CN212323179U - Filter and communication equipment - Google Patents

Abstract

The application discloses a filter and communication equipment. The filter includes: a housing; the filtering branch is arranged on the shell and consists of eleven filtering cavities which are sequentially coupled; capacitive cross coupling is respectively carried out between a second filtering cavity and a fourth filtering cavity, between the fourth filtering cavity and a sixth filtering cavity, between the sixth filtering cavity and a ninth filtering cavity and between a seventh filtering cavity and the ninth filtering cavity of the filtering branch circuit; the ninth filtering cavity and the eleventh filtering cavity of the filtering branch circuit are inductively and cross-coupled; the bandwidth range of the filtered branch is 2515MHz-2675 MHz. In this way, the stop-band rejection performance of the filter can be improved.

Description

Filter and communication equipment

Technical Field

The present application relates to the field of communications technologies, and in particular, to a filter and a communications device.

Background

The cavity filter is a key device of a modern mobile communication system and is widely applied to wireless communication base stations and various communication terminals; the cavity filter is composed of a radio frequency connector, a cavity, a cover plate, a plurality of resonator units and a frequency tuning and coupling strength adjusting component, wherein the resonant frequencies of the plurality of resonator units are distributed in the passband range, and the cavity filter has a blocking function for signals outside the resonant frequencies, so that the function of selecting microwave transmission signals is realized; the cavity filter has the advantages of reliable structure, wide filtering frequency band, parasitic pass band far away from a channel, high Q value, stable electrical property, good heat dissipation performance and the like.

The inventor of the application finds that the arrangement of a plurality of filter cavities in the existing cavity filter is complex and irregular, the size of the filter is increased, and the stop band inhibition performance of the cavity filter is poor.

SUMMERY OF THE UTILITY MODEL

The technical problem that this application mainly solved provides a wave filter and communication equipment to improve the stop band rejection performance of wave filter.

In order to solve the technical problem, the application adopts a technical scheme that: there is provided a filter comprising: a housing; the filtering branch is arranged on the shell and consists of eleven filtering cavities which are sequentially coupled; capacitive cross coupling is respectively carried out between a second filtering cavity and a fourth filtering cavity, between the fourth filtering cavity and a sixth filtering cavity, between the sixth filtering cavity and a ninth filtering cavity and between a seventh filtering cavity and the ninth filtering cavity of the filtering branch circuit; the ninth filtering cavity and the eleventh filtering cavity of the filtering branch circuit are inductively and cross-coupled; the bandwidth range of the filtered branch is 2515MHz-2675 MHz.

Optionally, eleven filter cavities of the filter branch are divided into five rows arranged along a first direction, and the first direction and the second direction are perpendicular to each other; the first filtering cavities and the second filtering cavities of the filtering branch circuits are arranged in a row along a second direction; the fifth filtering cavity, the fourth filtering cavity and the third filtering cavity of the filtering branch circuit are arranged in a row along the second direction; the sixth filtering cavity and the seventh filtering cavity of the filtering branch are arranged in a row along the second direction; the ninth filtering cavity and the eighth filtering cavity of the filtering branch circuit are arranged in a row along the second direction; the tenth filtering cavity and the eleventh filtering cavity of the filtering branch are arranged in a row along the second direction. Eleven filter cavities are divided into five rows which are sequentially arranged along the first direction, and the eleven filter cavities are regularly arranged, so that the size of the filter branch is reduced, and further, the size of the filter is reduced.

Optionally, the eleventh filtering cavity, the ninth filtering cavity, the sixth filtering cavity and the fifth filtering cavity of the filtering branch are in a row and are arranged in sequence in a straight line; the eighth filtering cavity, the seventh filtering cavity, the fourth filtering cavity and the first filtering cavity of the filtering branch are in a row and are sequentially arranged in a straight line; the third filtering cavities and the second filtering cavities of the filtering branch are in a row and are sequentially arranged in a straight line; the projections of the tenth filtering cavity of the filtering branch between the eleventh filtering cavity and the ninth filtering cavity which are a straight line are positioned between the connecting lines of the eleventh filtering cavity and the ninth filtering cavity. A plurality of filtering cavities of the filtering branch circuit are arranged in a straight line, so that the structure is simplified, and the design and the arrangement are facilitated.

Optionally, an included angle between a connecting line of the center of the third filter cavity and the center of the second filter cavity of the filter branch and a connecting line of the center of the third filter cavity and the center of the fourth filter cavity is an acute angle; an included angle between a connecting line of the centers of the sixth filtering cavity and the fifth filtering cavity of the filtering branch and a connecting line of the centers of the third filtering cavity and the fifth filtering cavity is an acute angle; and an included angle between a connecting line of the centers of the eleventh filtering cavity and the ninth filtering cavity of the filtering branch and a connecting line of the centers of the eighth filtering cavity and the ninth filtering cavity is an acute angle. The included angles of a plurality of filtering cavities of the filtering branch circuit are acute angles, so that the positions of the filtering cavities are further limited, the structure is further simplified, and design and arrangement are facilitated.

Optionally, flying rods are respectively arranged between a second filtering cavity and a fourth filtering cavity, between the fourth filtering cavity and a sixth filtering cavity, between the sixth filtering cavity and a ninth filtering cavity, and between a seventh filtering cavity and the ninth filtering cavity of the filtering branch; the flying rod comprises a first coupling part, a second coupling part and a connecting part, wherein two ends of the connecting part are respectively connected with the first coupling part and the second coupling part; the flying rod comprises a supporting clamping seat and a capacitive coupling probe, the flying rod is fixed on the supporting clamping seat, and supporting clamping seats are arranged on windows between a second filtering cavity and a fourth filtering cavity, between the fourth filtering cavity and a sixth filtering cavity, between the sixth filtering cavity and a ninth filtering cavity and between a seventh filtering cavity and the ninth filtering cavity of the filtering branch. Capacitive cross coupling between the second filter cavity and the fourth filter cavity, between the fourth filter cavity and the sixth filter cavity, between the sixth filter cavity and the ninth filter cavity, and between the seventh filter cavity and the ninth filter cavity of the filter branch can be realized through the flying rod.

Eleven filter cavities of the filter branch circuit are sequentially window-coupled; eleven filter cavities of the filter branch circuit are sequentially window-coupled; and a first metal coupling rib is arranged between the ninth filtering cavity and the eleventh filtering cavity of the filtering branch circuit to form an inductive cross coupling zero point. And the first metal coupling rib is arranged, so that the ninth filtering cavity and the eleventh filtering cavity are inductively and cross-coupled.

Second metal coupling ribs are arranged between the first filtering cavity and the second filtering cavity of the filtering branch circuit, between the second filtering cavity and the third filtering cavity, between the third filtering cavity and the fourth filtering cavity, between the fifth filtering cavity and the sixth filtering cavity, between the sixth filtering cavity and the seventh filtering cavity, between the seventh filtering cavity and the eighth filtering cavity, between the eighth filtering cavity and the ninth filtering cavity, and between the tenth filtering cavity and the eleventh filtering cavity, so that energy coupling is enhanced. Through setting up the second metal coupling muscle, improve on the coupling path between adjacent first filter chamber and the second filter chamber, between second filter chamber and the third filter chamber, between third filter chamber and the fourth filter chamber, between fifth filter chamber and the sixth filter chamber, between sixth filter chamber and the seventh filter chamber, between seventh filter chamber and the eighth filter chamber, between eighth filter chamber and the ninth filter chamber, the coupling intensity between tenth filter chamber and the eleventh filter chamber, thereby promote energy transmission's coupling quality.

Optionally, each filter cavity of the filter branch is provided with a resonance rod and a tuning rod; the resonance rod comprises a U-shaped side wall and a hollow inner cavity formed by the U-shaped side wall; one end of the tuning rod is arranged in the hollow inner cavity; the two ends of the U-shaped side wall bend and extend in the direction away from the hollow inner cavity so as to form disc-shaped structures at the two ends of the U-shaped side wall, and the disc-shaped structures are arranged in parallel with the bottom of the U-shaped side wall; each filtering cavity of the filtering branch is also provided with a mounting column, and the U-shaped side wall is fixed on the mounting column.

Therefore, the disc-shaped structures at the two ends of the U-shaped side wall can increase the signal coupling amount of the resonance rod. The resonant rod may be secured to the housing by a mounting post and the resonant frequency of the resonant cavity may be adjusted by adjusting the depth of the tuning rod within the hollow cavity.

The filter further comprises: the first port is connected with the first filtering cavity of the filtering branch circuit; and the second port is connected with the eleventh filtering cavity of the filtering branch circuit. The filtering branch circuit is convenient to design and manufacture by arranging the first port and the second port, and is favorable for improving the implementation of a scheme.

In order to solve the above technical problem, the present application adopts another technical solution: a communication device is provided. The communication equipment comprises an antenna and a radio frequency unit connected with the antenna, wherein the radio frequency unit comprises the filter and is used for filtering radio frequency signals.

The beneficial effect of this application is: different from the prior art, the filter of the embodiment of the application comprises: a housing; the filtering branch is arranged on the shell and consists of eleven filtering cavities which are sequentially coupled; capacitive cross coupling is respectively carried out between a second filtering cavity and a fourth filtering cavity, between the fourth filtering cavity and a sixth filtering cavity, between the sixth filtering cavity and a ninth filtering cavity and between a seventh filtering cavity and the ninth filtering cavity of the filtering branch circuit; the ninth filtering cavity and the eleventh filtering cavity of the filtering branch circuit are inductively and cross-coupled; the bandwidth range of the filtered branch is 2515MHz-2675 MHz. Inductive cross coupling is performed between a ninth filtering cavity and an eleventh filtering cavity of a filtering branch circuit in the embodiment of the application, high-end suppression of the bandwidth of the filtering branch circuit can be well controlled, and good high-end suppression of the bandwidth is obtained, capacitive cross coupling is respectively performed between the second filtering cavity and the fourth filtering cavity, between the fourth filtering cavity and the sixth filtering cavity, between the sixth filtering cavity and the ninth filtering cavity, and between the seventh filtering cavity and the ninth filtering cavity, four capacitive coupling zeros can be realized, low-end suppression of the bandwidth of the filter can be well controlled, and good low-end suppression of the bandwidth is obtained, so that the stop band suppression performance of the filter can be improved; in addition, the bandwidth range of the filtering branch circuit is 2515MHz-2675MHz, and the bandwidth of the filtering branch circuit can be accurately controlled.

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 diagram of an embodiment of a filter according to the present application;

FIG. 2 is a schematic diagram of the topology of the filter of the embodiment of FIG. 1;

FIG. 3 is a schematic structural diagram of a combined structure of a support clamping seat and a capacitive coupling probe in the filter of the embodiment of FIG. 1;

FIG. 4 is a schematic diagram of a metal coupling probe of the filter cavity of the embodiment of FIG. 1;

FIG. 5 is a schematic structural diagram of a tuning rod, a resonant rod and a mounting post combined structure of the filter cavity of FIG. 1;

FIG. 6 is a schematic diagram of an equivalent circuit configuration of the filter of the embodiment of FIG. 1;

FIG. 7 is a diagram illustrating a simulated structure of the filter of the embodiment of FIG. 1;

fig. 8 is a schematic structural diagram of an embodiment of the communication device of the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

The terms "first" and "second" in this application are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. In the description of the present application, "plurality" means at least two, e.g., two, three, etc., unless explicitly specifically limited otherwise. Furthermore, the terms "include" and "have," as well as any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, article, or apparatus that comprises a list of steps or elements is not limited to only those steps or elements listed, but may alternatively include other steps or elements not listed, or inherent to such process, method, article, or apparatus.

First, a filter is provided, please refer to fig. 1 and fig. 2, in which fig. 1 is a schematic structural diagram of a first embodiment of the filter of the present application, and fig. 2 is a schematic topological structural diagram of the filter of fig. 1. The filter 10 of the present embodiment includes: a housing 11 and eleven filter chambers; the filtering branch 12 is arranged on the shell 11 and consists of eleven filtering cavities which are coupled in sequence.

Specifically, the eleven filter cavities of the filter branch 12 include: the filter comprises a first filter cavity A1, a second filter cavity A2, a third filter cavity A3, a fourth filter cavity A4, a fifth filter cavity A5, a sixth filter cavity A6, a seventh filter cavity A7, an eighth filter cavity A8, a ninth filter cavity A9, a tenth filter cavity A10 and an eleventh filter cavity A11. Capacitive cross coupling is respectively formed between the second filter cavity A2 and the fourth filter cavity A4, between the fourth filter cavity A4 and the sixth filter cavity A6, between the sixth filter cavity A6 and the ninth filter cavity A9, and between the seventh filter cavity A7 and the ninth filter cavity A9 of the filter branch 12; the ninth filter cavity a9 and the eleventh filter cavity a11 of the filter branch 12 are inductively cross-coupled; wherein the bandwidth range of the filter 10 is 2515MHz-2675 MHz.

It can be seen that, the inductive cross coupling between the ninth filter cavity a9 and the eleventh filter cavity a11 of the filter branch 12 can well control the high-end rejection of the filter branch bandwidth, and obtain better high-end rejection of the bandwidth, and the capacitive cross coupling between the second filter cavity a2 and the fourth filter cavity a4, between the fourth filter cavity a4 and the sixth filter cavity a6, between the sixth filter cavity a6 and the ninth filter cavity a9, and between the seventh filter cavity a7 and the ninth filter cavity a9 respectively can realize four capacitive coupling zeros, can well control the low-end rejection of the filter bandwidth, and obtain better low-end rejection, so that the stop band rejection performance of the filter 10 can be improved; in addition, the bandwidth of the filtering branch circuit 12 ranges from 2515MHz to 2675MHz, and the bandwidth of the filtering branch circuit 12 can be accurately controlled.

The filter 10 is a communication device for frequency selection and signal suppression, and its filter cavity mainly plays a role of frequency control, and the filter cavity is required for the communication device related to frequency transmission and reception.

As shown in fig. 1, the eleven filter cavities of the filter branch 12 are divided into five rows arranged along a first direction x, and the first direction x and the second direction y are arranged perpendicular to each other; the first filter cavity a1 and the second filter cavity a2 of the filter branch 12 are arranged in a line along the second direction y; the fifth filter cavity a5, the fourth filter cavity a4 and the third filter cavity A3 of the filter branch 12 are arranged in a row along the second direction y; the sixth filter cavity a6 and the seventh filter cavity a7 of the filter branch 12 are arranged in a line along the second direction y; the ninth filter cavity a9 and the eighth filter cavity A8 of the filter branch 12 are arranged in a row along the second direction y; the tenth filter chamber a10 and the eleventh filter chamber a11 of the filter branch 12 are arranged in a row along the second direction y.

It can be seen that the eleven filter cavities are divided into five rows arranged in sequence along the first direction x, and the eleven filter cavities are regularly arranged, so as to reduce the volume of the filter branch 12 and thus the filter 10.

The eleventh filtering cavity a11, the ninth filtering cavity a9, the sixth filtering cavity a6 and the fifth filtering cavity a5 of the filtering branch 12 are in a row and are sequentially arranged in a straight line; the eighth filtering cavity A8, the seventh filtering cavity a7, the fourth filtering cavity a4 and the first filtering cavity a1 of the filtering branch 12 are in a row and are sequentially arranged in a straight line; the third filtering cavity A3 and the second filtering cavity a2 of the filtering branch 12 are in a row and are sequentially arranged in a straight line; the projection of the tenth filter cavity a10 of the filter branch 12 on the straight line between the eleventh filter cavity a11 and the ninth filter cavity a9 is between the connecting lines of the eleventh filter cavity a11 and the ninth filter cavity a 9. The plurality of filter cavities of the filter branch 12 are arranged in a straight line, so that the structure is simplified, and the design and the arrangement are facilitated.

Furthermore, an included angle between a connecting line of the center of the third filter cavity A3 and the center of the second filter cavity a2 of the filter branch 12 and a connecting line of the center of the third filter cavity A3 and the center of the fourth filter cavity a4 is an acute angle, and the acute angle may be 20 °, 30 °, 50 °, 60 °, and the like, and is not limited herein; an included angle between a connecting line of the center of the sixth filter cavity a6 and the center of the fifth filter cavity a5 of the filter branch 12 and a connecting line of the center of the third filter cavity A3 and the center of the fifth filter cavity a5 is an acute angle, and the acute angle may be 20 °, 30 °, 50 °, 60 °, and the like, and is not limited herein; an included angle between a connecting line of the center of the eleventh filter cavity a11 and the center of the ninth filter cavity a9 of the filter branch 12 and a connecting line of the center of the eighth filter cavity A8 and the center of the ninth filter cavity a9 is an acute angle, and the acute angle may be 20 °, 30 °, 50 °, 60 °, and the like, and is not limited herein. The included angles of the plurality of filtering cavities of the filtering branch circuit 12 are acute angles, so that the positions of the filtering cavities are further limited, the structure is further simplified, and design and arrangement are facilitated.

Optionally, flying rods are respectively arranged between the second filter cavity a2 and the fourth filter cavity a4, between the second filter cavity a2 and the fifth filter cavity a5, and between the fifth filter cavity a5 and the seventh filter cavity a7 of the filter branch 12. Capacitive cross-coupling between the second filter chamber a2 and the fourth filter chamber a4, between the second filter chamber a2 and the fifth filter chamber a5, and between the fifth filter chamber a5 and the seventh filter chamber a7 may be achieved by flying rods.

As shown in FIG. 2, the ninth filtering cavity A9 and the eleventh filtering cavity A11 of the filtering branch 12 are inductively cross-coupled to form an inductive coupling zero L₁(ii) a The second filter cavity A2 and the fourth filter cavity A4 are capacitively cross-coupled to form a capacitive coupling zero point C₁The fourth filter cavity A4 and the sixth filter cavity A6 are capacitively cross-coupled to form a capacitive coupling zero point C₂The sixth filter cavity A6 and the ninth filter cavity A9 are capacitively cross-coupled to form a capacitively coupled zero C₃The seventh filter cavity A7 and the ninth filter cavity A9 are capacitively cross-coupled to form a capacitively coupled zero C₄To form five cross-coupling zeros of the filter branch 12. The cross-coupling zero is also referred to as a transmission zero. The transmission zero is the transmission function of the filter 10 equal to zero, that is, the electromagnetic energy at the frequency point corresponding to the transmission zero cannot pass through the network, so that the complete isolation effect is achieved, the suppression effect on the signals outside the passband is achieved, and the high isolation among a plurality of passbands can be better achieved.

Referring to fig. 3, fig. 3 is a schematic structural diagram of a combination structure of a support card seat and a capacitive coupling probe in the filter of the embodiment of fig. 1. Optionally, the flying bar comprises a supporting clamping seat 70 and a capacitive coupling probe 60, the capacitive coupling probe 60 is fixed on the supporting clamping seat 70, and the supporting clamping seat 70 is arranged on the windows between the second filter cavity a2 and the fourth filter cavity a4, between the fourth filter cavity a4 and the sixth filter cavity a6, between the sixth filter cavity a6 and the ninth filter cavity a9, and between the seventh filter cavity a7 and the ninth filter cavity a9 of the filter branch 12.

Specifically, the capacitive coupling probe 60 includes a first coupling portion 610, a second coupling portion 620 and a connecting portion 630, two ends of the connecting portion 630 are respectively connected to the first coupling portion 610 and the second coupling portion 620, and the first coupling portion 610 and the second coupling portion 620 are located on the same side of the connecting portion 630. The first coupling part 610, the connecting part 630 and the second coupling part 620 are sequentially connected to form a flying bar; the first coupling part 610 is coupled to the resonance rod 20 in the second filter cavity a2 such that a coupling capacitance is formed between the first coupling part 610 and the resonance rod 20, and the second coupling part 620 is coupled to the resonance rod 20 in the fourth filter cavity a4 such that a coupling capacitance is formed between the second coupling part 620 and the resonance rod 20.

Similarly, a flying rod is also arranged between the fourth filtering cavity a4 and the sixth filtering cavity a6, between the sixth filtering cavity a6 and the ninth filtering cavity a9, and between the seventh filtering cavity a7 and the ninth filtering cavity a9, and the structure and the specific connection mode of the flying rod are similar to those of the flying rod arranged between the second filtering cavity a2 and the fourth filtering cavity a4, which is not described herein again.

As shown in fig. 1 and 3, a support socket 70 may be disposed on the housing 11, and the support socket 70 is provided with a through hole (not shown), wherein the connecting portion 630 penetrates through the through hole to fix the capacitive coupling probe 60 on the support socket 70.

The capacitive coupling probe 60 of the present embodiment can be implemented by a metal probe, the supporting card seat 70 is implemented by PTFE or engineering plastics, and specifically, referring to fig. 4, fig. 4 is a schematic structural diagram of the metal coupling probe of the filter cavity of the embodiment of fig. 1, the metal coupling probe 61 is in a dumbbell shape and includes a first coupling portion 611, a second coupling portion 621 and a connecting portion 631, two ends of the connecting portion 631 are respectively connected to the first coupling portion 611 and the second coupling portion 621, and the first coupling portion 611 and the second coupling portion 621 are located on the same side of the connecting portion 631. The first coupling part 611, the connection part 631, and the second coupling part 621 are sequentially connected to form a metal coupling probe 61.

As shown in fig. 1, eleven filter cavities of the filter branch 12 are sequentially window-coupled, and a second window is disposed between two filter cavities of the filter branch 12. Namely, the window coupling between the first filter cavity a1 and the second filter cavity a2, the window coupling between the second filter cavity a2 and the third filter cavity A3, the window coupling between the third filter cavity A3 and the fourth filter cavity a4, the window coupling between the fourth filter cavity a4 and the fifth filter cavity A5, the window coupling between the fifth filter cavity A5 and the sixth filter cavity A6, the window coupling between the sixth filter cavity A6 and the seventh filter cavity a7, the window coupling between the seventh filter cavity a7 and the eighth filter cavity A8, the window coupling between the eighth filter cavity A8 and the ninth filter cavity a9, the window coupling between the ninth filter cavity a9 and the tenth filter cavity a10, and the window coupling between the tenth filter cavity a10 and the eleventh filter cavity a 11.

Therefore, the two adjacent filter cavities on the coupling path of the filter branch 12 are coupled by pure windows, so that the cost of the filter 10 is reduced.

In addition, a first window is disposed between the ninth filter cavity a9 and the eleventh filter cavity a11 of the filter branch 12, and specifically, in order to adjust the coupling strength of the inductive cross coupling between the seventh filter cavity a7 and the ninth filter cavity a9, a first metal coupling rib 80 may be disposed between the first windows, and through the first metal coupling rib 80, the inductive cross coupling between the seventh filter cavity a7 and the ninth filter cavity a9 may be achieved, so as to form an inductive cross coupling zero point.

Second metal coupling ribs 81 are arranged between the first filtering cavity a1 and the second filtering cavity a2, between the second filtering cavity a2 and the third filtering cavity A3, between the third filtering cavity A3 and the fourth filtering cavity a4, between the fifth filtering cavity a5 and the sixth filtering cavity A6, between the sixth filtering cavity A6 and the seventh filtering cavity a7, between the seventh filtering cavity a7 and the eighth filtering cavity A8, between the eighth filtering cavity A8 and the ninth filtering cavity a9, and between the tenth filtering cavity a10 and the eleventh filtering cavity a11 of the filtering branch 12, so as to enhance energy coupling. By arranging the second metal coupling rib 81, the coupling strength between the first filter cavity a1 and the second filter cavity a2, between the second filter cavity a2 and the third filter cavity A3, between the third filter cavity A3 and the fourth filter cavity a4, between the fifth filter cavity a5 and the sixth filter cavity A6, between the sixth filter cavity A6 and the seventh filter cavity a7, between the seventh filter cavity a7 and the eighth filter cavity A8, between the eighth filter cavity A8 and the ninth filter cavity a9, and between the tenth filter cavity a10 and the eleventh filter cavity a11 which are adjacent on the coupling path is improved, so that the coupling quality of energy transmission is improved.

Referring to fig. 5, fig. 5 is a schematic structural diagram of a tuning rod, a resonant rod and a mounting post combined structure of the filter cavity of fig. 1. Optionally, each filter cavity is provided with: a resonant rod 20 including a U-shaped sidewall 210 and a hollow interior 220 formed by the U-shaped sidewall 210; a tuning rod 30, one end of the tuning rod 30 being disposed within the hollow interior 220; the two ends of the U-shaped sidewall 210 are bent and extended away from the hollow cavity 220, so as to form a disc-shaped structure 230 at the two ends of the U-shaped sidewall 210 and parallel to the bottom of the U-shaped sidewall 210. The housing 11 is further provided with a mounting post 40, the U-shaped sidewall 210 is fixed on the mounting post 40, and the resonant rod 20 is fixed on the housing 11 through the mounting post 40.

Therefore, the disc-shaped structures at both ends of the U-shaped sidewall 210 can increase the signal coupling amount of the resonant rod 20. The resonant rod 20 is secured to the housing 11 by the mounting post 40 and the resonant frequency of the resonant cavity is adjusted by adjusting the depth of the tuning rod 30 within the hollow interior 220.

The resonant rod 20, the hollow cavity 220 and the tuning rod 30 of the present embodiment are coaxially disposed.

Further, a mounting hole (not shown) may be formed in the bottom of the U-shaped sidewall 210, one end of the mounting post 40 is fixed to the housing 11, and the other end of the mounting post 40 is mounted in the mounting hole, so as to fix the resonant rod 20 to the mounting post 40; the mounting holes may be through holes, the mounting holes may be threaded holes, and the mounting posts 40 are studs. In other embodiments, the mounting hole may also be a blind hole.

The material of the resonant rod 20 of the present embodiment may be the cut 1215 MS. Of course, in other embodiments, the resonant rod 20 may be an M8 or M4 screw rod, and may be made of copper or silver.

Eleven filter chambers have the same size, so that the production is convenient and the cost is saved. The eleven filter cavities may have a radius of less than 21mm, e.g., 20mm, 19mm, 18mm, etc. Eleven filter cavities can be realized by combining a metal cavity, a metal resonance rod and a tuning screw rod, the size of the resonance cavity is 28mm x 26mm, and in order to realize the low temperature drift characteristic, the resonance rod 20 is made of invar steel; to achieve high power carrying requirements, the resonant rod 20 can be made to have a frequency of 2.6GHz by using a turning plate.

It can be seen that the resonant rod 20 can be secured to the housing 11 by the mounting post 40 and the resonant frequency of the resonant cavity can be adjusted by adjusting the depth of the tuning rod 30 within the hollow interior 220.

Further, the filter 10 further includes a cover plate (not shown) covering the eleven filter cavities, and the other end of the tuning rod 30 penetrates the cover plate, wherein the tuning rod 30 may be a metal screw rod.

The filter 10 further comprises: a first port connected to the first filter cavity a1 of the filter branch 12; and a second port connected to the eleventh filter cavity a11 of the filter branch 12. The filtering branch 12 is convenient to design and manufacture by arranging the first port and the second port, and is beneficial to the realization of a lifting scheme.

The equivalent circuit of the filter 10 of this embodiment is shown in fig. 6, where the impedance Z1 at the input port is about 50 ohms, and the impedance Z2 at the output port is about 50 ohms; in order to ensure that electromagnetic signals are transmitted between the eleven filter cavities of the filter 10, impedance adjusters ZV1 are respectively disposed between the input port and the first filter cavity a1, between adjacent filter cavities on the coupling path, between non-cascaded filter cavities forming cross coupling, and between the eleventh filter cavity a11 and the output port, so as to achieve impedance matching.

The simulation result of the filter 10 of the present embodiment is shown in fig. 7, and it can be known from fig. 7 that the bandwidth of the filter 10 of the present embodiment is about 2515MHz-2675 MHz; there are three low-side coupling zeros a, b, c and two high-side coupling zeros d, e, as shown in the frequency band curve S1. The suppression of the frequency point 2.505GHz (m3) is-31.601 dB, the suppression of the frequency point 2.500GHz (m4) is-68.109 dB, the suppression of the frequency point 2.4835GHz (m5) is-79.7679 dB, the suppression of the frequency point 2.395GHz (m6) is-89.608 dB, the suppression of the frequency point 2.685GHz (m7) is-23.334 dB, the suppression of the frequency point 2.695GHz (m8) is-60.203 dB, the suppression of the frequency point 2.700GHz (m9) is-62.820 dB, the suppression of the frequency point 2.795GHz (m10) is-80.200 dB, the suppression of the frequency point 2.515GHz (m11) is-1.304 dB, and the suppression of the frequency point 2.675GHz (m12) is-1.186 dB, so that the design requirement of out-band suppression of the filter 10 can be met.

The filter 10 of the embodiment is a 9-order microwave filter applied to a 5G mobile communication system, the working frequency band of the filter is 2515MHz-2675MHz, the in-band fluctuation is less than 1dB, the average insertion loss is low, and particularly the average insertion loss of any 5MHz is less than 1.2 dB; the high remote inhibition has the inhibition requirement in the frequency band of 18 GHz; the power capacity is large, and the bearing power at normal temperature and normal pressure is more than 700W.

Therefore, the filter 10 in the embodiment of the application has low loss, and can ensure low energy consumption of the communication module; the filter 10 is designed by combining 11-order resonant cavities, and a coupling zero structure is introduced, so that the filter has strong anti-interference capability and can ensure that a communication system is not interfered by stray signals; the filter 10 has a simple design scheme, low cost, and good structural and electrical performance stability; the filter 10 can meet the use of the current latest 5G mobile communication system, and the filter 10 mainly relates to the 2.6GHz band.

The present application further provides a communication device, as shown in fig. 8, fig. 8 is a schematic structural diagram of an embodiment of the communication device of the present application. The communication device of the present embodiment includes an antenna 92 and a radio frequency unit 91 connected to the antenna 92, the radio frequency unit 91 includes a filter 10 as shown in the above-mentioned embodiment, and the filter 10 is used for filtering a radio frequency signal.

In other embodiments, the rf Unit 91 may be integrated with the Antenna 92 to form an Active Antenna Unit (AAU).

Some embodiments of the present application are referred to as filters and may also be referred to as combiners, i.e., dual-frequency combiners. It is understood that in other embodiments, the duplexer may be referred to as a duplexer.

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 filter, characterized in that the filter comprises:

a housing;

the filtering branch is arranged on the shell and consists of eleven filtering cavities which are sequentially coupled; capacitive cross coupling is respectively carried out between a second filtering cavity and a fourth filtering cavity, between the fourth filtering cavity and a sixth filtering cavity, between the sixth filtering cavity and a ninth filtering cavity and between a seventh filtering cavity and the ninth filtering cavity of the filtering branch circuit; the ninth filtering cavity and the eleventh filtering cavity of the filtering branch circuit are inductively and cross-coupled; the bandwidth range of the filtered branch is 2515MHz-2675 MHz.

2. The filter of claim 1,

the eleven filter cavities are divided into five rows arranged along a first direction, and the first direction and the second direction are perpendicular to each other;

the first filtering cavities and the second filtering cavities of the filtering branch circuits are arranged in a row along the second direction;

the fifth filtering cavity, the fourth filtering cavity and the third filtering cavity of the filtering branch circuit are arranged in a row along the second direction;

the sixth filtering cavities and the seventh filtering cavities of the filtering branch are arranged in a row along the second direction;

the ninth filtering cavities and the eighth filtering cavities of the filtering branch are arranged in a row along the second direction;

and the tenth filtering cavity and the eleventh filtering cavity of the filtering branch are arranged in a row along the second direction.

3. The filter of claim 2,

the eleventh filtering cavity, the ninth filtering cavity, the sixth filtering cavity and the fifth filtering cavity of the filtering branch are sequentially arranged in a straight line;

the eighth filtering cavity, the seventh filtering cavity, the fourth filtering cavity and the first filtering cavity of the filtering branch circuit are sequentially arranged in a straight line;

and the third filtering cavity and the second filtering cavity of the filtering branch are arranged in sequence in a straight line.

4. The filter according to claim 2 or 3, wherein an included angle between a connecting line of a center of a third filter cavity of the filter branch and a center of the second filter cavity and a connecting line of the center of the third filter cavity and a center of the fourth filter cavity is an acute angle;

an included angle between a connecting line of the center of the sixth filtering cavity and the center of the fifth filtering cavity of the filtering branch and a connecting line of the center of the third filtering cavity and the center of the fifth filtering cavity is an acute angle;

and an included angle between a connecting line of the center of the eleventh filtering cavity and the center of the ninth filtering cavity of the filtering branch and a connecting line of the center of the eighth filtering cavity and the center of the ninth filtering cavity is an acute angle.

5. The filter of claim 3,

flying rods are respectively arranged between a second filtering cavity and a fourth filtering cavity, between the fourth filtering cavity and a sixth filtering cavity, between the sixth filtering cavity and a ninth filtering cavity and between a seventh filtering cavity and the ninth filtering cavity of the filtering branch circuit; the flying rod comprises a first coupling part, a second coupling part and a connecting part, wherein two ends of the connecting part are respectively connected with the first coupling part and the second coupling part;

the flying rod comprises a supporting clamping seat and a capacitive coupling probe, the flying rod is fixed on the supporting clamping seat, and the supporting clamping seat is arranged on windows between a second filtering cavity and a fourth filtering cavity of the filtering branch, between the fourth filtering cavity and a sixth filtering cavity, between the sixth filtering cavity and a ninth filtering cavity, and between a seventh filtering cavity and the ninth filtering cavity.

6. The filter of claim 1, wherein eleven filter cavities of the filter branch are sequentially window-coupled;

and a first metal coupling rib is arranged between the ninth filtering cavity and the eleventh filtering cavity of the filtering branch circuit to form an inductive cross coupling zero point.

7. The filter according to claim 6, wherein second metal coupling ribs are disposed between the first filter cavity and the second filter cavity, between the second filter cavity and the third filter cavity, between the third filter cavity and the fourth filter cavity, between the fifth filter cavity and the sixth filter cavity, between the sixth filter cavity and the seventh filter cavity, between the seventh filter cavity and the eighth filter cavity, between the eighth filter cavity and the ninth filter cavity, and between the tenth filter cavity and the eleventh filter cavity of the filter branch to enhance energy coupling.

8. The filter of claim 1,

each filtering cavity of the filtering branch circuit is provided with a resonance rod and a tuning rod;

the resonance rod comprises a U-shaped side wall and a hollow inner cavity formed by the U-shaped side wall;

one end of the tuning rod is arranged in the hollow inner cavity;

the two ends of the U-shaped side wall bend and extend in the direction away from the hollow inner cavity, so that disc-shaped structures are formed at the two ends of the U-shaped side wall, and the disc-shaped structures are arranged in parallel with the bottom of the U-shaped side wall;

each filtering cavity of the filtering branch is further provided with a mounting column, and the U-shaped side wall is fixed on the mounting column.

9. The filter of claim 1,

the first port is connected with the first filtering cavity of the filtering branch circuit;

and the second port is connected with the eleventh filtering cavity of the filtering branch circuit.

10. A communication device, characterized in that the communication device comprises an antenna and a radio frequency unit connected to the antenna, the radio frequency unit comprising a filter according to any of claims 1-9 for filtering a radio frequency signal.

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