A three-dimensional micro-metal structure hybrid resonator filter

Abstract

The present invention belongs to the field of filter technology and specifically discloses a three-dimensional micro-metal structure hybrid resonator filter, comprising a metal housing; a first cavity resonator, a second cavity resonator, a third cavity resonator, and a fourth cavity resonator arranged in a ring within the housing, with a transmission line resonator located between the second and third cavity resonators; an output coupling structure and an input coupling structure are micro-coaxial line-board-level welded adapter structures and are respectively arranged on either side of the housing, with the input coupling structure connected to the first cavity resonator and the output coupling structure connected to the fourth cavity resonator; after the input coupling structure feeds a signal into the first cavity resonator of the filter, the fourth cavity resonator feeds the signal into the output coupling structure. The filter of the present invention is small in size and has the advantages of low loss, high selectivity, and a wide range of applications.

Description

Technical Field

[0001] The invention belongs to the technical field of filters, and in particular relates to a three-dimensional micro-metal structure hybrid resonator filter. Background Art

[0002] Filters are a crucial component of communication systems, their primary function being to extract signals at frequencies of interest and suppress other unwanted signals. Common types of resonators used in filter design include cavity resonators and transmission line resonators. Generally speaking, cavity filters offer a high quality factor and high power handling capacity, significantly improving the filter's frequency band selectivity and achieving lower losses. However, their larger size hinders miniaturization and high integration. Transmission line resonators have a lower quality factor than cavity resonators, but offer the advantage of miniaturization.

[0003] In specific designs, cavity resonators typically use full substrate integrated waveguide resonators, half-mode or quarter-mode substrate integrated waveguide resonators, while transmission line resonators generally use open-ring resonators or microstrip resonators. However, due to the large cavity size of full substrate integrated waveguide resonators, and the large radiation loss caused by the open structure of half-mode and quarter-mode substrate integrated waveguide resonators, the insertion loss of the filter at higher frequencies is further deteriorated. Although microstrip resonators are easy to miniaturize, they still have the problem of high dielectric loss and radiation loss at higher frequencies.

[0004] In order to maximize the advantages of various resonator structures while avoiding their disadvantages, hybrid resonator filters formed by composite designs using multiple resonators have emerged. However, since the design of existing hybrid resonator filters is mostly based on dielectric substrates, this will limit the hybrid resonator filters to problems such as dielectric loss and radiation loss, resulting in high losses when used at higher frequencies and a narrow application range. Summary of the Invention

[0005] The purpose of the present invention is to provide a three-dimensional micro-metal structure hybrid resonator filter with the advantages of low loss and high selectivity. It significantly reduces the size of the filter and enables the filter to have board-level interconnection integration capabilities, thereby solving the technical problems of existing three-dimensional micro-metal structure hybrid resonator filters such as high loss when used at higher frequencies and a narrow application range.

[0006] To achieve the above objectives, the present invention provides a three-dimensional micro-metal structure hybrid resonator filter, the specific technical solution of which is as follows:

[0007] A three-dimensional micro-metal structure hybrid resonator filter, comprising:

[0008] Metal housing;

[0009] The first cavity resonator, the second cavity resonator, the third cavity resonator and the fourth cavity resonator are located in the shell and arranged in a ring shape. The coupling between the first cavity resonator and the second cavity resonator, between the third cavity resonator and the fourth cavity resonator, between the second cavity resonator and the transmission line resonator, and between the transmission line resonator and the third cavity resonator is magnetic coupling, and the coupling between the second cavity resonator and the third cavity resonator is electrical coupling.

[0010] a transmission line resonator located between the second cavity resonator and the third cavity resonator;

[0011] The output coupling structure and the input coupling structure are both micro-coaxial line-board-level welding transition structures, respectively arranged on both sides of the shell, wherein the input coupling structure is connected to the first cavity resonator, and the output coupling structure is connected to the fourth cavity resonator; the input coupling structure feeds the signal into the first cavity resonator of the filter, and the signal is fed into the output coupling structure by the fourth cavity resonator.

[0012] Preferably, the first cavity resonator, the second cavity resonator, the third cavity resonator and the fourth cavity resonator have the same structure, the first cavity resonator includes a first cavity opened inside the shell, a first metal column is provided at the center position of the first cavity, one end of the first metal column is connected to the bottom surface of the first cavity, and there is a first gap between the other end and the top surface of the first cavity.

[0013] Preferably, the transmission line resonator includes a fifth cavity and a first metal core located inside the fifth cavity, the first metal core includes a first plate, a second plate, a third plate, a fourth plate and a fifth plate connected end to end in sequence, wherein the second plate, the third plate and the fourth plate are located on a first plane, the second plate and the fourth plate are parallel, the third plate and the fourth plate are perpendicular, the first plate and the fifth plate are located on a second plane, the second plane is perpendicular to the first plane, and the first plate and the fifth plate are both in contact with the top of the inner wall of the shell to form a short-circuit structure.

[0014] Preferably, the structure for realizing the magnetic coupling includes a coupling window structure on the side wall between the first cavity resonator and the second cavity resonator, between the third cavity resonator and the fourth cavity resonator, between the second cavity resonator and the transmission line resonator, and between the transmission line resonator and the third cavity resonator, and a release hole structure located on the shell.

[0015] Preferably, the structure for realizing the electrical coupling includes a third coupling window and an umbrella-shaped pin, wherein the third coupling window is opened on the side wall between the second cavity resonator and the third cavity resonator, and the umbrella-shaped pin is located in the middle of the third coupling window, and is used to generate a transmission zero point in the high-frequency stop band while providing electrical coupling.

[0016] Preferably, the umbrella-shaped pin includes a metal plate and a metal column, one end of the metal column is fixed to the bottom of the cavity of the shell, and the other end of the metal column is fixed to the metal plate.

[0017] Preferably, the output coupling structure has the same structure as the input coupling structure, and the input coupling structure includes a third release hole and a second metal core, one end of the second metal core is located in the first cavity resonator, and a first opening is provided on the bottom surface of the shell, and the other end of the second metal core is located in the first opening. An air gap structure is formed between the four sides of the second metal core and the inner wall of the first opening, and the second metal core and the first opening constitute an interface interconnected with external components, which is used to realize the transmission of signals from the second metal core to the first cavity resonator. The third release hole is provided on the bottom surface of the shell, located on the lower side of the second metal core, and is used to complete the field conversion from the second metal core to the first cavity resonator, and to excite the resonant mode of the first cavity resonator to realize the excitation of the filter.

[0018] Preferably, the second metal inner core includes a sixth plate, a seventh plate and an eighth plate connected in sequence, the sixth plate and the eighth plate are parallel, the sixth plate and the seventh plate are perpendicular, the end of the sixth plate away from the seventh plate is fixed to the top of the cavity of the shell, the end of the eighth plate away from the seventh plate is arranged in the first through opening and the end face of the eighth plate is flush with the surface of the shell.

[0019] Preferably, the seventh plate body is a stepped structure.

[0020] Compared with the prior art, the present invention provides a three-dimensional micro-metal structure hybrid resonator filter that abandons the traditional dielectric substrate structure, avoids the influence of radiation loss and dielectric loss, and reduces the insertion loss of the hybrid resonator filter. It has the advantages of high frequency, low loss, and high selectivity that traditional dielectric plate circuits do not have. The entire filter structure adopts a first cavity resonator, a second cavity resonator, a third cavity resonator, and a fourth cavity resonator arranged in a ring. The transmission line resonator is arranged between the second cavity resonator and the third cavity resonator. The signal is fed into the first cavity resonator of the filter through an input coupling structure and fed into the output coupling structure from the fourth cavity resonator to form a signal path. This structure enables the filter to have the advantages of low loss and high selectivity when used at higher frequencies. In addition, because the input coupling structure and the output coupling structure are micro-coaxial line-to-board-level welding transition structures, they can effectively feed the filter without occupying too much space, significantly reducing the size of the filter, facilitating board-level integration of the filter with other devices, and broadening the application range of the filter. The filter is highly practical and worthy of promotion. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a top view frame diagram of the present invention.

[0022] Figure 2 It is a side view block diagram of the present invention.

[0023] Figure 3 It is a top perspective view of the present invention.

[0024] Figure 4 It is a bottom plan view of the present invention.

[0025] Figure 5 It is a top cross-sectional view of the present invention.

[0026] Figure 6 A side cross-section of the present invention Figure 1 .

[0027] Figure 7 A side cross-section of the present invention Figure 2 .

[0028] Figure 8 It is a bottom top cross-sectional view of the present invention.

[0029] Figure 9 It is a side view of the present invention.

[0030] Figure 10 It is a cross-sectional view of the present invention.

[0031] Figure 11 This is a coupling path diagram of the present invention.

[0032] Figure 12This is a diagram of the S-parameter simulation results of the present invention. DETAILED DESCRIPTION

[0033] The current design of hybrid resonator filters is mostly based on dielectric substrates, which limits the hybrid resonator filters to dielectric loss and radiation loss. This results in high losses when used at higher frequencies and a narrow application range.

[0034] In response to the technical problems of high loss and narrow application range of current hybrid resonator filters when used at higher frequencies, the present invention provides a new three-dimensional micro-metal structure hybrid resonator filter, which abandons the traditional dielectric substrate structure, avoids the influence of radiation loss and dielectric loss, reduces the insertion loss of the hybrid resonator filter, and has the operating advantages of high frequency, low loss and high selectivity that traditional dielectric plate circuits do not have.

[0035] The following will be combined with the Figure 1 To the attached Figure 12 , clearly and comprehensively describe the technical solutions in the present invention.

[0036] It should be further explained that, in the description of the embodiments of the present invention, unless otherwise specified, “ / ” means or. For example, A / B can mean A or B. The “and / or” in the text is merely a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present invention, “multiple” refers to two or more than two.

[0037] In addition, it should be understood that the terms "center", "up", "down", "front", "back", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0038] The terms "first," "second," "third," and "fourth" below are used for descriptive purposes only and should not be understood to imply or suggest relative importance or implicitly indicate the number of the technical features indicated. Thus, features qualified as "first," "second," "third," and "fourth" may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0039] Example 1

[0040] like Figures 1 to 6As shown, the present invention provides a three-dimensional micro-metal structure hybrid resonator filter. The structure includes a metal housing 101. Five resonators are disposed within the housing 101, including four cavity resonators and one half-wavelength transmission line resonator. Specifically, the four cavity resonators are a first cavity resonator 102, a second cavity resonator 103, a third cavity resonator 104, and a fourth cavity resonator 105. The first cavity resonator 102, the second cavity resonator 103, the third cavity resonator 104, and the fourth cavity resonator 105 are arranged in a ring. The half-wavelength transmission line resonator is implemented as a transmission line resonator 203, which is located between the second cavity resonator 103 and the third cavity resonator 104. An output coupling structure and an input coupling structure are respectively provided on both sides of the housing 101, wherein the input coupling structure is connected to the first cavity resonator 102 for signal connection, and the output coupling structure is connected to the fourth cavity resonator 105 for signal connection. The output coupling structure and the input coupling structure are respectively used to connect to external components. The external signal is fed into the first cavity resonator 102 of the filter through the input coupling structure, and finally fed into the output coupling structure from the fourth cavity resonator 105 to form a signal path.

[0041] In the present invention, the output coupling structure and the input coupling structure are micro-coaxial line-board-level welding transition structures, which can better feed the filter without taking up too much space, can significantly reduce the size of the filter, and are conducive to board-level integration of the filter with other devices, thereby broadening the application range of the filter.

[0042] Specifically, such as Figure 3 and Figure 5 As shown, the first cavity resonator 102 includes a first cavity opened inside the shell 101, and a first metal column 106 is arranged at the center of the first cavity. One end of the first metal column 106 is connected to the bottom surface of the first cavity, and there is a first gap between the other end and the top surface of the first cavity.

[0043] Specifically, such as Figure 3 and Figure 5 As shown, the second cavity resonator 103 includes a second cavity opened inside the shell 101, and a second metal column 107 is arranged at the center of the second cavity. One end of the second metal column 107 is connected to the bottom surface of the second cavity, and there is a second gap between the other end and the top surface of the second cavity.

[0044] Specifically, such as Figure 7 As shown, the third cavity resonator 104 includes a third cavity opened inside the shell 101, and a third metal column 108 is arranged at the center of the third cavity. One end of the third metal column 108 is connected to the bottom surface of the inside of the third cavity, and there is a third gap between the other end and the top surface of the inside of the third cavity.

[0045] Specifically, the fourth cavity resonator 105 includes a fourth cavity opened inside the shell 101, and a fourth metal column 109 is arranged at the center position of the fourth cavity. One end of the fourth metal column 109 is connected to the bottom surface of the fourth cavity, and there is a fourth gap between the other end and the top surface of the fourth cavity.

[0046] Specifically, the first, second, third, and fourth gaps can each be equivalent to a capacitor, which lowers the resonant frequency of the resonator, thereby facilitating miniaturization of the filter. In the design, the equivalent capacitance can be adjusted by adjusting the first, second, third, and fourth gaps individually.

[0047] In addition, in the design, the resonant frequency of the resonator can be adjusted by adjusting the diameters of the first metal column 106 , the second metal column 107 , the third metal column 108 and the fourth metal column 109 respectively.

[0048] In addition, the transmission line resonator 203 is located inside the housing 101 , between the second cavity resonator 103 and the third cavity resonator 104 , and the transmission line resonator 203 exists as a half-wavelength micro-coaxial transmission line resonator.

[0049] Specifically, as a further refinement of this embodiment, the transmission line resonator 203 includes a fifth cavity and a first metal inner core located inside the fifth cavity. Adjusting the length of the first metal inner core can adjust the resonant frequency of the micro-coaxial transmission line resonator.

[0050] Specifically, the first metal inner core includes a first plate, a second plate, a third plate, a fourth plate and a fifth plate connected end to end in sequence, wherein the second plate, the third plate and the fourth plate are located on a first plane, the second plate and the fourth plate are parallel, the third plate and the fourth plate are perpendicular, the first plate and the fifth plate are located on a second plane, wherein the second plane is perpendicular to the first plane, and the first plate and the fifth plate are in contact with the top of the inner wall of the shell 101 to form a short-circuit structure.

[0051] The coupling path formed by the first cavity resonator 102, the second cavity resonator 103, the transmission line resonator 203, the third cavity resonator 104, and the fourth cavity resonator 105 is as follows: the second cavity resonator 103, the transmission line resonator 203, and the third cavity resonator 104 form a ring-shaped coupling path. The coupling mode of these three resonators is as follows: the coupling mode between the second cavity resonator 103 and the third cavity resonator 104 is cross coupling, and the coupling mode between the second cavity resonator 103 and the transmission line resonator 203, and the coupling mode between the transmission line resonator 203 and the third cavity resonator 104 is primary coupling. The coupling between the first cavity resonator 102 and the second cavity resonator 103, and the coupling between the third cavity resonator 104 and the fourth cavity resonator 105 are both primary coupling, the polarity of the primary coupling is magnetic coupling, and the polarity of the cross coupling is electrical coupling.

[0052] Specifically, the coupling path composed of the first cavity resonator 102, the second cavity resonator 103, the transmission line resonator 203, the third cavity resonator 104 and the fourth cavity resonator 105 can be composed of Figure 11 The first cavity resonator 102 is represented by serial number 1, the second cavity resonator 103 is represented by serial number 2, the transmission line resonator 203 is represented by serial number 3, the third cavity resonator 104 is represented by serial number 4, the fourth cavity resonator 105 is represented by serial number 5, the input coupling structure is represented by S, and the output coupling structure is represented by L.

[0053] Specifically, the structure for achieving magnetic coupling includes coupling window structures on the side walls between the first cavity resonator 102 and the second cavity resonator 103, between the third cavity resonator 104 and the fourth cavity resonator 105, between the second cavity resonator 103 and the transmission line resonator 203, and between the transmission line resonator 203 and the third cavity resonator 104, as well as a release hole structure located on the housing 101. The specific structure is described as follows:

[0054] The coupling between the first cavity resonator 102 and the second cavity resonator 103 is magnetic coupling. In a specific design, a first coupling window 501 is opened between the first cavity resonator 102 and the second cavity resonator 103. The first coupling window 501 is formed by digging out part of the side wall between the first cavity resonator 102 and the second cavity resonator 103. The first coupling window 501 is used to achieve magnetic coupling between the first cavity resonator 102 and the second cavity resonator 103. By adjusting the width of the first coupling window 501, the size of the magnetic coupling between the first cavity resonator 102 and the second cavity resonator 103 can be adjusted.

[0055] The coupling between the third cavity resonator 104 and the fourth cavity resonator 105 is magnetic coupling. In a specific design, a second coupling window 502 is opened between the third cavity resonator 104 and the fourth cavity resonator 105. The second coupling window 502 is formed by digging out a portion of the side wall between the third cavity resonator 104 and the fourth cavity resonator 105. The second coupling window 502 is used to achieve magnetic coupling between the third cavity resonator 104 and the fourth cavity resonator 105. By adjusting the width of the second coupling window 502, the magnitude of the magnetic coupling between the third cavity resonator 104 and the fourth cavity resonator 105 can be adjusted.

[0056] The coupling between the second cavity resonator 103 and the transmission line resonator 203 is magnetic. Specifically, a fourth coupling window 504 is provided on the sidewall of the second cavity resonator 103. This fourth coupling window 504 is formed by removing a portion of the sidewall of the second cavity resonator 103. The first plate on the first metal core is located within the fourth coupling window 504. Furthermore, a first release hole 305 is provided on the housing 101, extending through the bottom surface of the housing 101. The function of the first release hole 305 is to achieve field conversion between the second cavity resonator 103 and the transmission line resonator 203. Adjusting the position of the first release hole 305 can adjust the strength of the magnetic coupling between the second cavity resonator 103 and the transmission line resonator 203.

[0057] The coupling between the transmission line resonator 203 and the third cavity resonator 104 is magnetic. Specifically, a fifth coupling window 505 is provided on the sidewall of the third cavity resonator 104. The fifth coupling window 505 is formed by removing a portion of the sidewall of the third cavity resonator 104. The fifth plate on the first metal core is located within the fifth coupling window 505. Furthermore, a second release hole 306 is provided on the housing 101, extending through the bottom surface of the housing 101. The function of the second release hole 306 is to achieve field conversion between the transmission line resonator 203 and the third cavity resonator 104. Adjusting the position of the second release hole 306 can adjust the strength of the magnetic coupling between the transmission line resonator 203 and the third cavity resonator 104.

[0058] The second cavity resonator 103 and the third cavity resonator 104 are cross-coupled, and the specific coupling method is electrical coupling. In the specific design, a third coupling window 503 is opened between the second cavity resonator 103 and the third cavity resonator 104. The third coupling window 503 is formed by digging out part of the side wall between the second cavity resonator 103 and the third cavity resonator 104. An umbrella-shaped pin 110 is set in the middle of the third coupling window 503. The electrical coupling is achieved with the help of the third coupling window 503 and the umbrella-shaped pin 110.

[0059] like Figure 6As shown, the structure of the umbrella-shaped pin 110 consists of a metal plate 111 and a metal column 112. One end of the metal column 112 is fixed to the bottom of the cavity of the shell 101, and the other end of the metal column 112 is fixed to the metal plate 111. The strength of the electrical coupling can be controlled by adjusting the sizes of the metal column 112 and the metal plate 111 and the width of the third coupling window 503. The umbrella-shaped pin 110 can generate a transmission zero in the high-frequency stop band while providing electrical coupling.

[0060] like Figures 3 to 5 As shown, the input coupling structure includes a third release hole 303 and a second metal core 201. Specifically, the second metal core 201 exists in the form of a transmission line. One end of the second metal core 201 is located in the first cavity resonator 102. A first opening 506 is opened on the bottom surface of the shell 101. The other end of the second metal core 201 is located in the first opening 506. An air gap structure is formed between the periphery of the second metal core 201 and the inner wall of the first opening 506. The second metal core 201 and the first opening 506 form an air gap. The interface for interconnecting with external components, the first through-hole 506 exposes the end of the second metal core 201, which is convenient for connection with a test probe or a dielectric substrate, and is used to realize the transmission of signals from the second metal core 201 to the first cavity resonator 102. The third release hole 303 is opened on the bottom surface of the shell 101, located on the lower side of the second metal core 201, and is used to complete the field conversion from the second metal core 201 to the first cavity resonator 102, and excite the resonant mode of the first cavity resonator 102 to realize the excitation of the filter.

[0061] Specifically, such as Figure 10 As shown, the second metal core 201 includes a sixth plate 204, a seventh plate 205 and an eighth plate 206 connected in sequence, wherein the sixth plate 204 and the eighth plate 206 are parallel, the sixth plate 204 and the seventh plate 205 are perpendicular, the end of the sixth plate 204 away from the seventh plate 205 is fixed to the top of the cavity of the shell 101, and the end of the eighth plate 206 away from the seventh plate 205 is arranged in the first through opening 506 and the end face of the eighth plate 206 is flush with the surface of the shell 101.

[0062] Specifically, such as Figure 3 As shown, the third release hole 303 is in a pincer shape.

[0063] like Figures 3 to 5 As shown, the output coupling structure has the same structure as the input coupling structure, specifically, it includes a fourth release hole 304 and a third metal inner core 202. The third metal inner core 202 exists in the form of a transmission line. One end of the third metal inner core 202 is located in the fourth cavity resonator 105, as shown in FIG. Figure 8As shown, a second opening 507 is provided on the bottom surface of the shell 101, and the other end of the third metal core 202 is located in the second opening 507. An air gap structure is formed between the four sides of the third metal core 202 and the inner wall of the second opening 507. The third metal core 202 and the second opening 507 constitute an interface for interconnecting with external components. The second opening 507 exposes the end of the third metal core 202 to facilitate connection with a test probe or a dielectric substrate, so as to realize signal transmission from the fourth cavity resonator 105 to the third metal core 202. The fourth release hole 304 is provided on the bottom surface of the shell 101, located on the lower side of the third metal core 202, and is used to complete the field conversion from the fourth cavity resonator 105 to the third metal core 202.

[0064] Specifically, such as Figures 8 to 10 As shown, the structure of the third metal core 202 is the same as that of the second metal core 201. The third metal core 202 includes a ninth plate, a tenth plate and an eleventh plate 207 connected in sequence, wherein the ninth plate and the eleventh plate 207 are parallel, the ninth plate and the tenth plate are perpendicular, one end of the ninth plate away from the tenth plate is fixed to the top of the cavity of the shell 101, and one end of the eleventh plate 207 away from the tenth plate is arranged in the second through opening 507 and the end face of the eleventh plate 207 is flush with the surface of the shell 101.

[0065] Specifically, such as Figure 3 As shown, the fourth release hole 304 and the third release hole 303 have the same structure and are both pincer-shaped.

[0066] Furthermore, in order to improve the performance of the transmission line, a portion of the seventh plate 205 is cut away at the downwardly bent portion to form a step structure.

[0067] In addition, the cross-sectional dimension of a section of the eighth board 206 disposed in the first through opening 506 is slightly smaller than that of other sections. This end is used as a test contact for transfer connection, which enables the filter to have board-level integration capability.

[0068] For performance and ease of processing, the filter provided by the present invention utilizes an electrochemical additive manufacturing process. To release the photoresist used during the manufacturing process, a plurality of fifth release holes 301 and sixth release holes 302 are provided in the housing 101. All fifth release holes 301 and all sixth release holes 302 are of the same size. It is important to note that the number of fifth release holes 301 and sixth release holes 302 should be neither too large nor too small. Too many holes can cause electromagnetic leakage, while too few holes can lead to incomplete photoresist removal, resulting in residual photoresist. Therefore, the number should be determined after comprehensive consideration during the design process.

[0069] In addition, in order to realize the positioning function of the first metal core, the second metal core 201 and the third metal core 202, a first dielectric support bar 401 is passed through the second metal core 201, a second dielectric support bar 402 is passed through the third metal core 202, a third dielectric support bar 405 is passed through the third plate body of the first metal core, a fourth dielectric support bar 403 is passed through the first plate body of the first metal core, and a fifth dielectric support bar 404 is passed through the fifth plate body of the first metal core. One pair of side surfaces of the first dielectric support bar 401, the second dielectric support bar 402, the third dielectric support bar 405, the fourth dielectric support bar 403 and the fifth dielectric support bar 404 are respectively fixed to a pair of inner walls of the shell 101 to improve the stability of the support for the first metal core, the second metal core 201 and the third metal core 202.

[0070] like Figure 12 As shown in the figure, after simulation design experiments, the 1dB passband range of the filter in this specific implementation is 92GHz-96GHz, the minimum insertion loss in the band is 1.24dB, the return loss is better than 18dB, and there is a zero point at 90.26GHz and 102.18GHz respectively. The out-of-band suppression at 90.2GHz is better than 45dB, and it has high frequency band selectivity.

[0071] Compared with existing similar technologies, the three-dimensional micro-metal structure hybrid resonator filter provided by the present invention uses the basic design method of cross-coupling filter, making the coupling structure between the designed cavity resonator and transmission line resonator relatively simple and easy to implement, combining the advantages of high quality factor of cavity resonator and miniaturization of transmission line resonator, further improving the integration and design flexibility of the filter, facilitating micro-nano processing by electrochemical additive manufacturing process, and facilitating mass production while ensuring the excellent performance of the filter. At the same time, the hybrid resonator filter provided by the present invention has a micro-coaxial line-board level welding transition structure, which can better feed the filter without taking up too much space, significantly reducing the size of the filter, facilitating board-level integration of the filter with other devices, and broadening the application range of the filter. In addition, since the hybrid resonator filter abandons the traditional dielectric substrate, it avoids the influence of radiation loss and dielectric loss, reduces the insertion loss of the hybrid resonator filter, and has the high-frequency, low-loss, and high-selectivity working advantages that traditional dielectric plate circuits do not have, and can be applied in higher frequency bands such as W band.

[0072] It will be understood that the present invention is described through some embodiments, and those skilled in the art will appreciate that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention.

[0073] Furthermore, these features and embodiments may be modified to suit specific circumstances and materials under the teachings of the present invention without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of the present invention are intended to be protected by the present invention.

Claims

1. A three-dimensional micro-metal structure hybrid resonator filter, characterized in that: include: A housing (101) made of metal; The first cavity resonator (102), the second cavity resonator (103), the third cavity resonator (104) and the fourth cavity resonator (105) are located in the housing (101) and are arranged in a ring shape; the first cavity resonator (102) and the second cavity resonator (103), the third cavity resonator (104) and the fourth cavity resonator (105), the second cavity resonator (103) and the transmission line resonator (203), and the transmission line resonator (203) and the third cavity resonator (104) are all magnetically coupled; and the second cavity resonator (103) and the third cavity resonator (104) are electrically coupled; a transmission line resonator (203) located between the second cavity resonator (103) and the third cavity resonator (104); The output coupling structure and the input coupling structure are both micro-coaxial line-board-level welding transition structures, which are respectively arranged on both sides of the housing (101), wherein the input coupling structure is connected to the first cavity resonator (102) for signal connection, and the output coupling structure is connected to the fourth cavity resonator (105) for signal connection; after the input coupling structure feeds the signal into the first cavity resonator (102) of the filter, the signal is fed into the output coupling structure by the fourth cavity resonator (105); the transmission line resonator (203) includes a fifth cavity and A first metal inner core is located inside the fifth cavity, the first metal inner core comprises a first plate, a second plate, a third plate, a fourth plate and a fifth plate connected end to end in sequence, wherein the second plate, the third plate and the fourth plate are located on a first plane, the second plate and the fourth plate are parallel, the third plate and the fourth plate are perpendicular, the first plate and the fifth plate are located on a second plane, the second plane is perpendicular to the first plane, and the first plate and the fifth plate are both in contact with the top of the inner wall of the shell (101) to form a short-circuit structure.

2. The three-dimensional micrometal structure hybrid resonator filter according to claim 1, characterized in that: The first cavity resonator (102), the second cavity resonator (103), the third cavity resonator (104) and the fourth cavity resonator (105) have the same structure. The first cavity resonator (102) includes a first cavity opened inside the shell (101). A first metal column (106) is provided at the center of the first cavity. One end of the first metal column (106) is connected to the bottom surface of the first cavity, and a first gap is formed between the other end and the top surface of the first cavity.

3. The three-dimensional micrometal structure hybrid resonator filter according to claim 2, characterized in that: The structure for realizing the magnetic coupling comprises a coupling window structure on the side wall between the first cavity resonator (102) and the second cavity resonator (103), between the third cavity resonator (104) and the fourth cavity resonator (105), between the second cavity resonator (103) and the transmission line resonator (203), and between the transmission line resonator (203) and the third cavity resonator (104), and a release hole structure located on the shell (101).

4. The three-dimensional micrometal structure hybrid resonator filter according to claim 3, characterized in that: The structure for realizing the electrical coupling comprises a third coupling window (503) and an umbrella-shaped pin (110), wherein the third coupling window (503) is opened on the side wall between the second cavity resonator (103) and the third cavity resonator (104), and the umbrella-shaped pin (110) is located in the middle of the third coupling window (503) and is used to generate a transmission zero point in the high-frequency stop band while providing electrical coupling.

5. The three-dimensional micrometal structure hybrid resonator filter according to claim 4, characterized in that: The umbrella-shaped pin (110) comprises a metal flat plate (111) and a metal column (112), one end of the metal column (112) is fixed to the bottom of the cavity of the housing (101), and the other end of the metal column (112) is fixed to the metal flat plate (111).

6. The three-dimensional micrometal structure hybrid resonator filter according to claim 1, characterized in that: The output coupling structure has the same structure as the input coupling structure, and the input coupling structure includes a third release hole (303) and a second metal inner core (201), one end of the second metal inner core (201) is located in the first cavity resonator (102), a first opening (506) is provided on the bottom surface of the shell (101), the other end of the second metal inner core (201) is located in the first opening (506), and an air gap structure is formed between the periphery of the second metal inner core (201) and the inner wall of the first opening (506). The second metal inner core (201) and the first opening (506) form an interface interconnected with an external component, which is used to realize the transmission of signals from the second metal inner core (201) to the first cavity resonator (102). The third release hole (303) is opened on the bottom surface of the shell (101), located on the lower side of the second metal inner core (201), and is used to complete the field conversion from the second metal inner core (201) to the first cavity resonator (102), and to excite the resonant mode of the first cavity resonator (102) to realize the excitation of the filter.

7. The three-dimensional micrometal structure hybrid resonator filter according to claim 6, characterized in that: The second metal inner core (201) comprises a sixth plate (204), a seventh plate (205) and an eighth plate (206) connected in sequence, wherein the sixth plate (204) and the eighth plate (206) are parallel, and the sixth plate (204) and the seventh plate (205) are perpendicular, and one end of the sixth plate (204) away from the seventh plate (205) is fixed to the top of the cavity of the shell (101), and one end of the eighth plate (206) away from the seventh plate (205) is arranged in the first through opening (506) and the end face of the eighth plate (206) is flush with the surface of the shell (101).

8. The three-dimensional micrometal structure hybrid resonator filter according to claim 7, characterized in that: The seventh plate (205) is a stepped structure.

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