A miniaturized sheet metal combiner

Abstract

The present invention provides a miniaturized sheet metal combiner, in which the front and rear ends of each resonant plate are bent upward to form a bent structure for coupling adjacent resonant plates. The coupling is enhanced by adjusting the distance and relative area between the bent structures of adjacent resonant plates, thereby achieving adjustment of the coupling bandwidth. Under volume constraints, the height and volume of the bent structure are significantly reduced compared to the general coaxial metal solution. At the same time, a tuning channel is provided on the cover plate above the bent structure of any two adjacent resonant plates, and the distance and relative area of the bent structure are changed by prying the tuning channel on the cover plate, thereby effectively enhancing the coupling, reducing the number of debugging parts, and saving costs. Moreover, the present invention adjusts the performance of the combiner through the sheet metal resonant plates and the flying rod plates and connecting rods that generate capacitive and inductive cross coupling. While achieving the same frequency index, the overall weight is significantly reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of sheet metal combiners, and in particular to a miniaturized sheet metal combiner. Background Art

[0002] Combiners primarily address the requirements of various operators for antenna sharing and distribution systems for multi-band, multi-standard mobile communications and wireless transmission, enabling dual-band, tri-band, and other multi-band combining capabilities. With the advancement from 1G to 5G, the number of available frequency bands is increasing, and combiners enable a single indoor distributed system to operate simultaneously in multiple frequency bands. In radio communication systems, this not only saves on feeder cables but also eliminates the hassle of switching between different antennas. High performance, miniaturization, and integration are key development trends for mobile communication equipment.

[0003] There are three main technical solutions for existing combiners. The first is the metal cavity solution: the metal cavity combiner has a solid structure, stable performance, good heat dissipation performance and mature engineering application technology. However, for low-frequency broadband combiners, it mainly enhances coupling through coupling ribs. At the same time, the problem it brings is that it is large in size, heavy in weight and difficult to integrate; the second is the ceramic dielectric solution: the ceramic dielectric combiner is small in size, easy to integrate with antenna equipment, has low insertion loss, high Q value and light weight, but the ceramic dielectric firing process is complex, the yield rate is low, and the consistency of mass production is poor; the polishing process requires high precision, the polishing process is irreversible, and the scrap rate is high; another difficulty lies in the brittleness of the ceramic material. Under external load, the fracture is sudden and without warning; the third is the sheet metal resonant plate solution: the sheet metal resonant plate combiner is small in size and light in weight. The sheet metal resonant plate is easy to process and assemble, and has a simple and stable structure. For broadband combiners, while achieving the same electrical performance, the volume and weight are greatly reduced, which is convenient for integration with the antenna.

[0004] The development of mobile communication networks, multi-band communication systems, and the miniaturization requirements of the 5G era have promoted the development of miniaturized combiners. The aforementioned filter solutions all have their advantages and disadvantages. As we all know, in RF products, the lower the frequency, the larger the product size. Therefore, how to design a low-frequency sheet metal resonator that meets the requirements of miniaturization and lightweighting has always been a technical problem that needs to be solved in this field. Summary of the Invention

[0005] In view of this, an object of the present invention is to provide a miniaturized sheet metal combiner to solve the technical problems mentioned in the background technology.

[0006] To achieve the above-mentioned object, the technical solution adopted by the present invention is: a miniaturized sheet metal combiner, comprising a cavity and a cover plate mounted on the cavity, a plurality of tuning screws that can be screwed into the cavity are mounted on the cover plate, a plurality of ports are provided on the outer wall of the cavity, a plurality of filter branches are provided in the cavity for filtering network signals of different frequency bands, and the ends of the plurality of filter branches are coupled to the corresponding ports through taps;

[0007] Each filter branch consists of several resonant plates coupled in sequence. The front and rear ends of each resonant plate are bent upward to form a bending structure for coupling adjacent resonant plates. By adjusting the distance and relative area between the bending structures of adjacent resonant plates, the coupling is enhanced and the coupling bandwidth is adjusted.

[0008] Furthermore, a tuning channel penetrating through the end surface of the cover is provided in the area on the cover above the bent structure of any two adjacent resonant plates.

[0009] Furthermore, the tuning channel is a plurality of paddle tuning holes arranged at intervals, and the plurality of paddle tuning holes are distributed in sequence along the length direction of the bending structure.

[0010] Furthermore, at least one tuning screw is provided above each resonant plate, and the resonant cavity frequency is controlled by adjusting the extension amount of the tuning screw.

[0011] Furthermore, a partition wall is provided between any two adjacent filter branches to separate the two.

[0012] Furthermore, each filtering branch may be selectively provided with a flying rod for realizing capacitive cross-coupling and a connecting rod for realizing inductive cross-coupling.

[0013] Furthermore, a resonance column for overlapping the connecting rod / flying rod plate is provided on one side of each resonance plate, and the end of the resonance plate close to the resonance column has a connection section connected to the resonance column.

[0014] Furthermore, the two ends of the flying rod piece are respectively fixed above the connecting sections of the corresponding two resonant plates by dielectric rivets, and there is no contact between the flying rod piece and the resonant plates; the two ends of the connecting rod are respectively welded to the connecting sections of the corresponding two resonant plates.

[0015] Furthermore, the connecting section for welding the connecting rod has a welding portion for supporting the connecting rod.

[0016] Furthermore, the resonant plate, the bending structure, the connecting section and the welding portion are an integrally formed sheet metal structure.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] 1. The present invention bends the front and rear ends of each resonant plate upward to form a bent structure for coupling adjacent resonant plates. By adjusting the distance and relative area between the bent structures of adjacent resonant plates, coupling is enhanced, achieving adjustment of the coupling bandwidth. Given limited volume, the present invention significantly reduces the height and volume of the bent structure compared to common coaxial metal solutions, a key advantage of this miniaturized sheet metal low-frequency combiner.

[0019] 2. A tuning channel is provided on the cover plate above the bent structure of any two adjacent resonant plates. The tuning channel on the cover plate can be used to change the distance and relative area of the bent structure, effectively enhancing coupling, reducing debugging parts, and saving costs.

[0020] 3. The present invention adjusts the performance of the combiner through the sheet metal resonant plate and the flying rod plate and connecting rod that generate capacitive and inductive cross coupling. While achieving the same frequency index, the overall weight is significantly reduced;

[0021] 4. The sheet metal material and structure design of the present invention has strong market competitiveness in low-frequency combiners. Moreover, the solution is not limited to low-frequency combiners, but can also be applied to the design of RF devices with miniaturization requirements, and has strong practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A schematic structural diagram of a miniaturized sheet metal combiner provided in an embodiment of the present invention;

[0023] Figure 2 An exploded view of a miniaturized sheet metal combiner provided in an embodiment of the present invention;

[0024] Figure 3 A schematic diagram of a simulation of a miniaturized sheet metal combiner provided in an embodiment of the present invention;

[0025] Figure 4 Schematic diagram comparing the sheet metal single cavity structure using the technical solution of the present invention with the existing single cavity technology;

[0026] Figure 5 Schematic diagram comparing the sheet metal dual-cavity structure using the technical solution of the present invention with the existing dual-cavity technology;

[0027] Figure 6 This is a schematic diagram of the structure of the existing metal coaxial solution covering the three low-frequency bands of 713-798, 811-862, and 880-960 MHz;

[0028] Markings in the figure: 1. Cavity, 2. Paddle tuning hole, 3. Cover plate, 4. Screw tuning hole, 5. Tuning screw, 6. Resonance plate, 7. First tap plate, 8. First connecting rod, 9. First flying rod plate, 10. Second connecting rod, 11. Second flying rod plate, 12. Dielectric rivet, 13. Second tap plate, 14. Resonance column. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0030] In RF products, the lower the frequency, the larger the product size. The low-frequency sheet metal resonator of this invention meets the requirements of miniaturization and lightweighting. Compared with existing technical solutions, the low-frequency sheet metal combiner with limited size has more prominent advantages and strong market competitiveness.

[0031] The principle of the present invention is as follows: The present invention is aimed at the existing low-frequency combiner design scheme, and is innovatively designed on the basis of the general design scheme, which can significantly reduce the volume, reduce the weight and innovate the debugging method, and is more suitable for engineering application. The cavity and the resonant plate of the sheet metal material of the technical solution of the present invention are made by die-casting or machining. The design of the bending structure makes the volume of the single cavity smaller, and the coupling adjustment method is different from the common debugging screws, debugging metal resonators and the emerging polished dielectric ceramic resonators. Moreover, the technical solution of the present invention adjusts the bending structure to adjust the coupling by means of a paddle, which is suitable for miniaturized low-frequency combiners and can adapt to the development trend of multi-band communication systems and high integration of communication equipment in the 5G era.

[0032] The following invention uses a three-band sheet metal combiner covering three low-frequency bands of 713-798 & 811-862 & 880-960 MHz as an example to illustrate the technical solution of the present invention:

[0033] like Figure 1 FIG. 1 is a schematic structural diagram of a miniaturized sheet metal combiner provided in this embodiment. Figure 2 The decomposition diagram is as follows: Figure 3 The following is a simulation diagram. In the figure, port 1 corresponds to the public port, port 2 corresponds to the frequency bands 713-798 & 880-960 MHz, and port 3 corresponds to 811-862 MHz.

[0034] The miniaturized sheet metal combiner mainly includes a cavity 1, a tuning screw 5, a cover plate 3, a resonant plate 6, a tap plate and a dielectric rivet 12. A cover plate 3 for sealing the cavity opening is provided above the cavity 1. A tuning screw 5 that can be screwed into the cavity is installed on the cover plate 3. A plurality of filter branches are provided in the cavity 1 for filtering network signals of different frequency bands. The two ends of the plurality of filter branches are coupled to the corresponding ports through tap plates.

[0035] Each filter branch is composed of several resonant plates 6 coupled in sequence. The front and rear ends of each resonant plate 6 are bent upward to form a bending structure for coupling adjacent resonant plates. The coupling is enhanced by adjusting the distance and relative area between the bending structures of adjacent resonant plates, thereby achieving adjustment of the coupling bandwidth.

[0036] In this embodiment, at least one tuning screw 5 is positioned above each resonant plate 6. Adjusting the extension of the tuning screw 5 controls the resonant cavity frequency. Each pair of adjacent resonant plates has at least two paddle tuning holes 2 above the bent structure. The distance between the bent structures is adjusted by prying at the paddle tuning holes 2 to control the coupling. The left-side zero point generated by the cross-coupling is controlled by the first and second flyer rods 9 and 11, while the right-side zero point generated by the cross-coupling is adjusted by the first and second connecting rods 8 and 10.

[0037] Furthermore, the cavity 1 is made of aluminum, and the inner surface of the cavity is silver-plated. The cavity 1 is made by die-casting or machining, and is also provided with a resonant column 14 and a dielectric rivet 12 for fixing the resonant plate 6.

[0038] The first tap piece 7 and the second tap piece 13 are fixed by dielectric rivets 12, and then the sheet metal resonant piece 6 is installed, and then the specific positions of the first tap piece 7, the second tap piece 13 and each resonant piece 6 are fixed by welding.

[0039] The resonant plate 6 is a sheet metal thin film structure, and a resonant column 14 for overlapping the connecting rod / flying rod plate is provided on one side of each resonant plate, and the resonant plate 6 has a connecting section connected to the resonant column at one end close to the resonant column. The connecting section is fixed to the resonant column 14 by screws, and the resonant plate 6 is fixed to the cavity 1 by a dielectric rivet 12.

[0040] In this embodiment, the resonant plate 6 is very thin, and the front end of the resonant plate 6 is bent upward by 90°. It should be noted that the design of the bending structure should ensure that the bending structure can be pried through the paddle tuning hole 2 on the cover plate. Furthermore, the paddle tuning hole 2 is provided with multiple paddle tuning holes, and the multiple paddle tuning holes are sequentially distributed along the length of the bending structure. Of course, the paddle tuning holes 2 are not limited to a multiple hole structure and can also be provided as a straight groove structure. This innovative coupling debugging method reduces the coupling ribs and coupling screws of the coaxial resonant rod design, reducing the weight by more than half, effectively reducing product weight and assembly parts, and improving production efficiency.

[0041] Furthermore, the first flying rod piece 9 and the second flying rod piece 11 generating capacitive cross-coupling are fixed above the resonant plate 6 via dielectric rivets 12, ensuring that the flying rod pieces do not contact the resonant plate 6. The first connecting rod 8 and the second connecting rod 10 generating inductive cross-coupling are fixed above the resonant plate 6 by welding. To prevent the connecting rods from contacting the middle resonant plate, this embodiment further provides a welding portion for supporting the connecting rod on the connecting section for welding the connecting rod. The resonant plate 6, the bending structure, the connecting section, and the welding portion are an integrally formed sheet metal structure.

[0042] In this embodiment, the cover plate 3 is made of aluminum with a silver-plated lower surface. A welded design is employed to accommodate the size requirements of miniaturized RF devices and facilitate antenna filter integration. The tuning screw 5 is made of silver-plated brass and screws through the cover plate into the cavity 1. After assembly, solder paste is applied to the upper surface of the cavity 1, and the cover plate 3 is sealed to the cavity 1 via high-temperature reflow soldering.

[0043] Figure 4 This is a schematic diagram comparing the sheet metal single-cavity structure using the technical solution of the present invention with the existing single-cavity technology. As shown in the figure, the sheet metal single-cavity structure using the technical solution of the present invention has a volume reduced by about 33% relative to the metal coaxial single cavity. Compared with the common metal coaxial solution, the sheet metal resonant plate can be greatly reduced in size and weight; in addition, compared with the currently popular ceramic dielectric filter, the technical solution of the present invention has better resistance to mechanical impact and sudden temperature changes, and the material is conventional.

[0044] Figure 5 This is a schematic diagram comparing the sheet metal dual-cavity structure using the technical solution of the present invention with the existing dual-cavity technology. Figure 6 This is a schematic diagram of the structure of the existing metal coaxial solution covering the three low-frequency bands of 713-798 & 811-862 & 880-960 MHz. After calculation, the three-band sheet metal combiner of the present invention is Figure 6The existing metal coaxial solution shown in the figure has a height reduction of 20.5 mm while maintaining a similar base area, resulting in an overall volume reduction of approximately 55%, and a weight reduction from 1.1 kg of the coaxial metal solution to approximately 0.4 kg.

[0045] In summary, the low-frequency combiner design provided by the embodiments of the present invention for 713-798, 811-862, and 880-960 MHz (51-85 MHz bandwidth) has the following advantages:

[0046] 1) With limited space, the bent structure formed by the resonant plate, with both its front and rear ends bent upward, reduces the height by more than half and the volume by 55% compared to conventional coaxial metal solutions. This is a key advantage of this miniaturized sheet metal low-frequency combiner.

[0047] 2) By changing the distance and relative area of the bending structure through the paddle, the coupling is effectively enhanced, the number of debugging parts is reduced, and the cost is saved;

[0048] 3) The thin sheet metal resonator, the flying rod and the connecting rod that generate capacitive and inductive cross coupling, reduce the overall weight by about 64% while achieving the same frequency performance.

[0049] 4) The sheet metal material and structure design of the present invention has strong market competitiveness in low-frequency combiners, and the solution is not limited to low-frequency combiners, but can be applied to the design of RF devices with miniaturization requirements.

[0050] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A miniaturized sheet metal combiner comprising a cavity and a cover mounted on the cavity, wherein the cover is mounted with a plurality of tuning screws that can be screwed into the cavity, and a plurality of ports are provided on the outer wall of the cavity, characterized in that: The cavity is provided with a plurality of filter branches for filtering network signals of different frequency bands, and both ends of the plurality of filter branches are coupled to corresponding ports through taps. Each filter branch consists of several resonant plates coupled in sequence. The front and rear ends of each resonant plate are bent upward to form a bending structure for coupling adjacent resonant plates. By adjusting the distance and relative area between the bending structures of adjacent resonant plates, the coupling is enhanced and the coupling bandwidth is adjusted. A tuning channel is provided on the cover plate in an area above the bent structure of any two adjacent resonant plates, penetrating the end surface of the cover plate; The tuning channel is a plurality of paddle tuning holes arranged at intervals, and the plurality of paddle tuning holes are sequentially distributed along the length direction of the bending structure, and the distance of the bending structure is adjusted by plucking at the paddle tuning holes.

2. The miniaturized sheet metal combiner according to claim 1, characterized in that: At least one tuning screw is provided above each resonant plate, and the resonant cavity frequency is controlled by adjusting the extension amount of the tuning screw.

3. The miniaturized sheet metal combiner according to claim 2, characterized in that: A partition wall is provided between any two adjacent filter branches to separate the two.

4. A miniaturized sheet metal combiner according to any one of claims 1 to 3, characterized in that: Each filter branch is provided with a flying rod for realizing capacitive cross coupling and a connecting rod for realizing inductive cross coupling.

5. The miniaturized sheet metal combiner according to claim 4, characterized in that: A resonance column for overlapping a connecting rod or a flying rod piece is provided on one side of each resonance piece, and an end of the resonance piece close to the resonance column is provided with a connection section connected to the resonance column.

6. The miniaturized sheet metal combiner according to claim 5, characterized in that: The two ends of the flying rod piece are respectively fixed above the connecting sections of the corresponding two resonant plates by dielectric rivets, and there is no contact between the flying rod piece and the resonant plate; the two ends of the connecting rod are respectively welded to the connecting sections of the corresponding two resonant plates.

7. The miniaturized sheet metal combiner according to claim 6, characterized in that: The connecting section for welding the connecting rod is provided with a welding portion for supporting the connecting rod.

8. The miniaturized sheet metal combiner according to claim 7, characterized in that: The resonant plate, the bending structure, the connecting section and the welding portion are an integrally formed sheet metal structure.

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