KR102334045B1 - Waveguide resonator filter made with multiple substrates - Google Patents

Abstract

A resonator filter is disclosed. The resonator filter includes a first substrate having a quadrangular plate-like structure and disposed under the first substrate, and having first, second, third, and fourth holes having a quadrangular structure, and first to fourth holes a second substrate including first through-vias disposed so as to completely surround the substrates and second through-vias disposed on barrier ribs separating the first to fourth holes; a second substrate disposed under the second substrate and disposed under the second substrate; A third substrate including a first region and a second region for input/output ports, wherein the third substrate includes a fifth hole and a sixth hole formed at positions corresponding to the first to fourth holes of the second substrate, respectively , a seventh hole, and an eighth hole, and a first circular patch, a second circular patch, a third circular patch, and a fourth circular patch disposed in each of the fifth to eighth holes, and the second and third An upper conductive thin film including a conductive strip for inducing coupling of a first polarity to circular patches, first to fourth conductive pillars disposed under the upper conductive thin film and electrically connected to the first to fourth circular patches; An insulator including first through-vias disposed along a portion of an edge of the first region, second through-vias disposed at a portion of a position corresponding to a partition wall, and third through-vias constituting input/output ports in the second region , and a lower conductive thin film disposed under the insulator and having a rectangular plate-like structure, a portion of which is removed to constitute an input/output port.

Description

WAVEGUIDE RESONATOR FILTER MADE WITH MULTIPLE SUBSTRATES

The present invention relates to a resonator filter, and more particularly, to a bandpass cavity resonator filter having a multilayer substrate structure.

In general, in a wireless communication system and radar, communication and detection functions are performed using a frequency filtered by a bandpass filter. In general, a waveguide-type bandpass filter has a smaller insertion loss than a planar structure filter and has high power handling performance. In addition, when designing a filter using a dual-mode waveguide resonator, the size of the filter can be reduced by two times compared to when designing a filter using a single-mode resonator. Another method of reducing the size of the filter is to design a filter using a waveguide resonator with a post inserted in the center.

Because the high-performance bandpass waveguide filter has a three-dimensional non-planar structure, it is generally manufactured by processing it using a solid such as aluminum, then silver plating, and then assembling it. Therefore, a detailed manufacturing process of several steps is essential, and there is a disadvantage that the manufacturing period is long. In particular, for example, when there is a structure such as a post inside the resonator constituting the filter and when there is an ancillary structure for realizing negative coupling, the number of manufacturing steps increases and the manufacturing period is long because it is not easy to manufacture. There is a downside to losing. Another disadvantage is that since the input/output ports are generally formed as coaxial connectors, they are not compatible with general printed circuit boards (PCBs).

S. Nam, B. Lee, B. Koh, C. Kwak, and J. Lee, “K-band fully reconfigurable pseudo-elliptic waveguide resonator filter with tunable positive and negative couplings,” IEICE Transactions on Communications, vol. 99, pp. 2136-2145, Oct, 2016.

The problem to be solved by the present invention is to provide a resonator filter that is easy to manufacture and compatible with a printed circuit board.

In order to achieve the object to be solved, the resonator filter according to the embodiments of the present invention includes a first substrate having a rectangular plate-like structure, disposed under the first substrate, and a first hole, a second hole, and a third having a rectangular structure. a fourth hole having a hole and a fourth hole and including first through-vias disposed to entirely surround the first to fourth holes and second through-vias disposed on a partition wall separating the first to fourth holes a second substrate, and a third substrate disposed under the second substrate and including a first region on which the second substrate is disposed and a second region for input/output ports, wherein the third substrate comprises: the second substrate A first circular patch having a fifth hole, a sixth hole, a seventh hole, and an eighth hole formed at positions corresponding to the first to fourth holes, respectively, and disposed in each of the fifth hole to the eighth hole , an upper conductive thin film comprising a second circular patch, a third circular patch, and a fourth circular patch, and a conductive strip for inducing coupling of a first polarity to the second and third circular patches; first to fourth conductor pillars disposed on the ridge and electrically connected to the first to fourth circular patches, first through vias disposed along a portion of an edge of the first region, and a position corresponding to the partition wall an insulator including second through-vias disposed in a portion of the second region, third through-vias constituting the input/output ports in the second region, and a portion disposed under the insulator and having a rectangular plate-like structure to constitute the input/output ports includes a lower conductive thin film from which is removed.

According to embodiments of the present invention, by forming the conductor strips for forming the coupling structure of different polarity together when forming the circular patch of the post, it is easier to manufacture the resonator filter. In addition, since the input/output ports have a grounded co-planar waveguide (GCPW) structure, the resonator filter is compatible with the printed circuit board.

In order to more fully understand the drawings recited in the Detailed Description, a detailed description of each drawing is provided.
1 is an exploded perspective view for explaining a resonator filter according to an embodiment of the present invention.
FIG. 2 is a perspective view illustrating a structure of a third substrate in the resonator filter shown in FIG. 1 .
FIG. 3 is a top view of the third substrate shown in FIG. 2 .
FIG. 4 is a bottom view of the third substrate shown in FIG. 2 .
FIG. 5 is a graph showing the resonator filter coupling diagram shown in FIG. 1 .
6 is a graph showing a simulation result of a resonator filter according to an embodiment of the present invention.
7 is a graph illustrating a measurement result of a resonator filter according to an embodiment of the present invention.

Specific structural or functional descriptions of the embodiments according to the concept of the present invention disclosed in this specification are only exemplified for the purpose of explaining the embodiments according to the concept of the present invention, and the embodiments according to the concept of the present invention are It may be implemented in various forms and is not limited to the embodiments described herein.

Since the embodiments according to the concept of the present invention may have various changes and may have various forms, the embodiments will be illustrated in the drawings and described in detail herein. However, this is not intended to limit the embodiments according to the concept of the present invention to specific disclosed forms, and includes all modifications, equivalents, or substitutes included in the spirit and scope of the present invention.

Terms such as first or second may be used to describe various elements, but the elements should not be limited by the terms. The above terms are used only for the purpose of distinguishing one component from another, for example without departing from the scope of the inventive concept, a first component may be termed a second component and similarly a second component A component may also be referred to as a first component.

When a component is referred to as being “connected” or “connected” to another component, it is understood that it may be directly connected or connected to the other component, but other components may exist in between. it should be On the other hand, when it is said that a certain element is "directly connected" or "directly connected" to another element, it should be understood that the other element does not exist in the middle. Other expressions describing the relationship between components, such as "between" and "immediately between" or "neighboring to" and "directly adjacent to", etc., should be interpreted similarly.

The terms used herein are used only to describe specific embodiments, and are not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly dictates otherwise. In this specification, terms such as "comprise" or "have" are intended to designate that a feature, number, step, operation, component, part, or combination thereof described herein exists, but one or more other features It should be understood that it does not preclude the possibility of the presence or addition of numbers, steps, operations, components, parts, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and should not be interpreted in an ideal or excessively formal meaning unless explicitly defined in the present specification. does not

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the scope of the patent application is not limited or limited by these examples. Like reference numerals in each figure indicate like elements.

Hereinafter, a waveguide-type bandpass resonator filter will be described. Since the bandpass filter has a waveguide shape, an insertion loss is smaller than that of a planar structure filter and has high power handling performance. In addition, when the filter is designed using the dual-mode waveguide resonator, the size of the filter can be reduced to 1/2 or less than when the filter is designed using the single-mode waveguide resonator. In addition, if a waveguide resonator having a post inserted in the center is used, the size of the filter can be further reduced.

1 is an exploded perspective view for explaining a resonator filter according to an embodiment of the present invention, FIG. 2 is a perspective view for explaining the structure of a third substrate in the resonator filter shown in FIG. 1 , and FIG. It is a top view of the illustrated third substrate, and FIG. 4 is a bottom view of the third substrate illustrated in FIG. 2 .

1 to 4 , the resonator filter 1000 may include a plurality of vertically stacked substrates. According to an embodiment, the resonator filter 1000 may include a first substrate 100 , a second substrate 200 , and a third substrate 300 .

The first substrate 100 is disposed on the top of the resonator filter 1000 and may have a rectangular plate-shaped structure. A commonly used conductor plate may be used as the first substrate 100 . According to an embodiment, the first substrate 100 may be implemented using one surface of a general substrate as a conductor surface. For example, the first substrate 100 may include FR4 epoxy.

The second substrate 200 is disposed under the first substrate 100 and may have the same size and shape as the first substrate 100 . In addition, the second substrate 200 may include the same FR4 epoxy as the first substrate 100 . For example, the thickness of the second substrate 200 may be 0.2 mm.

According to an embodiment of the present invention, the second substrate 200 may include a plurality of holes for forming an air layer. In this embodiment, the bandpass cavity resonator filter 1000 will be described, but the filter 1000 including four resonators and having a coupling structure having one polarity different will be described as an example. However, in the resonator filter 1000 of the present invention, the number of resonators and the number of coupling structures having different polarities are not limited thereto.

According to an embodiment, the second substrate 200 includes four holes, and each of the four holes may have a rectangular structure in a plan view. In addition, the four holes may have the same size and be spaced apart from each other. For example, when the second substrate 200 has a quadrangular structure, the four holes may be disposed inside the second substrate 200 to have a predetermined spacing therebetween. Hereinafter, for ease of description, each of the four holes will be referred to as a first hole HL1 , a second hole HL2 , a third hole HL3 , and a fourth hole HL4 .

The first hole HL1 , the second hole HL2 , the third hole HL3 , and the fourth hole HL4 of the second substrate 200 may be divided by a barrier rib. According to an embodiment, a portion of the partition wall dividing the second hole HL2 and the third hole HL3 may be removed so that the second hole HL2 and the third hole HL3 communicate with each other. .

In the second substrate 200 , first through-vias TV1 are disposed to completely surround the first hole HL1 , the second hole HL2 , the third hole HL3 , and the fourth hole HL4 . and second through-vias TV2 formed in the partition wall may be provided. Each of the first through-vias TV1 and the second through-vias TV2 penetrates the second substrate 200 , and passes through the second substrate 200 to the first substrate 100 and the third substrate ( 300) may be electrically connected to each other. The first through-vias TV1 are spaced apart from each other by a first separation distance, and the gaps therebetween are narrow, which will be described below as being continuously disposed. The second through-vias TV2 may be continuously disposed, and may be disposed to be spaced apart from each other by a second separation distance greater than the first separation distance from the partition wall separating the second hole HL2 and the third hole HL3 . A passage PT may be formed in the partition wall separating the second hole HL2 and the third hole HL3 by the second through vias TV2 spaced apart from each other.

The via or via hole described herein is a hole having a cylindrical structure and may be formed by plating an inner surface of the hole with a conductive material. The conductive material may include copper, brass, silver, gold, and the like, but it is obvious that the scope of the present invention is not limited to the type of the conductive material.

The third substrate 300 may have a larger size than the second substrate 200 . According to an embodiment, the third substrate 300 may include a first area AR1 for resonators and a second area AR2 for input/output ports P_In and P_Out. For example, the second substrate 200 may be disposed to cover the first area AR1 of the third substrate 300 .

The third substrate 300 may include an upper conductive thin film 310 , an insulator 320 , and a lower conductive thin film 330 .

Four holes are formed in the upper conductive thin film 310 , and each of the four holes may be formed at positions corresponding to the four holes of the second substrate 200 to have the same size and shape. In addition, the upper conductive thin film 310 may have a barrier rib at a position corresponding to the barrier rib of the second substrate 200 having the same size and shape. For ease of description, each of the four holes of the upper conductive thin film 310 is referred to as a fifth hole HL5 , a sixth hole HL6 , a seventh hole HL7 , and an eighth hole HL8 . As in the second substrate 200 , in the upper conductive thin film 310 , a portion of the barrier rib between the sixth hole HL6 and the seventh hole HL7 is removed, so that the sixth hole HL6 and the seventh hole HL7 are removed. These can communicate with each other. Accordingly, a passage PT may be formed in portions of the barrier ribs of the sixth hole HL6 and the seventh hole HL7 among the barrier ribs of the upper conductive thin film 310 .

The upper conductive thin film 310 may include circular patches and a conductor strip (CS). The circular patches include a first circular patch CP1 and a second circular patch disposed at the centers of each of the fifth hole HL5, the sixth hole HL6, the seventh hole HL7, and the eighth hole HL8. CP2), a third circular patch CP3, and a fourth circular patch CP4 may be included. The conductive strip CS includes a first portion having a curvature to surround a portion of the second circular patch CP2 , and a second portion extending from the first portion and crossing the sixth hole HL6 and the seventh hole HL7 . It may include a portion and a third portion extending from the second portion and having a curvature to surround a portion of the third circular patch CP3. As an example, the conductor strip CS may have an “S” shape in a plan view.

According to an exemplary embodiment, in the upper conductive thin film 310 , the conductive strips CS are formed together while forming the circular patches, thereby facilitating the fabrication of the resonator filter 1000 .

The insulator 320 may include a thermoset microwave material (TMM).

The insulator 320 includes conductive posts electrically connected to the first to fourth circular patches CP1 , CP2 , CP3 , and CP4 , and a third portion disposed along an edge of the first region AR1 . The through-vias TV3, the fourth through-vias TV4 disposed at positions corresponding to the barrier rib of the upper conductive thin film 310 in the first area AR1, and the input/output port P_Out in the second area AR2 ) may include fifth through-vias TV5 constituting the . In this case, each of the conductor pillars, the third through-vias TV3 , the fourth through-vias TV4 , and the fifth through-vias TV5 penetrates the insulator 320 to form the upper conductive thin film 310 and the lower portion. The conductive thin films 330 may be electrically connected.

Conductive pillars are disposed along the edge of the first circular patch (CP1) at a position corresponding to the first circular patch (CP1), a plurality of first conductor pillars (P1) having a ring structure in a plan view; 2 at a position corresponding to the circular patch CP2, disposed along the edge of the second circular patch CP2 and having a ring structure in a plan view of a plurality of second conductor pillars P2 and the third circular patch CP3 A plurality of third conductor pillars P3 disposed along the edge of the third circular patch CP3 at corresponding positions and having a ring structure in a plan view, and a fourth at positions corresponding to the fourth circular patch CP4 It may include a plurality of fourth conductor pillars P4 disposed along the edge of the circular patch CP4 and having a ring structure in a plan view.

Accordingly, a first post including the first circular patch CP1 and the first conductor pillars P1 and a second post including the second circular patch CP2 and the second conductor pillars P2; A third post including the third circular patch CP3 and the third conductive pillars P3 and a fourth post including the fourth circular patch CP4 and the fourth conductive pillars P4 may be configured. have. Although the present embodiment describes the filter 1000 having posts in each cavity resonator, the present invention is also applicable to the filter 1000 without posts.

The first region AR1 of the insulator 320 has a first portion PAT1 corresponding to the fifth hole HL5 and a second portion PAT2 corresponding to the sixth hole HL6 in the upper conductive thin film 310 . , a third portion PAT3 corresponding to the seventh hole HL7 , and a fourth portion PAT4 corresponding to the eighth hole HL8 .

The third through-vias TV3 connect the first portion PAT1 , the second portion PAT2 , the third portion PAT3 , and the fourth portion PAT4 of the first area AR1 of the insulator 320 . The third through-vias TV3 are spaced apart from the first portion PAT1 to form a first passage and are spaced apart from the fourth portion PAT4 again to surround the first area AR1. A second passage may be formed. The first passage and the second passage are for the input/output ports (P_In, P_Out), and for ease of explanation, it will be described that the first passage is configured as the input port (P_In) and the second passage is configured as the output port (P_Out). . The opposite is also possible.

The fourth through-vias TV4 are spaced apart from each other to define a third passage in a partition wall that separates the first portion PAT1 and the second portion PAT2 , and the second portion PAT2 and the third portion PAT3 are spaced apart from each other. ) is spaced apart to define a fourth passage on the partition wall that separates it, is spaced apart to define a fifth passage on the partition wall that separates the third part (PAT3) and the fourth part (PAT4), and the fourth part ( The partition wall separating the PAT4 and the first portion PAT1 may be spaced apart from each other to define a sixth passage. In this case, the aforementioned conductive strip CS may be disposed in the fifth passage.

The fifth through-vias TV5 may be disposed in the second area AR2 and may extend from the third through-vias TV3 . According to an embodiment, the input port P_In is formed by the third through-vias TV3 extending from both ends of the first passage defined by the third through-vias TV3 to the end of the insulator 320 . can be Also, the output port P_Out may be formed by the third through-vias TV3 extending from both ends of the second passage defined by the third through-vias TV3 to the end of the insulator 320 .

The lower conductive thin film 330 has a rectangular plate-shaped structure, and a portion thereof may be removed from the end of the first region AR1 to correspond to the input port P_In and the output port P_Out of the insulator 320 . The lower conductive thin film 330 is disposed immediately adjacent to the third through-vias TV3 constituting the input port P_In, is parallel to each other, and crosses from the first area AR1 to the second area AR2. The first removal portion RMP1 surrounding a portion of the first conductor pillars P1 and the third through-vias TV3 constituting the output port P_Out are disposed immediately adjacent to each other, are parallel to each other, and are parallel to the first area AR1 ) may have a second removal portion RMP2 that crosses to the second area AR2 and surrounds a portion of the second conductor pillars P2 . Such a structure is called a grounded co-planar waveguide (GCPW).

In this way, since the resonator filter 1000 configures the input/output ports of the GCPW structure, the resonator filter 1000 can be mounted on a printed circuit board and used, so that it can have compatibility with the printed circuit board. In addition, when a connector such as a coaxial connector is used, since measurement using a measuring instrument or connection with another circuit to which the connector is attached can be used, usability can be further increased. That is, according to the present invention, it is possible to provide a filter structure of a waveguide resonator that is compatible with a printed circuit board (PCB) and can also be connected to a connector.

The resonator filter 1000 according to an embodiment of the present invention includes a first conductive pillar P1 , a first circular patch CP1 , and a first hole HL1 of a second substrate 200 . The resonator, the second resonator including the second conductor pillars P2 , the second circular patch CP2 , and the second hole HL2 of the second substrate 200 , and the third conductor pillars P3 . , a third resonator including the third circular patch CP3 , and the third hole HL3 of the second substrate 200 , the fourth conductor pillars P4 , the fourth circular patch CP4 , and the second substrate 200 . 2 It may include a fourth resonator including the fourth hole HL4 of the substrate 200 .

FIG. 5 is a graph showing the resonator filter coupling diagram shown in FIG. 1 .

In Fig. 5, the input port and the output port are denoted by "S" and "L", respectively, and numbers indicate resonators. That is, “1” denotes a first resonator, “2” denotes a second resonator, “3” denotes a third resonator, and “4” denotes a fourth resonator.

1 and 5 , the conductor strip CS may be disposed between the second resonator and the third resonator to form a coupling structure having a polarity different from that of the other resonators. For example, when a negative coupling structure is formed in the conductor strip CS, a negative coupling is formed between the second resonator and the third resonator, and the remaining resonators, that is, the first and second resonators, the third and the third resonator, are formed. A positive coupling structure may be formed between the four resonators and the first and fourth resonators, respectively. That is, a solid line indicates a positive bond and a dotted line indicates a negative bond. The opposite is also possible.

6 is a graph showing a simulation result of a resonator filter according to an embodiment of the present invention.

6 shows a case where the center frequency is 5 GHz and the bandwidth is 300 MHz in the resonator filter according to an embodiment of the present invention. It can be seen that a pair of transfer zero points are formed due to the negative coupling structure formed between the second and third resonators.

7 is a graph illustrating a measurement result of a resonator filter according to an embodiment of the present invention.

Referring to FIG. 7 , it can be confirmed that the simulation results are similar to those of FIG. 6 . That is, it can be confirmed that a pair of transfer zero points are formed even in the actual measurement result due to the negative coupling structure formed between the second and third resonators.

As mentioned above, although embodiments of the present invention have been described with reference to the accompanying drawings, those of ordinary skill in the art to which the present invention pertains can implement the present invention in other specific forms without changing its technical spirit or essential features. You can understand that there is Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive.

Although the present invention has been described with reference to the embodiment shown in the drawings, which is merely exemplary, those skilled in the art will understand that various modifications and equivalent other embodiments are possible therefrom. For example, the described techniques are performed in an order different from the described method, and/or the described components of the system, structure, apparatus, circuit, etc. are combined or combined in a different form than the described method, or other components Or substituted or substituted by equivalents may achieve an appropriate result. Accordingly, the true technical protection scope of the present invention should be determined by the technical spirit of the appended claims.

1000: resonator filter
100: first substrate
200: second substrate
300: third substrate
310: lower conductive thin film
320: insulator
330: upper conductive thin film
RMP1, RMP2: Removed part
CS: conductor strip

Claims (6)

a first substrate having a rectangular plate-like structure;
First through-vias disposed under the first substrate, having a first hole, a second hole, a third hole, and a fourth hole having a rectangular structure, and disposed to entirely surround the first to fourth holes and a second substrate including second through-vias disposed on barrier ribs separating the first to fourth holes; and
a third substrate disposed under the second substrate and including a first region on which the second substrate is disposed and a second region for input/output ports;
The third substrate is
It has a fifth hole, a sixth hole, a seventh hole, and an eighth hole formed at positions corresponding to the first to fourth holes of the second substrate, and is disposed in each of the fifth to eighth holes. an upper conductive thin film comprising a first circular patch, a second circular patch, a third circular patch, and a fourth circular patch, and a conductive strip for inducing coupling of a first polarity to the second and third circular patches;
first to fourth conductive pillars disposed under the upper conductive thin film and electrically connected to the first to fourth circular patches, first through vias disposed along a portion of an edge of the first region, and the an insulator including second through-vias disposed at a portion of a position corresponding to the partition wall and third through-vias constituting the input/output ports in the second region; and
and a lower conductive thin film disposed under the insulator, having a rectangular plate-like structure, and having a portion removed to form the input/output port.
According to claim 1,
a coupling structure of a first polarity is defined between the second and third circular patches in the conductor strip;
A resonator filter in which a coupling structure having a second polarity opposite to the first polarity is defined between the first and second circular patches, the third and fourth circular patches, and the first and fourth circular patches .
According to claim 1,
a first resonator including the first hole, the first circular patch, and the first conductor pillars; a second resonator including the second hole, the second circular patch, and the second conductor pillars; a third resonator including the third hole, the third circular patch, and the third conductor pillars; and a fourth resonator including the fourth hole, the fourth circular patch, and the fourth conductor pillars; A resonator filter that constitutes.
According to claim 1,
Each of the first and second substrates comprises FR4 epoxy,
The insulator is a resonator filter comprising a thermoset microwave material (TMM).
According to claim 1,
and the conductive strips are formed together when forming the first to fourth circular patches.
According to claim 1,
The lower conductive thin film is a resonator filter having a grounded co-planar waveguide (GCPW) structure.

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