KR20180072977A - Waveguide filter - Google Patents

Abstract

The present invention relates to a waveguide filter comprising: a cavity part implemented in a form of a metal cap forming a part corresponding to a side surface and an upper part of a cavity to form a cavity corresponding to a resonance terminal in a form of at least one waveguide filled with air; a substrate part joined to the cavity part at a lower side of the cavity part and forming an input port and an output port of a printed circuit board (PCB) structure for signal input and output of the cavity part; and at least one dot pin structure forming a depression part pushed into the cavity part at a part corresponding to at least one resonance terminal of an upper side of the cavity part.

Description

Waveguide filter {WAVEGUIDE FILTER}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio frequency filter that can be used for radio signal processing in a mobile communication system, a satellite communication system, a radar system, and the like, and more particularly to a waveguide filter.

[Notation]

This work was supported by the Giga KOREA project of the Ministry of the Future Creation Science (Unique Project Number: 1711021003, Part Number: GK16NI0100) [This work was supported by 'The Cross-Ministry Giga KOREA Project' grant from the Ministry of Science, ICT and Future Planning, Korea.]

In recent years, in order to provide various advanced services such as Internet of Things (IoT), Vehicle to X (V2X) and hologram, a higher transmission capacity is required in a mobile communication system. Accordingly, although a greater bandwidth is required in a mobile communication system, it is difficult to accommodate a required transmission capacity due to limitations of bandwidth in a conventional microwave band. Therefore, in recent mobile communication systems, there is a technique to utilize a millimeter wave having a millimeter wavelength in order to overcome the limited frequency resources. In the next generation 5G system, which is being discussed recently, a small cell backhaul system using millimeter wave such as 28GHz or 60GHz will be applied.

In order to process such a millimeter wave signal, a waveguide filter, which is mainly used in a technical field such as a radar system or a satellite communication, is used instead of a so-called 'come-line' Is more advantageous. The waveguide filter has excellent loss characteristics in a high frequency band and is easier to implement than a combline filter.

A waveguide filter is a filter that transmits energy through a waveguide using a resonant phenomenon caused by a shielded space, that is, a waveguide structure itself, and is designed such that a substantially tubular waveguide has a length corresponding to the filtering frequency characteristic. Such a waveguide filter can be classified according to the type of the dielectric material filling the waveguide and the purpose of use.

A so-called 'cavity-type' waveguide filter, in which the waveguide is filled with air. In general, the inner part has an empty metal block structure, and has the advantage that the dielectric loss is the smallest and the transmission characteristic is excellent so that high performance can be realized. However, a flange structure for coupling between waveguides (e.g., using a standard waveguide flange 'WR-15' structure in a 'V-band', such as 57 GHz to 66 GHz) is required and its size is relatively large . Further, a separate mode transition structure (for example, a TE or TM mode to a TEM mode) is required in order to combine with other electronic devices usually implemented in the form of a printed circuit board (PCB). Examples of the technique related to the cavity type waveguide filter are disclosed in U.S. Patent Publication No. 2003/0206082 entitled " WAVEGUIDE FILTER WITH REDUCED HARMONICS ", inventors: " Ming Hui Chen ", " Wei-Tse Cheng & November 6, 2003).

On the other hand, a waveguide filter in which a waveguide is filled with a dielectric other than air is formed by forming a ceramic waveguide filter in which a waveguide is realized by a ceramic and a pseudo waveguide by forming a plurality of via holes in a PCB type substrate And a waveguide filter of a SIW (Substrate Integrated Waveguide) type. This SIW type waveguide filter has a PCB structure and can realize input / output port by CPW (Coplanar Waveguide) port or the like, so that it can be easily connected with other electronic devices implemented in PCB form without a separate mode conversion structure, And the manufacturing cost is low. However, the loss due to the dielectric loss and the radiation loss is large, and the transmission characteristic is poor, making it difficult to realize a high performance. An example of the technology related to the SIW type filter is disclosed in U.S. Patent No. 8,130,063 (entitled "WAVEGUIDE FILTER", inventors: "Xiao-Ping Chen", "Ke Wu", "Dan Drolet" March 6), for example.

As described above, various structures of the waveguide filter have been proposed, and further research has been carried out to make the waveguide filter compact and high in performance.

According to at least some embodiments of the present invention, in a waveguide filter for processing millimeter waves, a structure that can be implemented in a simpler and smaller size and can have a high performance is proposed.

According to at least some embodiments of the present invention, a structure capable of having a characteristic tuning structure in a miniaturized waveguide filter that processes millimeter waves is proposed.

According to an aspect of the present invention, there is provided a waveguide filter comprising: A cavity part formed in the form of a metal cap forming a portion corresponding to a side surface and an upper surface of the cavity to form a cavity corresponding to at least one resonance end in the form of a waveguide filled with air; A substrate part connected to the cavity part from a lower side of the cavity part and forming an input port and an output port of a printed circuit board (PCB) substrate structure for signal input / output of the cavity part; And at least one dot peen structure formed on the upper side of the cavity part to form a recessed part that is pushed into the cavity part at a position corresponding to the at least one resonance end.

A plurality of metal via holes may be formed in the substrate part along a portion where the cavity part is bonded to the substrate part to form a pseudo waveguide corresponding to a region of the waveguide formed by the cavity part.

The cavity part forms a plurality of rectangular parallelepiped resonance ends, and iriss having a connecting path structure may be formed between the plurality of resonance ends.

Wherein the cavity part comprises at least one body layer forming a hollow region corresponding to a planar region of a waveguide type resonance end that is etched with a thin metal plate to be filled with the air, And at least one cover layer sealing the region.

The dot pin structure may be formed at a central portion of each resonant end of the cavity part, and a plurality of dot pin structures formed for each resonant end may be distributed as a whole.

As described above, the waveguide filter according to the embodiments of the present invention can perform or facilitate the tuning operation to compensate the machining tolerance in a miniaturized filter structure for processing millimeter waves. Particularly, the tuning operation can be performed in an automated process, thereby reducing tuning work time and cost. In addition, since a separate mode conversion structure for the TEM mode conversion is not required, it is possible to manufacture a more compact filter, and it is possible to maintain the high performance while minimizing the processing work, thereby reducing the processing cost and improving the yield.

1 is a partially exploded perspective view of a waveguide filter according to a first embodiment of the present invention;
FIG. 2 is a perspective view of the waveguide filter of FIG.
FIG. 3 is a perspective view of the cavity part of the waveguide filter of FIG.
Fig. 4 is an enlarged view of the input port portion of the waveguide filter of Fig.
Fig. 5 is a cross-sectional view of one side of the waveguide filter of Fig. 1
6 is a schematic diagram of a tuning device for tuning the characteristics of the waveguide filter of Fig.
FIG. 7 is a partial perspective view of a first modification of the first embodiment of the present invention shown in FIG.
8 is a cross-sectional view
Fig. 9 is a plan view
Fig. 10 is a partial perspective view of a second modification of the first embodiment of the present invention shown in Fig. 1
11 is a partially exploded perspective view of a waveguide filter according to a second embodiment of the present invention.
12 is an exploded perspective view of a cavity part of a waveguide filter according to a third embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the accompanying drawings, the same reference numerals have been given to the same components as much as possible, and their sizes and shapes have been somewhat simplified or partially exaggerated for convenience of explanation.

FIG. 1 is a partially exploded perspective view of a waveguide filter according to a first embodiment of the present invention , in which a cavity part 20 and a substrate part 10 are separated from each other. FIG. 2 is a combined perspective view of the cavity part 20 and the substrate part 10 of the waveguide filter of FIG. 1, and FIG. 3 is a bottom perspective view of the cavity part 20 of the waveguide filter of FIG. FIG. 4 is an enlarged view of a portion of the input port 120 of the waveguide filter of FIG. 1, and FIG. 5 is a cutaway view of one side of the waveguide filter of FIG. 1, for example, a cut plane AA 'of FIG.

1 to 5, a waveguide filter according to a first embodiment of the present invention includes a cavity part 20 implemented as a metal cap and implementing a waveguide function for resonance and signal propagation; And a substrate part 10 having input / output ports 120 and 130 of a PCB (Printed Circuit Board) substrate structure for signal input / output of the cavity part 20. Such a structure can be seen, for example, as a structure that effectively combines these structures by taking advantage only of the conventional ordinary cavity type filter structure and the SIW type filter structure, respectively.

The cavity part 20 is embodied in the form of a metal cap forming a portion corresponding to a side surface and an upper surface of the cavity to form a cavity corresponding to at least one resonance end of a generally rectangular parallelepiped shape filled with air. In general, the cavity type waveguide filter can be composed of a rectangular parallelepiped resonance end which generates resonance at a desired frequency and iriss, which are a connection channel structure between the resonance ends. 2, in the structure according to the first embodiment of the present invention, the cavity part 20 is formed by the first iris 211 and the second iris 212, And the third resonance stages 201, 202, and 203 are configured to have a structure in which they are connected to each other in a line. At this time, the first resonant stage 201 may be a signal input single, and the third resonant stage 203 may be a signal output single. As described above, the cavity part 20 shown in FIG. 1 and the like is a structure in which the first to third resonance stages 201, 202 and 203 are connected to each other in a line, for example, However, in another modification of the present invention, it is needless to say that the filter can be designed in four or more stages, one stage or two stages depending on the number of resonance stages connected in series.

In the above structure, the cross-sectional shape of the cavity part 20, that is, the cross-sectional shape of the waveguide may be generally rectangular (square or rectangular), and the width and the length of the waveguide inner surface are determined by the cutoff frequency characteristic And can be designed to a substantially normalized value according to the filtering frequency. The waveguide lengths of the first to third resonance stages 201, 202 and 203 are appropriately designed to be, for example, 2 / ?, 4 / ?, 8 /?, Etc. according to the wavelength? . Also, by appropriately designing the intervals of the connection passages by the first and second iris 211 and 222 between the respective resonance ends, the amount of signal coupling between the resonance ends is appropriately set.

The cavity part 20 may be made of, for example, an aluminum-based material, a copper-based material, or a magnesium-based material. In some cases, the cavity part 20 may be silver plated at least on the inner surface thereof. In addition, the cavity part 20 may be formed by a deep drawing method, a mold method such as an injection mold or extrusion, or may be formed by cutting. In the case of manufacturing the cavity part 20 by using the extrusion mold method, for example, the side part of the cavity part 20 is manufactured by the extrusion mold method, the upper part of the plate part of the cavity part 20 is separately made , Or by attaching them by soldering or the like. The waveguide filter according to the present invention fabricated as described above can be subjected to frequency tuning operations as described later, so that a high degree of processing accuracy may not be required.

The substrate part 10 can be implemented according to a general PCB substrate structure and a manufacturing method. The substrate part 10 includes a substrate upper layer 102 and a substrate lower layer 106 which are metal conductor layers, and a substrate inner layer (not shown) 104). Circuit patterns of the input port 120 and the output port 130 are formed on the substrate upper layer 102 for signal input and output with the first resonant end 201 and the third resonant end 203 of the cavity part 20 respectively do.

In more detail, the substrate part 10 may be manufactured using various types of PCB structures such as commonly used FR4 (FR: Flame Retardant) type. For example, a general PCB may be formed by basically including a substrate inner layer made of glass, epoxy, synthetic resin, Teflon, a ceramic, or the like, and a copper foil layer adhered to the upper and lower surfaces of the substrate inner layer. In this manner, a general PCB can be used to manufacture the substrate part 10 of the present invention. In addition, in the substrate part 10 of the present invention, a synthetic resin layer such as plastic is formed on the substrate inner layer 104, It may be possible to implement a substrate upper layer 102 and a substrate lower layer 106 on which a metal layer (of various materials in addition to the copper foil layer) is formed.

The input port 120 and the output port 130 formed in the upper substrate layer 102 of the substrate part 20 have substantially the same structure and can be implemented in a CPW (Coplanar Waveguide) line structure. 4, the input port 120 of the CPW line structure has' A 'shape, and the input ports 120 of the CPW line structure each have a' A first slot 122 and a second slot 122, 124 formed side by side. The first and second slots 122 and 124 are formed in such a manner that the metal layer is removed from the upper substrate layer 102, which is a metal layer. The metal layer (portion a1 in FIG. 4) between the portions formed in parallel with each other in the first and second slots 122 and 124 implements the center conductor of the feed line, for example. The remaining portions (portions a2 and a3 in FIG. 4) in the first and second slots 122 and 124 transmit signals to the first resonant end 201 by inductive coupling. And the rest of the upper portion of the substrate 102 forms a ground.

In this way, in the input port 120 and the output port 130 implemented in the CPW line structure, the length and size of each part of each slot implementing the CPW line structure are appropriately designed according to the corresponding filtering frequency. The input port 120 and the output port 130 may be formed in a microstrip line structure in addition to the CPW line structure.

As described above, after the substrate part 10 and the cavity part 20 are respectively formed, the cavity part 20 is fixedly mounted on the upper part of the substrate part 10, that is, the upper substrate layer 102. A soldering lead is applied to a portion of the upper substrate 102 where the cavity part 20 is to be joined using a metal mask or the like and the substrate part 102 is heated using a heating plate or a reflow process, (10) and the cavity part (20). Of course, it is also possible to join the substrate part 10 and the cavity part 20 using a screw coupling method, laser welding or the like.

After the substrate part 10 and the cavity part 20 are combined, the cavity part 20 may be further provided with a frequency tuning structure for frequency tuning according to a feature of the present invention. 5, in the present invention, the filtering characteristic is optimized while monitoring the corresponding filtering characteristic at the time of frequency tuning, or the height of the waveguide formed by the cavity part 20 until the reference value is satisfied At least one (usually a plurality of) dot peen structures (not shown) are formed on the upper side of the cavity part 20 by adjusting the external steering gear (reference numeral 5 in Fig. 6) (232). 5 shows a state in which the dot pin structure 232 forms a recessed portion that is pushed into the interior of the cavity part 20 by the embossing or pressing by the embossing pin 502 of the external embossing machine. do.

6, a waveguide filter 1 according to the first embodiment of the present invention, which is an object of frequency tuning, includes a rack 5 of a steering gear 5 provided with a steering pin 502, . The embossing equipment 5 can be constituted by a conventional dot pin marking machine. The operating characteristics of the waveguide filter 1 are measured by the measuring instrument 2. To this end, the measuring instrument 2 provides an input signal of a preset frequency to the waveguide filter 1 and outputs the input signal to the waveguide filter 1 ). The operating characteristics of the waveguide filter 1 measured by the measuring instrument 2 are provided to the control equipment 3 which can be implemented by a PC or the like. The control equipment 3 monitors the operation characteristics of the waveguide filter 1 and controls the operation of the steering equipment 5 until the filtering characteristic is optimized or the reference value is satisfied so that the steering equipment 5, A dot pin structure 232 having an appropriate number and shape is formed on the upper side of the cavity part 20 of the filter 1.

The frequency tuning apparatus shown in FIG. 6 shows a basic configuration in which a manual operation is performed by an operator. In addition, such a frequency tuning apparatus may be implemented as an entirely automated system. For example, the embossing device 5 may be implemented as an automatic machine such as a robot arm and automatically controlled according to a preset program. At this time, the filtering characteristic of the waveguide filter 1 to be tuned can be automatically tuned to match the previously stored frequency tuning value.

The dot pin structure 232 may be formed at each resonance end of the cavity part 20, for example, at a central portion of each resonance end, and a plurality of dot fin structures may be formed in a circular shape as a whole . The material, thickness, size, and the like of the cavity part 20 are appropriately set so that undesired deformation does not occur in the stress due to the frequency tuning operation in which the dot pin structure 232 is formed. In this case, the cavity part 20 is made of a copper material having a higher elongation than aluminum, for example, so that the dot pin structure 232 is more easily formed, It can be configured to reduce the impact. Various variable amounts of frequency characteristics may appear depending on differences in width, thickness, or shape of the entire depressed portion formed by the dot pin structures 232 in the cavity part 20. The detailed detailed structure of the overall depression formed by the dot pin structure 232 can be appropriately designed according to the characteristics and conditions required for the waveguide filter 1 to be designed.

As shown in FIGS. 1 to 6, the waveguide filter according to the first embodiment of the present invention, which can be configured, can reduce cost, realize miniaturization, realize a high-performance filter, integrate with other equipment ) And ease of use. That is, in the waveguide filter according to the first embodiment of the present invention, the substrate part 10 can be easily implemented using a general PCB and substrate manufacturing process, and the cavity part 20 can be formed by simple deep drawing It can be manufactured by applying injection mold or extrusion mold. In general, when a waveguide filter for processing a millimeter wave is used, it is not useful to apply a tuning structure such as a general tuning screw. Therefore, the tuning operation depends on a high-precision manufacturing process so as to have a machining tolerance that does not require a tuning operation. As described above, in order to realize a waveguide filter that processes a millimeter wave as an actual product, very high processing accuracy is required. In contrast, in the present invention, it is possible to manufacture a cavity part having a frequency tuning structure through a relatively simple process, and compensation for mold manufacturing tolerance can be performed through the frequency tuning structure, The production yield can be improved. In addition, the waveguide filter according to the first embodiment of the present invention does not require a flange structure, which is required for connection between the waveguides in the conventional cavity type waveguide filter, and an assembly screw for coupling the flange structure , And can be implemented with a very light and simple structure. For example, in the present invention, the cavity part may be implemented with a thickness of about 1 T (mm). In addition, compared to the conventional cavity type waveguide filter, CPW ports can be used to easily connect to other electronic devices implemented in a PCB form without a separate mode conversion structure. In comparison with the conventional SIW type (PCB type) waveguide filter, dielectric loss and radiation loss are small, frequency tuning is possible, and manufacturing tolerance can be compensated by frequency tuning.

FIG. 7 is a partial perspective view of the input port (or only the output port portion) of the first modification of the first embodiment of the present invention shown in FIG. 1, and the illustration of the cavity part 20 is omitted for convenience of explanation. Fig. 8 is a cross-sectional view of one side of Fig. 7, for example, taken along the line A-A 'in Fig. 7; 9 is a bottom view of Fig. 7 to 9, in the structure according to the first modification of the first embodiment, the input port and the output port basically have a microstrip-waveguide transition structure, and more specifically, And a coaxial pin (probe) is inserted between the strip line and the waveguide to transmit a signal. The input port and the output port having such a microstrip-waveguide conversion structure can be implemented with the same structure. In FIGS. 7 to 9, the input port is shown as an example.

7 to 9, the input port is fixedly mounted on the substrate part, and the input signal provided from the microstrip line 162 is input to a probe (not shown) which radiates a signal into a waveguide formed by the cavity part 20. [ (170); And a microstrip line 162 formed in a lower layer of the substrate for transmitting an input signal to the probe 170. The probe 170 may correspond to an inner conductor of the coaxial line and may be provided in a manner to penetrate the upper substrate layer 102 and the lower substrate inner layer 106 so that the microstrip line 162 formed in the lower layer of the substrate may be soldered And can be fixedly installed. At this time, the upper substrate layer 102 of the substrate part may be uniformly formed as a conductive metal layer to form a ground, and substantially the microstrip line 162 and the auxiliary ground pattern 164 Only a metal pattern can be formed.

In addition, a plurality of via holes 180 may be formed to surround the probe 170, except for a portion where the microstrip line 162 is formed. A plurality of via holes 180 are formed in the lower layer of the substrate in correspondence with the portions where the plurality of via holes 180 are formed. The plurality of via holes 180 pass through the substrate inner layer 104, which is a non- And the upper ground layer 102 and the auxiliary ground pattern 164 are electrically connected to each other. The plurality of via holes 180 form a grounded area as a whole, thereby blocking open signals that are likely to flow out through the substrate part at the probe 170.

Fig. 10 is a partial perspective view of a second modification of the first embodiment of the present invention shown in Fig. 1, and the illustration of the cavity part is omitted for convenience of explanation. Referring to FIG. 10, in the structure according to the second modification of the first embodiment, the input port and the output port have a microstrip-waveguide conversion structure in which coaxial pins (probes) are inserted as in the case of FIGS. 7 to 9. Unlike the first modification of Figs. 7 to 9, however, In the second modification shown in FIG. 10, a microstrip line 163 connected to the probe 170 is formed in the upper substrate layer 102. That is, the upper substrate layer 102 is entirely formed of a conductive metal layer except for the patterned portion of the microstrip line 163, and the probes 170 are formed on the microstrip line 163 formed in the upper substrate layer 102 And is fixed by soldering or the like. The structure according to the second modification shown in FIG. 10 does not have a structure corresponding to the plurality of via holes 180 described in the first modification shown in FIGS. 7 to 9. 7 to 9, a plurality of via holes are formed between the upper substrate layer 102 and the lower substrate layer 104 so as to surround the probes 170 in order to improve the grounding property, .

11 is a partially exploded perspective view of a waveguide filter according to a second embodiment of the present invention . 11, the waveguide filter according to the second embodiment of the present invention is implemented in the form of a metal cap and has a waveguide function for resonance and signal propagation, as in the structure of the first embodiment shown in Figs. 1 to 6 A cavity part (20) for realizing the cavity part (20); And a substrate part 10 having input / output ports 120 and 130 of a PCB substrate structure for signal input / output of the cavity part 20. The cavity part 20 has a dot pin structure for frequency tuning as in the first embodiment and an input port 120 and an output port 130 having a CPW port structure are formed on the substrate part 10 .

11, in addition to the structure of the first embodiment, the waveguide filter according to the second embodiment may include a plurality of metal via holes 150, similar to the conventional SIW type structure, A pseudo waveguide is formed. 11 shows a side cut structure of each metal via hole 150. Each of the metal via holes 150 passes through the substrate inner layer 104 which is a nonconductive layer of the substrate part 10, And a structure in which the upper substrate layer 102 and the lower substrate layer 106 are electrically connected.

0.5]의 조건을 만족하도록 설정된다. 이러한 구조에 따라 다수의 금속 비아홀(150), 기판 상층(102) 및 기판 하층(106)에 의해 정의되는 (유전체) 기판 내층(104)의 해당 영역은 도파관 영역(즉, 의사 도파관)을 형성하게 된다. A plurality of metal via holes 150 may be formed in the cavity portion 20 in order to form a pseudo waveguide corresponding to a region of the waveguide formed by the cavity portion 20, Substantially the cavity portion 20 is formed along the portion to be bonded to the substrate part 10. [ The spacing s between adjacent metal via holes 150 is greater than the radius r of the via hole 150 by [r / s

0.5] is satisfied. According to this structure, the corresponding region of the (dielectric) substrate inner layer 104 defined by the plurality of metal via holes 150, the upper substrate layer 102 and the lower substrate layer 106 forms a waveguide region do.

The structure according to the second embodiment shown in FIG. 11 further includes a waveguide structure similar to that of the SIW type in the substrate part 10, so that the height of the waveguide filter in the overall size of the waveguide filter You can reduce it further.

FIG. 12 is a cross-sectional view of a cavity of a waveguide filter according to a third embodiment of the present invention. It is an exploded perspective view of the part. Referring to FIG. 12, the cavity part of the waveguide filter according to the third embodiment of the present invention is implemented in a laminated form of a metal plate, which is slightly different from the structure of the first embodiment shown in FIGS. 1 to 6. Although not shown in FIG. 12, the substrate part may be implemented in the same manner as the structure of the first embodiment or the structure of the second embodiment shown in FIG.

The cavity part, which is embodied as a laminate of metal plates, comprises at least one body layer having a hollow area corresponding to the planar area of the waveguide area, as shown in FIG. 12, to form a waveguide area filled with air The first and second body layers 202, 204); And at least one cover layer 206 stacked on the at least one body layer 202 and 204 to seal the free space.

The at least one body layer 202, 204 and the cover layer 206 may be formed by etching a thin metal plate, respectively, and the etched metal plates are stacked on each other to form an entire cavity part. Thus, in the formed cavity part, a dot pin structure for frequency tuning is formed on the cover layer 206, similarly to the first embodiment.

The mold structure can be saved in mass production, but in case of small quantity, the cost of molding is increased due to the mold cost. In addition, the round design is additionally required because the mold has to be rounded at every corner. However, the metal plate etch laminating method as shown in FIG. 12 is advantageous for small-scale production because it has no mold cost and can be realized without a corner round.

As described above, the waveguide filter according to the embodiments of the present invention can be constituted, while the specific embodiments of the present invention have been described in the above description. However, the present invention may have various other embodiments and modifications . For example, it will be appreciated that the various configurations of the waveguide filter, such as the number of stages of the cavity part, the detailed structure of the iris, the size, and the like, can be variously modified in consideration of the required filtering characteristics and other product designs . Thus, various modifications and variations of the present invention can be made without departing from the spirit and scope of the present invention as defined by the appended claims and their equivalents.

Claims (8)

In the waveguide filter,
A cavity part formed in the form of a metal cap forming a portion corresponding to a side surface and an upper surface of the cavity to form a cavity corresponding to at least one resonance end in the form of a waveguide filled with air;
A substrate part connected to the cavity part from a lower side of the cavity part and forming an input port and an output port of a printed circuit board (PCB) substrate structure for signal input / output of the cavity part;
And at least one dot peen structure is formed on the upper surface of the cavity part to form a recessed part that is pushed into the cavity part at a position corresponding to the at least one resonance end.
2. The semiconductor device according to claim 1, wherein the substrate part comprises a substrate upper layer and / or a substrate lower layer which is a conductor layer of a metal and a substrate inner layer which is a nonconductive layer,
Wherein at least one resonance end of the cavity part and a circuit pattern of the input port and the output port are formed in the upper layer of the substrate to input and output signals, respectively.
[3] The apparatus of claim 2, wherein the substrate part is formed with a plurality of metal via holes along a portion where the cavity part is bonded to the substrate part to form a pseudo waveguide corresponding to a region of the waveguide formed by the cavity part, A waveguide filter.
The waveguide filter according to claim 2 or 3, wherein the input port and the output port are implemented by a microstrip-waveguide conversion structure or a CPW (Coplanar Waveguide) line structure.
The waveguide filter according to claim 1, wherein the cavity part forms a plurality of resonance ends in a rectangular parallelepiped shape, and irises are formed between the plurality of resonance ends in a connection passage structure.
The waveguide filter according to claim 5, wherein the cavity part is fabricated by deep drawing, injection molding, or extrusion molding.
6. The apparatus according to claim 5,
At least one body layer for etching a thin metal plate to form a hollow region corresponding to a plane region of the at least one resonance end,
And at least one cover layer laminated on the at least one body layer and sealing the hollow region.
The waveguide filter according to claim 1, wherein the dot pin structure is formed at a central portion of each resonant end of the cavity part, and a plurality of dot pin structures formed for each resonant end are distributed in a circular shape as a whole.

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