CN211125971U

CN211125971U - Filter and communication equipment

Info

Publication number: CN211125971U
Application number: CN201922426609.6U
Authority: CN
Inventors: 温世议; 张海峰; 王磊; 李佳琦
Original assignee: Shenzhen Tatfook Technology Co Ltd
Current assignee: Anhui Tatfook Technology Co Ltd
Priority date: 2019-12-27
Filing date: 2019-12-27
Publication date: 2020-07-28
Anticipated expiration: 2029-12-27

Abstract

The application discloses wave filter and communication equipment, this wave filter includes: a housing having a first direction and a second direction perpendicular to each other; a first port disposed on the housing; the first filtering branch is connected with the first port and consists of seven filtering cavities which are sequentially coupled, and the seven filtering cavities of the first filtering branch further form three capacitive cross-coupling zeros; the second filtering branch is connected with the first port and consists of seven filtering cavities which are sequentially coupled, and the seven filtering cavities of the second filtering branch further form three capacitive cross-coupling zeros; the first filtering branch and the second filtering branch are divided into four columns arranged along the first direction. In this way, the first filtering branch and the second filtering branch of the application are connected with the first port, share the first port, reduce the port number of the filter, reduce the cost and reduce the size of the filter.

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

In a mobile communication device, 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 precisely control its bandwidth.

The inventor of the application finds that, in long-term research and development work, a filter in the prior art is provided with at least a first filtering branch and a second filtering branch, and the first filtering branch and the second filtering branch are both required to be provided with input ports and output ports, i.e., the number of the ports of the filter is large, so that the size of the filter is large and the cost of the filter is high.

SUMMERY OF THE UTILITY MODEL

The application provides a filter and communication equipment to solve the technical problem that the filter is large in size and high in cost in the prior art.

An embodiment of the present application provides a filter, including:

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

a first port disposed on the housing;

the first filtering branch is connected with the first port and consists of seven filtering cavities which are sequentially coupled, and the seven filtering cavities of the first filtering branch further form three capacitive cross-coupling zeros;

the second filtering branch is connected with the first port and consists of seven filtering cavities which are sequentially coupled, and the seven filtering cavities of the second filtering branch further form three capacitive cross-coupling zeros;

the first filtering branch and the second filtering branch are divided into four columns arranged along the first direction.

The embodiment of the application further provides communication equipment, the communication equipment comprises an antenna and a radio frequency unit connected with the antenna, and the radio frequency unit comprises the filter for filtering the radio frequency signal.

Different from the situation of the prior art, the first filtering branch and the second filtering branch of the application are connected with the first port and share the first port, so that the number of ports of the filter is reduced, the cost is reduced, and the size of the filter is reduced; in addition, the seven filter cavities of the first filter branch further form three capacitive cross coupling zeros, and the seven filter cavities of the second filter branch further form three capacitive cross coupling zeros which are all capacitive cross coupling, so that the consistency of materials is good, and the debugging of the filter is facilitated; in addition, the first filtering branch and the second filtering branch are divided into four columns arranged along the first direction, namely, the four columns are regularly divided, so that the design of the filter is facilitated, and the size of the filter is further reduced.

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 provided herein;

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

FIG. 3 is a diagram illustrating simulation results of a filter provided herein;

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

FIG. 5 is a schematic diagram of another embodiment of a filter provided herein;

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

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

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

Detailed Description

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

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

Referring to fig. 1, fig. 1 is a schematic structural diagram of an embodiment of a filter provided by the present application, where the filter of the present embodiment includes a housing 11, a first port, a first filtering branch 12 and a second filtering branch 13, the housing 11 has a first direction L1 and a second direction L2 perpendicular to the first direction L1, the first direction L1 may be a length direction of the housing 11, and the second direction L2 may be a width direction of the housing 11.

As shown in fig. 1, the first port is disposed on the housing 11, the first filtering branch 12 is connected to the first port, the first filtering branch 12 is composed of seven filtering cavities coupled in sequence, the seven filtering cavities of the first filtering branch 12 are a first filtering cavity a1, a second filtering cavity a2, a third filtering cavity A3, a fourth filtering cavity A4, a fifth filtering cavity A5, a sixth filtering cavity A6 and a seventh filtering cavity A7., the second filtering branch 13 is connected to the first port, the second filtering branch 13 is composed of seven filtering cavities coupled in sequence, the seven filtering cavities of the second filtering branch 13 are a first filtering cavity B1, a second filtering cavity B2, a third filtering cavity B3, a fourth filtering cavity B4, a fifth filtering cavity B5, a sixth filtering cavity B383 and a seventh filtering cavity B B7., namely, the first filtering cavity 12 and the second filtering cavity B4, the fifth filtering cavity B5, the sixth filtering cavity B383 and the seventh filtering cavity B B7., namely, the first filtering cavity 12 and the second filtering cavity B4, the fifth filtering cavity B7371, the filtering cavity is connected to the first port, the second filtering cavity B7371, the filtering cavity is connected to the second filtering cavity, the filtering cavity is connected to the first port, the second filtering cavity is connected to the second filtering cavity B73713, the filtering cavity is connected to the second filtering cavity, the filtering cavity is connected to the second filtering cavity, the first filtering cavity, the second filtering cavity, the filtering cavity is connected to the second filtering cavity, the second filtering.

Specifically, a first filtering cavity A1 of a first filtering branch 12 and a first filtering cavity B1 of a second filtering branch 13 are connected with a first port, a second filtering cavity A1, a third filtering cavity A1, a fifth filtering cavity A1 and a sixth filtering cavity A1 of the first filtering branch 12 are arranged in a row and are sequentially arranged along a second direction 1, a first filtering cavity A1, a fourth filtering cavity A1 and a seventh filtering cavity A1 of the first filtering branch 12 are arranged in a row and are sequentially arranged along the second direction 1, a first filtering cavity B1, a third filtering cavity B1, a fourth filtering cavity B1 and a fifth filtering cavity B1 of the second filtering branch 13 are arranged in a row and are sequentially arranged along the second direction 1, a second filtering cavity B1, a seventh filtering cavity B1 and a fifth filtering cavity B1 of the second filtering branch 13 are arranged in a row and are arranged along the second direction 1, the first filtering cavity A1, the fourth filtering cavity B1 and the fifth filtering cavity B1 are arranged adjacent to the first filtering cavity A1, the second filtering cavity B1 and the second filtering cavity B1 are arranged adjacent to reduce the filtering cavity utilization rate of the first filtering cavity A1, and the second filtering cavity B1 are respectively, and the second filtering cavity B1, and the adjacent filtering cavity B1, and the second filtering cavity B1, and the second filtering cavity B1 are arranged in a1, and the adjacent filtering cavity B1, and the first filtering cavity B1, and the adjacent filtering cavity B1, and the second filtering.

As shown in fig. 1 and 2, fig. 2 is a schematic diagram of a topology of a first filtering branch provided in the present application. Capacitive cross coupling is respectively performed between the first filter cavity a1 and the third filter cavity A3, between the fourth filter cavity a4 and the seventh filter cavity a7, and between the fifth filter cavity a5 and the seventh filter cavity a7 of the first filter branch 12, so as to form three capacitive cross coupling zeros of the first filter branch 12; the capacitive cross-coupling elements may be flying rods, that is, flying rods are respectively disposed between the first filter cavity a1 and the third filter cavity A3, between the fourth filter cavity a4 and the seventh filter cavity a7, and between the fifth filter cavity a5 and the seventh filter cavity a 7. The first filtering branch 12 realizes zero suppression by setting three capacitive cross-coupling zeros, so that the first filtering branch 12 meets design requirements, and debugging is facilitated.

The cross-coupling zero is also referred to as a transmission zero. The transmission zero is the transmission function of the filter is equal to zero, namely, the electromagnetic energy cannot pass through the network on the frequency point corresponding to the transmission zero, so that the full isolation effect is achieved, the suppression effect on signals outside the passband is achieved, and the high isolation among the multiple passbands can be better achieved.

The housing 11 of this embodiment is further provided with a third port and a fourth port, the seventh filtering cavity a7 of the first filtering branch 12 is connected to the third port, and the seventh filtering cavity B7 of the second filtering branch 13 is connected to the fourth port. The first port, the third port and the fourth port may be taps of the filter, the first port may be an input port, and the third port and the fourth port may be output ports.

In the first filtering branch 12, the coupling bandwidths between the first port and the first filtering cavity a1, the coupling bandwidths of the first filtering cavity a1 and the second filtering cavity a2, the coupling bandwidths of the first filtering cavity a1 and the third filtering cavity A3, the coupling bandwidths of the second filtering cavity a2 and the third filtering cavity A3, the coupling bandwidths of the third filtering cavity A3 and the fourth filtering cavity a4, the coupling bandwidths of the fourth filtering cavity a4 and the fifth filtering cavity A5, the coupling bandwidths of the fourth filtering cavity a4 and the seventh filtering cavity a7, the coupling bandwidths of the fifth filtering cavity A5 and the sixth filtering cavity A6, the coupling bandwidths of the fifth filtering cavity A5 and the seventh filtering cavity a7, the coupling bandwidths of the sixth filtering cavity A6 and the seventh filtering cavity a7, and the coupling bandwidths of the seventh filtering cavity a7 and the coupling bandwidths between the third filtering cavity a7 and the first filtering cavity a are respectively as follows:

26-34MHz、20-27MHz、(-4)-0MHz、13-20MHz、12-18MHz、10-16MHz、(-6)-(-2)MHz、(-9)-(-4)MHz、16-23MHz、19-26MHz、26-34MHz。

the resonant frequencies of the first filter cavity a1 through the seventh filter cavity a7 of the first filter branch 12 are sequentially in the following ranges: 2117-2119MHz, 2116-2118MHz, 2117-2119MHz, 2113-2115MHz, 2118-2120MHz and 2117-2119 MHz. Therefore, the bandwidth of the first filtering branch 12 of this embodiment is within the range of 2104-2135MHz, which can accurately control the bandwidth of the first filtering branch 12, and meet the design requirement of the filter.

As shown in fig. 3, fig. 3 is a schematic diagram of simulation results of the filter provided in the present application. The simulated bandwidth of the first filtering branch 12 in this embodiment is as shown in the frequency band curve 31 in fig. 3, and it can be obtained that the simulated bandwidth of the first filtering branch 12 is within the range of 2104-2135MHz, which meets the design requirement of the filter and can accurately control the bandwidth of the first filtering branch 12. At a frequency of 2100MHz, the rejection of the first filtering branch 12 is greater than 25 dB; when the frequency is 2140MHz, the rejection of the first filtering branch 12 is greater than 25 dB; when the frequency is 1975MHz, the rejection of the first filtering branch 12 is greater than 116dB, so that the out-of-band rejection and other performances of the first filtering branch 12 can be improved.

As shown in fig. 1 and 4, fig. 4 is a schematic diagram of a topology of a second filtering branch provided in the present application. Capacitive cross coupling is respectively performed between the first filtering cavity B1 and the third filtering cavity B3, between the fourth filtering cavity B4 and the sixth filtering cavity B6, and between the fourth filtering cavity B4 and the seventh filtering cavity B7 of the second filtering branch 13, so as to form three capacitive cross coupling zeros of the second filtering branch 13; the capacitive cross-coupling elements may be flying rods, that is, flying rods are respectively disposed between the first filter cavity B1 and the third filter cavity B3, between the fourth filter cavity B4 and the sixth filter cavity B6, and between the fourth filter cavity B4 and the seventh filter cavity B7. The second filtering branch 13 realizes zero suppression by setting three capacitive cross-coupling zeros, so that the second filtering branch 13 meets the design requirement, and is convenient to debug.

In the second filtering branch 13, the coupling bandwidth between the first port and the first filtering cavity B1, the coupling bandwidth between the first filtering cavity B1 and the second filtering cavity B2, the coupling bandwidth between the first filtering cavity B1 and the third filtering cavity B3, the coupling bandwidth between the second filtering cavity B2 and the third filtering cavity B3, the coupling bandwidth between the third filtering cavity B3 and the fourth filtering cavity B4, the coupling bandwidth between the fourth filtering cavity B4 and the fifth filtering cavity B5, the coupling bandwidth between the fourth filtering cavity B4 and the sixth filtering cavity B6, the coupling bandwidth between the fourth filtering cavity B4 and the seventh filtering cavity B7, the coupling bandwidth between the fifth filtering cavity B5 and the sixth filtering cavity B6, the coupling bandwidth between the sixth filtering cavity B6 and the seventh filtering cavity B7, and the coupling bandwidth between the seventh filtering cavity B7 and the fourth filtering cavity B7 are respectively as follows:

30-38MHz、21-28MHz、8-13MHz、13-20MHz、14-21MHz、7-12MHz、(-17)-(-13)MHz、5-10MHz、5-10MHz、22-29MHz、30-38MHz。

the resonant frequencies of the first filter cavity B1 through the seventh filter cavity B7 of the second filter branch 13 are sequentially in the following ranges: 1933 & lt- & gt 1935MHz, 1941 & lt- & gt 1943MHz, 1933 & lt- & gt 1935MHz, 1934 & lt- & gt 1936MHz, 1919 & lt- & gt 1921MHz, 1929 & lt- & gt 1931MHz and 1933 & lt- & gt 1935 MHz. Therefore, the bandwidth of the second filtering branch 13 of the present embodiment is within the range of 1917-1952MHz, and the bandwidth of the second filtering branch 13 can be precisely controlled to meet the design requirement of the filter.

The simulated bandwidth of the second filtering branch 13 in this embodiment is as the band curve 32 in fig. 3, and it can be obtained that the simulated bandwidth of the second filtering branch 13 is within the range of 1917-1952MHz, which meets the design requirement of the filter and can accurately control the bandwidth of the second filtering branch 13. At a frequency of 1915MHz, the rejection of the second filtering branch 13 is greater than 35 dB; when the frequency is 1910MHz, the rejection of the second filtering branch 13 is greater than 45 dB; when the frequency is 1960MHz, the rejection of the second filtering branch 13 is greater than 25dB, so that the out-of-band rejection and other performances of the second filtering branch 13 can be improved.

Referring to fig. 5, fig. 5 is a schematic structural diagram of another embodiment of a filter provided in the present application. The filter of the present embodiment is described on the basis of the filter disclosed above: the filter further comprises a second port, a third filtering branch 14 and a fifth filtering branch 15, the second port and the first port are arranged on the shell 11 at intervals, and the third filtering branch 14 and the fourth filtering branch 15 are both connected with the second port; the third filtering branch 14 is composed of seven filtering cavities coupled in sequence, and the seven filtering cavities of the third filtering branch 14 are a first filtering cavity C1, a second filtering cavity C2, a third filtering cavity C3, a fourth filtering cavity C4, a fifth filtering cavity C5, a sixth filtering cavity C6 and a seventh filtering cavity C7; the fourth filtering branch 15 is composed of seven filtering cavities coupled in sequence, and the seven filtering cavities of the fourth filtering branch 15 are a first filtering cavity D1, a second filtering cavity D2, a third filtering cavity D3, a fourth filtering cavity D4, a fifth filtering cavity D5, a sixth filtering cavity D6 and a seventh filtering cavity D7. Namely, the third filtering branch 14 and the fourth filtering branch 15 are connected with the first port, and share the first port, so that the number of ports of the filter is reduced, the cost is reduced, and the size of the filter is reduced. The seven filter cavities of the third filter branch 14 form three capacitive cross-coupling zeros, and the seven filter cavities of the fourth filter branch 15 form three capacitive cross-coupling zeros which are all capacitive cross-coupling zeros, so that the consistency of materials is good, the debugging of the filter is facilitated, and the isolation between the third filter branch 14 and the fourth filter branch 15 is improved.

Specifically, seven filter cavities of a third filter branch 14 are divided into four rows which are sequentially arranged along a second direction 2, first filter cavities C of the third filter branch 14 are in one row, second filter cavities C of the third filter branch 14 are in one row, third filter cavities C, fourth filter cavities C and seventh filter cavities C of the third filter branch 14 are in one row and sequentially arranged along a first direction 1, the first filter cavities C to the third filter cavities C of the third filter branch 14 are arranged in a triangle, fifth filter cavities C and sixth filter cavities C of the third filter branch 14 are in one row and sequentially arranged along the first direction 1, the fourth filter cavities C of the third filter branch 14 are respectively arranged adjacent to the second filter cavities C, the third filter cavities C, the fifth filter cavities C, the sixth filter cavities C and the seventh filter cavities C, the seventh filter cavities C and the seventh filter cavities C of the third filter branch 14 are respectively arranged adjacent to the second filter cavities C, the third filter cavities C, the sixth filter cavities C and the sixth filter cavities D of the third filter branch 14, the fourth filter cavities C and the fourth filter cavities D are respectively arranged adjacent to the fourth filter cavities C, the fourth filter cavities C and the fourth filter cavities D, the sixth filter cavities C and the fourth filter cavities D, the fourth filter cavities C and the fourth filter cavities 15D are respectively arranged adjacent to the fourth filter cavities 15D, the fourth filter cavities 15 and the fourth filter cavities 15D, the fourth filter cavities of the fourth filter branches 14 are respectively arranged adjacent to the fourth filter cavities.

As shown in fig. 5 and 6, fig. 6 is a schematic diagram of a topology of a third filtering branch provided in the present application. Capacitive cross coupling is respectively performed between the second filtering cavity C2 and the fourth filtering cavity C4, between the fourth filtering cavity C4 and the sixth filtering cavity C6, and between the fourth filtering cavity C4 and the seventh filtering cavity C7 of the third filtering branch 14, so as to form three capacitive cross coupling zeros of the third filtering branch 14; the capacitive cross-coupling elements may be flying rods, that is, flying rods are respectively disposed between the second filter cavity C2 and the fourth filter cavity C4, between the fourth filter cavity C4 and the sixth filter cavity C6, and between the fourth filter cavity C4 and the seventh filter cavity C7. The third filtering branch 14 realizes zero suppression by setting three capacitive cross-coupling zeros, so that the third filtering branch 14 meets design requirements, and debugging is facilitated.

The housing 11 of the present embodiment is further provided with a fifth port and a sixth port, the seventh filtering cavity C7 of the third filtering branch 14 is connected with the fifth port, and the seventh filtering cavity B7 of the fourth filtering branch 15 is connected with the sixth port. The second port, the fifth port and the sixth port may be taps of the filter, the second port may be an input port, and the fifth port and the sixth port may be output ports.

In the third filtering branch 14, the coupling bandwidth between the second port and the first filtering cavity C1, the coupling bandwidth between the first filtering cavity C1 and the second filtering cavity C2, the coupling bandwidth between the second filtering cavity C2 and the third filtering cavity C3, the coupling bandwidth between the second filtering cavity C2 and the fourth filtering cavity C4, the coupling bandwidth between the third filtering cavity C3 and the fourth filtering cavity C4, the coupling bandwidth between the fourth filtering cavity C4 and the fifth filtering cavity C5, the coupling bandwidth between the fourth filtering cavity C4 and the sixth filtering cavity C6, the coupling bandwidth between the fourth filtering cavity C4 and the seventh filtering cavity C7, the coupling bandwidth between the fifth filtering cavity C5 and the sixth filtering cavity C6, the coupling bandwidth between the sixth filtering cavity C6 and the seventh filtering cavity C7, and the coupling bandwidth between the seventh filtering cavity C7 and the fifth filtering cavity C7, respectively, are as follows:

the resonant frequencies of the first filter cavity C1 through the seventh filter cavity C7 of the third filter branch 14 are sequentially in the following ranges: 2117-2119MHz, 2116-2118MHz, 2117-2119MHz, 2113-2115MHz, 2118-2120MHz and 2117-2119 MHz. Therefore, the bandwidth of the third filtering branch 14 of this embodiment is located in the range of 2104-2135MHz, which can accurately control the bandwidth of the third filtering branch 14, and meet the design requirement of the filter.

As shown in fig. 3, fig. 3 is a schematic diagram of simulation results of the filter provided in the present application. The simulated bandwidth of the third filtering branch 14 in this embodiment is as shown in the frequency band curve 31 in fig. 3, and it can be obtained that the simulated bandwidth of the third filtering branch 14 is within the range of 2104-2135MHz, which meets the design requirement of the filter and can accurately control the bandwidth of the third filtering branch 14. At a frequency of 2100MHz, the rejection of the third filtering branch 14 is greater than 25 dB; when the frequency is 2140MHz, the rejection of the third filtering branch 14 is greater than 25 dB; when the frequency is 1975MHz, the rejection of the third filtering branch 14 is greater than 116dB, so that the out-of-band rejection and other performances of the third filtering branch 14 can be improved.

As shown in fig. 5 and 7, fig. 7 is a schematic diagram of a topology of a fourth filtering branch provided in the present application. Capacitive cross coupling is respectively performed between the first filtering cavity D1 and the third filtering cavity D3, between the fourth filtering cavity D4 and the sixth filtering cavity D6, and between the fourth filtering cavity D4 and the seventh filtering cavity D7 of the fourth filtering branch 14, so as to form three capacitive cross coupling zeros of the fourth filtering branch 14; the capacitive cross-coupling elements may be flying rods, that is, flying rods are respectively disposed between the first filter cavity D1 and the third filter cavity D3, between the fourth filter cavity D4 and the sixth filter cavity D6, and between the fourth filter cavity D4 and the seventh filter cavity D7. The fourth filtering branch 14 realizes zero suppression by setting three capacitive cross-coupling zeros, so that the fourth filtering branch 14 meets design requirements, and debugging is facilitated.

In the fourth filtering branch 14, the coupling bandwidth between the second port and the first filtering cavity D1, the coupling bandwidth between the first filtering cavity D1 and the second filtering cavity D2, the coupling bandwidth between the first filtering cavity D1 and the third filtering cavity D3, the coupling bandwidth between the second filtering cavity D2 and the third filtering cavity D3, the coupling bandwidth between the third filtering cavity D3 and the fourth filtering cavity D4, the coupling bandwidth between the fourth filtering cavity D4 and the fifth filtering cavity D5, the coupling bandwidth between the fourth filtering cavity D4 and the sixth filtering cavity D6, the coupling bandwidth between the fourth filtering cavity D4 and the seventh filtering cavity D7, the coupling bandwidth between the fifth filtering cavity D5 and the sixth filtering cavity D6, the coupling bandwidth between the sixth filtering cavity D6 and the seventh filtering cavity D7, and the coupling bandwidth between the sixth filtering cavity D7 are respectively in the following ranges:

the resonant frequencies of the first filter cavity D1 through the seventh filter cavity D7 of the fourth filter branch 14 are sequentially in the following ranges: 1933 & lt- & gt 1935MHz, 1941 & lt- & gt 1943MHz, 1933 & lt- & gt 1935MHz, 1934 & lt- & gt 1936MHz, 1919 & lt- & gt 1921MHz, 1929 & lt- & gt 1931MHz and 1933 & lt- & gt 1935 MHz. Therefore, the bandwidth of the fourth filtering branch 14 of the present embodiment is within the range of 1917-1952MHz, and the bandwidth of the fourth filtering branch 14 can be precisely controlled to meet the design requirement of the filter.

The simulated bandwidth of the fourth filtering branch 14 in this embodiment is as the band curve 32 in fig. 3, and it can be obtained that the simulated bandwidth of the fourth filtering branch 14 is within the range of 1917-1952MHz, which meets the design requirement of the filter and can accurately control the bandwidth of the fourth filtering branch 14. At a frequency of 1915MHz, the rejection of the fourth filtering branch 14 is greater than 35 dB; when the frequency is 1910MHz, the rejection of the fourth filtering branch 14 is greater than 45 dB; when the frequency is 1960MHz, the rejection of the fourth filtering branch 14 is greater than 25dB, so that the out-of-band rejection and other performances of the fourth filtering branch 14 can be improved.

The first filtering branch 12 and the third filtering branch 14 can be both transmitting filtering branches, and the second filtering branch 13 and the fourth filtering branch 15 can be receiving filtering branches.

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 provided in the present application. The communication device of the present embodiment includes an antenna 62 and a radio frequency unit 61. The antenna 62 and the radio frequency unit 61 can be installed on a base station, and can also be installed on objects such as a street lamp; the antenna 62 is connected to a Radio Unit (RRU) 61. The radio frequency unit 61 comprises the filter disclosed in the above embodiments for filtering the radio frequency signal.

In other embodiments, the rf Unit 61 may be integrated with the Antenna 62 to form an Active Antenna Unit (AAU).

It should be noted that some embodiments of the present application refer to the present application as a filter, and may also be referred to as a combiner, that is, a dual-band combiner, and may also be referred to as a duplexer in other embodiments.

The above embodiments are merely examples and are not intended to limit the scope of the present disclosure, and all modifications, equivalents, and flow charts using the contents of the specification and drawings of the present disclosure or those directly or indirectly applied to other related technical fields are intended to be included in the scope of the present disclosure.

Claims

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

a first port disposed on the housing;

2. The filter of claim 1,

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

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

and the third filter cavity of the first filter branch is respectively adjacent to the first filter cavity, the second filter cavity and the fourth filter cavity.

3. The filter of claim 2,

capacitive cross coupling is respectively performed between a first filtering cavity and a third filtering cavity, between a fourth filtering cavity and a seventh filtering cavity and between a fifth filtering cavity and the seventh filtering cavity of the first filtering branch circuit, so as to form three capacitive cross coupling zeros of the first filtering branch circuit;

the bandwidth range of the first filtering branch is as follows: 2104 + 2135 MHz.

4. The filter according to claim 2 or 3,

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

the second filtering cavity, the seventh filtering cavity and the eighth filtering cavity of the second filtering branch are in a row and are sequentially arranged along the second direction;

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

and a sixth filtering cavity of the second filtering branch is respectively adjacent to a fifth filtering cavity, a fourth filtering cavity and a seventh filtering cavity.

5. The filter of claim 4,

capacitive cross coupling is respectively carried out between a first filtering cavity and a third filtering cavity, between a fourth filtering cavity and a sixth filtering cavity and between the fourth filtering cavity and a seventh filtering cavity of the second filtering branch circuit so as to form three inductive cross coupling zeros of the second filtering branch circuit;

the bandwidth range of the second filtering branch is as follows: 1917 and 1952 MHz.

6. The filter of claim 5,

the filter also comprises a third filtering branch, a fourth filtering branch and a second port;

the second port and the first port are arranged at intervals, and the third filtering branch and the fourth filtering branch are both connected with the second port;

the third filtering branch consists of seven filtering cavities which are coupled in sequence, and the seven filtering cavities of the third filtering branch further form three capacitive cross-coupling zeros;

and the seven filter cavities of the fourth filter branch further form three capacitive cross-coupling zeros.

7. The filter of claim 6,

seven filter cavities of the third filter branch circuit are divided into four rows which are sequentially arranged along the second direction;

the first filtering cavities of the third filtering branch are in a row;

the second filtering cavities of the third filtering branch are in a row;

the third filtering cavities, the fourth filtering cavities and the seventh filtering cavities of the third filtering branch are in a row and are sequentially arranged along the first direction, and the first filtering cavities to the third filtering cavities of the third filtering branch are arranged in a triangular shape;

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

a fourth filtering cavity of the third filtering branch is respectively adjacent to the second filtering cavity, the third filtering cavity, the fifth filtering cavity, the sixth filtering cavity and the seventh filtering cavity;

and a seventh filtering cavity of the third filtering branch circuit is adjacent to a sixth filtering cavity of the second filtering branch circuit.

8. The filter of claim 7,

the first filter cavity of the fourth filter branch is adjacent to the first filter cavity of the third filter branch;

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

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

the third filtering cavity, the fourth filtering cavity and the sixth filtering cavity of the fourth filtering branch circuit are linearly arranged;

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

and a seventh filtering cavity of the fourth filtering branch is respectively adjacent to the fourth filtering cavity and the sixth filtering cavity.

9. The filter of claim 8,

inductive cross coupling is respectively performed between a second filtering cavity and a fourth filtering cavity of the third filtering branch, between the fourth filtering cavity and a sixth filtering cavity and between the fourth filtering cavity and a seventh filtering cavity of the third filtering branch so as to form three inductive cross coupling zeros of the third filtering branch;

and the first filtering cavity and the third filtering cavity, the fourth filtering cavity and the sixth filtering cavity and the fourth filtering cavity and the seventh filtering cavity of the fourth filtering branch are inductively and cross-coupled respectively to form three inductive cross-coupling zeros of the fourth filtering branch.

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 radio frequency signals.