Filter for communication device

Abstract

The present invention relates to a filter for a communication device, and more particularly, to a filter for a communication device, comprising at least three adjacent resonance elements selected in order along the longitudinal direction of a cavity for multipath coupling, and a notch-forming section that is disposed so as to be closer to the distance between the adjacent resonance elements at which the magnetic field coupling prevails or the electric field coupling prevails, and that limits the region of the filter frequency by forming a prescribed notch at the left and right ends of the path band, whereby the complexity of the filter can be simplified, and the filter efficiency can be improved. And the performance of various filters can be embodied.

Description

Technical Field

[0001] The present invention relates to a filter for a communication device, and more particularly, to a filter for a communication device capable of forming a cavity by folding (doubling) in an adjacent manner in the entire process with resonators adjacent to each other, arranging a plurality of resonators spaced apart from each other inside the cavity, and forming a notch forming portion having an L-notch portion based on inductive coupling and a C-notch portion based on capacitive coupling at both ends of a frequency band path. Background Art

[0002] Radio frequency devices such as radio frequency filters (including all "communication devices") are generally configured as a connection structure of a plurality of resonators. Such a resonator is a circuit element that resonates at a specific frequency through a combination of an inductor L and a capacitor C of an equivalent circuit, and each resonator has a structure in which a dielectric resonance element (DR) or a metal resonance element is provided inside a cavity such as a metallic cylinder or a rectangular parallelepiped surrounded by a conductor. Accordingly, each resonator has a structure in which only an electromagnetic field having an inherent frequency based on a processing frequency band exists in the corresponding cavity, so that high-frequency resonance can be achieved. Generally, a plurality of cavities are used to form a plurality of resonance terminals, and a multi-stage structure in which the plurality of resonance terminals are connected in sequence is provided.

[0003] As an example related to a radio frequency filter having a multi-cavity structure, the content disclosed in Korean Patent Publication No. 10-2004-0100084 (title: "Radio Frequency Filter", publication date: December 02, 2004) previously filed by the applicant can be cited.

[0004] However, in the existing radio frequency filter, each resonator extends in the thickness direction inside the cavity, and in order to have a desired band-pass characteristic, a part of the filter tuning cover covering the cavity is deformed by stamping to tune the distance from the resonator. Therefore, there is a problem that it is very limited in reducing the size in the thickness direction of the finished filter.

[0005] In addition, in order to enhance the skirt characteristics between adjacent resonators or between spaced-apart resonators in a plurality of cavities in the existing radio frequency filter, inductive coupling or capacitive coupling is embodied, and for this purpose, an additional structure made of a conductor material needs to be provided. Therefore, there is also a problem that the weight of the finished filter is greatly increased.

[0006] On the other hand, recently, in antenna devices applying the Massive MIMO (Multiple In-put Multiple Out-put) technology, in order to achieve the ultra-thinning production of the entire product, research is being carried out in the direction of minimizing the thickness of internal structures such as filters. For this purpose, as the most commonly used type of filter, a dielectric ceramic filter can be cited.

[0007] However, due to the characteristics of its material, the dielectric ceramic filter needs to be directly adhered to and combined with a single surface of the main board (or PA board) laminated inside the antenna housing part. In this regard, there is a problem that the double-sided use of the PCB (printed circuit board) is limited. Summary of the Invention

[0008] Technical Problem

[0009] The present invention is proposed to solve the above technical problems. The object of the present invention is to provide a filter for a communication device that can form a cavity in a folding manner, construct a convenient and simple-shaped notch forming part inside with a slightly smaller size in the thickness direction, thereby ensuring various frequency characteristics, and thus facilitating the formation of design notches on both sides of the path band.

[0010] The problems of the present invention are not limited to the above-mentioned problems, and those of ordinary skill in the art can clearly understand other unmentioned problems through the following description.

[0011] Solution to the Problem

[0012] A filter for a communication device according to an embodiment of the present invention configured as described above includes: a base plate that forms a hexahedral cavity with a thickness in the front-rear direction at least smaller than the width in the left-right direction and having the up-down direction as the length direction when the radiation direction of the antenna element is defined as the front-rear direction, a plurality of resonators that form the same stacked layer with respect to the front-rear direction (thickness direction) of the cavity; and an input port part and an output port part. The input port part inputs a specified signal to the resonator at the side end closest to the length direction of the cavity among the plurality of resonators, and the output port part outputs a specified signal from the resonator at the other side end closest to the length direction of the cavity among the plurality of resonators. The filter for the communication device includes a notch forming part that is disposed inside the cavity and is arranged in a manner closer to the separation distance of a part where magnetic field coupling or electric field coupling is dominant compared to adjacent respective resonator elements among the resonator elements including the input port part, the output port part, and the plurality of resonators sequentially selected along the length direction.

[0013] Among the plurality of resonators in the resonance elements other than the input port portion and the output port portion, resonance ends serving as portions where electric field coupling is dominant (hereinafter referred to as "electric field portions") can be formed in a divided manner at the front end portions corresponding to the other end portions in the width direction which is the left - right direction. The portion where electric field coupling is dominant is a portion where the size in the length direction is relatively larger than another portion where magnetic field coupling is dominant (hereinafter referred to as "magnetic field portion").

[0014] Moreover, the notch forming portion may include: an L - notch portion, which is adjacent in such a way as to only affect the magnetic field portion entirely; and a C - notch portion, which is adjacent in such a way that a certain part affects the electric field portion.

[0015] Moreover, among the plurality of resonators arranged in sequence along the length direction, the L - notch portion and the C - notch portion can function as cross - coupling rods that achieve coupling with at least one or two or more resonators in between.

[0016] Moreover, the L - notch portion and the C - notch portion can be arranged in the cavity in the thickness direction so as to form the same stacked layer, and can be arranged in a way that forms a different stacked layer from the plurality of resonators.

[0017] Moreover, the L - notch portion can form a closed loop extending from one side in the width direction of the cavity to the other side in the width direction.

[0018] Moreover, the C - notch portion can extend from one side in the width direction of the cavity to the other side in the width direction, and is arranged adjacent to one of the resonance ends of the plurality of resonators.

[0019] Moreover, with respect to the L - notch portion, among at least 3 adjacent resonance elements sequentially selected along the length direction for multipath coupling, it is arranged in a way that is relatively closer than the separation distances of the electric field portions of the adjacent respective resonance elements, so that a prescribed notch can be formed at the right - hand end of the passband to limit the filtering frequency region.

[0020] Moreover, with respect to the C - notch portion, among at least 3 adjacent resonance elements sequentially selected along the length direction for multipath coupling, it is arranged in a way that is relatively closer than the separation distances of the magnetic field portions of the adjacent respective resonance elements, so that a prescribed notch can be formed at the left - hand end of the passband to limit the filtering frequency region.

[0021] Moreover, according to the properties of the electric field portion and the magnetic field portion that are relatively strongly expressed through adjacent coupling or the cross - coupling in the plurality of resonators, the L - notch portion and the C - notch portion can be defined by one of the L - notch portion and the C - notch portion.

[0022] Further, when the L-notch portion and the C-notch portion are respectively provided in different ranges in the longitudinal direction of the cavity, it is defined by one of the L-notch portion and the C-notch portion according to the properties of the electric field portion and the magnetic field portion in the plurality of resonators.

[0023] Further, when the L-notch portion and the C-notch portion are provided in the same range in the longitudinal direction of the cavity in a single structure, it is defined by a composite structure having the functions of both the L-notch portion and the C-notch portion according to the properties based on adjacent coupling and the properties based on cross coupling in the plurality of resonators.

[0024] Further, when including the resonant elements in which the input port portion and the output port portion are coupled, the C-notch portion may branch from the input port portion and extend in a manner of facing the resonant end of the adjacent resonator across the one-side end resonator.

[0025] Further, when including the resonant elements in which the input port portion and the output port portion are coupled, the L-notch portion may branch from the output port portion and be connected to the adjacent resonator across the other-side end resonator.

[0026] Further, the cavity may be formed into a single base plate by a folding method.

[0027] Further, the notch forming portion may be separately formed into a plate shape and formed to correspond to the structure of the base plate or combined with the inside of the cavity.

[0028] Further, the notch forming portion can be integrally provided on the base plate and be provided in a plate shape located inside the cavity when the folding is performed.

[0029] Effects of the Invention

[0030] The filter for a communication device according to an embodiment of the present invention can form a cavity by a folding method, and construct a notch forming portion in a convenient and simple form inside with a slightly smaller size in the thickness direction, thereby ensuring various frequency characteristics. Therefore, it is convenient to form design notches on both sides of the passband. Description of the Drawings

[0031] Figure 1 FIG. is a perspective view showing a filter for a communication device according to an embodiment of the present invention.

[0032] Figure 2 is Figure 1 an internal view of

[0033] Figure 3 is inFigure 1 A perspective view of the state in which the base material plate is unfolded in the structure,

[0034] Figure 4 is Figure 3 a top view of,

[0035] Figure 5 is a perspective exploded view showing an embodiment of an input terminal pin and an output terminal pin in a separately provided Figure 1 structure,

[0036] Figure 6 is a sectional perspective view taken along line A-A ([[]] Figure 6 part (a) of, Figure 6 part (b) of)

[0037] Figure 7 is a top view for explaining the notch formation principle and structure of a first embodiment of a notch formation portion in the structure of a filter for a communication device using an embodiment of the present invention,

[0038] Figure 8 is Figure 7 an internal view of,

[0039] Figure 9 is Figure 7 a circuit diagram of,

[0040] Figure 10 is a graph showing the Figure 7 frequency characteristics of,

[0041] Figure 11 A top view for explaining the notch formation principle and structure of a second embodiment of a notch formation portion in the structure of a filter for a communication device using an embodiment of the present invention,

[0042] Figure 12 is Figure 11 an internal view of,

[0043] Figure 13 is Figure 11 a circuit diagram of,

[0044] Figure 14 is a graph showing the Figure 11 frequency characteristics of,

[0045] Figure 15 is a top view for explaining the notch formation principle and structure of a third embodiment of a notch formation portion in the structure of a filter for a communication device using an embodiment of the present invention,

[0046] Figure 16 is Figure 15 an internal view of,

[0047] Figure 17 is Figure 15 the circuit diagram of

[0048] Figure 18 is for showing Figure 15 the chart of the frequency characteristics of

[0049] Figure 19 is the top view for explaining the notch formation principle and structure of the notch formation part in the structure of the filter for communication equipment according to an embodiment of the present invention

[0050] Figure 20 is Figure 19 the internal view of

[0051] Figure 21 is for showing Figure 19 the chart of the frequency characteristics of

[0052] Description of reference numerals

[0053] 100: Filter for communication equipment 105: Base plate

[0054] 110: Main body bottom forming plate 120: One - side thickness forming plate

[0055] 130: The other - side thickness forming plate 140: Notch formation part

[0056] 141: L - notch part 143: C - notch part

[0057] 145: Partition structure 150: Main body upper forming plate

[0058] 170: Multiple resonators 175A: Input port part

[0059] 175B: Output port part C: Cavity Detailed implementation manners

[0060] The following will make the advantages, features and the methods for realizing these advantages and features of the present invention more clear by referring to the embodiments described in detail with the attached Figure 1 However, the present invention is not limited to the embodiments disclosed below and can be implemented in various different ways. These embodiments only make the disclosure of the present invention complete and are used to enable those of ordinary skill in the technical field to which the present invention pertains to fully understand the scope of the present invention. The present invention is only defined by the claims. Throughout the specification, the same reference numerals denote the same structural elements

[0061] The following will specifically describe the embodiments of the present invention with reference to the drawings

[0062] Figure 1 is the perspective view showing the filter for communication equipment according to the first embodiment of the present inventionFigure 2 is Figure 1 an internal view of Figure 3 is a perspective view of the state in which the base material plate is unfolded in the structure of Figure 1 Figure 4 is Figure 3 a top view of Figure 5 is an exploded perspective view showing an embodiment of an input terminal pin and an output terminal pin in the structure provided separately Figure 1 Figure 6 is a sectional perspective view taken along line A-A ( Figure 6 part (a) of Figure 6 part (b) of

[0063] The communication antenna includes a filter for filtering signals in a specific path band. The filter can use a cavity filter, a waveguide filter, etc. according to characteristics. However, in the embodiments of the present invention, as a type of cavity filter, the description is not centered on manufacturing the filter body by the existing molding method, but on a cavity filter with a folding process in which a single base material plate is formed into a cavity as the main signal transmission path by a folding (doubling) method.

[0064] Generally, in the field of antenna technology, a filter is a communication component that plays a role of filtering only signals in a specific frequency band among signals that need to be input or output during the transceiver process, so that consumers (users) only obtain the required signals as result values.

[0065] In order to filter such signals, as its name implies, a cavity filter forms a cavity as a specified signal filtering section (signal transmission path) between the input port of the input signal and the output port of the output signal, and through the tuning process based on the frequency of the cavity, consumers obtain the specific frequency band signal values in the required section.

[0066] However, so far, in the same industry of manufacturing antenna devices, only one process has been developed and disclosed for manufacturing a cavity filter, which is to process the inside of a filter body made of a ceramic material (dielectric material) or a rigid material above it to manufacture the above-mentioned cavity, and after manufacturing essential structures such as multiple resonators for frequency filtering, fix them inside the cavity.

[0067] However, the filter for a communication device according to the embodiments of the present invention discloses an epoch-making technical feature of getting rid of the above manufacturing process, processing a single flat base material plate with a thickness not exceeding a specified thickness in a sheet metal form, and constructing the structure inside the cavity through a folding process without using an additional joining process.

[0068] ​​However, before describing the filters 100, 100A to 100D for communication devices according to the embodiments of the present invention, the shape of the cavity C and the setting position or shape of the notch forming portion 140 disposed inside thereof can be very important elements in understanding the present invention. Therefore, the definitions of terms related to directivity can be set as follows.

[0069] That is, generally, the beam radiation direction of an antenna element (radiation element) (not shown) can be defined as the front-back direction. More specifically, the antenna elements can be arranged in multiple columns in the up-down direction or the left-right direction on the front surface of an antenna housing portion (not shown).

[0070] Such antenna elements can be stacked via an antenna board assembly (not shown) on the front surface of the filters 100, 100A to 100D for communication devices according to the embodiments of the present invention disposed inside the antenna housing portion.

[0071] Among them, the cavity C of the filters 100, 100A to 100D for communication devices according to the embodiments of the present invention can be formed into a hexahedron having a size such that the thickness in the above-mentioned front-back direction is at least smaller than the width in the left-right direction and having the up-down direction as the length direction.

[0072] Therefore, in the hexahedron forming the cavity C, the front-back direction, which is the thinnest part, can be defined as the "thickness direction", the left-right direction can be defined as the "width direction", and the up-down direction can be defined as the "length direction".

[0073] A filter 100 for a communication device according to an embodiment of the present invention includes a base plate 105 made of a conductive material. The base plate 105 made of a conductive material is made in an unfolded state. When folded, a cavity C is formed inside, and it is arranged in a foldable manner so that a plurality of resonators 170 protruding a predetermined length in the thickness direction or the width direction are provided inside the cavity C.

[0074] Preferably, the base plate 105 can be made of a conductive material, but it can also be made of a non-conductive material that is easy to manufacture. And it should be noted in advance that in the future, a conductive substance can be used to form a film on both the inside and outside of the cavity C by plating so that the function of the signal transmission path (or signal filtering section) of the cavity C can be performed.

[0075] However, as will be described later, the base plate 105 changes its shape through a folding process and then needs to continuously maintain its shape without the application of an external force. In this regard, preferably, it should be made of a variable material suitable for this.

[0076] Among them, the cavity C is a dielectric-filled space filled with a dielectric having a specified dielectric constant, which means that an empty state is formed inside for the space to fill the dielectric. And it should be noted in advance that air is also a kind of dielectric with a dielectric constant of 1. In this regard, when using air in the atmospheric pressure state as the dielectric, no additional dielectric filling process is required.

[0077] On the other hand, in the filter 100 for a communication device according to an embodiment of the present invention, the base plate 105 functions to form the cavity C as a dielectric-filled space.

[0078] Among them, as Figure 3 and Figure 4 shown, the base plate 105 may include: a main body bottom forming plate 110 that forms the bottom surface of the cavity C; a side thickness forming plate 120 and an opposite side thickness forming plate 130 that extend in a plane at one end and the other end in the width direction of the main body bottom forming plate 110 to increase the length of the width, thereby increasing the size in the thickness direction of the cavity C; a resonator plate 160 that extends from the front end of one of the side thickness forming plate 120 and the opposite side thickness forming plate 130 and has a plurality of resonators 170 disposed in a protruding manner within the cavity C corresponding to the upper part of the main body bottom forming plate 110; and a main body upper forming plate 150 that extends from the front end of the other of the side thickness forming plate 120 and the opposite side thickness forming plate 130 and is arranged to cover the upper part of the cavity C facing the main body bottom forming plate 110.

[0079] At the same time, one-side shielding plates 180A and the other-side shielding plates 180B for shielding one end and the other end in the length direction of the opening of the cavity C can be integrally extended and formed at one end and the other end in the length direction of the main body bottom forming plate 110.

[0080] Here, although it is limited that the one-side shielding plates 180A and the other-side shielding plates 180B are integrally formed on the main body bottom forming plate 110, according to the embodiment, they can also be integrally provided in a symmetric manner on an adjacent plate (for example, the main body upper forming plate 150, etc.), which is natural. And the one-side shielding plates 180A and the other-side shielding plates 180B can be integrally formed on an adjacent plate so as to be divided into 2 components respectively, and can completely cover the parts of the respective opened cavities C through a folding action.

[0081] On the other hand, a plate 110 may be formed at the bottom of the main body, and an input port setting portion 115A and an output port setting portion 115B are formed at one end portion in the length direction and the other end portion in the length direction in a vertically penetrating manner, respectively. The input terminal pin 175A' described later may be penetratively provided in the input port setting portion 115A, and the output terminal pin 175B' described later may be penetratively provided in the output port setting portion 115B.

[0082] In particular, although not shown in the drawings, the input terminal pin 175A' and the output terminal pin 175B' inserted into the input port setting portion 115A and the output port setting portion 115B may be provided with Teflon having a stud or serrated protrusion shape in a surrounding manner on the outer peripheral surface, so that the insertion loss can be minimized.

[0083] Meanwhile, as Figure 3 and Figure 4 shown, the base material plate 105 may further include a notch forming portion 140. The notch forming portion 140 is provided between one of the one-side thickness forming plate 120 and the other-side thickness forming plate 130 (adopted as the other-side thickness forming plate 130 in an embodiment of the present invention) and the main body upper forming plate 150, and is disposed to extend in the horizontal direction (or thickness direction) within the cavity C.

[0084] As Figure 3 and Figure 4 shown, the notch forming portion 140 can be integrally provided on the base material plate 105, and can be set in a plate form located inside the cavity C during the folding process.

[0085] However, the notch forming portion 140 is not limited to being integrally provided on the base material plate 105 and formed through the folding process. As Figures 7 to 9 shown later, it can be separately made into a plate form and constructed in a manner corresponding to the structure of the base material plate 105 or combined inside the cavity C.

[0086] Moreover, the notch forming portion 140 does not necessarily have to be set in a plate form, but can be integrally formed at a position corresponding to the main body upper forming plate 150 within the range where the operator who performs frequency tuning in the future deforms the shape inside the cavity C, which goes without saying.

[0087] Among them, the notch forming portion 140 may include an L-notch portion 141 that forms a notch based on inductive coupling (hereinafter referred to as an "L-notch") at the right end (high-frequency region) of the path band; and a C-notch portion 143 that forms a notch based on capacitive coupling (hereinafter referred to as a "C-notch") at the left end (low-frequency region) of the path band.

[0088] The following multiple embodiments can be applied to further elaborate in detail on the formation positions and shapes of each of the L-notch portion 141 and the C-notch portion 143, as well as the formation principle of the L-notch and the C-notch based thereon.

[0089] As Figure 3 and Figure 4 shown, when the notch forming portion 140 and the main body upper forming plate 150 are provided simultaneously, the separation plate 151 on one side and the separation plate 152 on the other side for separating the notch forming portion 140 and the main body upper forming plate 150 in the thickness direction can also be integrally provided on the base material plate 105. And after separating a predetermined distance by a folding action, the lower end portion of the separation plate 152 on the other side can be used as a connection line outside, and the lower end portion of the separation plate 151 on one side can be joined to each other by butt welding.

[0090] On the other hand, multiple frequency tuning rods (refer to the reference numeral “146” in the drawings described later Figure 7 and Figure 8 ) and multiple coupling adjustment rods (refer to the reference numeral “147” in the drawings described later Figure 7 and Figure 8 ) can be integrally cut and formed on the main body upper forming plate 150. The multiple frequency tuning rods adjust the separation distance from multiple resonators 170 arranged in a single layer in the thickness direction inside the cavity C to perform fine frequency tuning, and the multiple coupling adjustment rods are respectively deformed in shape directly below between the multiple resonators 170.

[0091] Among them, the multiple frequency tuning rods 146 and the multiple coupling adjustment rods 147 can be integrally formed with the L-notch portion 141 and the C-notch portion 143 on a tuning frame (not shown with a reference numeral) having a notch forming portion 140.

[0092] More specifically, the tuning frame can be formed in a frame shape having a rectangularly arranged border. Among the four sides (four edges) of the tuning frame, multiple tuning rods 146 are formed extending from the inside of one long side toward the other long side, separated by a predetermined distance in the length direction.

[0093] And, the multiple coupling adjustment rods 147 can be integrally formed on the tuning frame and, like the multiple tuning rods 146, extend from the inside of one long side toward the other long side, with one being provided in each of the separated spaces of the multiple tuning rods 146.

[0094] On the other hand, the L-notch portion 141 and the C-notch portion 143 can extend from the inside of the other long side toward the one long side among the four sides (four edges) of the tuning frame.

[0095] Among them, the tuning framework forms the same stacked layers within the cavity C. Therefore, it is natural that the multiple tuning rods 146 and the multiple coupling adjustment rods 147 form different stacked layers with the multiple resonators 170 within the cavity C.

[0096] That is, the multiple tuning rods 146 can be configured into a single layer different from the multiple resonators 170 within the cavity C so as to adjust the separation distance from the multiple resonators 170 disposed within the cavity C.

[0097] And, a tool insertion hole (not shown) is formed through the plate 150 formed on the upper part of the main body so that the above-mentioned L-notch portion 141 and C-notch portion 143 can be deformed in shape using a specified tool, which is natural.

[0098] Among them, as Figures 2 to 6 shown, when it is assumed that the cavity C formed by folding each part of the base material plate 105 is formed to be elongated in the length direction and is an ultra-thin rectangular parallelepiped shape with a relatively very small size in the up-down thickness direction compared to the front-back width direction, the multiple resonators 170 can form the same single layer with respect to the thickness direction of the cavity C.

[0099] At the same time, the notch forming portion 140 can also form the same single layer with respect to the thickness direction of the cavity C and can form a single layer different from the above-mentioned multiple resonators 170.

[0100] However, the formation position and shape of the notch forming portion 140 are not specified and can be subjected to various designs described later according to the position and selection of the resonator related to multi-path coupling, which is natural.

[0101] Figure 7 A top view for explaining the notch forming principle and structure of the first embodiment of the notch forming portion in the structure of the filter for a communication device using an embodiment of the present invention. Figure 8 For Figure 7 the internal view of Figure 9 For Figure 7 the circuit diagram of Figure 10 For showing Figure 7 the frequency characteristics of Figure 11 A top view for explaining the notch forming principle and structure of the second embodiment of the notch forming portion in the structure of the filter for a communication device using an embodiment of the present invention. Figure 12 For Figure 11 the internal view of Figure 13 For Figure 11 the circuit diagram of Figure 14 For showing Figure 11 the frequency characteristics of Figure 15A top view for explaining the notch formation principle and structure of the notch formation part in the structure of the filter for a communication device according to a third embodiment of the present invention. Figure 16 is Figure 15 an internal view of Figure 17 is Figure 15 a circuit diagram of Figure 18 is a graph showing Figure 15 the frequency characteristics of Figure 19 A top view for explaining the notch formation principle and structure of the notch formation part in the structure of the filter for a communication device according to a fourth embodiment of the present invention. Figure 20 is Figure 19 an internal view of Figure 21 is a graph showing Figure 19 the frequency characteristics of

[0102] Generally, in order to improve the stopband attenuation characteristics of a band pass filter (BPF), a transmission-zero design using electric coupling, magnetic coupling, or mixed coupling is used between non-adjacent odd (Cascaded Triplet) or even (Cascaded Quardruplet) resonant elements (resonators).

[0103] If cross coupling is achieved across even-numbered resonant elements, transmission zeros symmetric about the left and right of the filter passband are generated. If cross coupling is achieved across odd-numbered resonant elements, usually one transmission zero occurs on the left or right side of the passband depending on the type of coupling (i.e., depending on whether it is electric coupling or magnetic coupling).

[0104] The transmission zero generated on the left side of the passband or symmetrically on both sides using electric coupling is called capacitive cross-coupling, and the transmission zero generated on the right side of the passband using magnetic coupling is called inductive cross-coupling.

[0105] Generally, the coupling that occurs in the absence of an additional notch structure shows magnetic coupling predominating between adjacent resonant elements (resonators). To achieve capacitive cross-coupling of a cavity filter, the above-mentioned additional notch structure is artificially provided.

[0106] In the structure of the communication device filter 100 according to an embodiment of the present invention, the notch forming portion 140 performs the function of the notch structure described above. In particular, in the present invention, the plurality of resonators 170 form the same stacked layers with respect to the thickness direction of the cavity C, and are arranged side by side with a predetermined distance in the length direction of the cavity C, thereby solving the problem that the notch structure of the notch forming portion 140 is very difficult to solve.

[0107] In more detail, Figures 7 to 21 As shown, in the filter 100A~100D for communication equipment of one embodiment of the present invention, when the input port portion 175A and the output port portion 175B and the plurality of resonators 170①~170⑦ are defined as "resonance elements", the notch forming portion 140 can be arranged to realize multipath coupling in a manner that is closer to each other than the spacing distance between the portions where magnetic field coupling is dominant or the portions where electric field coupling is dominant of the adjacent resonant elements, so as to form a prescribed notch at the left and right ends of the path band to limit the region of the filtering frequency.

[0108] Reference Figure 7 and Figure 8 In the plurality of resonators 170 except the input port portion 175A and the output port portion 175B in the resonance element, resonant ends 173 as a portion where electric field coupling is dominant (hereinafter referred to as an “electric field portion”) may be formed in a divided manner at the front end portion corresponding to the other end portion in the width direction, wherein the portion where electric field coupling is dominant is a portion having a larger size in the length direction than another portion where magnetic field coupling is dominant (hereinafter referred to as a “magnetic field portion”).

[0109] The notch forming portion 140 may include: L-notch portions 141 adjacent to each other in a manner that all of them affect only the magnetic field portion; and C-notch portions 143 adjacent to each other in a manner that a certain portion of them affects only the electric field portion.

[0110] However, it should be noted that whether the notch structure provided in the cavity C is defined by the L-notch portion 141 and the C-notch portion 143 is not defined by simply being physically adjacent. This will be described in more detail later.

[0111] On the other hand, among the plurality of resonators 170 sequentially arranged along the length direction of the cavity C, the notch forming portion 140 may function as a cross-coupling bar for achieving coupling via at least one or more resonators.

[0112] Assume, refer to Figure 7, the C-notch portion 143 can start from a position relatively close to the resonator 170② on the input initial end side, extend across the adjacent resonator 170③ towards the position relatively close to the resonator 170④ on the output initial end side, thereby performing the function of cross-coupling the second resonator 170② and the fourth resonator 170④.

[0113] Similarly, the L-notch portion 141 can start from a position relatively close to the resonator 170⑤ on the input initial end side, extend across the adjacent resonator 170⑥ towards the position relatively close to the resonator 170⑦ on the output initial end side, thereby performing the function of cross-coupling the fifth resonator 170⑤ and the seventh resonator 170⑦.

[0114] In the structure of the filter 100A for a communication device according to an embodiment of the present invention, the notch forming portion 140 embodied as the first embodiment is as Figure 7 and Figure 8 shown, the L-notch portion 141 forms a stacked layer different from the stacked layer formed by the plurality of resonators 170 in the thickness direction of the cavity C, and forms a closed loop extending from one side in the width direction of the cavity C to the other side in the width direction. The C-notch portion 143 can be arranged in such a way as to form a stacked layer different from the stacked layer formed by the plurality of resonators 170 in the thickness direction of the cavity C, extend from one side in the width direction of the cavity C to the other side in the width direction, and be disposed adjacent to one of the resonant ends 173 of the plurality of resonators 170 in an adjacent manner.

[0115] Among them, preferably, the extending front end of the L-notch portion 141 forms a closed loop as much as possible within the magnetic field portion region, and preferably, the front end of the C-notch portion is adjacent to the resonant end 173 of the resonator to be coupled (assuming, the fourth resonator 170④).

[0116] Referring to the attached Figure 9 and Figure 10 A simple explanation of the principle of forming notches at the left and right ends of the passband based on the notch forming portion 140 embodied as the first embodiment is as follows.

[0117] If a signal is input from the input port portion 175A on one side of the cavity C, in each of the plurality of resonators 170, magnetic field coupling (L-Coupling) is dominant in the body portion 171 up to the resonant end 173 portion as its front end, and electric field coupling (C-Coupling) is dominant at the resonant end 173 portion, and both coupling characteristics exist simultaneously.

[0118] Further, when adjacent coupling occurs between each resonance element (i.e., the input port portion 175A, the output port portion 175B, and the plurality of resonators 170), the coupling property can be determined by additionally providing a notch structure (notch forming portion 140) in the cavity C. Accordingly, each structure of the notch forming portion 140 can also be defined.

[0119] More specifically, as Figure 9 and Figure 10 shown, adjacent coupling can be achieved between the second resonator 170② and the third resonator 170③, and between the third resonator 170③ and the fourth resonator 170④. And in general, magnetic field coupling predominates between the plurality of resonators 170, and inductive coupling can be achieved as can be seen from the circuit diagram of Figure 9 .

[0120] Meanwhile, the second resonator 170② and the fourth resonator 170④ achieve cross-coupling by means of the C-notch portion 143. In this case, electric field coupling predominates due to the extended front end of the C-notch portion 143. Therefore, it can be seen that capacitive coupling is achieved.

[0121] On the other hand, as Figure 9 and Figure 10 shown, adjacent coupling is also achieved between the fifth resonator 170⑤ and the sixth resonator 170⑥, and between the sixth resonator 170⑥ and the seventh resonator 170⑦, and inductive coupling is achieved. The fifth resonator 170⑤ and the seventh resonator 170⑦ achieve cross-coupling by means of the L-notch portion 141. In this case, it can be seen that the closed loop of the L-notch portion 141 is adjacent to the magnetic field portion where magnetic field coupling predominates, and inductive coupling is achieved at this point.

[0122] Therefore, as Figure 10 shown, when the notch forming portion 140 embodied as the first embodiment is used, a C-notch (left end) and an L-notch (right end) are respectively formed at the left end and the right end of the path band, and the designer can ensure the required frequency characteristics.

[0123] On the other hand, in the structure of the filter 100A for a communication device according to an embodiment of the present invention, the notch forming portion 140 embodied as the second embodiment is as Figure 11 and Figure 12 shown. The L-notch portion 141 and the C-notch portion 143 can be defined by one of the L-notch portion 141 and the C-notch portion 143 according to the properties of the relatively strong electric field portion and magnetic field portion expressed by adjacent coupling or cross-coupling among the plurality of resonators 170.

[0124] That is, in the notch forming section 140 embodied as the second embodiment, the C-notch section 143 can be the same as that in the first embodiment, which is a structure for implementing cross-coupling between the second resonator 170② and the fourth resonator 170④. However, different from the notch forming section 140 of the first embodiment, its shape can form a closed loop within the magnetic field section in the same way as the L-notch section 141, and there are differences in this regard.

[0125] Even so, in the notch forming section 140 embodied as the second embodiment, the C-notch section 143 is as Figures 11 to 14 shown, the separation distance L2 between the resonant ends 173 of the adjacent-coupled third resonator 170③ and fourth resonator 170④ is closer than the separation distance L1 between the resonant ends 173 of other multiple resonators (assuming the second resonator 170② and the third resonator 170③). In this regard, a C-notch based on capacitive coupling is formed at the left end of the path band. In this case, the notch forming section 140 for cross-coupling the second resonator 170② and the fourth resonator 170④ can be defined by the C-notch section 143.

[0126] Similarly, in the L-notch section 141 in the notch forming section 140 embodied as the second embodiment, compared with the capacitive couplings (electric field couplings) between the adjacent-coupled fifth resonator 170⑤ and sixth resonator 170⑥ and between the sixth resonator 170⑥ and seventh resonator 170⑦, the inductive coupling (magnetic field coupling) is more prominent. In this regard, an L-notch based on inductive coupling is formed at the right end of the path band. In this case, the notch forming section 140 for cross-coupling the fifth resonator 170⑤ and the seventh resonator 170⑦ can be defined by the L-notch section 141.

[0127] However, the definition methods of the above-mentioned L-notch section 141 and C-notch section 143 are limited to the case where each notch forming section 140 is respectively provided in the range of multiple resonators 170 (assuming other ranges in the length direction of the cavity C).

[0128] This is as Figures 15 to 18 shown. When the L-notch section 141 and the C-notch section 143 are set as a single structure in the same range in the length direction of the cavity C, it can be defined as a composite structure that simultaneously has the functions of the L-notch section 141 and the C-notch section 143 according to the properties based on adjacent coupling and the properties based on cross-coupling among multiple resonators 170.

[0129] More specifically, referring to Figure 15 and Figure 16The notch forming portion 140 starts from an adjacent portion of the second resonator 170② among the multiple resonators 170, and extends to an adjacent portion of the fifth resonator 170⑤ through the third resonator 170③ and the fourth resonator 170④ to form a closed loop, thereby performing the function of cross-coupling the second resonator 170② and the fifth resonator 170⑤.

[0130] In this case, the notch forming portion 140 realizes cross coupling via the even-numbered resonators 170, and in this regard, a function as inductive coupling is performed, and a spacing distance L2 between each resonance end 173 of the third resonator 170③ and the fourth resonator 170④ that realize adjacent coupling within the range of the notch forming portion 140 is formed closer than a spacing distance L1 between other multiple resonators, so that electric field coupling (electric field coupling) is dominant, thereby performing a function as capacitive coupling. In this regard, preferably, the notch forming portion 140 is defined not only by the L-notch portion 141, but also by a composite structure including the C-notch portion 143.

[0131] According to the notch forming portion 140 embodied in the third embodiment constructed in the manner as described above, Figure 18 As shown, a C-notch and an L-notch are formed at the left and right ends of the path strip, respectively, thereby expressing the frequency characteristics required by the designer.

[0132] Furthermore, in the communication device filter 100D according to an embodiment of the present invention, Figures 19 to 21 The notch forming portion 140 embodied in the fourth embodiment shown discloses the following notch forming principle.

[0133] That is, when assuming that the input port portion 175A and the output port portion 175B can be included as coupled resonant elements, the C-notch portion 143 can branch from the input port portion 175A and extend in a manner of separating the one side end resonator (i.e., the first resonator 170①) from the resonant end 173 of the resonator adjacent to it (i.e., the second resonator 170②).

[0134] Also, under the same assumption, the L-notch portion 141 may branch from the output port portion 175B and be connected to the resonator adjacent thereto (ie, the sixth resonator 170⑥) via the other side end resonator (ie, the seventh resonator 170⑦).

[0135] Among them, if the signal is input through the input port portion 175A, the C-notch portion 143 realizes capacitive coupling with the second resonator 170① and 170② through the first resonator 170① at the starting point of the signal input step, and when the signal is output through the output port portion 175B, the L-notch portion 141 realizes inductive coupling from the sixth resonator 170⑥ to the output port portion 175B through the seventh resonator 170⑦ at the end point of the signal output step.

[0136] In this case, the front end of the C-notch portion 143 may extend in the thickness direction to form a stacked layer different from the second resonator 170②, and may be configured not to be directly connected to the second resonator 170②.

[0137] Furthermore, preferably, the starting end of the L-notch portion 141 is configured to be directly connected to the sixth resonator 170⑥, and a window wall 145 that performs a function similar to that of a partition (Wall) of a common cavity filter may be provided between the sixth resonator 170⑥ and the seventh resonator 170⑦.

[0138] The window wall 145 can extend in the thickness direction through the mutually separated portions between the sixth resonator 170⑥ and the seventh resonator 170⑦, and at one side end of the cavity C, the front end in the width direction can extend to a portion of the position that limits the magnetic field coupling between the sixth resonator 170⑥ and the seventh resonator 170⑦.

[0139] According to the notch forming portion 140 embodied in the fourth embodiment as described above, Figure 21 As shown, it can be confirmed that a C-notch and an L-notch are formed at the left end and the right end of the path belt, respectively.

[0140] As described above, in the filter 100, 100A to 100D for communication equipment in one embodiment of the present invention, the cavity C is formed by folding (folding in half) the base material plate 105, providing the advantage of utilizing a simpler and more useful notch forming portion 140 inside the ultra-thin filter body with a small thickness direction to ensure the frequency characteristics required by the designer.

[0141] Although all the structural elements constituting the embodiment of the present invention are described as being combined into one, the present invention is not limited to such an embodiment. As long as it is within the scope of the purpose of the present invention, all the structural elements can be selectively combined into one according to the embodiment to operate.

[0142] The above description is only intended to illustrate the technical concept of the present invention in an illustrative manner, and a person skilled in the art in the technical field to which the present invention belongs can implement various modifications and variations without departing from the essential characteristics of the present invention.

[0143] Industrial Applicability

[0144] The present invention provides a filter for a communication device that can form a cavity by folding, and has a notch forming portion with a convenient and simple shape constructed inside and slightly smaller in size in the thickness direction, thereby ensuring various frequency characteristics, and thus facilitating the formation of design notches on both sides of a passband.

Claims

1. A filter for a communication device, characterized in that, Comprising: A base plate, which forms a hexahedral cavity with a thickness in the front-back direction at least smaller than the width in the left-right direction and with the up-down direction as the length direction when the radiation direction of the antenna element is defined as the front-back direction; A plurality of resonators, which form the same stacked layer with respect to the front-back direction (thickness direction) of the cavity; And An input port part and an output port part, wherein the input port part inputs a specified signal to the resonator at one end closest to the length direction of the cavity among the plurality of resonators, and the output port part outputs a specified signal from the resonator at the other end closest to the length direction of the cavity among the plurality of resonators, The filter for a communication device includes a notch forming part, which is disposed in the cavity and is arranged in a manner closer than the separation distance between the parts where magnetic field coupling is dominant or the parts where electric field coupling is dominant among the resonant elements including the input port part, the output port part, and the plurality of resonators sequentially selected along the length direction.

2. The filter for a communication device according to claim 1, wherein Among the plurality of resonators excluding the input port part and the output port part in the resonant elements, resonant ends serving as the parts where electric field coupling is dominant (hereinafter referred to as "electric field parts") are respectively formed in a divided manner at the front ends corresponding to the other ends in the width direction as the left-right direction. The part where electric field coupling is dominant is a part with a larger size in the length direction than the other part where magnetic field coupling is dominant (hereinafter referred to as "magnetic field part").

3. The filter for a communication device according to claim 2, characterized in that, The notch forming part includes: An L-notch part, which is adjacent in a manner that only affects the magnetic field part entirely; and A C-notch part, which is adjacent in a manner that a part affects the electric field part.

4. The filter for a communication device according to claim 3, wherein Among the plurality of resonators arranged sequentially along the length direction, the L-notch part and the C-notch part have the function of cross-coupling rods that achieve coupling with at least one or two or more resonators in between.

5. The filter for a communication device according to claim 3, wherein The L-notch part and the C-notch part are disposed in the cavity in a manner that forms the same stacked layer toward the thickness direction and in a manner that forms a different stacked layer from the plurality of resonators.

6. The filter for a communication device according to claim 5, wherein The L-notch part forms a closed loop extending from one side in the width direction of the cavity toward the other side in the width direction.

7. The filter for a communication device according to claim 5, wherein The C-notch part extends from one side in the width direction of the cavity toward the other side in the width direction and is disposed adjacent to one of the resonant ends of the plurality of resonators.

8. The filter for a communication device according to claim 5, wherein As for the L-notch portion, among at least three adjacent resonant elements selected in sequence along the length direction for multipath coupling, they are arranged in a manner relatively closer than the spacing distance between the electric field portions of each adjacent resonant element, thereby forming a prescribed notch at the right end of the path band to limit the region of the filtering frequency.

9. The communication device filter according to claim 5, characterized in that: As for the C-notch portion, among at least three adjacent resonant elements selected in sequence along the length direction for multi-path coupling, they are arranged in a manner that is relatively closer than the spacing distance between the magnetic field portions of each adjacent resonant element, thereby forming a prescribed notch at the left end of the path band to limit the area of ​​the filtering frequency.

10. The communication device filter according to claim 5, characterized in that: The L-notch portion and the C-notch portion are defined by one of the L-notch portion and the C-notch portion according to properties of the electric field portion and the magnetic field portion expressed relatively strongly by adjacent coupling or the cross coupling in the plurality of resonators.

11. The communication device filter according to claim 10, characterized in that: When the L-notch portion and the C-notch portion are respectively arranged in different ranges in the length direction of the cavity, the properties of the electric field portion and the magnetic field portion in the plurality of resonators are defined by one of the L-notch portion and the C-notch portion.

12. The communication device filter according to claim 5, characterized in that: When the L-notch portion and the C-notch portion are arranged in the same range in the length direction of the cavity in a single structure, the composite structure having the functions of the L-notch portion and the C-notch portion is defined according to the properties based on adjacent coupling and the properties based on cross coupling in the multiple resonators.

13. The communication device filter according to claim 5, characterized in that: When the input port and the output port are coupled resonant elements, The C-notch portion is branched from the input port portion and extends toward a resonance end of a resonator adjacent to the input port portion via the one-side end resonator.

14. The communication device filter according to claim 5, characterized in that: When the input port and the output port are coupled resonant elements, The L-notch portion branches from the output port portion and is connected to a resonator adjacent thereto via the other side end resonator.

15. The communication device filter according to claim 1, characterized in that: The cavity is formed into a single mother material plate by folding.

16. The communication device filter according to claim 15, characterized in that: The notch forming portion is separately manufactured in a plate form and is formed to correspond to the structure of the mother plate or is combined with the inside of the cavity.

17. The communication device filter according to claim 15, characterized in that: The notch forming portion is integrally provided on the base plate, and is provided in a plate form that is located inside the cavity when the folding is performed.

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