CN113054345A

CN113054345A - Communication device and filter thereof

Info

Publication number: CN113054345A
Application number: CN201911380981.6A
Authority: CN
Inventors: 韩军平; 蔡永宏; 唐梦军; 马基良
Original assignee: Shenzhen Tatfook Technology Co Ltd
Current assignee: Shenzhen Tatfook Technology Co Ltd
Priority date: 2019-12-27
Filing date: 2019-12-27
Publication date: 2021-06-29

Abstract

The application discloses a communication device and a filter thereof, wherein the filter comprises a shell, a first side and a second side, wherein the first side and the second side are perpendicular to each other; the first common cavity and the second common cavity are arranged on one side of the shell at intervals; the first emission filtering branch circuit is respectively coupled with the first common cavity and the second common cavity and consists of five first emission filtering cavities which are sequentially coupled, and the five first emission filtering cavities further form an inductive cross coupling zero point; and the second emission filtering branch is respectively coupled with the first common cavity and the second common cavity and consists of five second emission filtering cavities which are sequentially coupled, and the five second emission filtering cavities further form a capacitive cross-coupling zero point. By the mode, the size of the filter can be reduced, and the out-of-band rejection performance of the filter can be improved.

Description

Communication device and filter thereof

Technical Field

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

Background

In a mobile communication system, a desired signal is modulated to form a modulated signal, the modulated signal is carried on a high-frequency carrier signal, the modulated signal is transmitted to the air through a transmitting antenna, the signal in the air is received through a receiving antenna, and the signal received by the receiving antenna does not include the desired signal but also includes harmonics and noise signals of other frequencies. The signal received by the receiving antenna needs to be filtered by a filter to remove unnecessary harmonic and noise signals. Therefore, the designed filter must accurately control its upper and lower limit frequencies. And should also consider maintaining high isolation between the passbands of the channels if both transmit and receive channels are present.

The inventor of the present application finds in long-term research and development work that in order to reduce the size of a filter, two or more sets of filter branches with different frequencies are generally combined into a filter, but each set of filter of the existing filter is provided with an output end and an input end, which results in an increase in the number of welding points and taps, and the filter is large in size and high in cost.

Disclosure of Invention

The application provides a communication device and a filter thereof, which are used for solving the problems of the filter in the prior art.

In order to solve the above technical problem, the present application provides a filter, including:

a housing having a first direction and a second direction perpendicular to each other;

a first common chamber and a second common chamber spaced apart on one side of the housing;

the first emission filtering branch circuit is respectively coupled with the first common cavity and the second common cavity and consists of five first emission filtering cavities which are sequentially coupled, and the five first emission filtering cavities further form an inductive cross coupling zero point;

and the second emission filtering branch is respectively coupled with the first common cavity and the second common cavity and consists of five second emission filtering cavities which are sequentially coupled, and the five second emission filtering cavities further form a capacitive cross-coupling zero point.

Wherein the first common cavity is coupled to a first one of the first transmit filter cavities and a first one of the second transmit filter cavities, respectively;

the second common cavity is respectively coupled with a fifth first emission filter cavity and a fifth second emission filter cavity;

the first common cavity, the second common cavity, the five first emission filter cavities, and the five second emission filter cavities are divided into four columns arranged along the second direction.

The second, third and fifth first emission filter cavities are in a row and are sequentially arranged along the first direction;

the first emission filter cavity, the fourth first emission filter cavity and the second common cavity are in a row and are sequentially arranged along the first direction;

the first common cavity, the second emission filter cavity and the fifth emission filter cavity are in a row and are sequentially arranged along the first direction;

the first second emission filter cavity, the third second emission filter cavity and the fourth second emission filter cavity are in a row and are sequentially arranged along the first direction;

the fourth first emission filter cavity is further respectively connected with the first emission filter cavity, the second emission filter cavity, the fifth emission filter cavity and the second common cavity; the fifth first emission filter cavity and the third first emission filter cavity are adjacently arranged; the third second emission filter cavity is further respectively adjacent to the first second emission filter cavity, the fifth second emission filter cavity and the fourth second emission filter cavity.

The first receiving filter branch is arranged on one side of the shell and consists of five first receiving filter cavities which are sequentially coupled, and the five first receiving filter cavities further form an inductive cross-coupling zero point.

The first receiving filter cavity, the second receiving filter cavity and the third receiving filter cavity are arranged in a triangular manner;

a projection of a center of a third one of the first receive filter cavities in the second direction is located between a center of a first one of the first receive filter cavities and a projection of a center of a second one of the first receive filter cavities in the second direction; a projection of a center of a second one of said first receive filter cavities in said first direction is located between a center of a first one of said first receive filter cavities and a projection of a center of a third one of said first receive filter cavities in said first direction;

the third is first receive filter chamber, fourth first receive filter chamber and fifth first receive filter chamber is one and is listed as and follows first direction arranges in proper order.

The third common cavity and the fourth common cavity are arranged on one side of the shell at intervals;

the third emission filtering branch is respectively coupled with the third common cavity and the fourth common cavity and consists of five third emission filtering cavities which are sequentially coupled, and the five third emission filtering cavities further form a capacitive cross-coupling zero point;

the fourth emission filtering branch is respectively coupled with the third common cavity and the fourth common cavity and consists of five fourth emission filtering cavities which are sequentially coupled, and the five fourth emission filtering cavities further form an inductive cross-coupling zero point;

the second receiving and filtering branch is arranged on one side of the shell and consists of five second receiving and filtering cavities which are sequentially coupled, and the five second receiving and filtering cavities further form an inductive cross-coupling zero point;

the second receiving filter cavity and the second first receiving filter cavity are in a row and are sequentially arranged along the second direction.

Wherein the third common cavity is coupled to a first of the third emission filter cavities and a first of the fourth emission filter cavities, respectively;

the fourth common cavity is respectively coupled with a fifth emission filter cavity and a fifth emission filter cavity;

the third common cavity, the fourth common cavity, the five third emission filter cavities, and the five fourth emission filter cavities are divided into four rows arranged along the second direction.

The second receiving filter cavity is adjacent to the second first receiving filter cavity, the first second receiving filter cavity and the third second receiving filter cavity, and the first second receiving filter cavity, the second receiving filter cavity and the third second receiving filter cavity are arranged in a triangular shape;

a projection of a center of a third one of the second receive filter cavities in the second direction is located between a center of a first one of the second receive filter cavities and a projection of a center of a second one of the second receive filter cavities in the second direction; a projection of a center of a second one of said second receive filter cavities in said first direction is located between a center of a first one of said second receive filter cavities and a projection of a center of a third one of said second receive filter cavities in said first direction;

the third is the second receives filter chamber, the fourth the second receives filter chamber and the fifth the second receives filter chamber is one and is listed as and follows the first direction is arranged in proper order.

The first emission filter cavity, the third emission filter cavity and the fourth emission filter cavity are in a row and are sequentially arranged along the first direction;

the third common cavity, the second third emission filter cavity and the fifth third emission filter cavity are in a row and are sequentially arranged along the first direction;

the first emission filter cavity, the fourth emission filter cavity and the fourth common cavity are in a row and are sequentially arranged along the first direction;

the second, third and fifth emission filter cavities are in a row and are sequentially arranged along the first direction;

the first and the third emission filter cavities are further respectively adjacent to the first and the second receiving filter cavities, the third common cavity, the second and the third emission filter cavities; the fourth emission filter cavity is further adjacent to the first emission filter cavity, the third emission filter cavity, the fifth emission filter cavity, the fourth common cavity, the fifth emission filter cavity and the second emission filter cavity.

In order to solve the above technical problem, the present application provides a communication device, which includes a filter and a communication base station, wherein the communication base station transmits and receives radio frequency signals through the filter, and the filter includes any one of the above filters.

Different from the prior art, the first transmitting and filtering branch and the second transmitting and filtering branch are connected through the common cavity so as to realize multi-path transmission of signals and reduce the size of the filter; meanwhile, the two transmitting and filtering branches are provided with cross-coupling zero points, so that a first transmitting signal of the first transmitting and filtering branch is highly isolated from a second transmitting signal of the second transmitting and filtering branch; therefore, the size of the filter can be reduced, and the out-of-band rejection performance of the filter can be improved.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the description of the embodiments are briefly introduced 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 based on these 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 a topology of a first transmit filter branch of the filter of fig. 1;

fig. 3 is a schematic diagram of the topology of the second transmit filter branch of the filter of fig. 1;

FIG. 4 is a schematic diagram of another embodiment of the filter of the present application;

FIG. 5 is a schematic diagram of the topology of the first receive filter branch of the filter of FIG. 4;

FIG. 6 is a diagram showing simulation results of the filter of FIG. 4;

FIG. 7 is a schematic diagram of a filter according to another embodiment of the present application;

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

Detailed Description

In order to make those skilled in the art better understand the technical solution of the present application, a communication device and a filter thereof provided by the present invention are further described in detail below with reference to the accompanying drawings and the detailed description.

The present application provides a filter, as shown in fig. 1, fig. 1 is a schematic structural diagram of an embodiment of the filter of the present application. The filter 10 of the present embodiment includes a housing 11, a first common cavity 121, a second common cavity 122, a first transmitting filter branch 13 and a second transmitting filter branch 14; the housing 11 may be a bottom wall of a filter cavity (not shown) of the filter 10, and the filter cavity of the filter 10 may further include a side wall disposed on the housing 11 and a cover disposed on the side wall.

The housing 11 has a first direction L and a second direction D, and the first direction L of the housing 11 is perpendicular to the second direction D of the housing 11. A first common chamber 121 and a second common chamber 122 spaced apart from each other on one side of the housing 11; the first transmitting and filtering branch 13 is coupled to the first common cavity 121 and the second common cavity 122, and the second transmitting and filtering branch 14 is coupled to the first common cavity 121 and the second common cavity 122, that is, the first transmitting and filtering branch and the second transmitting and filtering branch are connected to the common cavity in this embodiment, so as to implement multi-path transmission of signals, reduce the number of welding points and taps, reduce the cost, and also reduce the size of the filter.

The first emission filtering branch 13 is composed of five first emission filtering cavities 131 coupled in sequence, and the five first emission filtering cavities 131 further form an inductive cross-coupling zero point 132; the second emission filtering branch 14 is composed of five second emission filtering cavities 141 coupled in sequence, and the five first emission filtering cavities 141 further form an inductive cross-coupling zero point 142; the high isolation of the first transmitting signal of the first transmitting and filtering branch circuit and the second transmitting signal of the second transmitting and filtering branch circuit can be realized, and the out-of-band rejection performance and other performances of the filter are improved.

Specifically, the first common cavity 121 is coupled to the first emission filter cavity a11 and the first second emission filter cavity a21, respectively; the second common cavity 122 is coupled to a fifth first emission filter cavity a15 and a fifth second emission filter cavity a25, respectively.

The first common cavity 121, the second common cavity 122, the five first emission filter cavities 131 and the five second emission filter cavities 141 are divided into four columns arranged along the second direction D.

The second first emission filter cavity A12, the third first emission filter cavity A13 and the fifth first emission filter cavity A15 are in a row and are sequentially arranged along the first direction L; the first emission filter cavity a11, the fourth first emission filter cavity a14 and the second common cavity 122 are in a row and are sequentially arranged along the first direction L; the first common cavity 121, the second emission filter cavity a22 and the fifth second emission filter cavity a25 are in a row and are sequentially arranged along the first direction L; the first second emission filter cavity A21, the third second emission filter cavity A23 and the fourth second emission filter cavity A24 are in a row and are sequentially arranged along the first direction L;

the fourth first emission filter cavity a14 is further connected to the first emission filter cavity a11, the second emission filter cavity a22, the fifth second emission filter cavity a25, and the second common cavity 122, respectively; the fifth first emission filter cavity A15 and the third first emission filter cavity A13 are adjacently arranged; the third second emission filter cavity a23 is further disposed adjacent to the first second emission filter cavity a21, the second emission filter cavity a22, the fifth second emission filter cavity a25 and the fourth second emission filter cavity a24, respectively. The first common cavity 121, the second common cavity 122, the five first emission filter cavities 13 and the five second emission filter cavities 14 are regularly distributed, so that the size of the filter 10 can be reduced, a plurality of filters 10 can be produced by the same mold, the cost is reduced, and the stability is high.

As shown in fig. 2, the third first transmit filter cavity a13 is inductively cross-coupled with the fifth first transmit filter cavity a15 to form an inductive cross-coupling null 132.

Specifically, a window may be disposed between the third first transmit filter cavity a13 and the fifth first transmit filter cavity a15, and a metal coupling rib is disposed on the window, so that the third first transmit filter cavity a13 and the fifth first transmit filter cavity a15 realize inductive cross coupling, and form an inductive cross coupling zero, which is equivalent to the inductor L1 shown in fig. 2.

As shown in fig. 3, the first second transmission filter cavity a21 is inductively cross-coupled with the third second transmission filter cavity a23 to form a capacitive cross-coupling zero 142.

Specifically, a window may be disposed between the first second emission filter cavity a21 and the third second emission filter cavity a23, so that the first second emission filter cavity a21 and the third second emission filter cavity a23 implement capacitive cross coupling, and form a capacitive cross coupling zero, which is equivalent to the capacitor C1 shown in fig. 2.

The size of the first common cavity 121, the size of the second common cavity 122, the size of the five first emission filter cavities 13 and the size of the five second emission filter cavities 14 may be the same, that is, they may be arranged in an equidistant distribution, which is convenient for layout and debugging, and improves the uniformity of the filter 10.

In the embodiment, the first transmitting and filtering branch and the second transmitting and filtering branch are connected through the common cavity to realize multi-path transmission of signals, so that the size of the filter can be reduced; meanwhile, the two transmitting and filtering branches of the embodiment are both provided with cross-coupling zero points, so that the first transmitting signal of the first transmitting and filtering branch is highly isolated from the second transmitting signal of the second transmitting and filtering branch; in addition, the filter cavity and the common cavity are regularly distributed, so that the size of the filter can be reduced; can produce a plurality of wave filters through same mould, reduce cost, stability is high.

Optionally, one side of the housing 11 is further provided with a first port (not shown) and a second port (not shown), the first common cavity 121 is connected with the first port, and the second common cavity 122 is connected with the second port. Wherein the first port and the second port may both be taps of the filter 10.

Referring to fig. 4, fig. 4 is a schematic structural diagram of another embodiment of the filter of the present application. The filter 10 of the present embodiment includes a housing 11, a first common cavity 121, a second common cavity 122, a first transmitting filter branch 13, a second transmitting filter branch 14, and a first receiving branch 15. The repeated parts of this embodiment and the above embodiments are not described herein again.

The first receiving filter branch 15, disposed on one side of the housing 11, is composed of five first receiving filter cavities 151 coupled in sequence, and the five first receiving filter cavities 151 further form an inductive cross-coupling zero point 152.

Specifically, the first receiving filter cavity B11 is disposed adjacent to the first second transmitting filter cavity a21 and the second first receiving filter cavity B12, and the first receiving filter cavity B11, the second first receiving filter cavity B12 and the third first receiving filter cavity B13 are disposed in a triangular shape.

The projection of the center of the third first receiving filter cavity B13 in the second direction D is located between the center of the first receiving filter cavity B11 and the projection of the center of the second first receiving filter cavity B12 in the second direction D; the projection of the center of the second first receiving filter cavity B12 in the first direction L is located between the center of the first receiving filter cavity B11 and the projection of the center of the third first receiving filter cavity B13 in the first direction L.

The third first receiving filter cavity B13, the fourth first receiving filter cavity B14 and the fifth first receiving filter cavity B15 are in a row and are sequentially arranged along the first direction L.

As shown in fig. 5, the third first receiving filter cavity B13 is inductively cross-coupled with the third first receiving filter cavity B13 to form an inductive cross-coupling zero 152.

Specifically, a window may be disposed between the third first receiving filter cavity B13 and the fifth first receiving filter cavity B15, and a metal coupling rib is disposed on the window, so that the third first receiving filter cavity B13 and the fifth first receiving filter cavity B15 realize inductive cross coupling, and an inductive cross coupling zero point is formed, which is equivalent to the inductance L2 shown in fig. 5.

The filter comprises two transmitting filter branches and one receiving filter branch, each filter branch comprises a cross coupling zero point, high isolation between a receiving signal and a transmitting signal of the filter can be achieved, and out-of-band rejection performance and other performances of the filter are improved.

In the present embodiment, the bandwidth of the first receiving filtering branch 15 is in the range of 1684MHz-2196MHz, as shown by the frequency band curve 61 in fig. 6. Specifically, the coupling bandwidth between the input end and the first receiving filter cavity B11 ranges from 538Mhz to 602 Mhz; the coupling bandwidth between the first receiving filter cavity B11 and the second first receiving filter cavity B12 ranges from 402Mhz to 451 Mhz; the coupling bandwidth between the first receiving filter cavity B11 and the third first receiving filter cavity B13 ranges from 148Mhz to 169 Mhz; the coupling bandwidth between the second first receiving filter cavity B12 and the third first receiving filter cavity B13 ranges from 279Mhz to 315 Mhz; the coupling bandwidth between the third first receive filter cavity B13 and the fourth first receive filter cavity B14 ranges from 305Mhz-344 Mhz; the coupling bandwidth between the fourth first receiving filter cavity B14 and the fifth first receiving filter cavity B15 ranges from 429Mhz-481 Mhz; the coupling bandwidth between the fifth first receiving filter cavity B15 and the output is in the range 538Mhz-602 Mhz. Therefore, the bandwidth of the first receiving filter branch circuit 15 of the present embodiment is between 1684MHz and 2196MHz, which can meet the design requirement.

Therefore, the resonant frequencies of the first through fifth first receiving filter cavities B11 through B15 are sequentially in the following ranges: 1920Mhz-1922Mhz, 2038Mhz-2040Mhz, 1907Mhz-1909Mhz, 1917Mhz-1919Mhz and 1920Mhz-1922 Mhz.

The bandwidth of the first transmit filter branch 13 is in the range of 2496MHz-2564MHz, as shown by the band curve 62 in fig. 6. Specifically, the coupling bandwidth between the first common cavity 121 and the first emission filter cavity A11 ranges from 64Mhz to 76 Mhz; the coupling bandwidth between the first emission filter cavity a11 and the second first emission filter cavity a12 ranges from 51Mhz to 61 Mhz; the coupling bandwidth between the second first emission filter cavity a12 and the third first emission filter cavity a13 ranges from 35Mhz to 44 Mhz; the coupling bandwidth between the third first emission filter cavity a13 and the fourth first emission filter cavity a14 ranges from 25Mhz to 32 Mhz; the coupling bandwidth between the third first emission filter cavity a13 and the fifth first emission filter cavity a15 ranges from 30Mhz to 38 Mhz; the coupling bandwidth between the fourth first emission filter cavity a14 and the fifth first emission filter cavity a15 ranges from 39Mhz to 48 Mhz; the coupling bandwidth between the fifth first emission filter cavity a15 and the second common cavity 122 ranges from 64Mhz to 76 Mhz. Therefore, the bandwidth of the first transmitting and filtering branch circuit of the embodiment is located between 2496MHz and 2564MHz, and the design requirement can be met.

Therefore, the resonant frequencies of the first to fifth first transmission filter cavities a11 to a15 are in the following ranges in order: 2528Mhz-2530Mhz, 2526Mhz-2528Mhz, 2553Mhz-2555Mhz, 2528Mhz-2530 Mhz.

The bandwidth of the second transmit filter branch 14 is in the range 2616MHz-2684MHz as shown by the band curve 63 in fig. 6. Specifically, the coupling bandwidth between the first common cavity 121 and the first second emission filter cavity a21 ranges from 68Mhz to 80 Mhz; the coupling bandwidth between the first second emission filter cavity A21 and the second emission filter cavity A22 ranges from 41Mhz to 50 Mhz; the coupling bandwidth between the first second emission filter cavity A21 and the third second emission filter cavity A23 ranges from-32 Mhz to-40 Mhz; the coupling bandwidth between the second emission filter cavity A22 and the third second emission filter cavity A23 ranges from 25Mhz to 33 Mhz; the coupling bandwidth between the third second emission filter cavity A23 and the fourth second emission filter cavity A24 ranges from 37Mhz to 46 Mhz; the coupling bandwidth between the fourth second emission filter cavity A24 and the fifth second emission filter cavity A25 ranges from 53Mhz to 64 Mhz; the coupling bandwidth between the fifth second emission filter cavity a25 and the second common cavity 122 ranges from 68Mhz to 80 Mhz. Therefore, the bandwidth of the first transmitting and filtering branch of the embodiment is between 2616MHz and 2684MHz, which can meet the design requirement.

Therefore, the resonant frequencies of the first second emission filter cavity a21 to the fifth second emission filter cavity a25 are sequentially in the following ranges: 2650Mhz-2652Mhz, 2624Mhz-2626Mhz, 2652Mhz-2654Mhz, 2650Mhz-2652Mhz, and 2650Mhz-2652 Mhz.

Continuing to refer to fig. 6, through experimental tests, the bandwidth of the first transmitting and filtering branch 13 of the filter 10 is within a range of 2496MHz-2564MHz, the first transmitting bandwidth suppression satisfies 2572.5MHz > 25dB, and a coupling zero point is formed; the bandwidth of the second emission filtering branch 14 of the filter 10 is in the range of 2616MHz-2684MHz, the first emission bandwidth suppression satisfies 2607MHz > 25dB, and a coupling zero point is formed; the bandwidth of a first receiving filtering branch 15 of the filter 10 is within the range of 1684MHz-2196MHz, the first receiving bandwidth suppression meets 2498MHz & gt 48dB, and a coupling zero point is formed; the first received signal of the first receiving filter branch 15, the first transmitted signal of the first transmitting filter branch 13 and the second transmitted signal of the second transmitting filter branch 14 in the filter 10 are highly isolated from each other.

Referring to fig. 7, fig. 7 is a schematic structural diagram of another embodiment of the filter of the present application. The filter 10 in this embodiment includes a housing 11, a first common cavity 121, a second common cavity 122, a third common cavity 123, a fourth common cavity 124, a first transmitting filter branch 13, a second transmitting filter branch 14, a first receiving filter branch 15, a second receiving filter branch 16, a third transmitting filter branch 17, and a fourth transmitting filter branch 18. The same parts of this embodiment as those of the above embodiment will not be described again.

And a third common chamber 123 and a fourth common chamber 124 spaced apart from each other on one side of the housing 11. The third emission filter branch 17 is respectively coupled to the third common cavity 123 and the fourth common cavity 124, and is composed of five third emission filter cavities 171 coupled in sequence, and the five third emission filter cavities 171 further form a capacitive cross-coupling zero 172. The fourth transmitting and filtering branch 18 is respectively coupled to the third common cavity 123 and the fourth common cavity 124, and is composed of five fourth transmitting and filtering cavities 181 coupled in sequence, and the five fourth transmitting and filtering cavities 181 further form an inductive cross-coupling zero 182. The second receiving filter branch 16 is disposed on one side of the housing 11 and is composed of five second receiving filter cavities 161 coupled in sequence, and the five second receiving filter cavities 161 further form an inductive cross-coupling zero 162. The second receiving filter cavity B22 and the second first receiving filter cavity B12 are aligned in a row and are sequentially arranged along the second direction D.

The third common cavity 123 is coupled to the first third emission-filter cavity a31 and the first fourth emission-filter cavity a41, respectively; the fourth common cavity 134 is coupled to a fifth third emission filter cavity a35 and a fifth fourth emission filter cavity a45, respectively. The third common cavity 123, the fourth common cavity 124, the five third emission filter cavities 171 and the five fourth emission filter cavities 181 are divided into four columns arranged along the second direction D.

The first third emission filter cavity A31, the third emission filter cavity A33 and the fourth third emission filter cavity A34 are in a row and are sequentially arranged along the first direction L; the third common cavity 123, the second third emission filter cavity a32 and the fifth third emission filter cavity a35 are in a row and are sequentially arranged along the first direction L; the first fourth emission filter cavity A41, the fourth emission filter cavity A44 and the fourth common cavity 124 are in a column and are sequentially arranged along the first direction L; the second fourth emission filter cavity a42, the third fourth emission filter cavity a43 and the fifth fourth emission filter cavity a45 are in a column and are sequentially arranged along the first direction L.

The first third emission filter cavity A31 is further disposed adjacent to the first second reception filter cavity B21, the third common cavity 123, the second third emission filter cavity A32 and the third emission filter cavity A33, respectively; the fourth emission filter cavity a44 is further disposed adjacent to the first fourth emission filter cavity a41, the third fourth emission filter cavity a43, the fifth fourth emission filter cavity a45, the fourth common cavity 124, the fifth third emission filter cavity a35 and the second third emission filter cavity a32, respectively.

The second receiving filter cavity B22 is adjacent to the second first receiving filter cavity B12, the first second receiving filter cavity B21 and the third second receiving filter cavity B23, and the first second receiving filter cavity B21, the second receiving filter cavity B22 and the third second receiving filter cavity B23 are arranged in a triangle.

The projection of the center of the third second receiving filter cavity B23 in the second direction D is located between the center of the first second receiving filter cavity B21 and the projection of the center of the second receiving filter cavity B22 in the second direction D; the projection of the centre of the second receiving filter cavity B22 in the first direction L is located between the centre of the first second receiving filter cavity B21 and the projection of the centre of the third second receiving filter cavity B23 in the first direction L.

The third second receiving filter cavity B23, the fourth second receiving filter cavity B24 and the fifth second receiving filter cavity B25 are in a row and are arranged in sequence along the first direction L.

Specifically, the first second receiving filter cavity B21 and the third second receiving filter cavity B23 are inductively cross-coupled to form an inductive cross-coupling zero 162; the first third transmitting filter cavity A31 is capacitively cross-coupled with the third transmitting filter cavity A33 to form a capacitive cross-coupling zero 172; the third fourth transmit filter cavity a43 is inductively cross-coupled to the fifth fourth transmit filter cavity a45 to form an inductive cross-coupling null 182.

In the filter 10 of the present embodiment, the first common cavity 121, the second common cavity 122, the first transmitting filter branch 13, the second transmitting filter branch 14 and the first receiving filter branch 15 are disposed on the left side of the branching line in the housing 11; the third common cavity 123, the fourth common cavity 124, the third transmitting filter branch 16, the fourth transmitting filter branch 17 and the second receiving filter branch 18 are arranged on the right side of the branching line in the shell 11; therefore, the filter cavities and the common cavities in the filter 10 are arranged regularly and symmetrically about the midline of the shell, which is beneficial to layout, and can fully utilize the space of the cavities and reduce the volume of the cavities; in production, a plurality of filters can be manufactured by using the same set of die, so that the cost is saved.

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 this embodiment includes a communication base station 81 and a filter 82, where the filter 82 is disposed at a radio frequency front end of the communication base station 81, so that the communication base station 81 transmits and receives radio frequency signals through the filter 82, and the filter 82 may be the above-mentioned filter 10, and is not described herein again. Therefore, the bandwidth of the first received radio frequency signal of the communication base station 81 is between 1684MHz and 2196MHz, the bandwidth of the first transmitted radio frequency signal is between 2496MHz and 2564MHz, and the bandwidth of the second transmitted radio frequency signal is between 2616MHz and 2684MHz, which can meet the design requirement.

Different from the prior art, the first transmitting and filtering branch and the second transmitting and filtering branch are connected through the common cavity so as to realize multi-path transmission of signals and reduce the size of the filter; meanwhile, the two transmitting and filtering branches are provided with cross coupling zero points, so that the first transmitting signal of the first transmitting and filtering branch is highly isolated from the second transmitting signal of the second transmitting and filtering branch. Therefore, the size of the filter can be reduced, and the out-of-band rejection performance of the filter can be improved.

It is to be understood that the specific embodiments described herein are merely illustrative of the application and are not limiting of the application. In addition, for convenience of description, only a part of structures related to the present application, not all of the structures, are shown in the drawings. 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", "second", etc. in this application are used to distinguish between different objects and not to describe a particular order. 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.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is explicitly and implicitly understood by one skilled in the art that the embodiments described herein can be combined with other embodiments.

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

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

2. The filter of claim 1,

said first common cavity is coupled to a first of said first transmit filter cavities and a first of said second transmit filter cavities, respectively;

3. The filter of claim 2,

4. The filter of claim 3, wherein the filter comprises:

5. The filter of claim 4,

the first receiving filter cavity, the first second transmitting filter cavity and the second first receiving filter cavity are arranged adjacently, and the first receiving filter cavity, the second first receiving filter cavity and the third first receiving filter cavity are arranged in a triangular shape;

6. The filter of claim 5, wherein the filter comprises:

a third common chamber and a fourth common chamber spaced apart from each other on one side of the housing;

7. The filter of claim 6,

the third common cavity is respectively coupled with a first one of the third emission filter cavities and a first one of the fourth emission filter cavities;

8. The filter of claim 7,

9. The filter of claim 8,

the first third emission filter cavity, the third emission filter cavity and the fourth emission filter cavity are in a row and are sequentially arranged along the first direction;

10. A communication device, characterized in that the communication device comprises a filter and a communication base station, the communication base station transceives radio frequency signals through the filter, the filter comprising the filter of any one of the preceding claims 1 to 9.