CN111384518A - Dielectric filter, communication equipment, method for preparing dielectric block and dielectric filter - Google Patents

Abstract

The application discloses a dielectric filter, communication equipment, a dielectric block and a method for manufacturing the dielectric filter. The dielectric filter includes: a first dielectric resonator including at least a first dielectric block; a second dielectric resonator including at least a second dielectric block; the dielectric coupling plate is arranged between the first dielectric block and the second dielectric block and connected with the first dielectric block and the second dielectric block, and the dielectric coupling plate is used for realizing the coupling between the first dielectric resonator and the second dielectric resonator; wherein, the material of the dielectric filter at least comprises strontium carbonate, samarium oxide, aluminum oxide and titanium dioxide. The embodiment of the application can improve the electromagnetic signal coupling effect of the dielectric filter, reduce interference and optimize the performance of the dielectric filter; and the dielectric filter of the embodiment of the application has improved microwave dielectric property.

Description

Dielectric filter, communication equipment, method for preparing dielectric block and dielectric filter

Technical Field

The present application relates to the field of communications technologies, and in particular, to a dielectric filter applied to a 5G communications system, a communications device, a method for manufacturing a dielectric block, and a method for manufacturing a dielectric filter.

Background

With the rapid advance of communication technology, especially in the coming 5G communication era, more rigorous technical requirements are put on system architecture, and while high-efficiency and high-capacity communication is realized, system modules are required to be highly integrated, miniaturized, light-weighted and low-cost. For example, when the 5G Massive MIMO technology further expands the system channel from the current 8 or 16 channels to 32, 64, or even 128 channels, the overall architecture size of the system cannot be too large, and even a certain degree of miniaturization needs to be realized. The microwave filter is used as a core component of a system, and performance parameters, size and cost of the microwave filter have great influence on the performance, architecture size and cost of the system.

The inventor of the present application has found in long-term research and development work that a dielectric filter is composed of a plurality of dielectric resonators, has the characteristics of miniaturization and high performance, and receives more and more attention. In order to realize coupling between dielectric resonators arranged adjacently, a window (i.e., a part which is not metalized and exposes a dielectric body) is formed on the surface of each dielectric resonator by a process of coating silver on a steel mesh and the like when the surface of each dielectric resonator is metalized, and coupling between the dielectric resonators arranged adjacently is realized through the window.

Disclosure of Invention

The technical problem mainly solved by the present application is to provide a dielectric filter, a communication device, a method for preparing a dielectric block and a dielectric filter, so as to solve the above problems.

In order to solve the technical problem, the present application adopts a technical scheme that: there is provided a dielectric filter including: a first dielectric resonator including at least a first dielectric block; a second dielectric resonator including at least a second dielectric block; the dielectric coupling plate is arranged between the first dielectric block and the second dielectric block and connected with the first dielectric block and the second dielectric block, and the dielectric coupling plate is used for realizing the coupling between the first dielectric resonator and the second dielectric resonator; wherein, the material of the dielectric filter at least comprises strontium carbonate, samarium oxide, aluminum oxide and titanium dioxide.

In order to solve the technical problem, the present application adopts a technical scheme that: there is provided a method for preparing a dielectric block, the method being used for preparing the first dielectric block, the second dielectric block or the dielectric coupling plate, the method comprising: providing raw materials of strontium carbonate, samarium oxide, aluminum oxide and titanium dioxide; adding an organic solvent and grinding balls and carrying out primary ball milling; drying the slurry obtained by the primary ball milling, and calcining to obtain a ceramic body; crushing the ceramic body, adding an organic solvent and grinding balls, and performing secondary ball milling; drying the slurry obtained by secondary ball milling; mixing the obtained powder with a binder to form slurry, and granulating; dry-pressing and molding in a mold matched with the shape of the first dielectric block, the second dielectric block or the dielectric coupling plate; and removing the binder and sintering again to obtain the first dielectric block, the second dielectric block or the dielectric coupling plate.

In order to solve the technical problem, the present application adopts a technical scheme that: there is provided a method for manufacturing a dielectric filter, the method being used for manufacturing the above dielectric filter, the method comprising: providing a first dielectric block, a second dielectric block and a dielectric coupling plate, wherein the first dielectric block, the second dielectric block and the dielectric coupling plate are all prepared by the method; and covering metal layers on the surfaces of the first dielectric block, the second dielectric block and the dielectric coupling plate to obtain the dielectric filter.

In order to solve the technical problem, the present application adopts a technical scheme that: the communication device comprises the dielectric filter and the antenna, wherein the dielectric filter is coupled with the antenna, and the dielectric filter is used for filtering the transceiving signals of the antenna.

The beneficial effect of this application is: different from the prior art, the dielectric filter of the embodiment of the present application at least includes: a first dielectric resonator including a first dielectric block; a second dielectric resonator including a second dielectric block; the dielectric coupling plate is arranged between the first dielectric block and the second dielectric coupling plate and connected with the first dielectric block and the second dielectric block, and the dielectric coupling plate is used for realizing the coupling between the first dielectric resonator and the second dielectric resonator; wherein, the material of the dielectric filter at least comprises strontium carbonate, samarium oxide, aluminum oxide and titanium dioxide. According to the embodiment of the application, the dielectric coupling plate is arranged between the first dielectric resonator and the second dielectric resonator to realize the coupling between the first dielectric resonator and the second dielectric resonator, and the problem of poor coupling effect through an air window in the prior art can be solved because the dielectric constants of the dielectric coupling plate and the dielectric blocks of the resonators are the same or similar, so that the electromagnetic signal coupling effect of the dielectric filter can be improved, the interference is reduced, and the performance of the dielectric filter can be optimized; in addition, the material of the dielectric filter mainly comprises strontium carbonate, samarium oxide, aluminum oxide and titanium dioxide, and has low dielectric constant, low loss and near-zero temperature coefficient. Therefore, the dielectric filter of the embodiment of the application has improved microwave dielectric performance.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

FIG. 1 is a schematic structural diagram of a first embodiment of a dielectric filter according to the present application;

FIG. 2 is a schematic cross-sectional view AA of the dielectric filter of the embodiment of FIG. 1;

FIG. 3 is a schematic structural diagram of a second embodiment of a dielectric filter according to the present application;

FIG. 4 is a schematic cross-sectional view of the dielectric filter of the embodiment of FIG. 3 taken along BB;

FIG. 5 is a schematic structural diagram of a third embodiment of a dielectric filter according to the present application;

fig. 6 is a schematic structural diagram of a dielectric coupling plate in the dielectric filter of the embodiment of fig. 5;

fig. 7 is a schematic structural diagram of a second embodiment of a dielectric coupling plate in a dielectric filter according to the present application;

figure 8 is a schematic structural view of a third embodiment of a dielectric coupling plate in a dielectric filter according to the present application;

figure 9 is a schematic structural view of a fourth embodiment of a dielectric coupling plate for use in a dielectric filter according to the present application;

FIG. 10 is a schematic diagram of a fourth embodiment of a dielectric filter according to the present application;

FIG. 11 is a schematic flow chart diagram illustrating one embodiment of a method for forming a dielectric block according to the present application;

FIG. 12 is a schematic flow chart diagram illustrating one embodiment of a method for making a dielectric filter according to the present application;

FIG. 13 is a block diagram of an embodiment of a communication device of the present application;

fig. 14 shows the results of the test of the microwave dielectric properties of the material of the dielectric filter of the present application.

Detailed Description

The present application will be described in further detail with reference to the following drawings and examples. It is to be noted that the following examples are only illustrative of the present application, and do not limit the scope of the present application. Likewise, the following examples are only some examples and not all examples of the present application, and all other examples obtained by a person of ordinary skill in the art without any inventive step are within the scope of the present application.

The terms "first," "second," "third," "fourth," and the like in the description and in the claims of the present application and in the drawings described above, if any, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the application described herein are, for example, capable of operation in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

The dielectric filter and the communication equipment can be used for a 5G communication system.

The dielectric filter is prepared by filling the resonant cavity with materials such as ceramics with high dielectric constants and the like, so that a microwave wavelength compression effect can be generated, the effective size of the resonant cavity can be greatly compressed, the overall size of the dielectric filter is miniaturized, and meanwhile, the materials such as ceramics are easy to mold, and batch production with lower cost can be realized, so that the dielectric filter is highly matched with the technical requirements of 5G micro base stations (Small Cells) and MIMO systems, and higher attention and market application of related communication scenes are obtained.

First, a dielectric filter is proposed, as shown in fig. 1 and fig. 2, fig. 1 is a schematic structural diagram of a first embodiment of the dielectric filter; figure 2 is a schematic cross-sectional view AA of the dielectric filter of the embodiment of figure 1. Thedielectric filter 101 of the present embodiment includes: the dielectric coupling plate comprises a firstdielectric resonator 102, a seconddielectric resonator 103 and adielectric coupling plate 104, wherein the firstdielectric resonator 102 at least comprises a firstdielectric block 105, and the seconddielectric resonator 103 at least comprises a seconddielectric block 106; thedielectric coupling plate 104 is disposed between the firstdielectric block 105 and the seconddielectric block 106, and is connected to the firstdielectric block 105 and the seconddielectric block 106, and thedielectric coupling plate 104 is used for realizing coupling between the firstdielectric resonator 102 and the seconddielectric resonator 103.

In this embodiment, the firstdielectric block 105, the seconddielectric block 106 and thedielectric coupling plate 104 may be made of the same dielectric material, which may be a ceramic material. In other embodiments, the materials of the dielectric block and the dielectric coupling plate may also be other materials with high dielectric constant and low loss, such as glass, quartz crystal, or titanate, and it is not limited whether the materials of the dielectric block and the dielectric coupling plate are the same.

Different from the prior art, the firstdielectric resonator 102 and the seconddielectric resonator 103 of the embodiment are coupled by thedielectric coupling plate 104, and compared with the conventional air window, because the dielectric constants of the dielectric coupling plate and the dielectric blocks of the resonators are the same or similar, the problem of poor coupling effect through the air window can be improved, and therefore, the electromagnetic signal coupling effect of thedielectric filter 101 can be improved, interference can be reduced, and the performance can be optimized.

Optionally, the firstdielectric resonator 102 of this embodiment further includes afirst metal layer 107 covering the surface of the firstdielectric block 105, and the seconddielectric resonator 103 further includes asecond metal layer 108 covering the surface of the seconddielectric block 106; thefirst metal layer 107 defines afirst opening 201, thesecond metal layer 108 defines asecond opening 202, thefirst opening 201 and the second opening 202 form a window, and thedielectric coupling plate 104 is disposed in the window.

The material of the metal layer may be silver, copper, aluminum, titanium, tin, gold, or the like.

In this embodiment, a specific mold may be used to form the firstdielectric block 105, the seconddielectric block 106, and thedielectric coupling plate 104, and then thefirst metal layer 107 is covered on the surface of the firstdielectric block 105 and thesecond metal layer 108 is covered on the surface of the seconddielectric block 106 by electroplating, spraying or welding.

In this embodiment, a steel-mesh-silver process can be used to form thefirst opening 201 on thefirst metal layer 107 and thesecond opening 202 on thesecond metal layer 108.

Thefirst metal layer 105 serves to confine an electromagnetic field within the firstdielectric block 105, and can prevent leakage of an electromagnetic signal to form a standing wave oscillation signal within the firstdielectric block 105; thesecond metal layer 108 serves to confine an electromagnetic field within the seconddielectric block 106, and can prevent leakage of an electromagnetic signal to form a standing wave oscillation signal within the seconddielectric block 106.

The thickness of thedielectric coupling plate 104 of this embodiment is equal to or slightly greater than the sum of the thickness of thefirst metal layer 107 and the thickness of thesecond metal layer 108, so that when thedielectric coupling plate 104 is filled in the window formed by thefirst opening 201 and thesecond opening 202, thedielectric coupling plate 104 is connected to the firstdielectric block 105 and the seconddielectric block 106 respectively; thefirst metal layer 107 and thesecond metal layer 108 located on the periphery of thedielectric coupling plate 104 may be connected and fixed by a soldering process to connect and fix the firstdielectric resonator 102 and the seconddielectric resonator 103. Of course, in other embodiments, the first dielectric resonator and the second dielectric resonator may be fixed by other processes, such as connecting with conductive adhesive, or clamping with other clamps.

In another embodiment, as shown in fig. 3 and 4, fig. 3 is a schematic structural diagram of a second embodiment of the dielectric filter of the present application; fig. 4 is a schematic cross-sectional view of the dielectric filter of the embodiment of fig. 3 along BB. Thedielectric filter 301 of the present embodiment is different from thedielectric filter 101 described above in that: in the present embodiment, the thickness of thedielectric coupling plate 302 is larger than the sum of the thickness of thefirst metal layer 303 and the thickness of thesecond metal layer 304, and in the present embodiment, after thedielectric coupling plate 302 is connected to the firstdielectric block 305 and the seconddielectric block 306, the surface of thedielectric coupling plate 302 is further covered with themetal layer 307, and then themetal layer 307 is connected to thefirst metal layer 303 and thesecond metal layer 304 by a welding process.

Themetal layer 307 serves to confine the electromagnetic field within thedielectric coupling plate 302, and can prevent leakage of the electromagnetic signal to form a standing wave oscillation signal within thedielectric coupling plate 302.

In the above-mentioned steel mesh silver-coated process for forming the window and the process for splicing the dielectric block and the dielectric coupling plate, there are problems of inaccurate positioning, secondary sintering, etc. in order to solve the above-mentioned problems, the present application further provides a dielectric filter of a third embodiment, as shown in fig. 5, a difference between thedielectric filter 501 of this embodiment and the above-mentioned dielectric filter is: thedielectric coupling plate 502, the firstdielectric block 503 and the seconddielectric block 504 of the present embodiment are formed by one-step sintering.

Specifically, in this embodiment, a specific mold may be used to form thedielectric coupling plate 502, the firstdielectric block 503 and the seconddielectric block 504, and thedielectric coupling plate 502, the firstdielectric block 503 and the seconddielectric block 504 are once sintered and molded, and then the sintered and moldeddielectric coupling plate 502, the firstdielectric block 503 and the seconddielectric block 504 are covered with themetal layer 505.

Of course, in other embodiments, after the dielectric body is formed, a groove may be formed on the dielectric body by grooving or etching, so as to form the dielectric block and the dielectric coupling plate by spacing the dielectric body through the groove, and then the dielectric block and the dielectric coupling plate are formed by one-step sintering.

Different from the prior art, thedielectric coupling plate 502, the firstdielectric block 503 and the seconddielectric block 504 of the present embodiment are integrally formed by sintering, so that the disadvantages caused by complicated and tedious processes such as steel mesh silver coating, high-precision positioning and splicing of a clamp, secondary high sintering and the like in the existing dielectric filter sintering process can be overcome, the production efficiency can be improved, the cost can be saved, and the mass production can be facilitated.

Thedielectric coupling plate 502 of the present embodiment is disposed in the gap between the firstdielectric block 503 and the seconddielectric block 504. Specifically, thedielectric coupling plate 502 is disposed near a side of the gap. Of course, in other embodiments, the dielectric coupling plate may also be disposed at the middle of the gap, and may also be moved up, down, left, or right according to the actual situation.

In this embodiment, the firstdielectric block 503 and the seconddielectric block 504 are cubic. The cubic shape can simplify the process and facilitate the processing and combination. Of course, in other embodiments, the first dielectric block and the second dielectric block may have other common shapes, such as a cylinder, a trapezoid, etc.

Optionally, the surface of the firstdielectric block 503 of this embodiment is further provided with afirst adjusting member 506, and the first adjustingmember 506 is ablind hole 506, and ametal layer 505 is covered inside theblind hole 506 to prevent the electromagnetic signal from leaking out of theblind hole 506. The resonant frequency of the first dielectric resonator corresponding to the firstdielectric block 503 can be adjusted by polishing or thickening themetal layer 505 in the blind via 506, so that the resonant frequency of thedielectric filter 501 can be adjusted.

The surface of the seconddielectric block 504 of the present embodiment is further provided with asecond adjusting member 507, and thesecond adjusting member 507 is ablind hole 507, and is covered with ametal layer 505 to prevent the electromagnetic signal from leaking from theblind hole 507. The resonant frequency of the second dielectric resonator corresponding to the seconddielectric block 504 can be adjusted by polishing or thickening themetal layer 505 in the blind via 507, so that the resonant frequency of thedielectric filter 501 can be adjusted.

In another embodiment, an adjusting screw rod can be arranged in the blind hole, and the resonant frequency of the dielectric resonator and the dielectric filter can be adjusted by adjusting the depth of the adjusting screw rod in the blind hole. And no metal layer is arranged in the blind hole, or the metal layer is arranged at one end of the blind hole close to the surface of the dielectric block, and the metal layer is not arranged at the other end of the blind hole, so that the method is not limited.

Furthermore, in order to improve the adjustment precision of the resonant frequency, a plurality of blind holes can be arranged on one dielectric body, and the size data of each blind hole is different.

The surface of thedielectric coupling plate 502 of this embodiment is further provided with athird adjusting part 508, and thethird adjusting part 508 is acoupling hole 508, so as to adjust the coupling strength between the first dielectric resonator and the second dielectric resonator, or to implement cross coupling between the first dielectric resonator and the second dielectric resonator, to implement transmission zero, and to adjust the out-of-band rejection of the dielectric filter. Of course, in other embodiments, an adjusting screw may be disposed in the coupling hole, similar to the adjusting screw described above, and is not described herein again.

It should be noted that, in the embodiment of the present application, the number of dielectric resonators in a dielectric filter, the number of blind holes on the same dielectric resonator, and the number of coupling holes on a dielectric coupling plate are not limited, and whether the number of blind holes on different dielectric resonators is the same or not, and whether the number of coupling holes on different dielectric coupling plates is the same or not, are not limited.

The dielectric coupling plate of the embodiment of the application can be transversely or longitudinally arranged between the first dielectric block and the second dielectric block.

Thedielectric coupling plate 502 of this embodiment is square to realize positive coupling between the first dielectric resonator and the second dielectric resonator. Of course, the structural style of the dielectric coupling plate can also be set according to actual needs, for example: the same or similar structure as the dielectric coupling plate described below is provided.

In other embodiments, to achieve negative coupling between the first dielectric resonator and the second dielectric resonator, the extension length of the dielectric coupling plate in a plane parallel to the gap between the first dielectric block and the second dielectric block is greater than half the wavelength of the operating frequency of the dielectric filter, for reversing the polarity of coupling between the first dielectric resonator corresponding to the first dielectric block and the second dielectric resonator corresponding to the second dielectric block.

Specifically, the dielectric coupling plate of the embodiment of the present application at least includes: the medium comprises a first medium part and a second medium part, wherein the second medium part extends from the end part of the first medium part, and the first medium part and the second medium part form an angle range of 0-90 degrees with each other.

In an embodiment, as shown in fig. 6, fig. 6 is a schematic structural diagram of a dielectric coupling plate in the dielectric filter of the embodiment of fig. 5. The cross-sectional shape of thedielectric coupling plate 502 parallel to the gap between the firstdielectric block 503 and the seconddielectric block 504 is arcuate. Specifically, thedielectric coupling plate 502 of the present embodiment further includes a firstdielectric portion 601, a seconddielectric portion 602 extending from an end of the firstdielectric portion 601, a thirddielectric portion 603 extending from an end of the seconddielectric portion 602, a fourthdielectric portion 604 extending from an end of the thirddielectric portion 603, and a dielectric pattern formed by a limited number of cycles connected in sequence by a connection sequence of repeated cycles of the firstdielectric portion 601, the seconddielectric portion 602, the thirddielectric portion 603, and the fourthdielectric portion 604. Specifically, thedielectric coupling plate 502 of the present embodiment includes: the combination of the two sets of medium patterns in the above-described entire circulation order and the one set of window patterns in the partial circulation order lacking the fourthmedium portion 604, forms medium patterns in which the firstmedium portion 601, the secondmedium portion 602, the third medium portion 6034, the fourthmedium portion 604, the firstmedium portion 601, the secondmedium portion 602, the thirdmedium portion 603, the fourthmedium portion 604, the firstmedium portion 601, the secondmedium portion 602, and the thirdmedium portion 603 are connected in order.

In the present embodiment, the widths of the firstmedium section 601, the secondmedium section 602, the thirdmedium section 603, and the fourthmedium section 604 may be the same or different. Wherein, two connected medium parts are set to be vertical, and the like is performed, and finally, the medium pattern in an arc shape is formed.

The sum of the lengths of all dielectric parts in the arched dielectric patterns is larger than the half wavelength of the working frequency of the dielectric filter, so that the coupling polarity between the first dielectric resonator and the second dielectric resonator is reversed, negative coupling is generated, a transmission zero point is realized, and the out-of-band rejection performance and other performances are improved.

The plurality of medium portions may be formed by sintering after being formed by a mold, or may be formed by splicing a plurality of medium portions and then sintering after being formed, which is not particularly limited.

It is understood that the wider the width of the dielectric portion is set, the stronger the negative coupling strength between the first dielectric resonator and the second dielectric resonator. Of course, the widths of the different dielectric portions may be different, so that the coupling polarity between the first dielectric resonator and the second dielectric resonator can be reversed without affecting the essence that the total length of the dielectric portion having the overall arch-shaped dielectric portion structure exceeds the half-wavelength scheme.

Further, an input port is arranged on the first dielectric resonator and used for inputting radio frequency energy; an output port is provided on the second dielectric resonator for transmitting the radio frequency energy.

In summary, the scheme of reversing the coupling polarity is simpler in structure by changing the structural form of the dielectric coupling plate, the coupling strength can be controlled by the change of the length and the line width of each dielectric part, the productivity is high, and the cost is lower.

In another embodiment, as shown in fig. 7, thedielectric coupling plate 701 includes a firstdielectric portion 702 and a seconddielectric portion 703, the extending direction of the firstdielectric portion 702 may form any angle with the upper and lower surfaces of the dielectric block, the seconddielectric portion 703 is connected to the end of the firstdielectric portion 702, the firstdielectric portion 702 and the seconddielectric portion 703 form an angle with each other in a range of (0, 90 °), the angle may be 15 °, 30 °, 45 ° or 60 °, and the like, so that thedielectric coupling plate 701 forms a V shape.

In another embodiment, the extending direction of the first dielectric part may be perpendicular to the upper and lower surfaces of the dielectric block, the second dielectric part is connected to the end of the first dielectric part, and the first dielectric part and the second dielectric part form an angle of 90 ° with each other, so that the dielectric coupling plate is L-shaped.

In another embodiment, the dielectric coupling plate may also be formed by connecting a plurality ofdielectric coupling plates 701 end to end, so that the dielectric coupling plate is W-shaped.

In another embodiment, as shown in fig. 8, thedielectric coupling plate 801 includes a firstdielectric portion 802 and a seconddielectric portion 803, the extending direction of the firstdielectric portion 802 is parallel to the upper and lower surfaces of the dielectric block, the seconddielectric portion 803 extends from the middle of the firstdielectric portion 802, and the firstdielectric portion 802 and the seconddielectric portion 803 form an angle of 90 ° with each other, so that thedielectric coupling plate 801 is T-shaped.

In another embodiment, as shown in fig. 9, thedielectric coupling plate 901 may only include the firstdielectric portion 902, and the firstdielectric portion 902 is disposed in an arc shape, such as a C shape.

In other embodiments, the dielectric coupling plate may have other shapes, such as U-shape, N-shape, etc., which are not described herein.

The dielectric coupling plate of the embodiment of the present application may include one, two, or more than two dielectric portions to form various shapes.

The present application further proposes a dielectric filter of a fourth embodiment, and as shown in fig. 10, adielectric filter 1001 of the present embodiment is different from the above-described dielectric filter in that: thefirst dielectric resonator 1002 and thesecond dielectric resonator 1003 of this embodiment are both multimode dielectric resonators, and thedielectric coupling plate 1004 is rotatably connected to the first dielectric block of thefirst dielectric resonator 1002 and/or the second dielectric block of thesecond dielectric resonator 1003, and is used to adjust a resonance mode between thefirst dielectric resonator 1002 and thesecond dielectric resonator 1003.

Further, thedielectric filter 1001 further includes adielectric shaft 1005, and thefirst dielectric resonator 1002 and thesecond dielectric resonator 1003 may be rotatably connected to thedielectric coupling plate 1004 via thedielectric shaft 1005.

When thefirst dielectric resonator 1002 or thesecond dielectric resonator 1003 is rotated with respect to thedielectric coupling plate 1004, the three-dimensional size of thedielectric coupling plate 1004 with respect to thefirst dielectric resonator 1002 or thesecond dielectric resonator 1003 can be changed, and thus the resonance mode transmitted through thedielectric coupling plate 1004 can be adjusted.

Unlike the prior art, the present embodiment can adjust the three-dimensional size of thedielectric coupling plate 1004 with respect to thefirst dielectric resonator 1002 and/or with respect to thesecond dielectric resonator 1003 to adjust the resonance mode of thefirst dielectric resonator 1002 and thesecond dielectric resonator 1003 transmitted through thedielectric coupling plate 1004. Therefore, the resonance mode output from thedielectric filter 1001 can be increased, the frequency band can be widened, and the application range can be widened.

The material of the dielectric filter disclosed in the above embodiment may be ceramic, and the ceramic includes strontium carbonate, samarium oxide, aluminum oxide, and titanium dioxide. I.e., the ceramic consists essentially of the above-described components, it is understood that the ceramic may also contain small or trace amounts of other substances.

In some embodiments, the strontium carbonate is present in an amount of 48 to 62 mole percent.

In some embodiments, the samarium trioxide is present in an amount ranging from 10% to 24% by mole.

In some embodiments, the alumina is present in a mole percent of 10% to 24%.

In some embodiments, the titanium dioxide comprises between 4% and 18% by mole.

Wherein, mole percent refers to the percentage of the amount of the substance. For example, after mixing 1mol of substance a with 4mol of substance B, the molar percentage of substance a is equal to 1/(1+4) 20%, while the molar percentage of substance B is equal to 4/(1+4) 80%.

The chemical composition of the ceramic may be expressed as aSrCO₃-bSm₂O₃-cAl₂O₃-dTiO₂Wherein the ratio of a, b, c and d is 0.48-0.62: 0.1-0.24: 0.04-0.18. For example, if the values of a, b, c, and d are taken as 0.5, 0.2, and 0.1, respectively, the chemical composition of the ceramic may be expressed as 0.5SrCO₃-0.2Sm₂O₃-0.2Al₂O₃-0.1TiO₂. Of course, the values of a, b, c and d may take other values within this range. The microwave dielectric properties of the ceramic can be further adjusted by varying the proportions between the chemical components of the ceramic.

In some embodiments, the ceramic may further include a modifying additive, i.e., an additive capable of improving the properties of the ceramic. It should be understood that the modifying additive need not be in a liquid form, but may be in a solid form, etc. In particular, the modifying additive may be Ta₂O₅、Bi₂O₃Or SiO₂That is, the modifying additive may comprise only Ta₂O₅、Bi₂O₃Or SiO₂May also include two or three of them. Alternatively, the proportion of the modifying additive may be 0.01 mol% to 1 mol%. That isIn other words, the percentage of the modifying additive to the mole number of the whole material is 0.01-1%.

According to the test result, the dielectric constant of the ceramic is 18 to 22, the Q f value is 43000 to 76000GHz, and the temperature coefficient is-11 to +23 ppm/DEG C. For example, the microwave dielectric property of the ceramic is tested by a network analyzer (Agilent 5071C) at a test frequency of 6.5GHz, and the microwave dielectric property of the ceramic is obtained as follows: the dielectric constant r is 18 to 22, the dielectric loss Q f is 43000 to 76000GHz, and the temperature coefficient f is-11 to +23 ppm/DEG C. Fig. 14 exemplarily shows the test results of the microwave dielectric properties of the ceramics provided herein.

The ceramic mainly comprises strontium carbonate, samarium oxide, aluminum oxide and titanium dioxide, and has low dielectric constant, low loss and near-zero temperature coefficient. Thus, the ceramics provided by the practice of the present application have improved microwave dielectric properties.

The present application further provides a method for manufacturing a dielectric block, in which the first dielectric block, the second dielectric block and the dielectric coupling plate disclosed in the above embodiments are all manufactured by the method for manufacturing a dielectric block, as shown in fig. 11, the method includes the following steps:

s1101: raw materials corresponding to strontium carbonate, samarium sesquioxide, aluminum oxide and titanium dioxide are provided.

In some embodiments, the raw materials corresponding to strontium carbonate, samarium trioxide, aluminum oxide, and titanium dioxide may be oxides or carbonates of the corresponding metal elements. Wherein the oxides of the metal elements directly correspond to the components of the ceramic to be produced, and some of the carbonates of the metal elements can be converted into the oxides of the metal elements under heat or the like, and thus can also be used as raw materials. In other embodiments, the starting material may also be an alcoholate of the corresponding metal element, in which case the alcoholate of the metal may be converted to the desired oxide using a suitable chemical treatment. The specific method is well known in the art and will not be described herein.

In this embodiment, the molar percentage of the raw material corresponding to strontium carbonate is 48% to 62%, the molar percentage of the raw material corresponding to samarium oxide is 10% to 24%, the molar percentage of the raw material corresponding to aluminum oxide is 10% to 24%, and the molar percentage of the raw material corresponding to titanium dioxide is 4% to 18%. It should be understood that the above mole percentages refer to mole percentages after removal of impurities in the raw materials.

In this example, raw materials were prepared in accordance with the proportions of the respective components of the ceramics. When the mole percentage of each component is known, the required mass of the raw material can be calculated according to parameters such as the molecular weight of each component, the purity of the raw material and the like. The mass required by each component is calculated according to the required mole number and molecular weight of each component, and the required mass of the raw material is calculated according to the required mass of each component and the purity of the raw material. This makes it possible to prepare raw materials of corresponding weights based on the results of the calculation.

In some embodiments, modifying additives may also be added to the raw materials. The modifying additive may be Ta₂O₅、Bi₂O₃Or SiO₂One or more of the above. The proportion of the modifying additive in the total mole number of all raw materials can be 0.01-0.1%.

S1102: adding an organic solvent and grinding balls and carrying out primary ball milling.

In step S1102, deionized water, alcohol, acetone, etc. may be used as the organic solvent, zirconium balls, agate balls, etc. may be used as the grinding balls, and ceramic, polyurethane, nylon, etc. may be used in the grinding tank, and the ball milling is performed in planetary mill, stirring mill, tumbling mill, vibrating mill, etc. Wherein, in order to improve the ball milling effect, proper dispersant can be added or the pH value of the slurry can be adjusted.

In some embodiments, deionized water may be used as the organic solvent, and zirconia or agate grinding balls may be used, and the weighed raw materials may be charged into a polyurethane ball mill tank and mixed by adding the organic solvent and grinding balls. In step S1102, accurately weighed raw materials are poured into a ball mill pot, and deionized water and ZrO are added₂The grinding ball is prepared by mixing raw material, grinding ball and deionized water at a weight ratio of 1: 2-4: 1-2 (for example, 1: 2-4: (1))3:1.5 or 1:2:1.5) and ball-milling for 20 to 30 hours (e.g., 24 to 26 hours).

S1103: and drying the slurry obtained by the primary ball milling, and calcining to obtain the ceramic body.

And (3) uniformly mixing the ball-milled materials, discharging and drying, for example, drying the materials at 100-120 ℃.

After the ball milling is finished and the mixture obtained after drying is required to be calcined at a certain temperature to synthesize the ceramic body, wherein the calcining temperature and the heat preservation time depend on the corresponding formula. For example, in this embodiment, the slurry dried after ball milling can be placed in an alumina crucible and calcined at 1100-1300 ℃ for 1-5 hours (e.g., 2-4 hours) to synthesize a ceramic body.

S1104: and (3) crushing the ceramic body, adding an organic solvent and grinding balls, and carrying out secondary ball milling.

The synthesized ceramic body is pulverized. The method of pulverization is not limited in the present application, and for example, it may be pulverized using a pulverizer. In some embodiments, the crushed ceramic body may also be sieved (e.g., 40 mesh).

And pouring the crushed ceramic body into the ball milling tank again for secondary ball milling, wherein the process of the secondary ball milling can be similar to that of the primary ball milling. For example, the ratio of the material, the grinding balls and the deionized water can be kept unchanged, and the crushed ceramic body is subjected to secondary ball milling for 20-30 hours (for example, 24-26 hours). It should be understood that the process of the second ball milling may be different from the first ball milling, for example, the time of the second ball milling may be less than (or greater than) the time of the first ball milling, or the ratio of the materials, milling balls and deionized water in the second ball milling may be different from the first ball milling, for example, may be 1:2: 1.5.

S1105: and drying the slurry obtained by secondary ball milling.

Similarly, the ball-milled materials can be uniformly mixed, discharged and dried. In some embodiments, the dried slurry may also be screened (e.g., through a 40 mesh screen).

S1106: mixing the obtained powder with a binder to form slurry, and granulating.

In some embodiments, the binder may be a polyvinyl alcohol solution with a concentration of 5 wt% to 11 wt% (e.g., 5 wt% to 8 wt%) (i.e., the polyvinyl alcohol in the binder is 5 wt% to 11 wt%). The binder may account for 10% to 15% of the total mass of the mixed slurry.

In some embodiments, the granulated powder may also be sieved (e.g., 40 mesh).

S1107: and dry-pressing and molding in a mold matched with the shape of the first dielectric block, the second dielectric block or the dielectric coupling plate.

Specifically, the granulated powder is placed in a mold matched with the shape of the first medium block, the second medium block or the medium coupling plate, and is dry-pressed under a proper pressure, for example, the powder can be dry-pressed under a pressure of 100 to 150 MPa.

In other embodiments, the shape of the mold can be selected as desired, for example, if testing is desired, a test-specific mold can be used to dry-press the powder into aphi 12 × 6mm disk for ease of testing.

S1108: and removing the binder and sintering again to obtain the first dielectric block, the second dielectric block or the dielectric coupling plate.

The temperature may be selected to be a proper temperature for performing a heat preservation process, so as to remove the binder introduced in step S1106, and then sintering is performed again, so as to finally obtain the desired first dielectric block, second dielectric block or dielectric coupling plate. Specifically, in this embodiment, the molded material can be heat-preserved at 550-650 ℃ for 1-3 hours, and then sintered at 1400-1600 ℃ (e.g., 1450-1550 ℃) for 1-5 hours (e.g., 2-4 hours). In this way, the adhesive added to the material in step S1106 can be removed, and the first dielectric block, the second dielectric block or the dielectric coupling plate with the desired shape can be obtained.

The present application further provides a method for manufacturing a dielectric filter according to a first embodiment, in which the dielectric filter disclosed in the above embodiment is manufactured by the method for manufacturing a dielectric filter, as shown in fig. 12, the method includes the steps of:

s1201: providing a first dielectric block, a second dielectric block and a dielectric coupling plate.

The first dielectric block, the second dielectric block and the dielectric coupling plate are all prepared by the method for preparing the dielectric block, namely the dielectric block prepared by the steps S1101-S1108. The shapes of the first dielectric block, the second dielectric block and the dielectric coupling plate are the same as the preset shape of the dielectric filter.

S1202: and covering metal layers on the surfaces of the first dielectric block, the second dielectric block and the dielectric coupling plate to obtain the dielectric filter.

The first dielectric block, the second dielectric block and the dielectric coupling plate can be fixed by welding or formed by one-time sintering, and then metal layers are covered on the surfaces of the first dielectric block, the second dielectric block and the dielectric coupling plate, so that an electromagnetic field is limited in the dielectric blocks, and electromagnetic signal leakage is prevented. The metal layer may be made of silver, copper, aluminum, titanium, tin or gold, and the metal layer may be coated on the surface of the dielectric block by electroplating, spraying or welding.

As shown in fig. 13, thecommunication device 1301 of this embodiment includes adielectric filter 1303 and anantenna 1302, where thedielectric filter 1303 is coupled to theantenna 1302, and thedielectric filter 1303 is used for filtering a transmission/reception signal of theantenna 1302. Thedielectric filter 1303 in this embodiment is the dielectric filter in the above embodiment, and the structure and the working principle thereof are not described herein again.

Thecommunication device 1301 may be a base station or a terminal for 5G communication, and the terminal may specifically be a mobile phone, a tablet computer, a wearable device with a 5G communication function, and the like.

It should be noted that the above embodiments belong to the same inventive concept, and the description of each embodiment has a different emphasis, and reference may be made to the description in other embodiments where the description in individual embodiments is not detailed.

The protection circuit and the control system provided by the embodiment of the present application are described in detail above, and a specific example is applied in the description to explain the principle and the embodiment of the present application, and the description of the above embodiment is only used to help understand the method and the core idea of the present application; meanwhile, for a person skilled in the art, according to the idea of the present application, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present application.

The above description is only for the purpose of illustrating embodiments of the present application and is not intended to limit the scope of the present application, and all modifications of equivalent structures and equivalent processes, which are made by the contents of the specification and the drawings of the present application or are directly or indirectly applied to other related technical fields, are also included in the scope of the present application.

Claims (10)

1. A dielectric filter, characterized in that the dielectric filter comprises:

a first dielectric resonator including at least a first dielectric block;

a second dielectric resonator including at least a second dielectric block;

the dielectric coupling plate is arranged between the first dielectric block and the second dielectric block and connected with the first dielectric block and the second dielectric block, and the dielectric coupling plate is used for realizing the coupling between the first dielectric resonator and the second dielectric resonator; wherein, the material of the dielectric filter at least comprises strontium carbonate, samarium oxide, aluminum oxide and titanium dioxide.

2. The dielectric filter of claim 1, wherein the strontium carbonate accounts for 48-62% by mole; the samarium sesquioxide accounts for 10 to 24 percent of the molar percentage; the molar percentage of the aluminum oxide is 10 to 24 percent; the titanium dioxide accounts for 4 to 18 percent by mole.

3. The dielectric filter of claim 1, wherein the first dielectric resonator further comprises a first metal layer overlying a surface of the first dielectric block, and the second dielectric resonator further comprises a second metal layer overlying a surface of the second dielectric block;

the first metal layer is provided with a first opening, the second metal layer is provided with a second opening, the first opening and the second opening form the window, and the medium coupling plate is arranged in the window.

4. The dielectric filter according to claim 1, wherein the dielectric coupling plate, the first dielectric block, and the second dielectric block are formed by one-time sintering;

the dielectric filter further comprises a metal layer covering the surfaces of the first dielectric block, the second dielectric block and the dielectric coupling plate.

5. A dielectric filter according to claim 1, wherein the dielectric coupling plate has an extension in a plane parallel to the gap between the first dielectric block and the second dielectric block that is longer than a half wavelength of an operating frequency of the dielectric filter for reversing the polarity of coupling between the first dielectric resonator and the second dielectric resonator;

the dielectric coupling plate includes at least: the medium comprises a first medium part and a second medium part extending from the end part or the middle part of the first medium part, wherein the first medium part and the second medium part form an angle with each other in a range of 0-90 degrees;

the cross section of the dielectric coupling plate parallel to the gap between the first dielectric block and the second dielectric block is in an arch shape or a C shape;

the medium coupling plate is located in the middle of a gap between the first medium block and the second medium block.

6. The dielectric filter according to claim 1, further comprising a first adjusting member provided on a surface of the first dielectric resonator for adjusting the resonance frequency of the first dielectric resonator, and a second adjusting member provided on a surface of the second dielectric resonator for adjusting the resonance frequency of the second dielectric resonator;

the dielectric filter further comprises a third adjusting piece arranged on the surface of the dielectric coupling plate and used for adjusting the coupling strength between the first dielectric resonator and the second dielectric resonator.

7. The dielectric filter of claim 1, wherein the dielectric filter has a chemical composition aSrCO₃-bSm₂O₃-cAl₂O₃-dTiO₂Wherein the ratio of a, b, c and d is 0.48-0.62: 0.1-0.24: 0.04-0.18.

8. A method of preparing a dielectric block for use in preparing a first dielectric block, a second dielectric block or a dielectric coupling plate as claimed in any one of claims 1 to 7, the method comprising:

providing raw materials of strontium carbonate, samarium oxide, aluminum oxide and titanium dioxide;

adding an organic solvent and grinding balls and carrying out primary ball milling;

drying the slurry obtained by the primary ball milling, and calcining to obtain a ceramic body;

crushing the ceramic body, adding an organic solvent and grinding balls, and performing secondary ball milling;

drying the slurry obtained by the secondary ball milling;

mixing the obtained powder with a binder to form slurry, and granulating;

dry-pressing and molding in a mold matched with the shape of the first dielectric block, the second dielectric block or the dielectric coupling plate; and

and removing the binder and sintering again to obtain the first dielectric block, the second dielectric block or the dielectric coupling plate.

9. A method for producing a dielectric filter, the method being used for producing a dielectric filter according to any one of claims 1 to 7, the method comprising:

providing a first dielectric block, a second dielectric block and a dielectric coupling plate, wherein the first dielectric block, the second dielectric block and the dielectric coupling plate are all prepared by the method of claim 8;

and covering metal layers on the surfaces of the first dielectric block, the second dielectric block and the dielectric coupling plate to obtain the dielectric filter.

10. A communication device, comprising the dielectric filter according to any one of claims 1 to 7 and an antenna, wherein the dielectric filter is coupled to the antenna, and wherein the dielectric filter is configured to filter a transceived signal of the antenna.

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