second resonant groove 112 has two attenuations to realize attenuation characteristics at a high frequency. It is desirable to have a structure having a variable grinding width W so as to actively adjust the interval l of the pole so that the passband width of the desired signal frequency can be arbitrarily adjusted.

At this time, through the mutual induction action of the first resonance groove 111, the second resonance groove 112, the third resonance groove 113 to remove the unnecessary noise signal as shown in Figure 9 and the signal of the desired frequency It has the attenuation characteristic of passing the bay.

Here, as shown in FIG. 9, when the gap ℓ of two attenuation poles shown in solid lines is narrowed, the grinding width W of the second trim part indicated by solid lines is narrow as shown in FIG. 8. In the case of the attenuation characteristic and the spacing (l ^' ) of two attenuation poles shown by the dotted line as shown in FIG. 9 is wide, the grinding width (W ^') of the second trim part indicated by the dotted line as shown in FIG ^. A) is attenuated in the case of being wide, so that the variable attenuation characteristic can be realized by adjusting the grinding width (W) of the second trim part, thereby being actively used in a circuit requiring various filtering characteristics.

As described above, according to the dielectric filter 100 according to the present invention, the first resonance groove 111 and the second resonance recessed and molded into a semi-cylindrical shape in parallel spaced at equal intervals on the lower surface of the dielectric body part 110. The first trim part 131, the second trim part 132, and the third trim having a predetermined capacitance C _S value implemented by grinding the groove 112 and the inner circumference of the third resonant groove 113. Of the two attenuation poles to implement the attenuation characteristics in the high range by making the second trim portion 132 provided at the inner circumference of the second resonance groove 132 of the section 133 to have a variable grinding width (W) By actively adjusting the interval (l), it is possible to arbitrarily adjust the passband width of the desired signal frequency, which has an excellent effect that can be actively used in a circuit requiring various filtering characteristics.

Claims (1)

The first resonant groove 111 and the second resonant groove 112 and the third resonant shape formed in a semi-cylindrical shape spaced apart at equal intervals on the lower surface of the rectangular parallelepiped dielectric body part 110 for inducing electric polarization. Plated on all surfaces including the first resonance groove 111, the second resonance groove 112, and the third resonance groove 113 except for the resonance groove 113 and the lower surface of the dielectric body part 110. Grinding the inner circumference of the conductor coating 120, the first resonance groove 111, the second resonance groove 112, and the third resonance groove 113 in an arc shape to obtain a predetermined capacitance value C _S. In the dielectric filter comprising a first trim 131, a second trim 132, a third trim 133 having, The second trim 132 having a predetermined capacitance C _S having a predetermined capacitance C _S by grinding the inner circumference of the second resonant groove 112 has two attenuation poles for realizing attenuation characteristics at high frequencies. And a variable grinding width (W) so as to actively adjust the interval (l) to arbitrarily adjust the passband width of the desired signal frequency.