A dielectric duplexer based on a new common cavity structure

Abstract

The invention provides a dielectric duplexer based on a novel common cavity structure, belonging to the technical field of communication equipment, comprising: an upper filter, a lower filter and a common cavity structure, wherein the dielectric resonant cavity of the common cavity structure is coupled and connected with the dielectric resonant cavity of the upper filter and the lower filter respectively; a tap feeder structure is provided on the common cavity structure, wherein the tap feeder structure is composed of a punched metal through hole and an empty slot formed by digging out a dielectric block at the bottom of the metal through hole; the dielectric duplexer of the invention has a tap feeder structure on the common cavity structure, wherein the metal through hole of the tap feeder structure can be used as a quarter-wavelength resonance unit, and by adjusting the height of the empty slot below the metal through hole, it can be equivalent to adjusting the length of the resonance unit, thereby adjusting the external coupling, and the feeding form can provide broadband source coupling, thereby solving the problem of insufficient energy when feeding two channels of the dielectric duplexer.

Description

Technical Field

[0001] The present invention relates to the technical field of communication equipment, and in particular to a dielectric duplexer based on a novel common cavity structure. Background Art

[0002] Microwave duplexer is one of the basic components in mobile communication, radar, satellite, ship and other systems. It mainly realizes important functions such as noise filtering, combining and frequency selection. In recent years, with the rapid development of mobile communication, the resources of wireless spectrum are becoming more and more limited. The new communication form puts forward stringent requirements for RF microwave duplexer, such as integration, high performance, mass production and low cost. The traditional metal coaxial air cavity duplexer can no longer meet the requirements of large-scale MIMO system. The dielectric resonator can greatly reduce the size of the duplexer due to the high dielectric constant of the internal material. At the same time, with better firing, electroplating process and debugging means, the dielectric duplexer can achieve low-cost and high-yield mass production. Under this application demand and the background of communication development, dielectric duplexer has also become a hot topic of scientific research.

[0003] There is a huge demand for dielectric duplexers in the 5G FDD standard. Although each channel of the dielectric duplexer is a single filter, the design of the dielectric duplexer must not only meet the in-band loss and standing wave indicators, but also often requires steep out-of-band characteristics and flat in-band group delay characteristics. At the same time, due to the relatively fragmented division of 5G spectrum resources, the two frequency bands of the duplexer may be far apart, which increases the complexity of the duplexer's order and topological structure, and also brings challenges to the external coupling bandwidth, adding a lot of difficulty to simulation optimization and later debugging. Summary of the invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the defect of the dielectric duplexer in the prior art that insufficient power is supplied to the two frequency bands when the two frequency bands are far apart, thereby providing a dielectric duplexer based on a novel common cavity structure.

[0005] In order to solve the above technical problems, the present invention provides a dielectric duplexer based on a novel common cavity structure, comprising: an upper filter, a lower filter and a common cavity structure, wherein the upper filter, the lower filter and the common cavity structure respectively have a dielectric resonant cavity, and the dielectric resonant cavity of the common cavity structure is coupled and connected with the dielectric resonant cavity of the upper filter and the dielectric resonant cavity of the lower filter respectively;

[0006] A tap feeder structure is provided on the common cavity structure. The tap feeder structure is composed of a punched metal through hole and an empty groove formed by digging out a dielectric block at the bottom of the metal through hole.

[0007] Optionally, the dielectric resonant cavity of the common cavity structure and the dielectric resonant cavity of the lower filter are connected via a bent waveguide coupling.

[0008] Optionally, coupling windows are respectively provided at coupling connections between the two ends of the curved waveguide and the dielectric resonant cavity.

[0009] Optionally, the coupling window is rectangular.

[0010] Optionally, the upper filter and the lower filter are both provided with a plurality of dielectric resonant cavities.

[0011] Optionally, a magnetic field compression through hole is respectively provided on the first dielectric resonant cavity of the upper filter and the lower filter for coupling with the dielectric resonant cavity of the common cavity structure.

[0012] Optionally, at least one coupling debugging hole is respectively provided on the upper filter and the lower filter.

[0013] Optionally, on the upper filter and the lower filter, each dielectric resonant cavity is provided with a debugging blind hole respectively.

[0014] Optionally, on the upper filter and the lower filter, the adjustment blind holes of the last dielectric resonant cavity away from the common cavity structure are respectively located on opposite surfaces of the upper filter and the lower filter; on the upper filter and the lower filter, taps are respectively provided on the surfaces opposite to the tuning blind holes of the last dielectric resonant cavity.

[0015] Optionally, the plurality of dielectric resonant cavities on the upper filter and the lower filter are separated by a separation wall, and the separation wall is a strip groove formed by digging out a dielectric block.

[0016] The technical solution of the present invention has the following advantages:

[0017] 1. The dielectric duplexer based on the novel common cavity structure provided by the present invention is coupled and connected between the upper filter and the lower filter through the common cavity structure, and has a tap feeder structure on the common cavity structure, wherein the tap feeder structure includes a metal through hole, which can be used as a quarter-wavelength resonance unit, and the metal through hole can be used to excite a transverse electromagnetic mode (TEM); in addition, by adjusting the height of the empty slot below the metal through hole, it can be equivalent to adjusting the length of the resonance unit, thereby adjusting the external coupling; this feeding form can provide broadband source coupling, solving the problem of insufficient energy when feeding two channels of the dielectric duplexer.

[0018] 2. The dielectric duplexer based on the novel common cavity structure provided by the present invention couples the upper and lower dielectric resonant cavities through a curved waveguide. Coupling windows are respectively provided at the coupling connections at both ends of the curved waveguide. By adjusting the size of the coupling window, the coupling strength of the corresponding two dielectric resonant cavities can be adjusted.

[0019] 3. The dielectric duplexer based on the novel common cavity structure provided by the present invention is provided with magnetic field compression holes on the upper filter and the lower filter respectively. Since the first dielectric resonant cavity on the upper filter and the lower filter is greatly affected by the dielectric resonant cavity of the common cavity structure, the self-resonant frequency is lowered, and this problem can be improved by using the magnetic field compression holes. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 It is a stereoscopic diagram of a specific implementation manner of the common cavity structure of the dielectric duplexer provided in the embodiment of the present invention.

[0022] Figure 2 for Figure 1 The main cross-sectional view of the common cavity structure along line AA.

[0023] Figure 3 for Figure 1 An exploded view of the common cavity structure cut along line BB.

[0024] Figure 4 for Figure 1 Group delay simulation results for the common cavity structure shown in .

[0025] Figure 5 It is a three-dimensional diagram of a specific implementation manner of the dielectric duplexer provided in an embodiment of the present invention.

[0026] Figure 6 for Figure 5 An exploded view of the dielectric duplexer in FIG. 1 , taken along line CC.

[0027] Figure 7 for Figure 5 An exploded view of the dielectric duplexer in FIG. 1 , taken along line DD.

[0028] Figure 8 for Figure 7 A three-dimensional diagram of the bottom structure of the dielectric duplexer shown in FIG.

[0029] Fig. 9 for Figure 5 Frequency response diagram of the dielectric duplexer shown in .

[0030] Description of reference numerals:

[0031] 1. Input connector; 2. Bend waveguide; 3. Metal through hole; 4. Empty slot; 5. Coupling window; 6. Upper filter; 7. Lower filter; 8. Isolation wall; 9. Blind hole; 10. Tap; 11. Coupling debugging hole; 12. Magnetic field compression through hole. DETAILED DESCRIPTION

[0032] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying 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 limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0034] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0035] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0036] This embodiment provides a dielectric duplexer based on a novel common cavity structure, such as Figure 1As shown, the novel common cavity structure includes: an upper dielectric resonant cavity and a curved waveguide, the curved waveguide can be equivalent to a transmission line, and the upper dielectric resonant cavity is coupled to the curved waveguide. A tap feeder structure is provided on the dielectric block of the upper dielectric resonant cavity, the tap feeder structure includes an input connector, and an empty slot is formed by digging out the dielectric block below the input connector. The tap feeder structure can simultaneously meet the external coupling requirements of the two filter channels of the dielectric duplexer.

[0037] like Figure 2 As shown, a metal through hole is punched in the middle of the input connector, and the metal through hole is connected to the bottom empty slot. The metal through hole can be used as a quarter-wavelength resonance unit, and the metal through hole can be used to excite a transverse electromagnetic mode (TEM); in addition, by adjusting the height H of the empty slot, it can be equivalent to adjusting the length of the resonance unit, thereby adjusting the external coupling. When the above-mentioned common cavity is used to couple the two filters of the dielectric duplexer, the upper dielectric resonant cavity is coupled with the dielectric resonant cavity of one filter, and the second end of the curved waveguide is coupled with the dielectric resonant cavity of the other filter. The curved waveguide is used to solve the problem of insufficient coupling between the dielectric resonant cavities of the filters located in the upper and lower layers, so as to meet the inter-cavity coupling of the dielectric resonant cavities of the two filters located in the upper and lower layers respectively. Among them, the shape of the curved waveguide in this embodiment is an arc. As an alternative embodiment, the shape of the curved waveguide can also be any other shape such as a rectangle or a right-angle bend.

[0038] In addition, it should be noted that the curved waveguide itself will also resonate at the appropriate frequency, so the volume of the upper dielectric resonant cavity and the curved waveguide of the common cavity structure should not be too large, and needs to be adjusted to a suitable size according to actual needs.

[0039] like Figure 3 As shown, the lower end of the curved waveguide is connected to the first dielectric resonant cavity of the lower filter through coupling; coupling windows are respectively provided at the coupling connections at the upper and lower ends of the curved waveguide, and the coupling windows can be rectangular windows; by adjusting the size of the rectangular window, the coupling strength of the two dielectric resonant cavities connected by the curved waveguide can be adjusted.

[0040] like Figure 4 , which is a group delay simulation result diagram of the novel common cavity structure provided in this embodiment. In this diagram, the horizontal axis represents frequency in gigahertz and the vertical axis represents group delay in nanoseconds.

[0041] like Figure 5As shown, it is an implementation mode of the dielectric duplexer provided in this embodiment, and the dielectric duplexer adopts the above-mentioned new common cavity structure. Specifically, it includes: the above-mentioned common cavity structure of the upper filter and the lower filter, the upper filter and the lower filter are arranged in upper and lower layers, and are welded as a whole by SMT process, and the curved waveguide of the common cavity structure is welded on one side of the upper filter and the lower filter by SMT process. The upper filter and the lower filter have dielectric resonant cavities respectively. In this embodiment, the shapes of the upper filter and the lower filter are respectively rectangular; however, as an alternative implementation mode, the shapes of the upper filter and the lower filter can also be any shape of a circle, a trapezoid or other polygons. The dielectric duplexer provided in this embodiment can eliminate the mutual coupling of the two filter channels of the dielectric duplexer through the above-mentioned common cavity structure.

[0042] like Figure 6 As shown, the upper filter and the upper dielectric resonant cavity of the common cavity structure are arranged as an integral structure, and the upper dielectric resonant cavity and the first dielectric resonant cavity of the lower filter are coupled and connected via a curved waveguide on the sides thereof.

[0043] like Figure 7 As shown, the upper filter has seven dielectric resonant cavities, and the multiple dielectric resonant cavities are separated by isolation walls, and the isolation walls are strip grooves formed by digging out dielectric blocks. The front faces of the first to sixth dielectric resonant cavities are respectively provided with blind holes; the front face of the seventh dielectric resonant cavity of the upper filter is provided with a tap. Figure 8 As shown, the upper filter has a blind hole on the back side opposite to the tap. The resonant frequency of the dielectric resonant cavity is adjusted by changing the depth of the blind hole on the first to sixth dielectric resonant cavities. The resonant frequency of the dielectric resonant cavity is adjusted on the seventh dielectric resonant cavity by the combination of the blind hole and the tap.

[0044] like Figure 8 As shown, the lower filter has eight dielectric resonant cavities, and the multiple dielectric resonant cavities are separated by isolation walls, and the isolation walls are strip grooves formed by digging out dielectric blocks. The front faces of the first to seventh dielectric resonant cavities are respectively provided with blind holes; the front face of the eighth dielectric resonant cavity of the lower filter is provided with a tap. Figure 7 As shown, the lower filter has a blind hole on the back side opposite to the tap. The resonant frequency of the dielectric resonant cavity is adjusted by changing the depth of the blind hole on the first to seventh dielectric resonant cavities. The resonant frequency of the dielectric resonant cavity is adjusted by the coordination of the blind hole and the tap on the eighth dielectric resonant cavity.

[0045] like Figure 7 , Figure 8As shown, the upper filter and the lower filter are respectively provided with coupling adjustment holes, and the inter-cavity coupling of the corresponding two dielectric resonant cavities can be adjusted by adjusting the structure of the coupling adjustment holes. The first dielectric resonant cavity on the upper filter and the lower filter, which is used to couple with the dielectric resonant cavity of the common cavity structure, is respectively provided with a magnetic field compression through hole; since the first dielectric resonant cavity on the upper filter and the lower filter is greatly affected by the dielectric resonant cavity of the common cavity structure, resulting in the self-resonance frequency being lowered, this problem can be improved by the magnetic field compression through hole.

[0046] like Fig. 9 As shown in FIG. 1 , the electromagnetic simulation results of the dielectric duplexer provided in this embodiment are shown. In this figure, the horizontal axis represents frequency, in gigahertz. The vertical axis represents s parameter. It can be seen that the return loss and insertion loss of the dielectric duplexer are ideal, the isolation is good, and the design index has been met.

[0047] In the above embodiment, the inside of the duplexer is a medium with any dielectric constant, such as a ceramic material; and the outside of the duplexer is a metal conductive layer, which may be a metal electroplating film.

[0048] When in use, the field distribution of the TEM mode is excited in the upper dielectric resonant cavity of the common cavity structure through the metal through-hole, and the TE10 mode is further excited in the dielectric resonant cavity of the two filters connected to the common cavity through the magnetic coupling of the coupling window and the curved waveguide.

[0049] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the present invention.

Claims

1. A dielectric duplexer based on a novel common cavity structure, characterized in that: include: An upper filter, a lower filter and a common cavity structure, wherein the upper filter, the lower filter and the common cavity structure respectively have a dielectric resonant cavity, and the dielectric resonant cavity of the common cavity structure is coupled and connected with the dielectric resonant cavity of the upper filter and the lower filter respectively; A tap feeder structure is provided on the common cavity structure, and the tap feeder structure is composed of a punched metal through hole and an empty groove formed by digging out a dielectric block at the bottom of the metal through hole; The dielectric resonant cavity of the common cavity structure and the dielectric resonant cavity of the lower filter are coupled and connected via a curved waveguide, and coupling windows are respectively provided at the coupling connection points between the two ends of the curved waveguide and the dielectric resonant cavity; The upper filter and the lower filter are both provided with a plurality of dielectric resonant cavities, and the first dielectric resonant cavity on the upper filter and the lower filter, which is used for coupling with the dielectric resonant cavity of the common cavity structure, is respectively provided with a magnetic field compression through hole; At least one coupling debugging hole is respectively provided on the upper filter and the lower filter.

2. The dielectric duplexer based on the novel common cavity structure according to claim 1, characterized in that: The coupling window is rectangular.

3. The dielectric duplexer based on the novel common cavity structure according to claim 1, characterized in that: On the upper filter and the lower filter, each dielectric resonant cavity is respectively provided with a debugging blind hole.

4. The dielectric duplexer based on the novel common cavity structure according to claim 3, characterized in that: On the upper filter and the lower filter, the adjustment blind holes of the last dielectric resonant cavity away from the common cavity structure are respectively located on the opposite surfaces of the upper filter and the lower filter; on the upper filter and the lower filter, taps are respectively provided on the surfaces opposite to the tuning blind holes of the last dielectric resonant cavity.

5. The dielectric duplexer based on a novel common cavity structure according to any one of claims 1 to 4, characterized in that: The plurality of dielectric resonant cavities on the upper filter and the lower filter are separated by a separation wall, and the separation wall is a strip groove formed by digging out a dielectric block.

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