KR102641206B1 - Waveguide resonator Dual-Band Filter With Wide Upper Stopband - Google Patents

Abstract

The present invention relates to a dual bandpass waveguide resonator filter with wide stop band characteristics. The resonator filter according to the present invention includes an upper conductor layer, a conductor patch disposed spaced apart below the upper conductor layer, and an upper conductor layer and a conductor patch. It includes a conductor pillar for electrical connection, a lower conductor layer spaced apart from the lower part of the conductor patch, and an outer wall arranged to surround the plurality of conductor pillars and the conductor patch while connecting the upper conductor layer and the lower conductor layer. The conductor patch is formed with a slot that separates the conductor patch into an inner conductor patch and an outer conductor patch. The conductor pillar portion includes a first conductor pillar and a plurality of second conductor pillars, where the first conductor pillar connects the inner conductor patch and the upper conductor layer, and the plurality of second conductor pillars connect the outer conductor patch and the upper conductor layer. It is arranged to surround the first conductor pillar.

Description

{Waveguide resonator Dual-Band Filter With Wide Upper Stopband}

The present invention relates to a waveguide resonator filter, and more specifically to a dual band-pass waveguide resonator filter.

Recently, as compact wireless communication systems are pursued, the volume allocated to individual RF elements constituting the transmitting and receiving ends of the wireless communication system is being limited. In the case of general air-filled waveguide resonator filters, there is a disadvantage of being very bulky, so preference for substrate-integrated waveguide resonator filters is increasing.

The substrate-integrated waveguide resonator structure refers to a structure in which a resonator is inserted into a substrate (dielectric). In this case, the outer wall of the resonator is generally composed of via-holes to prevent the field of the input signal entering the resonator from leaking out. At this time, the spacing between via-holes is determined according to the frequency (the higher the frequency, the closer the spacing between via-holes becomes).

Figure 1 is a diagram to explain the operating principle of a post-loaded board-integrated waveguide resonator.

Referring to Figure 1, a resonator with a copper post located inside a substrate-integrated waveguide resonator is called a post-loaded substrate-integrated waveguide resonator, and its operating principle is the inductance formed by the post and the capacitance gap formed between the post and ground. It operates in a resonance manner.

The copper patch in Figure 1 is connected to the post and serves to form a strong capacitance between the post and ground (provides the effect of increasing the cross-sectional area of the capacitor). Because the copper post inserted in the center of the resonator increases the separation distance between the first and second resonance modes, excellent stopband characteristics can be obtained.

FIG. 2 is a diagram provided to compare and explain the stopband characteristics of substrate-integrated waveguide resonator filters.

Figure 2(a) shows a case where a post is inserted inside a substrate-integrated waveguide resonator, and Figure 2(b) shows a case where a post is not inserted inside a substrate-integrated waveguide resonator.

When a post is inserted inside a substrate-integrated waveguide resonator, the peak (resonance of the high-order mode) formed due to the target passband and the next higher-order mode is higher in the case (Figure 2(a)) than in the case not (Figure 2(b)). ) is formed wider. The wider the separation distance between the target passband and the peak formed by the next higher order mode, the more excellent stopband characteristics it has, which means that it suppresses unwanted signals well at frequencies adjacent to the target passband. This is because if a peak formed due to a higher order mode is formed near the passband, suppression is impossible if a signal comes in at a frequency adjacent to the passband. At this time, the reason why the second passband occurs is because of the high-order resonance mode occurring inside the resonator.

Recently, wireless communication systems have been developed to perform multiple functions, unlike before, which only performed one function. In order to perform multiple functions, wireless communication systems often utilize more than one frequency band simultaneously, and to design such a wireless communication system, a dual band-pass filter with two pass bands is required.

Figure 3 shows a comparison of frequency response characteristics between a filter with a single passband and a filter with a dual passband.

Figure 3(a) shows the frequency response characteristics of a filter with a general single passband, and Figure 3(b) shows the frequency response characteristics of a filter with two passbands (first passband and second passband). It represents.

By designing the coupling structure of the filter so that the resonance peak generated by the high-order mode described in FIGS. 2(a) and 2(b) forms a second passband, a filter with a double passband can be implemented.

However, the conventional post-loaded board-integrated waveguide resonator structure is a resonator characterized by an excellent stop band, and has the problem of being unsuitable for dual band-pass filter design. This is because the separation distance between the first resonance mode and the second resonance mode is wide, so it is not suitable for designing a dual band-pass filter operating in an adjacent band.

To solve this problem, improved post-loaded board-integrated waveguide resonator structures were proposed.

One of them is to design a double bandpass resonator filter by forming a cross-shaped slot in the post. However, in the case of this waveguide resonator filter structure, the frequencies of not only the second resonance mode but also the third and fourth order higher-order resonance modes are lowered, so it cannot have excellent stopband characteristics. In order to have excellent stopband characteristics, the third and fourth order resonance modes must be used. Additional techniques to suppress higher order resonance modes such as should be applied to filter design. In addition, with the post-loaded board-integrated waveguide resonator structure that forms a cross-shaped slot in the post, the separation distance between the two adjustable pass bands is limited. In the case of resonance modes that resonate sequentially in a resonator, it is difficult to independently adjust only one pass band because it is mainly determined by the dimension of the resonator.

The other is to design a double bandpass resonator filter by forming two capacitance gaps on the top and bottom of the conventional resonator. However, this resonator structure, unlike the previously described resonator structure with a cross-shaped slot in the post, has the advantage of having excellent stopband characteristics and enabling a double bandpass filter design. However, because an additional substrate is needed to form an additional capacitance gap, there are disadvantages in terms of cost and manufacturing process.

The technical problem to be solved by the present invention is to provide a dual bandpass filter with wide stopband characteristics.

The resonator filter according to the present invention for solving the above-described technical problem includes an upper conductor layer, a conductor patch disposed spaced apart below the upper conductor layer, and a conductor pillar portion electrically connecting the upper conductor layer and the conductor patch. , a lower conductor layer spaced apart from the lower portion of the conductor patch, an outer wall disposed to surround the plurality of conductor pillars and the conductor patch while connecting the upper conductor layer and the lower conductor layer.

The conductor patch is formed with a slot that separates the conductor patch into an inner conductor patch and an outer conductor patch.

The conductor pillar portion includes a first conductor pillar and a plurality of second conductor pillars.

The first conductor pillar connects the inner conductor patch and the upper conductor layer.

The plurality of second conductor pillars connect the external conductor patch and the upper conductor layer and are arranged to surround the first conductor pillar.

The conductor patch may be a circular conductor plate in which the slot is formed in a ring shape at the center.

The separation distance between the resonant frequency of the first pass band and the resonant frequency of the second pass band of the resonator filter may decrease as the diameter of the internal conductor patch increases.

The first pass band may be due to the first resonance mode having the lowest resonance frequency, and the second pass band may be due to the first' resonance mode having the second lowest resonance frequency.

The first resonance mode may generate a magnetic field rotating in the same direction in the internal space and external space divided by the plurality of second conductor pillars.

The first' resonance mode may generate magnetic fields rotating in different directions in the internal space and external space divided by the plurality of second conductor pillars.

The resonator filter may further include a first substrate disposed below the upper conductor layer, and a second substrate disposed below the first substrate and above the lower conductor layer.

The first conductor pillar and the plurality of second conductor pillars may be formed to penetrate the first substrate.

The conductor patch may be disposed on the lower surface of the first substrate or the upper surface of the second substrate.

The outer wall includes a plurality of first through vias arranged to penetrate the first substrate and surround the conductor pillar portion, and a plurality of second through vias arranged to correspond to the plurality of first through vias while penetrating the second substrate. Can contain vias.

The first through via and the second through via are formed by plating the inner wall of a hole penetrating the first substrate and the second substrate with a conductive material, or a conductive material penetrating the first substrate and the second substrate. It can be formed from materials.

According to the present invention, it is possible to provide a dual bandpass filter that is compact and has wide stopband characteristics. In addition, it is advantageous in terms of manufacturing cost and manufacturing convenience compared to the conventional post-loaded board-integrated waveguide resonator filter. Additionally, the separation distance between the two pass bands can be freely adjusted.

Figure 1 is a diagram to explain the operating principle of a post-loaded board-integrated waveguide resonator.
FIG. 2 is a diagram provided to compare and explain the stopband characteristics of substrate-integrated waveguide resonator filters.
Figure 3 shows a comparison of frequency response characteristics between a filter with a single passband and a filter with a dual passband.
Figure 4 is an exploded perspective view to explain a dual bandpass waveguide resonator filter according to an embodiment of the present invention.
FIG. 5 is a side cross-sectional view of the waveguide resonator filter shown in FIG. 4 viewed from the AA' direction.
FIG. 6 shows the magnetic field distribution of the first resonance mode generated in the waveguide resonator filter shown in FIG. 4.
FIG. 7 is a diagram showing the magnetic field distribution of the first' resonance mode generated in the waveguide resonator filter shown in FIG. 4.
Figure 8 is a graph showing the separation distance between the first resonant frequency and the second resonant frequency according to the diameter of the internal conductor patch of the resonator filter according to the present invention.

Specific structural or functional descriptions of the embodiments according to the concept of the present invention disclosed in this specification are merely illustrative 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 can make various changes and have various forms, the embodiments will be illustrated in the drawings and described in detail in this specification. However, this is not intended to limit the embodiments according to the concept of the present invention to specific disclosed forms, and includes all changes, equivalents, or substitutes included in the spirit and technical scope of the present invention.

Terms such as first or second may be used to describe various components, but the components should not be limited by the terms. The above terms are used only for the purpose of distinguishing one component from another component, for example, without departing from the scope of rights according to the concept of the present invention, a first component may be named a second component and similarly a second component The component may also be named a first component.

When a component is said to be “connected” or “connected” to another component, it is understood that it may be directly connected to or connected to that other component, but that other components may also exist in between. It should be. On the other hand, when it is mentioned that a component is “directly connected” or “directly connected” to another component, it should be understood that there are no other components in between. Other expressions that describe the relationship between components, such as “between” and “immediately between” or “neighboring” and “directly adjacent to”, should be interpreted similarly.

The terms used in this specification are merely used to describe specific embodiments and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, terms such as “comprise” or “have” are intended to designate the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in this specification, but are not intended to indicate the presence of one or more other features. It should be understood that this does not exclude in advance the possibility of the existence or addition of elements, numbers, steps, operations, components, parts, or combinations thereof.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the technical field to which the present invention pertains. Terms as defined in commonly used dictionaries should be interpreted as having meanings consistent with the meanings they have in the context of the related technology, and unless clearly defined in this specification, should not be interpreted in an idealized or overly formal sense. No.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings attached to this specification. However, the scope of the patent application is not limited or limited by these examples. The same reference numerals in each drawing indicate the same members.

FIG. 4 is an exploded perspective view for explaining a resonator filter according to an embodiment of the present invention, and FIG. 5 is a side cross-sectional view of the resonator filter shown in FIG. 4 viewed from the direction A-A'.

Referring to FIGS. 4 and 5, the resonator filter 100 according to an embodiment of the present invention includes a vertically stacked upper conductor layer 110, a first substrate 120, a second substrate 130, and a lower conductor layer. It may include (140).

The upper conductor layer 110 may be implemented as a conductor plate disposed on the top of the resonator filter 100. The top conductor layer 110 may serve as a top ground layer in the resonator filter 100. Depending on the embodiment, a coupling slot, etc. may be formed in a portion of the conductor plate forming the upper conductor layer 110.

The first substrate 120 is disposed below the upper conductor layer 110. The first substrate 120 may be formed with a conductor pillar 122 and an outer wall 121.

The conductor pillar portion 122 may be composed of a plurality of conductor pillars 122a and 122b that electrically connect the upper conductor layer 110 and the conductor patch 132 disposed on the lower part of the first substrate 120. The conductor pillars 122a and 122b may have a pillar shape and be made of a conductive material. For example, the conductor pillars 122a and 122b may be implemented in a cylindrical shape. Conductive materials may include copper, brass, silver, gold, etc.

The conductor pillar portion 122 may be disposed in the center of the outer wall 121 and surrounded by the outer wall 121.

The plurality of conductor pillars 122b may be arranged at regular intervals from each other in a circle or near-circle shape and may surround the conductor pillar 122a.

The outer wall 121 may be composed of a plurality of through vias 121a arranged at predetermined intervals to surround the conductor pillar portion 122 and the conductor patch 132.

The through via 121a is formed by plating the inner wall of a via-hole that penetrates the first substrate 120 in the vertical direction with a conductive material, or is formed by a conductive pin that penetrates the first substrate 120 in the vertical direction. A material such as a (pin) may be inserted into the first substrate 120 to form the outer wall 121.

The distance between the through vias 121a may vary depending on the embodiment. For example, the outer wall 121 may be formed to connect the through vias 121a as one with no gaps between them.

The second substrate 130 is disposed below the first substrate 120. An outer wall 131 is formed inside the second substrate 120. The outer wall 131 may be formed to correspond to the outer wall 121 formed on the first substrate 120.

The outer wall 131 may be composed of a plurality of through vias 131a arranged at predetermined intervals to surround the conductor pillar portion 122 and the conductor patch 132 along with the outer wall 121.

Like the through via 121a, the through via 131a is formed by plating the inner wall of a via hole penetrating the second substrate 130 in the vertical direction with a conductive material, or is formed by plating the inner wall of the via hole penetrating the second substrate 130 in the vertical direction. A material such as a conductive pin may be inserted into the second substrate 130 to form the outer wall 131.

The distance between the through vias 131a may vary depending on the embodiment. For example, the outer wall 131 may be formed to connect the through vias 131a as one with no gaps between them.

The outer walls 121 and 131 electrically connect the upper conductor layer 110 and the lower conductor layer 140, and shield the internal space surrounded by the outer walls 121 and 131 from the external space.

The conductor patch 132 may be disposed on the interface between the first substrate 120 and the second substrate 130, that is, on the lower surface of the first substrate 120 or the upper surface of the second substrate 130.

The conductor patch 132 may be arranged to be spaced apart from the first substrate 120 and the second substrate 130 on the upper conductor layer 110 and the lower conductor layer 140.

FIG. 4 shows an example in which the conductor patch 132 is disposed on the upper surface of the second substrate 130.

The conductor patch 132 may include an inner conductor patch 132a, a slot 132b, and an outer conductor patch 132c. For example, the inner conductor patch 132a and the outer conductor patch 132c can be formed by cutting the portion 133 and the slot portion 132b from the conductor plate disposed on the upper surface of the second substrate 130. Of course, the conductor patch 132 including the inner conductor patch 132a and the outer conductor patch 132c may be disposed between the first substrate 120 and the second substrate 130 by other methods than those described here.

The conductor patch 132 may be a circular conductor plate in which a slot 132b is formed in a ring shape at the center. The ring-shaped slot 132b allows the inner conductor patch 132a to have a circular plate shape, and the outer conductor patch 132c to have a donut-shaped plate shape.

The inner conductor patch 132a is connected to the upper conductor layer 110 through the conductor pillar 122a.

The external conductor patch 132c is connected to the upper conductor layer 110 through a plurality of conductor pillars 122b.

A lower conductor layer 140 may be disposed below the second substrate 130 .

The lower conductor layer 140 may be implemented as a conductor plate disposed at the bottom of the resonator filter 100. The lower conductor layer 140 may serve as a top ground layer in the resonator filter 100. Depending on the embodiment, a slot may be formed in a portion of the lower conductor layer 140.

FIG. 6 shows the magnetic field distribution of the first resonance mode generated in the waveguide resonator filter shown in FIG. 4, and FIG. 7 shows the magnetic field distribution of the 1st 'resonant mode generated in the waveguide resonator filter shown in FIG. 4. This is the drawing shown.

The first resonance mode shown in FIG. 6 represents the most basic primary resonance mode generated by the resonator filter 100. The pass band by the first resonance mode has the lowest resonance frequency. The first resonance mode generates a magnetic field rotating in the same direction in the internal space and external space divided by the plurality of conductor pillars 122b.

The first 'resonance mode shown in FIG. 7 represents a new first 'resonance mode that is additionally generated in the resonator filter 100 by forming a ring-shaped slot 132b in the conductor patch 132. The pass band of the 'first' resonance mode has the second lowest resonance frequency compared to other resonance modes occurring in the resonator filter 100. The 'first' resonance mode generates magnetic fields rotating in different directions inside and outside the plurality of conductor pillars 122b.

The 'first' resonance mode has a resonance frequency closer to the first resonance mode than the second resonance mode generated in the resonator filter 100. Therefore, if a double band-pass filter is designed using the first resonance mode and the 'first' resonance mode occurring in the conductor patch unit 130, a double band-pass filter can be designed while maintaining a wide separation distance from the secondary resonance mode. do.

Figure 8 is a graph showing the separation distance between the first resonant frequency and the second resonant frequency according to the diameter of the internal conductor patch of the resonator filter according to the present invention.

Referring to Figures 5 and 8, they show the separation distance between the first resonance mode and the first' resonance mode according to the diameter (d) of the internal conductor patch 132a. That is, the separation distance between the resonance frequency of the first pass band by the first resonance mode and the resonance frequency of the second pass band by the first 'resonance mode decreases as the diameter d of the internal conductor patch 132a increases. You can check that. Therefore, the separation distance between the two pass bands formed by the first resonance mode and the 'first' resonance mode can be freely designed by adjusting the diameter d of the internal conductor patch 132a.

Above, embodiments of the present invention have been described with reference to the attached drawings, but those skilled in the art will understand that the present invention can be implemented in other specific forms without changing its technical idea or essential features. You will understand that it exists. Therefore, the embodiments described above should be understood in all respects as illustrative and not restrictive.

The present invention has been described with reference to the embodiments shown in the drawings, but these are merely illustrative, and those skilled in the art will understand that various modifications and other equivalent embodiments are possible therefrom. For example, the described techniques are performed in a different order than the described method, and/or components of the described system, structure, device, circuit, etc. are combined or combined in a different form than the described method, or other components are used. Alternatively, appropriate results may be achieved even if substituted or substituted by an equivalent. Therefore, the true scope of technical protection of the present invention should be determined by the technical spirit of the attached registration claims.

Claims (8)

An upper conductor layer, a conductor patch disposed spaced apart from a lower portion of the upper conductor layer, a conductor pillar portion electrically connecting the upper conductor layer and the conductor patch, a lower conductor layer disposed spaced apart from a lower portion of the conductor patch, In a resonator filter comprising an outer wall arranged to surround the conductor pillar portion and the conductor patch while connecting the upper conductor layer and the lower conductor layer,
The conductor patch is formed with a slot that separates the conductor patch into an inner conductor patch and an outer conductor patch,
The conductor pillar portion includes a first conductor pillar and a plurality of second conductor pillars,
The first conductor pillar connects the inner conductor patch and the upper conductor layer,
The plurality of second conductor pillars connect the external conductor patch and the upper conductor layer and are arranged to surround the first conductor pillar.
In paragraph 1,
The conductor patch is a resonator filter that is a circular conductor plate in which the slot is formed in a ring shape at the center.
In paragraph 2,
The resonator filter wherein the separation distance between the resonant frequency of the first pass band and the resonant frequency of the second pass band of the resonator filter decreases as the diameter of the internal conductor patch increases.
In paragraph 3,
The first pass band is due to the first resonance mode with the lowest resonance frequency,
A resonator filter in which the second pass band is caused by a first' resonance mode with the second lowest resonance frequency.
In paragraph 4,
The first resonance mode generates a magnetic field rotating in the same direction in the internal space and external space divided by the plurality of second conductor pillars,
The first' resonance mode is a resonator filter that generates magnetic fields rotating in different directions in an internal space and an external space divided by the plurality of second conductor pillars.
In paragraph 1,
a first substrate disposed below the upper conductor layer, and
A second substrate disposed below the first substrate and above the lower conductor layer.
It further includes,
The first conductor pillar and the plurality of second conductor pillars are formed to penetrate the first substrate,
The conductor patch is a resonator filter disposed on a lower surface of the first substrate or an upper surface of the second substrate.
In paragraph 6:
The outer wall is,
A plurality of first through vias arranged to penetrate the first substrate and surround the conductor pillar portion, and
A plurality of second through vias disposed to correspond to the plurality of first through vias while penetrating the second substrate.
A resonator filter containing a.
In paragraph 7:
The first through via and the second through via are:
The inner wall of the hole passing through the first substrate and the second substrate is formed by plating with a conductive material, or
A resonator filter formed of a conductive material penetrating the first substrate and the second substrate.