WO2014047820A1

WO2014047820A1 - Cavity filter

Info

Publication number: WO2014047820A1
Application number: PCT/CN2012/082081
Authority: WO
Inventors: 郭玲; 胡凯; 石晓明; 邹红; 周义兴
Original assignee: 华为技术有限公司
Priority date: 2012-09-26
Filing date: 2012-09-26
Publication date: 2014-04-03
Also published as: CN103201897A; CN103201897B

Abstract

A cavity filter is provided in the embodiments of the invention, relating to the field of communication, with the function of simplifying the assembling techniques and enhancing the reuse rate of moulds. The cavity filter includes the following parts: a cavity, including at least two resonant elements, each resonant element including a resonance single cavity and a resonator; a cover plate; through-holes set in the cover plate and led to the cavity; a coupling unit, two protruding ends of the coupling structure of whom extend into the two resonant elements with preset coupling relations in the cavity through the though-hole, to implement the coupling relations of the two resonant elements with preset coupling relations, wherein the central connecting line of the two protruding ends of the coupling structure is parallel to the plane containing the axis of the resonators of the two resonant elements, and the coupling structure is a capacitive coupling structure or an inductive coupling structure. The cavity filter provided in the embodiments of the invention is used for band-pass filtering in wireless communication.

Description

Cavity filter

The present invention relates to the field of communications, and in particular, to a cavity filter.

Background technique

At present, the cavity filter has better frequency-selective filtering in circuit and electronic high-frequency systems, and can suppress unwanted signals and noise outside the band, and has the advantages of low loss and high power, so in aviation, aerospace, communication. Widely used in electronic countermeasures, broadcast television and various electronic test equipment. The traditional cavity filter is realized by assembly, and its bandwidth and performance optimization are realized by the coupling between the resonators. The coupling is mainly realized by increasing the size of the window between the resonators and increasing the metal coupling structure between the tuning mast and the window. However, due to the different bandwidth and performance of different cavity filters, the window size between the resonators and the position of the coupling members in the middle of the cavity are different, resulting in a complicated assembly process of the cavity filter and a low mold multiplexing rate. Summary of the invention

Embodiments of the present invention provide a cavity filter that simplifies the assembly process and increases the mold reuse rate.

In order to achieve the above objectives, embodiments of the present invention adopt the following technical solutions:

In one aspect, a cavity filter is provided, comprising:

a cavity, the cavity comprising: at least two resonating units, the resonating unit comprising: a resonant single cavity and a resonator;

Cover plate

a through hole disposed on the cover plate and communicating with the cavity;

a coupling unit, wherein the two protruding ends of the coupling structure of the coupling unit respectively extend into the two resonance units of the cavity in a preset coupling relationship for implementing the preset Coupling relationship of two resonant units of a coupling relationship,

Wherein the center line of the two protruding ends of the coupling structure and the two resonances The plane of the axis of the resonator of the unit is parallel, and the coupling structure is: a capacitive coupling structure or an inductive coupling structure.

The resonant unit is a separate component;

The inner side of the cover plate is provided with a positioning groove arranged in a predetermined top structure, and the resonance unit is fixed on the cover plate by coupling the resonant single cavity opening face and the positioning groove.

The cavity filter further includes:

The capacitive coupling structure, the capacitive coupling structure is not in contact with the cover plate and the resonant unit;

a support member for fixing the capacitive coupling structure to the cover plate; a shielding unit for preventing leakage of an electromagnetic field of the cavity filter.

The cover plate is a die-casting member, and the cover plate is provided with a fixing groove for fixing the support member, and the fixing groove is in communication with the through hole;

The shielding unit is a first shielding cover, and the first shielding cover covers the mounting groove of the fixing slot.

The cover plate is a sheet metal member, and the support member is fixed to the outside of the cover plate; the shielding unit is a shield cover, and the shield cover buckle is disposed above the support member and the through hole.

The coupling unit includes:

a second shielding cover, the second shielding cover is fastened on the through hole for preventing leakage of an electromagnetic field of the cavity filter;

The inductive coupling structure is connected to the second shielding cover in an inverted "concave" shape, and the two protruding ends of the inductive coupling structure are short-circuited.

The cavity filter further includes:

Located on the cover plate, extending through the cover plate to a tuning screw in the resonant single cavity, the axis of the tuning screw being collinear with the resonator axis for debugging the passband frequency;

Located outside the cover plate, a tuning nut threaded on the tuning screw for locking the tuning mast. The resonant unit is an integral part formed by stamping.

The resonant unit is a split type component;

The resonant single cavity is formed by stamping, and the bottom is provided with a positioning structure;

The resonator is formed by stamping;

The resonator is fixed to the positioning structure of the resonant single cavity to form the resonant unit.

When the length of the first protruding end and the second protruding end of the capacitive coupling structure increases or the distance between the first protruding end and the second protruding end increases, the presence preset The capacitive coupling of the two resonant units of the coupling relationship is enhanced;

When the length of each convex end of the inductive coupling structure is increased or the width is widened, the inductive coupling of the two resonance units having the predetermined coupling relationship is enhanced.

An embodiment of the present invention provides a cavity filter, including: a cavity, the cavity includes: at least two resonating units, the resonating unit includes: a resonant single cavity and a resonator; a cover; disposed on the cover a through hole communicating with the cavity; a coupling unit, wherein two protruding ends of the coupling structure in the coupling unit respectively protrude into the cavity through the through hole and have two preset coupling relationships a coupling relationship between the two resonating units in which the predetermined coupling relationship exists, wherein a center line connecting the two protruding ends of the coupling structure and a resonator of the two resonating units The plane of the axis is parallel, and the coupling structure is: a capacitive coupling structure or an inductive coupling structure. In this way, when installing, the cavity and the cover are assembled, the assembly process is simple, and the coupling unit is convenient for replacement and adjustment, and the process of realizing different bandwidths does not need to destroy the complete structure of the resonant unit, and the setting of the resonant unit of the cavity In the same way, the molds of the cavity filters having the same shape requirements can be multiplexed, thereby simplifying the assembly process and increasing the mold reuse rate. DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the description of the prior art will be briefly described below. Obviously, the drawings in the following description are only It is a certain embodiment of the present invention, and other drawings can be obtained from those skilled in the art without any creative work. 1 is a schematic structural diagram of a cavity filter provided by the prior art; FIG. 2 is a schematic structural diagram of a cavity filter according to an embodiment of the present invention; FIG. 3 is another cavity filtering provided by an embodiment of the present invention. FIG. 4 is a schematic structural diagram of a resonant unit according to an embodiment of the present invention;

5 is a cross-sectional view of the cavity filter of FIG. 3 according to an embodiment of the present invention; FIG. 6 is a cross-sectional view of another cavity filter according to an embodiment of the present invention; Schematic diagram of the coupling unit structure;

FIG. 8 is a schematic diagram of a combination of a coupling unit and a resonant unit of a cavity filter according to an embodiment of the present invention.

detailed description

The technical solutions in the embodiments of the present invention are clearly and completely described in the following with reference to the accompanying drawings in the embodiments of the present invention. It is obvious that the described embodiments are only a part of the embodiments of the present invention, but not all embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention without creative efforts are within the scope of the present invention.

The cavity filter 10 of the prior art, as shown in FIG. 1, includes: a cavity 101, a cover plate 102, a coupling structure 103, a support member 104, a resonator 105, a fixing screw 106, a tuning mast 107 and a fixing nut. 108 and so on. The cavity 101 is formed into an integrated device by machine or die casting, and the cover plate 102 is formed by die casting or using a forming plate machine. When assembling, the coupling structure 103 and the support member 104 are assembled into a component fixed inside the cavity 101, and then the resonator 105 is fixed to the center of the resonant single cavity 101 1 of the cavity 101 by a fixing screw 106 to constitute a resonance unit, and then The tuning mast 107 and the retaining nut 108 are secured to the cover plate 102, and the assembled cover assembly and cavity assembly are finally assembled by the set screws 106.

The embodiment of the present invention provides a cavity filter 20, as shown in FIG. 2, including: a cavity 201, the cavity 201 includes: at least two resonating units 201 1 , the resonating unit 201 1 includes: a resonance single The cavity 201 1a and the resonator 201 lb.

Cover plate 202.

A through hole 2021 is formed in the cover plate 202 to communicate with the cavity 201.

a coupling unit 203, the two protruding ends of the coupling structure in the coupling unit 203 pass The through holes 2021 respectively extend into two resonant units in the cavity in a predetermined coupling relationship, and are used to implement a coupling relationship between the two resonant units having a preset coupling relationship, wherein the coupling structure The center line of the two protruding ends is parallel to the plane of the axis of the resonator of the two resonant units, and the coupling structure is: a capacitive coupling structure 2031 or an inductive coupling structure 2032.

In this way, when installing, the cavity and the cover are assembled, the assembly process is simple, and the coupling unit is convenient for replacement and adjustment, and the process of realizing different bandwidths does not need to destroy the complete structure of the resonant unit, and the setting of the resonant unit of the cavity In the same way, the molds of the cavity filters having the same shape requirements can be multiplexed, thereby simplifying the assembly process and increasing the mold reuse rate.

The cavity 201 may be an integrated component. As shown in Fig. 2, the resonant unit 201 1 in the cavity 201 has the same structure and does not open the window.

In particular, the embodiment of the present invention further provides another cavity filter 30, as shown in FIG. 3, including: the resonating unit 301 is an independent component, and the resonating unit 301 includes: a resonant single cavity 3011 and a resonance The device 3012.

For example, the resonating unit 301 may be an integral part formed by stamping, machining, die casting, forging or injection molding as shown in FIG. 3, and the resonating unit 301 has a shape similar to a bowl-like structure, and the bowl bottom of the bowl-shaped structure is formed inward. The cylindrical shape 1HJ becomes a structure as shown in Fig. 5, and the axial section of the resonance unit 301 approximates an inverted "concave" shape. The resonator 3012 is a cavity surrounded by a plane parallel to the opening surface of the resonant unit 301 and a bowl-shaped structure in which the straight lines e and f are located in FIG. 5, that is, the resonator is formed by the convex shape in FIG. Since the electromagnetic field acts only on the surface of the resonator when the resonator is working, the skin depth of the electromagnetic field is different depending on the working frequency band of the filter, and generally has a skin depth of about several to ten μm, so when in resonance Reversely punching out the shape of the above resonator on a single cavity acts as a resonator to resonate the electromagnetic field on the surface of the resonator. Further, the resonant single cavity 301 1 is a portion of the bowl-shaped structure other than the cavity.

The resonant unit 301 can also be assembled by the resonant single cavity 3011 and the resonator 3012. As shown in FIG. 5, the resonant single cavity 3011 can be formed by stamping, and the bottom is provided with a positioning structure M, which can be a positioning groove. It is also possible to have a structure in which a positioning function can be realized, such as a boss structure, and the present invention is not limited thereto. Resonator 3012 can pass through Pressing, the resonator 3012 is a barrel structure, and the opening edge of the barrel structure is turned down, so that the frequency variation range of the cavity filter can be enlarged; the resonator 3012 is fixed to the resonance single by welding or riveting or the like. The resonance unit 301 is formed at the positioning structure M of the cavity 3011. In particular, the above-mentioned resonant single cavity 301 1 can also be formed by machining, die casting, forging or injection molding, and the present invention is only illustrative, and no limitation is imposed thereon. The assembled resonant unit 301 can be subjected to surface treatment, such as pickling, followed by silver or copper plating, thereby removing impurities on the surface of the resonant unit 301, improving the surface conductivity of the cavity filter 30, and simultaneously improving the cavity filter. 30 performance.

a cover plate 302 is disposed on the inner side of the cover plate 302 with a positioning slot 3021 arranged according to a preset topography. The resonating unit 301 is fixed to the cover plate by coupling the resonant single-cavity opening surface with the positioning slot. 302. It should be noted that the topology structure in the embodiment of the present invention represents a form in which each of the resonant units in the cavity filter are connected to each other, and the main topological structures are a bus topology, a star topology, a ring topology, and the like. The hybrid type, in practical applications, can be specifically set according to the performance requirements of the cavity filter.

The positioning groove 3021 may be a positioning groove or a structure capable of positioning, such as a boss structure. For example, a positioning groove having a preset topography may be machined or punched on the cover plate, and then positioned. The groove is filled with solder paste or other flux, and the corresponding resonance units are placed one by one in the positioning groove. After the tool is accurately positioned, the cover plate and the resonance unit are welded by a high-temperature reflow soldering method to form a body of the cavity filter. Specifically, in the embodiment of the invention, the side of the cover plate that is in contact with the resonant single-cavity opening surface is the inner side, and the non-contact side is the outer side.

In this way, since the resonant unit is independent, it is no longer an integral cavity composed of a resonant single cavity. The assembly of the resonant unit is fixed to the cover plate by coupling with the positioning groove one by one, and does not need to be integrally assembled with the cover plate. Compared with the prior art, the mold is no longer limited in terms of bandwidth, volume and topology, but the resonant unit is the main opening object, and the same frequency band products only need to be developed. Several reciprocating unit molds can cover most of the filter requirements. Even if the shape is slightly changed, the topology is changed, and the resonant unit mold can be reused, so the assembly process can be simplified and the mold reuse rate can be improved. Further, as shown in FIG. 3, the cavity filter 30 may further include: a through hole 3022 disposed on the cover plate 302 and communicating with the resonant single cavity 3012.

a coupling unit 303, wherein the two protruding ends of the coupling structure 303 1 of the coupling unit 303 respectively extend into the two resonance units in a preset coupling relationship through the through holes 3022 for realizing the two resonances a coupling relationship of the unit, wherein a center line connecting the two protruding ends of the coupling structure is parallel to a plane of an axis of the resonator of the two resonance units, and the coupling structure 303 1 is: a capacitive coupling structure 303 1 a or inductive coupling structure 303 1 b , therefore, the coupling unit 303 is also divided into a capacitive coupling unit (which may also be referred to as an electrical coupling unit) and an inductive coupling unit (which may also be referred to as a magnetic coupling unit). The coupling unit 303 can realize the capacitive coupling relationship and the inductive coupling relationship of the two resonance units having the preset coupling relationship described above.

As shown in FIG. 5 and FIG. 6 , when the coupling unit 303 is used to implement a capacitive coupling relationship between two resonant units, the coupling unit 303 may include: a capacitive coupling structure 303 1 a , the capacitive coupling structure and The cover plate and the resonating unit are not in contact; a support member 3032 for fixing the capacitive coupling structure to the cover plate, and the support member 3032 may be a PEI (Polyetherimide, polyetherimide) or the like. The insulating member 3030 can be supported by injection molding, and the support member 3032 can support the contact, and the capacitive coupling structure and the cavity cover can be prevented from contacting the capacitive coupling structure and the cavity cover. Insulation; shielding unit 3033 for preventing leakage of an electromagnetic field of the cavity filter. In particular, the capacitive coupling structure may include: a first protruding end X and a second protruding end Y, wherein the first protruding end X and the second protruding end Y are a single piece, and the first protruding end X. One end of the second protruding end Y is connected inside the support member 3032 to avoid contact with the cover 302 and the resonating unit 301, so that the supporting member 3032 supports the capacitive coupling structure 303 1 a and enables The capacitive coupling structure 303 1 a is insulated from the cover 302 and the resonating unit 301, and the first protruding end X, the other end _{2 of the} second protruding end Y, and the through hole 3022 respectively protrude into the pre-presence In the two resonance units of the coupling relationship.

As shown in FIG. 5, the cover plate 302 may be a die-casting die-casting piece. When the cover plate 302 is a die-casting part, the cover plate 302 is a thick cover plate. Due to the thick thickness, the cover plate 302 may be fixed. a fixing groove 3023 of the supporting member 3032, the fixing groove 3023 can be The fixing groove 3023 is in communication with the through hole 3022 by being formed by die casting or subsequent machining. In FIG. 5, the shielding unit 3033 is a first shielding cover, and the first shielding cover covers the mounting groove of the fixing groove 3023. The support member 3032 can be mounted at a specified position of the thick cover plate 302 by a fixing screw, usually on the barrier ribs 306 of two adjacent resonating units, and then the first protruding end X and the second protruding end of the capacitive coupling structure 3031a. The end Y is respectively penetrated into the two resonating units, and the capacitive coupling structure 3031a is mounted on the support member 3032 by a fixing screw. Two protruding positioning pins can be disposed on the supporting member 3032 to determine the first protruding end X and the first The installation position of the two protruding ends Y. On the cover plate formed by die-casting, since the thread can be set, the connection mode of each device is usually screw connection, which is convenient when assembling and disassembling the device.

As shown in FIG. 6 , the cover plate 302 can also be a sheet metal piece. When the cover plate 302 is a sheet metal piece, the support piece 3032 can be fixed to the outside of the cover plate 302 by screws, and is buckled on the sheet metal. The shielding unit 3033 is a shield cover, and the shield cover is placed above the support member 3032 and the through hole 3022 to avoid electromagnetic field leakage of the cavity filter.

As shown in FIG. 5, when the coupling unit 303 is used to implement an inductive coupling relationship between two resonant units, the coupling unit 303 includes:

a second shielding cover 3034, the second shielding cover 3034 is fastened on the through hole for preventing electromagnetic field leakage of the cavity filter; an inductive coupling structure 3031b, the inductive coupling structure 3031b and the first The two shielding covers 3034 are connected in an inverted "concave" shape, and the two protruding ends S and W of the inductive coupling structure 3031b are short-circuited. The inductive coupling structure 3031b and the second shielding cover 3034 can be seen from FIG. The section is a closed loop. During assembly, the inductive coupling structure 3031b and the second shielding cover 3034 may be connected by soldering, and then the side of the second shielding cover 3034 and the inductive coupling structure 3031b is connected to the cavity filter, and is fastened to the cover. The position corresponding to the hole.

Further, the cavity filter 30 may further include:

Located on the cover plate 302, extending through the cover plate 302 to the tuning screw 304 in the resonant single cavity 3011, the axis of the tuning screw 304 being collinear with the axis of the resonator 3012 for debugging the passband frequency; Located outside the cover 302, threaded to the tuning A tuning nut 305 on the screw 304, the tuning nut 305 is used to lock the tuning mast 304 so that it does not move axially. When the cover plate 302 is a die-casting member, as shown in FIG. 5, a circular groove or a square groove may be disposed on the cover plate 302 for tuning the positioning of the screw 304 and the tuning nut 305, and the tuning screw 304 is disposed from the circular groove. Or a threaded hole in the center of the square groove passes into the resonant single cavity 30 1 1 . The tuning screw 304 and the tuning nut 305 are placed in a circular groove or a square groove, so that the surface of the cover plate 302 has no protruding structural members, so that the outer shape of the cover plate 302 is flat and beautiful. As shown in FIG. 6, when the cover plate 302 is a sheet metal member, the tuning screw 304 can extend directly through the cover plate 302 into the resonant single cavity 30 1 1 . By adjusting the relative position of the screw and the resonator by twisting the tuning screw adjustment, the passband frequency of the cavity filter can be tuned, and the relative position of the tuning nut and the tuning screw can be adjusted to achieve the locking action. Specifically, when the tuning screw 304 is The depth of the inner side of the cover plate 302 is deepened, and the passband frequency of the cavity filter is lowered. When the depth of the tuning screw 304 inside the cover plate 302 becomes shallow, the pass band frequency of the cavity filter is increased.

In the prior art, the coupling relationship between the two cavities is usually realized by increasing the window size between the resonant cavities in the cavity and adding a metal coupling component between the tuning mast and the window in the middle of the window, in the embodiment of the present invention. The coupling relationship between the two cavities is realized by the coupling unit, the tuning screw and the tuning nut. Among them, the coupling unit plays an important role in realizing the coupling relationship between the two cavities. In the embodiment of the present invention, the structure and position of the respective resonating units can be changed, and only the coupling unit between the two cavities can be replaced to change the bandwidth of the cavity filter and the topology structure.

For example, FIG. 7-a is a perspective view and a side view of the coupling unit 303 as a capacitive coupling unit. In practical applications, the two protruding ends of the capacitive coupling structure 303 1 a and the inductive coupling structure 303 1 b are symmetric structures. Therefore, in the embodiment, the two convex end pairs of the capacitive coupling structure 303 1 a and the inductive coupling structure 303 1 b are referred to as an example. In the embodiment of the present invention, the capacitive coupling structure 303 1 a can be adjusted. The length h of the first protruding end and the second protruding end and the distance between the first protruding end and the second protruding end (which may also be referred to as a width) i can adjust the presence preset coupling The size of the capacitive coupling of the two resonant units of the relationship, having a length h of the first protruding end and the second protruding end increasing or a distance i of the first protruding end and the second protruding end increasing Large, cavity filter The bandwidth is increased and the corresponding capacitive coupling is enhanced. 7-b is a perspective view and a side view of the coupling unit 303 being an inductive coupling unit, and the two preset existence coupling states can be adjusted by adjusting the length j and the width k of each convex end of the inductive coupling structure 303 1b The magnitude of the inductive coupling of the resonant unit, specifically, as the length j of the convex end increases or the width k widens, the bandwidth of the cavity filter increases, and the corresponding inductive coupling is enhanced. When the structure of the coupling unit is fixed, the performance of the filter can be changed simply by changing the position of the coupling unit. For example, as shown in FIG. 8, the structure and position of the resonant units 1, 2, 3, and 4 are not changed, and the implementation of different filter performance can be achieved by changing or adjusting the positions of the shielding units 1, 2, 3, and 4. Figure 8 is only a schematic example of three examples, the actual adjustment method is not limited to this. In particular, by adjusting or replacing the shielding unit, the topology of the cavity filter can be changed without changing the layout of the cavity filter cavity. The cavity filter can have multiple frequency bands, such as 800MHZ, 1800M, 2600MHZ, etc. In the cavity filter manufacturing stage, different specifications of the resonant unit and the coupling unit can be developed for different frequency bands, according to the implementation, The topology of the cavity filter is assembled. When the resonant unit of the cavity filter is damaged or faulty, the resonant unit can be replaced. When the coupling relationship or topology of the cavity filter needs to be changed, the resonant unit can be replaced. Or changing the position of the resonant unit to adjust the coupling relationship or the topology structure, avoiding the situation that the mold and the filter product are not reusable after the topology structure is changed, so that the reconfigurability of the cavity filter is enhanced, and the cost is reduced. In particular, the performance of the filter can also be adjusted by adjusting the resonant single cavity and the resonator in the resonant unit. For example, the material of the resonant single cavity or resonator can be changed, and the size of the resonant single cavity or resonator can be changed, etc. It is to be understood that those skilled in the art are susceptible to variations and substitutions within the scope of the present invention.

In practical applications, a mounting groove for placing a shielding cover or a shielding shield may be disposed on the cover plate corresponding to a position where each two adjacent resonant units are in contact. When the cavity filter is assembled, the two cavities in the coupling relationship are connected by the corresponding resonating units. If there is no coupling relationship, the shielding cover or the shielding cover can be directly placed. In particular, it can also be fabricated on the cover plate. When setting the position of the mounting groove according to the preset top structure, on the cover, The position of the two resonance units that do not have a coupling relationship is not provided with the fitting groove. Thus, in mass production, the main processing needs to be the cover plate, the resonant single cavity and the resonator in the resonant unit, and the support member, the coupling structure and the shielding unit in the coupling unit can all adopt uniform normalized devices, and most of them It can be realized by automated tooling, which improves the efficiency of production and processing and reduces labor costs.

In particular, when the cover plate and the resonating unit are sheet metal parts formed by sheet metal stamping, the shielding cover or the shield cover, the fixing screw and the like on the cover plate can be integrated by high-temperature reflow soldering or the like after being fixed by all the tools. The assembly, cover and resonating unit are connected by welding or riveting, reducing the number of screw connections and thus reducing the weight of the cavity filter. At the same time, since both the cover plate and the resonance unit can be realized by stamping, the yield can be improved compared with the prior art.

It should be noted that the screw for fixing in the embodiment of the present invention may also be replaced by other similar mechanical parts, such as a bolt, a through hole, or a threaded hole. For the specific implementation, reference may be made to the prior art. Any changes or substitutions that are readily conceivable within the scope of the present invention are intended to be included within the scope of the present invention.

In the cavity filter provided by the embodiment of the invention, the resonance unit is independent, and the resonance unit is divided into an integral stamping method and a split stamping assembly mode, and the filter filter cover plate can be formed by a die-cast thick cover plate and punching. The thin cover plate is realized, wherein the thick cover plate can be connected by screws, and the stamped thin cover plates can all be connected by welding. The assembly mode and connection mode of the above resonance unit can be freely used according to specific requirements in practical applications. combination. According to the change of volume and performance, a suitable resonant unit can be selected and combined to realize the reconfigurable cavity filter.

In the several embodiments provided by the present application, it should be understood that the disclosed cavity filter can be implemented in other manners. For example, the device embodiments described above are merely illustrative. For example, the division of the structure is only a logical function division. In actual implementation, there may be another division manner, for example, multiple components may be combined or integrated. Go to another system, or some features can be ignored, or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection through some interface, device or unit, and may be electrical, Mechanical or other form.

The structures described as separate components may or may not be physically separated, and the components displayed as structures may or may not be physically structured, and may be located in one place or distributed over a plurality of network structures. Some or all of the structures may be selected according to actual needs to achieve the objectives of the embodiment of the present embodiment. The above is only the specific embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily think of changes or substitutions within the technical scope of the present invention. It should be covered by the scope of the present invention. Therefore, the scope of the invention should be determined by the scope of the claims.

Claims

Claim

A cavity filter, comprising:

Cover plate

a through hole disposed on the cover plate and communicating with the cavity;

The center line of the two protruding ends of the coupling structure is parallel to the plane of the axis of the resonators of the two resonant units, and the coupling structure is: a capacitive coupling structure or an inductive coupling structure.

2. The cavity filter according to claim 1, wherein

The resonant unit is a separate component;

The inner side of the cover plate is provided with a positioning groove arranged in a predetermined top structure, and the resonance unit is fixed on the cover plate by coupling the resonant single-cavity opening surface and the positioning groove.

The cavity filter according to claim 1 or 2, wherein the coupling unit comprises:

a support member for fixing the capacitive coupling structure to the cover plate;

A shielding unit for preventing leakage of an electromagnetic field of the cavity filter.

4. The cavity filter according to claim 3, wherein

The cover plate is a die-casting member, and the cover plate is provided with a fixing groove for fixing the support member, and the fixing groove is communicated with the through hole;

5. The cavity filter of claim 3, wherein

The cover plate is a sheet metal member, and the support member is fixed to an outer side of the cover plate;

The shielding unit is a shielding cover, and the shielding cover buckle is disposed above the support member and the through hole.

The cavity filter according to claim 1 or 2, wherein the coupling unit comprises: a second shielding cover, the second shielding cover is fastened on the through hole for preventing leakage of an electromagnetic field of the cavity filter;

The cavity filter according to any one of claims 1 to 6, wherein the cavity filter further comprises:

Located on the cover plate, extending through the cover plate to the tuning screw in the resonant single cavity, the axis of the tuning screw is collinear with the resonator axis, and is used for debugging the passband frequency;

Located outside the cover plate, a tuning nut threaded on the tuning screw for locking the tuning mast.

A cavity filter according to any one of claims 1 to 7, which is characterized in that

The resonant unit is an integral part formed by stamping.

9. A cavity filter according to any one of claims 1 to 7, characterized in that

The resonant unit is a split type component;

The resonator is formed by stamping;

10. A cavity filter according to any one of claims 1 to 9, characterized in that