KR100213387B1 - Simple type mono-block dielectric filter - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an integrated dielectric filter. In particular, in an integrated dielectric block having a through hole formed to penetrate back and forth, the coupling capacitance and the input / output capacitance can be easily adjusted and the structure is simplified. It relates to a dielectric filter.

According to the dielectric filter according to the present invention, it is possible to easily adjust the coupling capacitance and the input / output capacitance in an integrated dielectric block having a coaxial through hole formed to penetrate the front and rear surfaces, and to secure sufficient bandwidth. In addition, since the structure of the dielectric block can be simplified and easily manufactured, mass productivity is improved.

Description

Integrated dielectric filter with simple structure

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an integrated dielectric filter. In particular, in an integrated dielectric block having coaxial through-holes formed therein, the coupling capacitance and the input / output capacitance are easily adjusted, and the structure is simplified. The present invention relates to an integrated dielectric filter having a simple structure to improve mass productivity.

In general, a coaxial dielectric filter is used in mobile communication equipment such as a car phone or a mobile phone using a high frequency range (300 MHz ~ several kilohertz). The first dielectric filter used in such a mobile communication device is a portable and mobile convenience. It is desirable to be as small and lightweight as possible, secondly, impact resistance is required, and thirdly, a bandwidth of 20-30 MHz is required.

1 is a perspective view of a conventional dielectric filter. Referring to FIG. 1, in the conventional dielectric filter of FIG. 1, a conductive electrode is formed inside two through holes 1a and 1b in a rectangular parallelepiped dielectric block 1. The electrode is coupled between the conductor electrodes by a coupling hole 1d in which no electrode is formed. The dielectric filter component having such a structure includes two resonator through-holes 1a and 1b, which are coupled by a coupling hole 1d between the through-holes 1a and 1b. The coupling degree of the coaxial through-hole is adjusted by the size, length, and position of the coaxial through-hole.

However, such a conventional dielectric filter has a narrow bandwidth, so that the size of the coupling holes has to be increased to secure the bandwidth used in mobile communication equipment, that is, about 20-30 MHz. It is difficult and the mechanical strength is also lowered. Particularly, the parts used in mobile communication devices such as automobiles and portable telephones are limited in size, and the size of the coupling cavity of the dielectric resonator is limited since the miniaturization and impact resistance are strictly required. There is a problem in securing a bandwidth of about MHz.

2A and 2B are a perspective view and a cross-sectional view of another conventional dielectric filter. Referring to FIGS. 2A and 2B, the dielectric filter of FIGS. 2A and 2B is the same as that of the dielectric filter shown in FIG. It adopts a structure in which all five surfaces except one surface and two inner surfaces of the through holes 2a and 2b are formed of conductor electrodes, and the coupling between the coaxial through holes built in the dielectric block 2 is different in dielectric cross-sectional shape. By giving 2b-1 (2b-2), the coupling is realized by the difference in characteristic impedance.

As described above, the method of realizing the coupling of the through-holes due to the cross-sectional shape of the inner conductor electrodes may be somewhat improved than the method of implementing the coupling between the conductive electrodes in the dielectric block as the coupling holes as shown in FIG. There are problems such as difficulty in obtaining the dielectric block into a uniform molded body.

3A and 3B are a perspective view and a cross-sectional view of another conventional dielectric filter, and the dielectric filter shown in FIGS. 3A and 3B, like the dielectric filter shown in FIGS. The through-holes 3a and 3b are formed, and a conductor electrode is formed on the surface. In this structure, the combination of the through-holes and the through-holes is a method of removing a part of the city electrode formed in the inner through-holes. Implement.

Such a method has advantages in that dielectric block formation is easy, but it is difficult to manufacture the surface electrode in the small dielectric block accurately.

The present invention has been made to solve the above problems.

Accordingly, an object of the present invention is to facilitate the adjustment of the coupling capacitance and the input / output capacitance in a dielectric block having a through hole formed to penetrate back and forth, while ensuring sufficient bandwidth and simplifying the structure. It is to provide an integrated dielectric filter having a simple structure that is easy to manufacture.

1 is a perspective view of a conventional dielectric filter.

2a and 2b are a perspective view and a cross-sectional view of another conventional dielectric filter.

3a and 3b are a perspective view and a sectional view of another conventional dielectric filter.

4 is a perspective view of a dielectric filter according to the present invention.

5 is an equivalent circuit diagram of FIG.

6 is a narrowband frequency characteristic diagram for the dielectric filter of the present invention.

7 is a broadband frequency characteristic diagram of the dielectric filter of the present invention.

* Explanation of symbols for main parts of the drawings

10: dielectric block 11a, 11b: through hole

12: external conductor electrode 13a, 13b: input / output conductor electrode

14a, 14b: internal conductor electrode 15a, 15b: conductor electrode

16, 17: opening part RE1, RE2: resonator

Cin, Cout: Input / Output Capacitor Cc: Coupling Capacitor

As a technical means for achieving the above object of the present invention, the filter of the present invention is a dielectric filter having a rectangular parallelepiped dielectric block and a plurality of through-holes formed through the front and rear surfaces of the dielectric block in the same shape. An external and internal conductor electrode having a front surface of the dielectric block as an open surface, and formed on all external surfaces except the open surface and the inner surface of the through hole; Input and output electrodes formed on a surface of the dielectric block on which the external conductor electrode is formed in an insulated state from the external conductor electrode; A conductive electrode having a predetermined pattern formed on an open surface of the dielectric block to be insulated from the outer conductor electrode and to be insulated from each other of the through holes and to be connected to the inner conductor electrodes of the through holes; Characterized in having a.

Hereinafter, with reference to the accompanying drawings, preferred embodiments of the integrated dielectric filter having a simple structure according to the present invention will be described in detail. In the drawings referred to in the present invention, components having substantially the same configuration and function will use the same reference numerals.

4 is a perspective view of a dielectric filter according to the present invention, and FIG. 5 is an equivalent circuit diagram of FIG. 4. 4 and 5, the dielectric filter according to the present invention includes a plurality of coaxial through-holes formed in the same direction through the dielectric block 10 of the rectangular parallelepiped and the front and rear surfaces of the dielectric block 10. 11a, 11b).

In addition, the front surface of the dielectric block 10 is opened to the dielectric block 10, and all external surfaces except for the open surface and external and internal conductor electrodes on the inner surfaces of the through holes 11a and 11b. (12, 14a, 14b) and input and output electrodes (13a, 13b) are formed on the surface of the dielectric block (10) on which the external conductor electrode (12) is formed, insulated from the external conductor electrode (12). Let's do it.

In addition, the dielectric block 10 is kept insulated from the external conductor electrode 12 of the dielectric block 10 and is also insulated from each other through the through holes 11a and 11b. Conductor electrodes 15a and 15b of a predetermined pattern are formed on an open surface so as to be connected to the inner conductor electrodes 14a and 14b of 11a and 11b. The conductor electrodes 15a and 15b and the external conductor electrode of the predetermined pattern are formed. An opening portion having a predetermined width L1 is formed between the portions 12 and an opening portion having a predetermined width L2 is formed between the conductive electrodes 15a and 15b of the predetermined pattern formed on the opening surface.

By adjusting the width of the predetermined width L1, it is possible to adjust the value of the coupling capacitor Cc between the resonators RE1 and RE2 shown in FIG. 5, and when the width of the predetermined width L2 is adjusted, FIG. The values of the input and output capacitors Cin and Cout shown are adjusted.

By adjusting the predetermined widths L1 and L2 made as described above, the coupling capacitance and the input / output capacitance can be adjusted, so that the filter characteristics can be improved as shown in FIGS. 6 and 7.

FIG. 6 is a narrowband frequency characteristic diagram of the dielectric filter of the present invention, and FIG. 7 is a spurious frequency characteristic diagram of the dielectric filter of the present invention.

Referring to the characteristics shown in FIG. 6, the bandwidth of the dielectric filter is about 20-30 MHz and the insertion loss in the pass band is about 1.65 dB, whereas the insertion loss in the stop band is about 20-25 dB. have. Therefore, the dielectric filter according to the present invention has an advantage of low insertion loss and excellent selection characteristics in the passband.

According to the present invention as described above, in the integrated dielectric block having a coaxial through-hole formed to penetrate back and forth inside, the coupling capacitance and the input / output capacitance can be easily adjusted, and at the same time, sufficient bandwidth can be secured. In addition, since the structure of the dielectric block can be simplified and easily manufactured, there is a unique effect that the mass productivity is formed.

The above description is only a description of one embodiment of the present invention, the present invention is capable of various changes and modifications within the scope of the configuration. In addition, one of ordinary skill in the art will readily recognize that the integrated dielectric filter is not limited to the above-described embodiment.

Claims (2)

A dielectric filter having a rectangular parallelepiped dielectric block 10 and a plurality of through holes 11a and 11b formed through the front and rear surfaces of the dielectric block 10 in the same direction, wherein the dielectric block 10 is provided. External and internal conductor electrodes 12, 14a, and 14b formed with all front surfaces of the through holes 11a and 11b except for the open surface and the front surface of the front surface being opened; Input and output electrodes (13a, 13b) formed on a surface of the dielectric block (10) on which the external conductor electrode (12) is formed in an insulated state from the external conductor electrode (12); While maintaining the insulating state with the outer conductor electrode 12 of the dielectric block 10, the insulating hole is also maintained between the through holes 11a and 11b, and the inner conductor electrode of the through holes 11a and 11b. Conductor electrodes 15a and 15b having a predetermined pattern formed on the open surface so as to be connected to 14a and 14b; An integrated dielectric filter having a simple structure, characterized in that it comprises a. The method of claim 1, wherein an opening having a predetermined width L1 is formed between the conductive electrodes 15a and 15b of the predetermined pattern formed on the open surface of the dielectric block 10 and the external conductor electrode 12. An integrated dielectric filter having a simple structure, characterized in that an opening having a predetermined width (L2) is formed between conductor electrodes (15a, 15b) of a predetermined pattern formed on the surface.

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