阅读说明：本技术 一种介质滤波器强耦合输入输出结构 (Strong coupling input/output structure of dielectric filter ) 是由 蔡辉 赵虎 戴超 周骑 于 2020-11-18 设计创作，主要内容包括：本发明提供了一种介质滤波器强耦合输入输出结构,其解决了大工作带宽介质滤波器输入输出问题,同时降低生产制造难度。其包括抽头腔,所述抽头腔的上表面设置有一内凹的调频盲孔,所述抽头腔的上表面上还布置有一厚度方向贯穿的耦合通孔,所述调频盲孔不连通所述耦合通孔,所述调频盲孔和耦合通孔之间设置间隔,所述耦合通孔的上表面或下表面设置有和耦合通孔同心的环形凹槽区域、即馈电环,所述抽头腔除去馈电环的区域外、其余表面均覆有导电层,所述抽头腔的材质为陶瓷介质或高分子材料,通过所述馈电环输入或输出电磁波信号。(The invention provides a strong coupling input and output structure of a dielectric filter, which solves the input and output problems of the dielectric filter with large working bandwidth and reduces the production and manufacturing difficulty. The frequency modulation blind hole is arranged on the upper surface of the tap cavity, a coupling through hole penetrating in the thickness direction is further arranged on the upper surface of the tap cavity, the frequency modulation blind hole is not communicated with the coupling through hole, a space is arranged between the frequency modulation blind hole and the coupling through hole, an annular groove area concentric with the coupling through hole, namely a feed ring, is arranged on the upper surface or the lower surface of the coupling through hole, conductive layers are coated on the outer surface and the rest surface of the tap cavity except the outer surface of the feed ring, the tap cavity is made of ceramic media or high polymer materials, and electromagnetic wave signals are input or output through the feed ring.)

1. A kind of medium electric-wave filter strong coupling input-output structure, characterized by that: the frequency modulation blind hole is arranged on the upper surface of the tap cavity, a coupling through hole penetrating in the thickness direction is further arranged on the upper surface of the tap cavity, the frequency modulation blind hole is not communicated with the coupling through hole, a space is arranged between the frequency modulation blind hole and the coupling through hole, an annular groove area concentric with the coupling through hole, namely a feed ring, is arranged on the upper surface or the lower surface of the coupling through hole, conductive layers are coated on the outer surface and the rest surface of the tap cavity except the outer surface of the feed ring, the tap cavity is made of ceramic media or high polymer materials, and electromagnetic wave signals are input or output through the feed ring.

2. A dielectric filter strongly coupled input-output structure as recited in claim 1, wherein: the cross section of the tapping cavity is circular or polygonal.

3. A dielectric filter strongly coupled input-output structure as recited in claim 1, wherein: the conductive layer is specifically a metallic silver layer.

4. A dielectric filter strongly coupled input-output structure as recited in claim 1, wherein: the frequency modulation blind hole is used for adjusting the resonance frequency of the tap cavity, the depth of the frequency modulation blind hole is changed to adjust the resonance frequency of the tap cavity, and the deeper the hole is, the lower the resonance frequency of the tap cavity is, the shallower the hole is, and the higher the resonance frequency of the tap cavity is.

5. A dielectric filter strongly coupled input-output structure as recited in claim 1, wherein: the coupling through hole is a straight-through hole with a constant diameter or a stepped hole with a large diameter and a small diameter.

6. A dielectric filter strongly coupled input-output structure as recited in claim 1, wherein: the spacing distance between the coupling through hole and the frequency modulation blind hole is used for adjusting the input and output coupling size, and the closer the spacing distance is, the stronger the coupling is; the further apart the coupling is, the weaker.

7. A dielectric filter strongly coupled input-output structure as recited in claim 1, wherein: the diameter of the coupling through hole is changed to adjust the inductance characteristic of the coupling through hole, so that the strength of inductive coupling is adjusted; increasing the diameter of the coupling via is used for enhancing the input-output coupling, and decreasing the diameter of the coupling via is used for weakening the input-output coupling.

Technical Field

The invention relates to the technical field of dielectric filters, in particular to a strong coupling input and output structure of a dielectric filter.

Background

With the development of 5G mobile communication technology, miniaturization and integration are becoming the development trends of communication devices. The filter is one of the main functional components of the 5G base station device, and plays a role of selecting electromagnetic waves of a specific frequency. The ceramic dielectric filter is a mainstream technology of the 5G filter due to its small volume, light weight, and easy smt (surface Mount technology) surface mounting. At present, the working bandwidth of a ceramic dielectric filter is about 150 MHz-250 MH, a common input and output structure is a coupling blind hole, as shown in FIG. 1, the principle is that electric field coupling (capacitive coupling) is formed between the coupling blind hole and a frequency modulation blind hole, when the frequency modulation blind hole is not changed, the deeper the coupling blind hole is, the smaller the gap between the coupling blind hole and the frequency modulation blind hole is, the stronger the electric field coupling is, and vice versa, the weaker the electric field coupling is. With the expansion of frequency bands and application ranges, such as a dielectric duplexer and the like, the required working bandwidth is as high as 400-800 MHz, stronger input and output coupling is required, and the gap between a coupling blind hole and a frequency modulation blind hole is too small, so that hole breaking and production difficulty are easily caused.

Disclosure of Invention

Aiming at the problems, the invention provides a strong coupling input-output structure of a dielectric filter, which solves the input-output problem of the dielectric filter with large working bandwidth and reduces the production and manufacturing difficulty.

A kind of medium electric-wave filter strong coupling input-output structure, characterized by that: the frequency modulation blind hole is arranged on the upper surface of the tap cavity, a coupling through hole penetrating in the thickness direction is further arranged on the upper surface of the tap cavity, the frequency modulation blind hole is not communicated with the coupling through hole, a space is arranged between the frequency modulation blind hole and the coupling through hole, an annular groove area concentric with the coupling through hole, namely a feed ring, is arranged on the upper surface or the lower surface of the coupling through hole, conductive layers are coated on the outer surface and the rest surface of the tap cavity except the outer surface of the feed ring, the tap cavity is made of ceramic media or high polymer materials, and electromagnetic wave signals are input or output through the feed ring.

It is further characterized in that:

the cross section of the tapping cavity is circular or polygonal;

the conducting layer is specifically a metal silver layer;

the frequency modulation blind hole is used for adjusting the resonance frequency of the tap cavity, the depth of the frequency modulation blind hole is changed to adjust the resonance frequency of the tap cavity, and the deeper the hole depth is, the lower the resonance frequency of the tap cavity is, the shallower the hole depth is, and the higher the resonance frequency of the tap cavity is;

the coupling through hole is a straight through hole with a constant diameter or a stepped hole with a large diameter and a small diameter;

the spacing distance between the coupling through hole and the frequency modulation blind hole is used for adjusting the input and output coupling size, and the closer the spacing distance is, the stronger the coupling is; the farther apart, the weaker the coupling;

the diameter of the coupling through hole is changed to adjust the inductance characteristic of the coupling through hole, so that the strength of inductive coupling is adjusted; increasing the diameter of the coupling via is used for enhancing the input-output coupling, and decreasing the diameter of the coupling via is used for weakening the input-output coupling.

After the invention is adopted, because the coupling hole is a through hole, the inner surface of the coupling hole covered with the conductive metal layer is connected with the outer surface of the tap cavity covered with the conductive layer, external signal excitation current flows to the outer surface of the tap cavity through the coupling hole to realize grounding, an excitation magnetic field surrounding the coupling hole is generated around the coupling hole, and the excitation magnetic field is coupled with a resonance magnetic field surrounding the frequency modulation blind hole (inductive coupling) to realize input or output excitation, and because the excitation magnetic field and the resonance magnetic field are respectively concentrated near the coupling hole and the frequency modulation blind hole, strong coupling can be generated only by slightly approaching the two holes; the distance between the coupling through hole and the frequency modulation blind hole is reduced, so that the input and output coupling can be enhanced, and the input and output coupling is weakened on the contrary; meanwhile, the inductive characteristic can be effectively adjusted by changing the diameter of the coupling through hole, so that the strength of inductive coupling is adjusted; the diameter of the coupling through hole is increased to enhance input-output coupling, otherwise, the input-output coupling is weakened, the through hole is easy to process, and the risk of hole breakage is not considered; therefore, the input and output problems of the medium filter with large working bandwidth are solved, and the production and manufacturing difficulty is reduced.

Drawings

Fig. 1 is a prior art input-output coupling structure of a dielectric filter;

FIG. 2 is a schematic structural view of the present invention;

fig. 3 is a schematic structural diagram of a dielectric duplexer applied in the present invention;

fig. 4 is a frequency response curve of the dielectric duplexer of fig. 3;

the names corresponding to the sequence numbers in the figure are as follows:

tap cavity 1, frequency modulation blind hole 2, coupling through hole 3 and feed ring 4

A dielectric duplexer 100, an RX receiving port 5, a TX transmitting port 6, an ANT antenna port 7 and a coupling slot 8.

Detailed Description

A dielectric filter strong coupling input-output structure, see fig. 2: the frequency modulation blind hole coupling structure comprises a tap cavity 1, wherein an inwards concave frequency modulation blind hole 2 is formed in the upper surface of the tap cavity 1, a coupling through hole 3 penetrating in the thickness direction is further formed in the upper surface of the tap cavity 1, the frequency modulation blind hole 2 is not communicated with the coupling through hole 3, a gap is formed between the frequency modulation blind hole 2 and the coupling through hole 3, an annular groove region concentric with the coupling through hole 3, namely a feed ring 4, is formed in the upper surface or the lower surface of the coupling through hole 3, conducting layers (not shown in the figure and belonging to the existing mature structure) cover the outer region and the rest surfaces of the tap cavity 1 except the feed ring 4, the tap cavity 1 is made of ceramic medium or high polymer materials, and electromagnetic wave signals are input or output through the feed ring.

The cross section of the tapping cavity 1 is circular or polygonal;

the conductive layer is a metal silver layer;

the frequency modulation blind hole 2 is used for adjusting the resonance frequency of the tap cavity, the depth of the frequency modulation blind hole 2 is changed to adjust the resonance frequency of the tap cavity 1, and the deeper the hole depth is, the lower the resonance frequency of the tap cavity 1 is, the shallower the hole depth is, and the higher the resonance frequency of the tap cavity 1 is;

the coupling through hole 3 is a straight through hole with a constant diameter or a stepped hole with a large diameter and a small diameter;

the spacing distance between the coupling through hole 3 and the frequency modulation blind hole 2 is used for adjusting the input and output coupling, and the closer the spacing distance is, the stronger the coupling is; the farther apart, the weaker the coupling;

the diameter of the coupling through hole 3 is changed to adjust the inductance characteristic of the coupling through hole, so that the strength of inductive coupling is adjusted; increasing the diameter of the coupling via 3 is used for enhancing the input-output coupling, and decreasing the diameter of the coupling via 3 is used for weakening the input-output coupling.

In the first embodiment, see fig. 3, which is a dielectric duplexer 100 applying the input/output structure, the dielectric duplexer includes a ceramic dielectric substrate (tap cavity 1), a frequency blind hole (frequency modulation blind hole 2) located on an upper surface of the substrate, an RX receiving port 5, a TX transmitting port 6, an ANT antenna port 7, and a coupling isolation groove 8 penetrating through the substrate, and a conductive metal layer is coated on a surface of the dielectric substrate, an inner surface of the frequency blind hole, and a side surface of the coupling isolation groove. The medium duplexer works in 1805-1880/2110-2170MHz band, its ANT port needs to cover 1805-2170MHz band and 365MHz band, if the existing blind hole input/output structure is adopted, the gap between the coupling blind hole and the frequency modulation blind hole is less than 0.5mm, and the hole breakage is easy to occur. Therefore, the ANT port input-output structure of the dielectric duplexer adopts the structure provided by the invention, and the TX and RX ports are provided with a coupling through hole 3 and a feed ring 4 due to the narrower working bandwidth. Fig. 4 is a frequency response curve of the dielectric duplexer. As can be seen from the figure, the return loss S11 of the dielectric duplexer reaches-23 dB in the working frequency band, so that the strong coupling input-output structure provided by the invention realizes effective excitation.

After the structure is adopted, because the coupling hole is a through hole, the inner surface of the coupling hole covered with the conductive metal layer is connected with the outer surface of the tap cavity covered with the conductive layer, external signal excitation current flows to the outer surface of the tap cavity through the coupling through hole to realize grounding, an excitation magnetic field surrounding the coupling through hole is generated around the coupling through hole, and the excitation magnetic field is coupled with a resonance magnetic field surrounding the frequency modulation blind hole (inductive coupling) to realize input or output excitation, and because the excitation magnetic field and the resonance magnetic field are respectively concentrated near the coupling through hole and the frequency modulation blind hole, strong coupling can be generated only by slightly approaching the two holes; the distance between the coupling through hole and the frequency modulation blind hole is reduced, so that the input and output coupling can be enhanced, and the input and output coupling is weakened on the contrary; meanwhile, the inductive characteristic can be effectively adjusted by changing the diameter of the coupling through hole, so that the strength of inductive coupling is adjusted; the diameter of the coupling through hole is increased to enhance input-output coupling, otherwise, the input-output coupling is weakened, the through hole is easy to process, and the risk of hole breakage is not considered; therefore, the input and output problems of the medium filter with large working bandwidth are solved, and the production and manufacturing difficulty is reduced.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.