CN113054335A

CN113054335A - Communication device and filter

Info

Publication number: CN113054335A
Application number: CN201911380947.9A
Authority: CN
Inventors: 韩军平; 钟志波; 蔡永宏; 屈兵
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, wherein the filter comprises a shell, a first common cavity, a first transmitting filtering branch and a first receiving filtering branch; the shell is provided with a first direction and a second direction which are perpendicular to each other; a first common cavity disposed on the housing; the first emission filtering branch is coupled with the first common cavity and consists of five filtering cavities which are sequentially coupled along a first main emission coupling path; the first receiving filter branch is coupled with the first common cavity, consists of six filter cavities which are sequentially coupled along a first main receiving coupling path, and forms two first inductive cross-coupling zeros. Through the mode, the product complexity can be reduced, and the stability of the filter is improved.

Description

Communication device and filter

Technical Field

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

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 application finds that the existing filter has no common cavity in long-term research and development work, so that the problems of overlarge volume of the cavity, more taps and excessive welding points exist.

Disclosure of Invention

In order to solve the above problems of the prior art filter, the present application provides a communication device and a filter thereof.

In order to solve the technical problem, the application adopts a technical scheme that: providing a filter, wherein the filter comprises a shell, a first common cavity, a first transmitting filter branch and a first receiving filter branch, and the shell is provided with a first direction and a second direction which are perpendicular to each other; a first common chamber disposed on one side of the housing; the first emission filtering branch circuit is coupled with the first common cavity and consists of five filtering cavities which are sequentially coupled along a first main emission coupling path; and the first receiving filter branch is coupled with the first common cavity, consists of six filter cavities which are sequentially coupled along the first main receiving coupling path, and forms two first inductive cross-coupling zeros. The first inductive coupling zero point can realize zero point suppression, so that the indexes can be conveniently debugged; the consistency of materials is improved, the complexity of products is reduced, and the stability of the filter is improved.

The first filter cavity of the first transmitting filter branch and the first filter cavity of the first receiving filter branch are respectively coupled with the first common cavity, and the first filter cavity to the sixth filter cavity of the first receiving filter branch are divided into two rows arranged along the first direction. The six filters are regularly distributed, so that the size of the filter can be reduced.

The first common cavity and the first filtering cavities to the fifth filtering cavities of the first transmitting filtering branch are in a row and are sequentially arranged along the second direction;

the first filtering cavity, the fourth filtering cavity, the fifth filtering cavity and the sixth filtering cavity of the first receiving filtering branch are in a row and are sequentially arranged along the second direction;

the second filter cavity and the third filter cavity of the first receiving filter branch are arranged in a row and are sequentially arranged along the second direction;

the sixth filter cavity of the first receiving filter branch is respectively adjacent to the second filter cavity of the first transmitting filter branch and the fifth filter cavity of the first receiving filter branch;

the fourth filter cavity of the first receiving filter branch is respectively adjacent to the first filter cavity, the third filter cavity and the fifth filter cavity of the first receiving filter branch;

and the first filtering cavity and the third filtering cavity of the first receiving filtering branch circuit and the first filtering cavity and the fourth filtering cavity of the first receiving filtering branch circuit are inductively and cross-coupled respectively to form two first inductive cross-coupling zeros. The first inductive cross coupling zero point can realize zero point suppression, and is convenient for debugging indexes; the consistency of the materials is improved. And reducing the complexity of the product.

The second common cavity is arranged at a distance from the first common cavity;

the second emission filtering branch is coupled with the second common cavity and consists of five filtering cavities which are sequentially coupled along a second main emission coupling path;

the second receiving filter branch is coupled with the second common cavity, consists of six filter cavities which are sequentially coupled along a second main receiving coupling path, and forms two second inductive cross-coupling zero points;

the first filter cavity of the second transmitting filter branch and the first filter cavity of the second receiving filter branch are respectively coupled with the second common cavity, and the first filter cavity to the sixth filter cavity of the second receiving filter branch are divided into two rows arranged along the first direction. The first filtering cavity to the sixth filtering cavity are uniformly distributed, so that the space is saved.

The second common cavity and the first filtering cavity to the fourth filtering cavity of the second emission filtering branch are in a row and are sequentially arranged along the second direction;

the fifth filtering cavity of the second transmitting filtering branch is close to the middle branching line of the shell in the first direction relative to the fourth filtering cavity of the second transmitting filtering branch, so that an included angle between a connecting line of the center of the fifth filtering cavity of the second transmitting filtering branch and the center of the fourth filtering cavity and the middle branching line is an acute angle;

the first filtering cavity, the second filtering cavity, the fifth filtering cavity and the sixth filtering cavity of the second receiving filtering branch are in a row and are sequentially arranged along the second direction;

the third filter cavity and the fourth filter cavity of the second receiving filter branch are arranged in a row and are sequentially arranged along the second direction;

a third filter cavity of the second receiving filter branch is adjacent to the third filter cavity of the first receiving filter branch;

the sixth filter cavity of the second receiving filter branch is respectively adjacent to the fifth filter cavity and the fourth filter cavity of the second receiving filter branch and the second filter cavity of the second transmitting filter branch;

and the second filter cavity and the fifth filter cavity of the second receiving filter branch circuit and the third filter cavity and the fifth filter cavity of the second receiving filter branch circuit are inductively cross-coupled respectively to form two second inductive cross-coupling zeros. The second inductive coupling zero point can realize zero point suppression, and is convenient for debugging indexes; and the method has the effects of improving the consistency of materials, reducing the complexity of products and improving the stability of the filter.

The third receiving filter branch consists of six filter cavities which are sequentially coupled along a third main receiving coupling path and forms a third inductive cross coupling zero point;

the first filter cavity of the third receiving filter branch is coupled with the fifth filter cavity of the second transmitting filter branch, and the first to sixth filter cavities of the third receiving filter branch are divided into three rows arranged along the first direction.

The second filtering cavities and the first filtering cavities of the third receiving filtering branch are in a row and are sequentially arranged along the second direction;

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

the fifth filtering cavities and the fourth filtering cavities of the third receiving filtering branch are in a row and are sequentially arranged along the second direction;

the second filter cavity of the third receiving filter branch is respectively adjacent to the third filter cavity of the second transmitting filter branch, the first filter cavity of the third receiving filter branch, the third filter cavity of the third receiving filter branch and the sixth filter cavity of the third transmitting filter branch;

the first filter cavity of the third receiving filter branch is respectively adjacent to the fourth filter cavity of the second transmitting filter branch, the second filter cavity of the third receiving filter branch and the third filter cavity of the third transmitting filter branch;

a sixth filter cavity of the third receiving filter branch is respectively adjacent to a second filter cavity and a third filter cavity of the third receiving filter branch;

and the third filter cavity and the fifth filter cavity of the third receiving filter branch are inductively cross-coupled to form the third inductive cross-coupling zero point. The zero point suppression can be realized by setting the third inductive cross coupling zero point, so that the indexes can be conveniently debugged; and the method has the effects of improving the consistency of materials, reducing the complexity of products and improving the stability of the filter.

The fourth receiving filter branch consists of six filter cavities which are sequentially coupled along a fourth main receiving coupling path and forms a fourth inductive cross-coupling zero point;

the fourth inductive cross coupling zero point can realize zero point suppression, thereby facilitating the debugging of indexes; and the method has the effects of improving the consistency of materials, reducing the complexity of products and improving the stability of the filter.

The first filter cavity of the fourth receiving filter branch is coupled with the fifth filter cavity of the first transmitting filter branch.

The second filter cavity of the fourth receiving filter branch is close to the midline relative to the first filter cavity of the fourth receiving filter branch, so that an included angle between a connecting line of the center of the second filter cavity of the fourth receiving filter branch and the center of the first filter cavity and the midline is an acute angle;

the projection of the center of the second filter cavity of the fourth receiving filter branch in the first direction is located between the center of the first filter cavity of the fourth receiving filter branch and the projection of the center of the third filter cavity of the third receiving filter branch in the first direction, and the projection of the center of the third filter cavity of the fourth receiving filter branch in the first direction is located between the center of the first filter cavity of the fourth receiving filter branch and the projection of the center of the second filter cavity of the fourth receiving filter branch in the second direction;

the first filtering cavities and the sixth filtering cavities of the fourth receiving filtering branch are in a row and are sequentially arranged along the second direction;

the fifth filter cavity of the fourth receiving filter branch is respectively adjacent to the fifth filter cavity of the second transmitting filter branch, the sixth filter cavity of the fourth receiving filter branch, the third filter cavity and the fourth filter cavity;

a fourth filter cavity of the fourth receiving filter branch is respectively adjacent to a third filter cavity and a fourth filter cavity of the fourth receiving filter branch;

a fourth filter cavity of the third receiving filter branch is respectively adjacent to a sixth filter cavity of the fourth receiving filter branch and a third filter cavity and a fifth filter cavity of the third receiving filter branch;

and the third filter cavity and the fifth filter cavity of the fourth receiving filter branch are inductively cross-coupled to form the fourth inductive cross-coupling zero point.

To solve the above technical problem, the communication device includes an antenna and a radio frequency unit connected to the antenna, where the radio frequency unit includes the filter described in any one of the above items, and is configured to filter a radio frequency signal.

The beneficial effect of this application is: in contrast to the prior art, the present application provides a filter, which includes a housing, a first common cavity, a first transmitting filtering branch and a first receiving filtering branch, where the first receiving filtering branch includes two first inductive cross-coupling zeros; since the filter is provided with the common cavity, the volume of the filter bank cavity becomes small, and further, the number of taps is reduced, and the number of welding points is also reduced.

Drawings

FIG. 1 is a schematic diagram of an embodiment of a filter provided herein;

fig. 2 is a schematic diagram of a topology of a first transmit filter branch provided in the present application;

fig. 3 is a schematic diagram of a topology of a first receiving filter branch provided in the present application;

fig. 4 is a schematic diagram of a topology of a second transmit filter branch provided in the present application;

fig. 5 is a schematic diagram of a topology of a second receiving filter branch provided in the present application;

fig. 6 is a schematic diagram of a topology of a third receiving filter branch provided in the present application;

fig. 7 is a schematic diagram of a topology of a fourth receiving filter branch provided in the present application;

fig. 8 is a schematic diagram of simulation results of a first transmitting branch, a first receiving branch, and a second transmitting branch and a second receiving branch of a filter provided in the present application;

fig. 9 is a schematic diagram of simulation results of a third receiving branch and a fourth receiving branch of the filter provided in the present application;

fig. 10 is a schematic structural diagram of an embodiment of a communication device provided in the present application.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, 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 invention.

The present application provides a filter 91, as shown in fig. 1 to 10, fig. 1 is a schematic structural diagram of an embodiment of the filter 91 provided in the present application; fig. 2 is a schematic diagram of a topology of a first transmit filter branch 30 provided herein; fig. 3 is a schematic diagram of a topology of a first receiving filter branch 40 provided in the present application; fig. 4 is a schematic diagram of a topology of a second transmit filter branch 50 provided herein; fig. 5 is a schematic diagram of a topology of a second receiving filter branch 60 provided in the present application; fig. 6 is a schematic diagram of a topology of a third receiving filter branch 70 provided in the present application; fig. 7 is a schematic diagram of a topology of a fourth receiving filter branch 80 provided in the present application; fig. 8 is a diagram illustrating simulation results of the filter 91 provided in the present application; FIG. 9 is a schematic diagram of another simulation result of the filter 91 provided in the present application; fig. 10 is a schematic structural diagram of an embodiment of a communication device 90 provided in the present application.

One embodiment of the filter 91 includes a housing 10, a first common cavity 20, a first transmit filter branch 30, and a first receive filter branch 40. The housing 10 has a first direction L and a second direction M perpendicular to each other; the first common chamber 20 is disposed on the housing 10; a first emission filter branch 30 coupled to the first common cavity 20 and composed of five filter cavities sequentially coupled along a first main emission coupling path; the first receiving filter branch 40, coupled to the first common cavity 20, is composed of six filter cavities coupled in sequence along the first main receiving coupling path, and forms two first inductive cross-coupling zeros 410.

The housing 10 has a first direction L and a second direction M, and the first direction L of the housing 10 is perpendicular to the second direction M of the housing 10. The first receiving filtering branch 40 comprises six filtering cavities coupled in sequence, and the six filtering cavities further form two first inductive cross-coupling zeros 410, the coupling zeros are also called transmission zeros, the transmission zeros are transmission functions of the filter 91 equal to zero, that is, electromagnetic energy cannot pass through the network at the frequency points corresponding to the transmission zeros, so that a complete isolation effect is achieved, signals outside the pass band are inhibited, high isolation among a plurality of pass bands can be better achieved, and zero inhibition can be achieved by the first inductive cross-coupling zeros 410, so that indexes can be conveniently debugged; the consistency of the materials is improved, the complexity of the product is reduced, and the stability of the filter 91 is improved.

As shown in fig. 2 and 3, the first filter cavity a1 of the first transmitting filter branch 30 and the first filter cavity B1 of the first receiving filter branch 40 are coupled to the first common cavity 20, respectively, and the first filter cavity B1 through the sixth filter cavity B6 of the first receiving filter branch 40 are divided into two columns arranged along the first direction L. Wherein, six filter cavities are regularly distributed, which can reduce the volume of the filter 91.

In an embodiment of the present application, the first filter cavity B1 of the first receiving filter branch 40 is spaced apart from the first common cavity 20, and reinforcing ribs may be disposed between the first common cavity 20 and the first filter cavity B1 of the first receiving filter branch 40 to reinforce the coupling relationship between the first filter cavity B1 of the first receiving filter branch 40 and the first common cavity 20.

The first common cavity 20 and the first to fifth filter cavities a1 to a5 of the first transmitting filter branch 30 are in a row and are sequentially arranged along the second direction M; the first filter cavity B1, the fourth filter cavity B4, the fifth filter cavity B5 and the sixth filter cavity B6 of the first receiving filter branch 40 are in a row and are sequentially arranged along the second direction M; the second filter cavity B2 and the third filter cavity B3 of the first receiving filter branch 40 are arranged in a row and in sequence along the second direction M; the sixth filter cavity B6 of the first receiving filter branch 40 is respectively disposed adjacent to the second filter cavity a2 of the first transmitting filter branch 30 and the fifth filter cavity B5 of the first receiving filter branch 40; the fourth filter cavity B4 of the first receiving filter branch 40 is respectively adjacent to the first filter cavity B1, the third filter cavity B3 and the fifth filter cavity B5 of the first receiving filter branch 40; inductive cross coupling is respectively performed between the first filtering cavity B1 and the third filtering cavity B3 of the first receiving filtering branch 40 and between the first filtering cavity B1 and the fourth filtering cavity B4 of the first receiving filtering branch 40 to form two first inductive cross coupling zero points 410, so that zero point suppression can be realized, and indexes can be conveniently debugged; the consistency of the materials is improved, and the complexity of the product is reduced.

Wherein the first through fifth filter cavities a 1-a 5 of the first transmitting filter branch 30 may have the same size as the first common cavity 20. That is, 6 filter cavities can be distributed at equal intervals, so that the layout and debugging are facilitated, and the consistency of the filter 91 is improved.

The sizes of the first filtering cavity B1 to the sixth filtering cavity B6 of the first receiving filtering branch 40 can be the same, that is, 6 filtering cavities can be equidistantly distributed, so that the layout and debugging are facilitated, and the consistency of the filter 91 is improved.

Optionally, the housing 10 is further provided with a first port (not shown), a second port (not shown) and a third port (not shown), the first common cavity 20 is connected with the first port, and the fifth filter cavity a5 of the first transmitting filter branch 30 and the sixth filter cavity B6 of the first receiving filter branch 40 are connected with the second port and the third port, respectively. Wherein the first port, the second port and the third port are all taps.

The bandwidth of the first transmit filter branch 30 is: 935MHz-960MHz, and specifically the coupling bandwidth between the first port and the first common cavity 20 is 148MHz-169 KHz; the coupling bandwidth between the first common cavity 20 and the first filter cavity a1 of the first transmit filter branch 30 is 50KHz-60 KHz; the coupling bandwidth between the first filter cavity A1 of the first transmitting filter branch 30 and the second filter cavity A2 of the first transmitting filter branch 30 is 14KHz-20 KHz; the coupling bandwidth between the second filter cavity a2 of the first transmitting filter branch 30 and the third filter cavity A3 of the first transmitting filter branch 30 is 12KHz-17 KHz; the coupling bandwidth between the third filter cavity A3 of the first transmitting filter branch 30 and the fourth filter cavity a4 of the first transmitting filter branch 30 is 12KHz-17 KHz; the coupling bandwidth between the fourth filter cavity a4 of the first transmitting filter branch 30 and the fifth filter cavity a5 of the first transmitting filter branch 30 is 17KHz-23 KHz; the coupling bandwidth between the fifth filter cavity a5 of the first transmit filter branch 30 and the second port is: 21KHz-27 KHz. Therefore, the bandwidth of the first transmitting and filtering branch of the filter 91 of this embodiment is located between 935MHz and 960MHz, which can meet the design requirement.

Therefore, the resonant frequencies of the first filter cavity a1 to the fifth filter cavity a5 of the first transmitting filter branch 30 are sequentially in the following ranges: 922MHz-924MHz, 947MHz-949MHz, 846MHz-948MHz and 846MHz-948 MHz.

The bandwidth of the first receive filtering branch 40 lies in the range of 887MHz-919 MHz. Specifically, the coupling bandwidth between the first common cavity 20 and the first filter cavity B1 of the first receiving filter branch 40 is 16MHz-22MHz, and the coupling bandwidth between the first filter cavity B1 of the first receiving filter branch 40 and the third filter cavity B3 of the first receiving filter branch 40 is 10MHz-15 MHz; the coupling bandwidth between the first filter cavity B1 of the first receiving filter branch 40 and the fourth filter cavity B4 of the first receiving filter branch 40 is 0MHz-2 MHz; the coupling bandwidth between the second filter cavity B2 of the first receiving filter branch 40 and the third filter cavity B3 of the first receiving filter branch 40 is 12MHz-17 MHz; the coupling bandwidth between the third filter cavity B3 of the first receiving filter branch 40 and the fourth filter cavity B4 of the first receiving filter branch 40 is 15MHz-21 MHz; the coupling bandwidth between the fourth filter cavity B4 of the first receiving filter branch 40 and the fifth filter cavity B5 of the first receiving filter branch 40 is 16MHz-22 MHz; the coupling bandwidth between the fifth filter cavity B5 of the first receiving filter branch 40 and the sixth filter cavity B6 of the first receiving filter branch 40 is 22MHz-29 MHz; the coupling bandwidth between the sixth filter cavity B6 of the first receive filter branch 40 and the third port is 28MHz-35 MHz.

Therefore, the bandwidth of the first receiving and filtering branch 40 of the filter 91 of the present embodiment is located between 935MHz and 960MHz, which can meet the design requirement.

Therefore, the resonant frequencies of the first filter cavity B1 through the sixth filter cavity B6 of the first receiving filter branch 40 are sequentially located in the following ranges: 901MHz-903MHz, 912MHz-914MHz, 902MHz-904MHz, 901MHz-903MHz, and 902MHz-904 MHz.

The filter 91 further includes: a second common cavity 23, a second transmitting filter branch 50 and a second receiving filter branch 60, wherein the second common cavity 23 is spaced apart from the first common cavity 20; the second transmitting filter branch 50 is coupled with the second common cavity 23 and consists of five filter cavities which are sequentially coupled along a second main transmitting coupling path; the second receiving filter branch 60 is coupled to the second common cavity 23, and is composed of six filter cavities sequentially coupled along the second main receiving coupling path, and forms two second inductive cross-coupling zeros 610; the first filter cavity D1 of the second transmitting filter branch 50 and the first filter cavity D1 of the second receiving filter branch 60 are respectively coupled to the second common cavity 23, and the first filter cavity D1 through the sixth filter cavity D6 of the second receiving filter branch 60 are divided into two columns arranged along the first direction L.

As shown in fig. 3 and 4, the second common cavity 23, the first filter cavity C1 to the fourth filter cavity C4 of the second transmitting filter branch 50 are in a row and are arranged in sequence along the second direction M; the fifth filter cavity C5 of the second transmitting filter branch 50 is close to the midline of the housing 10 in the first direction L relative to the fourth filter cavity C4 of the second transmitting filter branch 50, so that an included angle between the center of the fifth filter cavity C5 of the second transmitting filter branch 50 and the central connecting line and the midline of the fourth filter cavity C4 is an acute angle; the first filter cavity D1, the second filter cavity D2, the fifth filter cavity D5 and the sixth filter cavity D6 of the second receiving filter branch 60 are in a row and are sequentially arranged along the second direction M; the third filtering cavity D3 and the fourth filtering cavity D4 of the second receiving filtering branch 60 are arranged in a row and in sequence along the second direction M; the third filter cavity D3 of the second receiving filter branch 60 is disposed adjacent to the third filter cavity B3 of the first receiving filter branch 40; the sixth filtering cavity D6 of the second receiving filtering branch 60 is respectively adjacent to the fifth filtering cavity D5, the fourth filtering cavity D4 of the second receiving filtering branch 60 and the second filtering cavity C2 of the second transmitting filtering branch 50; the inductive cross-coupling is respectively performed between the second filter cavity D2 and the fifth filter cavity D5 of the second receiving filter branch 60, and between the third filter cavity D3 and the fifth filter cavity D5 of the second receiving filter branch 60, so as to form two second inductive cross-coupling zeros 610.

The second inductive cross-coupling zero point 610 can realize zero point suppression, thereby facilitating the debugging of indexes; and has the effects of improving material consistency, reducing the complexity of the product and improving the stability of the filter 91.

Optionally, the housing 10 is further provided with a fourth port (not shown) and a fifth port (not shown), the second common cavity 23 is connected with the fourth port, and the first filter cavity D1 of the second receiving filter branch 60 and the first filter cavity C1 of the second transmitting filter branch 50 are connected with the fifth port and the sixth port, respectively. Wherein the fourth port, the fifth port and the sixth port may all be taps of the filter 91.

The bandwidth of the second transmit filter branch 50 is: in the range of 935MHz to 960 MHz. Specifically, the coupling bandwidth between the fourth port and the second common cavity 23 ranges from 148MHz to 169 MHz; the coupling bandwidth between the second common cavity 23 and the first filtering cavity C1 of the second transmitting filtering branch 50 is 50MHz-60 MHz; the coupling bandwidth between the first filter cavity C1 of the second transmitting filter branch 50 and the second filter cavity C2 of the second transmitting filter branch 50 is 15MHz-21 MHz; the coupling bandwidth between the second filter cavity C2 of the second transmitting filter branch 50 and the third filter cavity C3 of the second transmitting filter branch 50 is 12MHz-17 MHz; the coupling bandwidth between the third filter cavity C3 of the second transmitting filter branch 50 and the fourth filter cavity C4 of the second transmitting filter branch 50 is 12MHz-17 MHz; the coupling bandwidth between the fourth filter cavity C4 of the second transmitting filter branch 50 and the fifth filter cavity C5 of the second transmitting filter branch 50 is 17MHz-23 MHz; the coupling bandwidth between the fifth filter cavity C5 and the fifth port of the second transmit filter branch 50 is 21MHz-23 MHz.

Therefore, the resonant frequencies of the first filter cavity C1 to the fifth filter cavity C5 of the second transmitting filter branch 50 are sequentially located in the following ranges: 922MHz-924MHz, 947MHz-949MHz, 946MHz-948MHz and 946MHz-948 MHz.

The bandwidth of the second receive filtering branch 60 lies in the range of 887MHz-919 MHz. Specifically, the coupling bandwidth between the second common cavity 23 and the first filtering cavity D1 of the second receiving filtering branch 60 is 19MHz-25MHz, and the coupling bandwidth between the first filtering cavity D1 of the second receiving filtering branch 60 and the second filtering cavity D2 of the second receiving filtering branch 60 is 16MHz-22 MHz; the coupling bandwidth between the second filter cavity D2 of the second receiving filter branch 60 and the third filter cavity D3 of the second receiving filter branch 60 is 0MHz-4 MHz; the coupling bandwidth between the second filter cavity D2 of the second receiving filter branch 60 and the fourth filter cavity D4 of the second receiving filter branch 60 is 12MHz-17 MHz; the coupling bandwidth between the third filter cavity D3 of the second receiving filter branch 60 and the fourth filter cavity D4 of the second receiving filter branch 60 is 7MHz-12 MHz; the coupling bandwidth between the fourth filter cavity D4 of the second receiving filter branch 60 and the fifth filter cavity D5 of the second receiving filter branch 60 is 13MHz-19 MHz; the coupling bandwidth between the fifth filter cavity D5 of the second receiving filter branch 60 and the sixth filter cavity D6 of the second receiving filter branch 60 is 23MHz-30 MHz; the coupling bandwidth between the sixth filter cavity D6 and the fifth port of the second receiving filtering branch 60 is 28MHz-35 MHz.

In addition, the filter 91 further comprises a third receiving filter branch 70, which is composed of six filter cavities sequentially coupled along a third main receiving coupling path and forms a third inductive cross-coupling zero 710; the first filter cavity E1 of the third receiving filter branch 70 is coupled to the fifth filter cavity C5 of the second transmitting filter branch 50, and the first through sixth filter cavities E1 through E6 of the third receiving filter branch 70 are divided into three columns arranged along the first direction L.

The second filter cavity E2 and the first filter cavity E1 of the third receiving filter branch 70 are in a row and are sequentially arranged along the second direction M; the sixth filtering cavity E6 and the third filtering cavity E3 of the third receiving filtering branch 70 are in a row and are sequentially arranged along the second direction M; the fifth filter cavity E5 and the fourth filter cavity E4 of the third receiving filter branch 70 are in a row and are sequentially arranged along the second direction M; the second filter cavity E2 of the third receiving filter branch 70 is respectively adjacent to the third filter cavity C3 of the second transmitting filter branch 50, the first filter cavity E1 of the third receiving filter branch 70, the third filter cavity E3 and the sixth filter cavity E6; the first filter cavity E1 of the third receiving filter branch 70 is respectively adjacent to the fourth filter cavity C4 of the second transmitting filter branch 50, the second filter cavity E2 of the third receiving filter branch 70 and the third filter cavity E3; the sixth filter cavity E6 of the third receiving filter branch 70 is respectively adjacent to the second filter cavity E2 and the third filter cavity E3 of the third receiving filter branch 70; the third filter cavity E3 and the fifth filter cavity E5 of the third receiving filtering branch 70 are inductively cross-coupled to form a third inductive cross-coupling zero 710.

The setting of the third inductive cross-coupling zero 710 can realize zero suppression, which is convenient for debugging indexes; and has the effects of improving material consistency, reducing the complexity of the product and improving the stability of the filter 91.

Optionally, the housing 10 is further provided with a sixth port, and the sixth port is connected with the sixth filter cavity E6 of the third receiving filter branch 70. Wherein the sixth port may be a tap of the filter 91.

As shown in fig. 6, the bandwidth of the third receive filtering branch 70 is in the range of 887MHz-919 MHz. Specifically, the coupling bandwidth between the fifth filter cavity C5 of the second transmitting filter branch 50 and the first filter cavity E1 of the third receiving filter branch 70 is 32MHz-40 MHz; the coupling bandwidth between the first filter cavity E1 of the third receiving filter branch 70 and the second filter cavity E2 of the third receiving filter branch 70 is 24MHz-31 MHz; the coupling bandwidth between the second filter cavity E2 of the third receiving filter branch 70 and the third filter cavity E3 of the third receiving filter branch 70 is 16MHz-22 MHz; the coupling bandwidth between the third filter cavity E3 of the third receiving filter branch 70 and the fourth filter cavity E4 of the third receiving filter branch 70 is 14MHz-20 MHz; the coupling bandwidth between the third filter cavity E3 of the fourth receiving filter branch 80 and the fifth filter cavity E5 of the third receiving filter branch 70 is 15MHz-21 MHz; the coupling bandwidth between the fifth filter cavity E5 of the third receiving filter branch 70 and the sixth filter cavity E6 of the third receiving filter branch 70 is 24MHz-31 MHz; the coupling bandwidth between the sixth filter cavity E6 and the sixth port of the third receiving filtering branch 70 is 32MHz-40 MHz.

Therefore, the resonant frequencies of the first filter cavity E1 through the sixth filter cavity E6 of the third receiving filter branch 70 are sequentially located in the following ranges: 902MHz-904MHz, 901MHz-903MHz, 908MHz-910 MHz; 901MHz-903MHz, 902MHz-904MHz and 902MHz-904 MHz.

The filter 91 further comprises a fourth receiving filtering branch 80, the fourth receiving filtering branch 80 is composed of six filtering cavities coupled in sequence along a fourth main receiving coupling path, and a fourth inductive cross-coupling zero 810 is formed; the first filter cavity F1 of the fourth receiving filter branch 80 is coupled to the fifth filter cavity a5 of the first transmitting filter branch 30.

As shown in fig. 7, the second filter cavity F2 of the fourth receiving filter branch 80 is close to the bisector with respect to the first filter cavity F1 of the fourth receiving filter branch 80, so that an included angle between a connecting line of the center of the second filter cavity F2 of the fourth receiving filter branch 80 and the center of the first filter cavity and the bisector is an acute angle;

the first filter cavity F1 to the third filter cavity F3 of the fourth receiving filter branch 80 are arranged in a triangle, a projection of a center of the second filter cavity F2 of the fourth receiving filter branch 80 in the first direction L is located between a center of the first filter cavity F1 of the fourth receiving filter branch 80 and a projection of a center of the third filter cavity F3 in the first direction L, and a projection of a center of the third filter cavity F3 of the fourth receiving filter branch 80 in the first direction L is located between a center of the first filter cavity F1 of the fourth receiving filter branch 80 and a projection of a center of the second filter cavity F2 in the second direction M;

the first filter cavity F1 and the sixth filter cavity F6 of the fourth receiving filter branch 80 are in a row and are sequentially arranged along the second direction M;

the fifth filter cavity F5 of the fourth receiving filter branch 80 is respectively adjacent to the fifth filter cavity C5 of the second transmitting filter branch 50, the sixth filter cavity F6 of the fourth receiving filter branch 80, the third filter cavity F3 and the fourth filter cavity F4;

the fourth filter cavity F4 of the fourth receiving filter branch 80 is respectively adjacent to the third filter cavity F3 and the fourth filter cavity F4 of the fourth receiving filter branch 80;

the fourth filter cavity F4 of the third receiving filter branch 70 is respectively adjacent to the sixth filter cavity F6 of the fourth receiving filter branch 80 and the third filter cavity E3 and the fifth filter cavity E5 of the third receiving filter branch 70;

the third filter cavity F3 and the fifth filter cavity F5 of the fourth receiving filtering branch 80 are inductively cross-coupled to form a fourth inductive cross-coupling zero 810.

The fourth inductive cross-coupling zero 810 can realize zero suppression, thereby facilitating the debugging of indexes; and has the effects of improving material consistency, reducing the complexity of the product and improving the stability of the filter 91.

Optionally, the housing 10 is further provided with a seventh port, and the seventh port is connected with the sixth filtering cavity F6 of the fourth receiving filtering branch 80; wherein the seventh port may be a tap of the filter 91.

The bandwidth of the fourth receive filter branch 80 is in the range of 887Mhz-919 Mhz. Specifically, the coupling bandwidth between the second common cavity 23 and the first filtering cavity F1 of the fourth receiving filtering branch 80 ranges from 32MHz to 40 MHz; the coupling bandwidth between the first filter cavity F1 of the fourth receiving filter branch 80 and the second filter cavity F2 of the fourth receiving filter branch 80 is in the range of 24MHz-31 MHz; the coupling bandwidth between the second filter cavity F2 of the fourth receiving filter branch 80 and the third filter cavity F3 of the fourth receiving filter branch 80 is in the range of 16MHz-22 MHz; the coupling bandwidth between the third filter cavity F3 of the fourth receiving filter branch 80 and the fourth filter cavity F4 of the fourth receiving filter branch 80 is in the range of 14MHz-20 MHz; the coupling bandwidth between the third filter cavity F3 of the fourth receiving filter branch 80 and the fifth filter cavity F5 of the fourth receiving filter branch 80 is in the range of 15MHz-21 MHz; the coupling bandwidth between the fifth filter cavity F5 of the fourth receiving filter branch 80 and the sixth filter cavity F6 of the fourth receiving filter branch 80 is in the range of 24MHz-31 MHz; the coupling bandwidth between the sixth filter cavity F6 and the seventh port of the fourth receive filter branch 80 is 32MHz-40 MHz.

The resonant frequencies of the first filter cavity F1 through the sixth filter cavity F6 of the fourth receiving filter branch 80 are thus in the following ranges in sequence: 902MHz-904MHz, 901MHz-903MHz, 908MHz-910 MHz; 901MHz-903MHz, 902MHz-904MHz and 902MHz-904 MHz.

Fig. 8 is a schematic diagram of simulation results of the first transmitting filter branch 30, the second transmitting filter branch 50, the first receiving filter branch 40 and the second receiving filter branch 60 of the filter 91 according to the present application, and experimental tests show that bandwidths of the first transmitting filter branch 30 and the second transmitting filter branch 50 of the filter 91 are 935MHz-960 MHz; the bandwidths of the first receive filter branch 40 and the second receive filter branch 60 are located at 887MHz-919MHz, as shown by the band curve 100. The first receiving filtering branch 40 and the second receiving filtering branch 60 of the filter 91 of the present application respectively include 2 inductive cross-coupling zeros; here, the frequency of zero point P is 945MHz, and the bandwidth suppression of zero point P is greater than 81dB at this time, so that the performance of filter 91, such as out-of-band suppression, can be improved.

Fig. 9 is a schematic diagram of simulation results of the third receiving filtering branch 70 and the fourth receiving filtering branch 80 of the filter 91 according to the present application, and through experimental tests, bandwidths of the third receiving filtering branch 70 and the fourth receiving filtering branch 80 are located between 887MHz and 919MHz, as shown by the frequency band curve 110. The third receiving filtering branch 70 and the fourth receiving filtering branch 80 respectively include two inductive cross-coupling zeros; the frequency at the Q zero point is 937MHz, and the bandwidth rejection at the N zero point is greater than 81dB, so that the out-of-band rejection performance of the filter 91 can be improved.

As shown in fig. 10, the present application further provides a communication device 90, where the communication device 90 includes an antenna 93 and a radio frequency unit connected to the antenna 93, the radio frequency unit includes a filter 91, and the filter 91 is configured to filter a radio frequency signal.

The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes performed by the present specification and drawings, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.

Claims

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

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

a first common cavity disposed on the housing;

the first emission filtering branch circuit is coupled with the first common cavity and consists of five filtering cavities which are sequentially coupled along a first main emission coupling path;

and the first receiving filter branch is coupled with the first common cavity, consists of six filter cavities which are sequentially coupled along a first main receiving coupling path, and forms two first inductive cross-coupling zeros.

2. The filter of claim 1, wherein the first filter cavities of the first transmitting filter branch and the first filter cavities of the first receiving filter branch are respectively coupled to the first common cavity, and the first to sixth filter cavities of the first receiving filter branch are divided into two columns arranged along the first direction.

3. The filter of claim 2,

the first common cavity and the first filtering cavity to the fifth filtering cavity of the first transmitting filtering branch are in a row and are sequentially arranged along the second direction;

and the first filtering cavity and the third filtering cavity of the first receiving filtering branch circuit and the first filtering cavity and the fourth filtering cavity of the first receiving filtering branch circuit are inductively and cross-coupled respectively to form two first inductive cross-coupling zeros.

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

a second common chamber spaced from the first common chamber;

the first filter cavity of the second transmitting filter branch and the first filter cavity of the second receiving filter branch are respectively coupled with the second common cavity, and the first filter cavity to the sixth filter cavity of the second receiving filter branch are divided into two rows arranged along the first direction.

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

the second common cavity and the first filtering cavity to the fourth filtering cavity of the second transmitting filtering branch are in a row and are sequentially arranged along the second direction;

and the second filter cavity and the fifth filter cavity of the second receiving filter branch circuit and the third filter cavity and the fifth filter cavity of the second receiving filter branch circuit are inductively cross-coupled respectively to form two second inductive cross-coupling zeros.

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

7. The filter of claim 6,

and the third filter cavity and the fifth filter cavity of the third receiving filter branch are inductively cross-coupled to form the third inductive cross-coupling zero point.

8. The filter of claim 7, wherein the filter comprises:

the fourth receiving filter branch consists of six filter cavities which are sequentially coupled along a fourth main receiving coupling path and forms a fourth inductive cross coupling zero point;

9. The filter of claim 8,

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