KR101216910B1 - Rf filter for tuning coupling amount or transmission zero - Google Patents

Abstract

An RF filter, such as an RF cavity filter, is disclosed that can adjust the amount of cross coupling or transmission zero. The RF filter includes a housing member, a cover coupled to an upper portion of the housing member, a first tuning region formed on one surface of the cover, a second tuning region formed on one surface of the cover while being separated from the first tuning region, and the tuning region. And a first tuning element formed between the dielectric region formed on one surface of the cover and the dielectric region. Here, the first tuning region and the second tuning region are conductive regions.

Description

RF filter with adjustable coupling amount or zero transmission {RF FILTER FOR TUNING COUPLING AMOUNT OR TRANSMISSION ZERO}

The present invention relates to an RF filter, for example an RF cavity filter, which can adjust the amount of cross coupling or transmission zero.

RF cavity filter forms a number of cavities inside the filter to use frequency band

As a device for passing only a signal of, it is used in a base station or the like where a relatively high power frequency signal is used.

1 is a plan view showing the internal configuration of a typical RF cavity filter.

Referring to FIG. 1, the RF cavity filter includes a plurality of cavities 110, 112, 114, 116 defined by an input connector 100, an output connector 102, a housing member 104, a housing member 104, and a partition wall. , 118, 120, a plurality of resonators 130, 132, 134, 136, 138, 140 and coupling bars 160 accommodated in each cavity.

An RF signal is applied to the input connector 100, and an RF signal applied to the input connector 100 is provided to the cavity 110. Each cavity 110, 112, 114, 116, 118, 120 and

The resonators 130, 132, 134, 136, 138, and 140 housed in each cavity are respectively LC resonant elimens

Works with.

The movement of signals from one cavity to another is via coupling window 150.

Is done.

The resonant frequency of the filter is determined by the size of the cavity and the size of the resonator. Although not shown in FIG. 1, the fine tuning operation is performed using a plurality of tuning bolts.

Can be done.

An important characteristic of the band pass characteristics of the filter is the skirt characteristic. The skirt characteristic means a slope in the boundary band in the band pass characteristic curve of the filter, and the skirt characteristic is preferably set steeply.

Such a skirt characteristic is improved as the order of the filter increases, that is, as the number of cavities and resonators increases, but the skirt characteristic has a trade-off relationship with another loss characteristic of the filter. . That is, as the number of cavities and resonators increases, the skirt characteristic of the filter is improved, but inversely, the insertion loss increases.

A method for improving skirt properties has been conventionally used by forming notches by cross coupling to improve skirt properties while maintaining a constant insertion loss.

Cross coupling is not sequential coupling between resonators through coupling window 150, but resonators that are not adjacent through a coupling window, such as coupling between second resonator 132 and fifth resonator 138. Means coupling between. Such cross coupling is typically accomplished using the coupling bar 160.

The coupling bar 160 penetrates the partition wall between the second cavity 122 and the fifth cavity 128 and is made of a metal material. The coupling bar 160 is operated such that, for example, a signal associated with the second resonator 132 is coupled to the fifth resonator 138, and such coupling operation is performed through the metal coupling bar 160. This can be done.

Holes are formed in the partition wall between the second cavity 122 and the fifth cavity 128 to penetrate the coupling bar 160, and a dielectric layer is formed on the inner circumferential surface of the hole so that the coupling bar 160 is electrically connected to the partition wall. Coupling should be made in a state where it is not coupled.

However, the cross coupling structure using the coupling bar 160 has a problem in that it is not possible to control the amount of coupling between the resonance periods that are cross coupled. The amount of cross coupling is determined by the size of the coupling bar 160. Conventionally, when the coupling required for cross coupling is not achieved, the coupling bar 160 should have been replaced with a coupling bar 160 having a different size. The coupling amount with the ring bar 160 mounted could not be adjusted.

Also, there was no way to adjust the transmission zero associated with the skirt characteristics.

The present invention provides an RF filter, in particular an RF cavity filter, which can adjust the amount of cross coupling or transmission zero.

In order to achieve the above object, the RF filter according to an embodiment of the present invention comprises a housing member; A cover coupled to an upper portion of the housing member; A first tuning region formed on one surface of the cover; A second tuning region formed on one surface of the cover while being separated from the first tuning region; A dielectric region formed between the tuning regions and formed on one surface of the cover; And a first tuning element arranged over the dielectric region. Here, the first tuning region and the second tuning region are conductive regions.

According to another embodiment of the present invention, an RF filter includes a housing member; A cover coupled to an upper portion of the housing member; A first tuning region formed on one surface of the cover; A second tuning region formed on one surface of the cover while being separated from the first tuning region; A dielectric region formed between the tuning regions and formed on one surface of the cover; A first tuning element received through the first tuning region of the cover and inside the housing member; A second tuning element received through the second tuning region of the cover and inside the housing member; And a tuning sliding member arranged on one surface of the cover. Here, a portion of the tuning sliding member overlaps with the dielectric region.

According to one or more exemplary embodiments, a cover covering a housing member including cavities includes: a first tuning region and a second tuning region located separately from each other; And a dielectric region formed between the tuning regions. Here, a first tuning element is received as a first cavity of the cavities through the first tuning region, a second tuning element is received as a second cavity of the cavities through the second tuning region, The tuning regions are conductive regions.

The RF filter according to the present invention adjusts the capacitance between the tuning elements by using a lumped element or a tuning sliding member in a state where the tuning elements are installed to be received into the corresponding cavities through the cover, so that the cross couple between the corresponding resonators Ring amount or transmission zero can be adjusted.

In particular, since the concentrating element and the tuning sliding member can be adjusted from the outside, tuning is easy.

1 is a plan view showing the internal configuration of a typical RF cavity filter.
2 is a perspective view illustrating an RF filter according to a first embodiment of the present invention.
3 is a diagram illustrating a structure of an RF filter according to an embodiment of the present invention.
4 is a top view showing a cover according to an embodiment of the present invention.
5 is a perspective view illustrating an RF filter according to a second embodiment of the present invention.
6 is a top view illustrating a cover portion of the RF filter of FIG. 5 according to an embodiment of the present invention.
7 is a view showing a cover portion of the RF filter according to the third embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 is a perspective view illustrating an RF filter according to a first embodiment of the present invention.

Referring to FIG. 2, the RF filter of the present embodiment is, for example, an RF cavity filter, and includes a housing member 200, a cover 202, an input connector 204, an output connector 206, and a plurality of cavities 208. , Resonators 210, barrier ribs 212, and a first tuning element 230.

The housing member 200 protects components such as the resonator 210 inside the filter and shields electromagnetic waves. The housing member 200 may be formed by, for example, plating silver having high conductivity on an aluminum material.

The cover 202 may be coupled to the upper portion of the housing member 200, and may be coupled to the upper portion of the housing member 200, for example, by bolting or the like. This cover 202 may also be formed by, for example, plating silver on an aluminum material, and serves as an electrical ground.

The input connector 204 is a passage through which an RF signal is input, and the RF signal input through the input connector 204 is output to the output connector 206, which is transmitted through a coupling window formed in each cavity 208. Proceed. In this case, a resonance phenomenon of the RF signal is generated by the cavities 208 and the resonators 210, and the RF signal is filtered by the resonance phenomenon.

The cavities 208 are defined by the partitions 212, and resonators 210 may be formed in the cavities 208, respectively. In this case, as the number of resonators 210 and cavities 208 increases, the skirt characteristics of the filter may be improved, but insertion loss may decrease. Is determined.

The resonator 210 may be a cylindrical resonator as shown in FIG. 2, but various types of resonators such as a disc type resonator may be used. The material of the resonator 210 may be a metal resonator or a dielectric resonator according to a mode (TE mode or TM mode) of the RF filter.

The first tuning element 230 is used to adjust the amount of cross coupling or transmission zero as metal, for example, and is located on the top surface of the cover 202.

According to an embodiment of the present invention, the first tuning element 230 may be a concentrated element such as a capacitor, an inductor, or the like.

Hereinafter, a process of adjusting the coupling amount or the transmission zero using the first tuning element 230 and the structure of the RF filter will be described with reference to the accompanying drawings.

3 is a view showing the structure of an RF filter according to an embodiment of the present invention, Figure 4 is a top view showing a cover according to an embodiment of the present invention.

Referring to FIG. 4A, an etching region 400a, a first tuning region 402a, a second tuning region 402b, and a dielectric region 410 are formed on the top surface 202a of the cover 202.

Referring to FIG. 4B, etching regions 400b and 400c, a third tuning region 406, and a fourth tuning region 408 are formed on the bottom surface 202b of the cover 202.

Tuning regions 402a, 402b, 406 and 408 are conductive regions, for example plated with a conductive material.

First holes 404a are formed in the first tuning region 402a and the third tuning region 406, and second holes 404b are formed in the second tuning region 402b and the fourth tuning region 408. do. In this case, as shown in FIG. 3, for example, a second tuning element 214a, which is a conductor, penetrates through the first tuning region 402a and the third tuning region 406 of the cover 202 to allow the first cavity ( 208a, a third tuning element 214b, for example, a conductor, penetrates through the second tuning region 402b and the fourth tuning region 408 of the cover 202 to the second cavity 208b. do.

According to one embodiment of the present invention, threads are formed on the outer circumferential surfaces of the second tuning element 214a and the third tuning element 214b, so that the second tuning element 214a or the third tuning element 214b is Rotating allows the second tuning element 214a or the third tuning element 214b to move up and down while being supported by the cover 202.

The second tuning element 214a is fixed to the top surface 202a of the cover 202 by the first nut 216a, and the third tuning element 214b is fixed to the cover 202 by the second nut 216b. It may be fixed to the upper surface 202a.

The dielectric region 410 is located between the first tuning region 402a and the second tuning region 402b inside the first etching region 400a. Here, the first tuning region 400a and the second tuning region 400b are physically separated, but coupling occurs due to the dielectric region 410. In other words, a predetermined capacitance is formed between the first tuning region 402a and the second tuning region 402b. Thus, the second tuning element 214a and the third tuning element 214b are electrically connected via a coupling scheme, so that the resonators in the cavities 208a and 208b in which the tuning elements 214a and 214b are accommodated. Cross coupling occurs between 210a and 210b.

According to one embodiment of the invention, a first tuning element 230, which is a concentrating element, is arranged over the dielectric region 410. As a result, the capacitance between the first tuning region 402a and the second tuning region 402b is changed due to the first tuning element 230, for example a capacitor, and as a result, between the resonators 210a and 210b The amount of cross coupling or transmission zero is variable. That is, the cross coupling amount or transmission zero between the resonators 210a and 210b may vary depending on the first tuning element 230 arranged on the dielectric region 410 as shown in FIG. 4C. Thus, if one wishes to adjust the desired cross coupling amount or transmission zero, an appropriate first tuning element 230 is selected and arranged over the dielectric region 410.

According to an embodiment of the present invention, the user may adjust the coupling amount or the transmission zero by changing only the first tuning element 230 with the second tuning element 214a and the third tuning element 214b fixed. In addition, the coupling amount or the transmission zero may be adjusted using the second tuning element 214a or the third tuning element 214b as well as the first tuning element 230. Of course, the second tuning element 214a or the third tuning element 214b moves up and down.

According to another embodiment of the present invention, the groove 220 may be formed on the upper surface of the partition wall 212. This is to prevent the conductive material of the tuning regions 406 and 408 formed on the back 202b of the cover 202 from being electrically connected to the partition 212.

In terms of process, etching the top and back surfaces of the cover 202 formed by plating a conductive material over the dielectric material in accordance with the tuning regions 402a, 402b, 406 and 408 results in etching regions 400a, 400b and 400c. The conductive material is formed in the etching regions 400a, 400b, and 400c. As a result, the tuning regions 402a, 402b, 406 and 408 are electrically separated from the conductive material of the cover 202 by the etching regions 400a, 400b and 400c. Thus, the second and third tuning elements 214a and 214b are not connected to the conductive material of the cover 202, ie not to ground.

Meanwhile, the dielectric region 410 may be formed by removing the plating material of the cover 202, that is, the top surface of the dielectric material constituting the cover 202 is exposed to the outside.

In summary, the RF filter of the present embodiment may adjust the amount of cross coupling or transmission zero using the first tuning element 230.

5 is a perspective view illustrating an RF filter according to a second embodiment of the present invention, and FIG. 6 is a top view illustrating a cover portion of the RF filter of FIG. 5 according to an embodiment of the present invention.

Referring to FIG. 5, the RF filter of the present embodiment includes a housing member 200, a cover 202, a first tuning element 214a, a second tuning element 214b, a first nut 216a, and a second nut ( 216b) and a tuning sliding member 500 that is a dielectric.

Referring to FIG. 6A, an etching region 600a, a first tuning region 602a, a second tuning region 602b, and a dielectric region 502 are formed on the top surface 202a of the cover 202.

Referring to FIG. 6B, etching regions 600b and 600c, a third tuning region 606, and a fourth tuning region 608 are formed on the bottom surface 202b of the cover 202.

Tuning regions 602a, 602b, 606 and 608 are conductive regions, for example plated with a conductive material.

The first tuning element 214a is received into the first cavity 208a through the first tuning region 602a and the third tuning region 606 of the cover 202, and the second tuning element 214b is covered. A second cavity 208b is received through the second tuning region 602b and the fourth tuning region 608 of 202.

The first tuning element 214a is fixed to the top surface 202a of the cover 202 by the first nut 216a, and the second tuning element 214b is fixed to the cover 202 by the second nut 216b. It may be fixed to the upper surface 202a.

The dielectric region 502 is located between the first tuning region 602a and the second tuning region 602b inside the first etching region 600a. Here, the first tuning region 600a and the second tuning region 600b are physically separated, but coupling occurs.

According to an embodiment of the present invention, two holes 610 and 612 may be formed in the tuning sliding member 500 as shown in FIG. 6D. The tuning sliding member 500 of this structure is fixed to the first tuning element 214a or the first nut 216a which is received as the first cavity 208a through the cover 202 through the first hole 610. As shown in FIG. 6C, the first tuning element 214a or the first nut 216a may be fixed. In this case, the termination portion of the tuning sliding member 500 overlaps the dielectric region 502, and the capacitance between the tuning elements 602a and 602b varies according to the overlap area, so that the cross coupling between the corresponding resonators is performed. The amount or transmission zero can vary. On the other hand, the tuning sliding member 500 may move in the front-rear direction. Of course, after the tuning sliding member 500 is moved to a desired position, the tuning sliding member 500 may be fixed through various methods.

In summary, the RF filter of the present embodiment adjusts the overlap area of the tuning sliding member 500 and the dielectric region 502 arranged on the top surface 202a of the cover 202 to transfer or reduce the amount of cross coupling between the corresponding resonators. You can adjust the zero.

While the tuning sliding member 500 is shown in the rectangle above, various shapes as long as the tuning sliding member 500 can overlap the dielectric region 502 to vary the capacitance between the tuning elements 602a and 602b. It can be transformed into.

In addition, although the tuning sliding member 500 is arranged at a position corresponding to the first tuning element 214a in FIG. 6, it may be arranged at a position corresponding to the second tuning element 214b.

Although not mentioned above, the tuning elements 602a and 602b may rotate and move up and down.

7 is a view showing a cover portion of the RF filter according to the third embodiment of the present invention.

Referring to FIG. 7, the tuning sliding member 700 is arranged on the upper surface 202a of the cover 202 of the RF filter of this embodiment. However, unlike in the second embodiment in which the tuning sliding member 500 was supported by the first tuning element 214a, the tuning sliding member 700 is the first tuning element 214a as shown in Fig. 7C. ) Are arranged up. Of course, a portion of the tuning sliding member 700 overlaps the dielectric region 702 to vary the amount of cross coupling between the resonators or the transmission zero.

A hole 710 may be formed in the tuning sliding member 700 as illustrated in FIG. 7D.

The embodiments of the present invention described above are disclosed for purposes of illustration, and those skilled in the art having ordinary knowledge of the present invention may make various modifications, changes, and additions within the spirit and scope of the present invention. Should be considered to be within the scope of the following claims.

00: input connector 102: output connector
104: housing member 110, 112, 114, 116, 118, 120: cavity
130, 132, 134, 136, 138, 140: resonator 150: coupling window
160: coupling bar 200: housing member
202: cover 204: input connector
206: output connector 208: cavity
210: resonator 212: partition wall
214 tuning element 216 nut
230: tuning element 400: etching area
402a: first tuning region 402b: second tuning region
404: hole 406: third tuning region
408: fourth tuning region 410: dielectric region
500: tuning sliding member 502: dielectric region
600: etching region 602a: first tuning region
602b: second tuning region 604: hole
606: third tuning region 608: fourth tuning region
700: tuning sliding member 702: dielectric region

Claims (13)

A housing member;
A cover coupled to an upper portion of the housing member;
A first tuning region formed on one surface of the cover;
A second tuning region formed on one surface of the cover while being separated from the first tuning region;
A dielectric region formed between the tuning regions and formed on one surface of the cover; And
A first tuning element arranged over said dielectric region,
And the first tuning region and the second tuning region are conductive regions. The method of claim 1, wherein the RF filter,
Cavities defined by partitions in the housing member;
Resonators housed in the cavities;
A third tuning region formed on the rear surface of the cover;
A fourth tuning region formed on a rear surface of the cover while being separated from the third tuning region;
A second tuning element received through the first tuning region and the third tuning region of the cover as a first cavity of the cavities; And
A third tuning element penetrating through the second tuning region and the fourth tuning region of the cover and received as a second one of the cavities,
The cover is formed by plating a conductive material over a dielectric member, the first tuning element is a lumped element, and a portion of an upper surface of the cover is etched to replace the first tuning region and the second tuning region. And a portion of the back side of the cover is etched to form the third tuning region and the fourth tuning region, the cross coupling amount or transmission zero between the corresponding resonators in accordance with the first tuning element. RF filter, characterized in that different. 3. The second tuning element and the third tuning element are each bolts, the second tuning element is fixed to the top surface of the cover by a first nut, and the third tuning element is second nut. It is fixed to the upper surface of the cover by
The second tuning element and the third tuning element are arranged symmetrically with respect to a specific partition wall, a groove is formed in the upper surface of the partition wall, the second tuning element and the third tuning element is movable up and down. Featuring an RF filter. A housing member;
A cover coupled to an upper portion of the housing member;
A first tuning region formed on one surface of the cover;
A second tuning region formed on one surface of the cover while being separated from the first tuning region;
A dielectric region formed between the tuning regions and formed on one surface of the cover;
A first tuning element received through the first tuning region of the cover and inside the housing member;
A second tuning element received through the second tuning region of the cover and inside the housing member; And
Including a tuning sliding member arranged on one surface of the cover,
A portion of the tuning sliding member overlaps the dielectric region. The method of claim 4, wherein the RF filter,
Cavities defined by partitions in the housing member; And
Further comprising resonators housed in the cavities,
A first hole and a second hole are formed in a portion of the tuning sliding member, and the tuning sliding member is slidable while being supported by the first tuning element through the first hole, and the tuning sliding member and the dielectric RF filter, characterized in that the amount of cross coupling between the resonators or the transmission zero varies according to the overlap area of the region. The method of claim 4, wherein the RF filter,
Cavities defined by partitions in the housing member; And
Further comprising resonators housed in the cavities,
The tuning sliding member is slidable in a state arranged on the first tuning element, and the cross coupling amount or the transmission zero between the corresponding resonators varies according to the overlap area of the tuning sliding member and the dielectric region. RF filter. 5. The method of claim 4, wherein the cover is formed by plating a conductive material over a dielectric member, a portion of the top surface of the cover is etched to form the first tuning region and the second tuning region, wherein the tuning sliding member is An RF filter comprising a dielectric material. 5. The method of claim 4, wherein at least one of the tuning elements is movable up and down, wherein the first tuning element and the second tuning element are each bolts, and the first tuning element is a top surface of the cover by a first nut. Fixed to the upper surface of the cover by a second nut,
And the second tuning element and the third tuning element are symmetrically arranged with respect to a specific partition wall, and a groove is formed in an upper surface of the partition wall. A cover for covering a housing member including cavities,
A first tuning region and a second tuning region located separately from each other; And
A dielectric region formed between the tuning regions,
A first tuning element is received through the first tuning region as a first one of the cavities, a second tuning element is received through the second tuning region as a second one of the cavities, and the tuning A cover used in an RF filter, wherein the regions are conductive regions. The method of claim 9, wherein the third tuning region and the fourth tuning region separated from each other are formed on the rear surface of the cover,
The first tuning element is accommodated in the first cavity through the first tuning region and the third tuning region, and the second tuning element passes through the second tuning region and the fourth tuning region to allow the second tuning element to pass through the second tuning region. A cover for use in an RF filter, which is housed in a cavity. The method of claim 10, wherein the cover is formed by plating a conductive material over a dielectric material, and the first tuning region and the second tuning region are formed by etching the top surface of the cover, and the back surface of the cover is etched. Thereby forming the third tuning region and the fourth tuning region, wherein all of the tuning regions are not electrically connected to the conductive material of the cover. 10. The system of claim 9, wherein a tuning sliding member is arranged on the cover,
The tuning sliding member is slidable on the cover, the portion of the tuning sliding member and the dielectric region overlap, the cross coupling amount or transmission zero between the resonators vary depending on the overlap area Cover used for the filter. 10. A cover as claimed in claim 9, wherein a concentrating element is arranged above the dielectric region and the amount of cross coupling between the resonators or the transmission zero varies depending on the concentrating element.

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