CN211125970U - Communication device and filter thereof - Google Patents

Abstract

The application discloses a communication device and a filter thereof. The filter includes: a housing having a first direction and a second direction perpendicular to each other; and the filtering branch circuit is arranged on the shell and consists of eight filtering cavities which are sequentially coupled, and the eight filtering cavities of the filtering branch circuit form three inductive cross-coupling zeros. By means of the mode, the type of materials can be reduced, the complexity of the filter is reduced, and the stability of the filter is 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 application finds that the existing filter is provided with capacitive cross coupling and inductive cross coupling at the same time in long-term research and development work, and the product complexity is high due to the fact that materials of the capacitive cross coupling are different from materials of the inductive cross coupling, and the types of the materials needed by the filter are multiple.

SUMMERY OF THE UTILITY MODEL

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

To solve the above problem, an embodiment of the present application provides a filter, including:

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

and the eight filter cavities of the filter branch circuit form three inductive cross coupling zero points, and are divided into two rows arranged along the second direction.

Optionally, the first filter cavity, the fourth filter cavity, the sixth filter cavity and the eighth filter cavity of the filter branch are in a row and are sequentially arranged along the first direction;

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

Optionally, the third filter cavity of the filter branch is further disposed adjacent to the first filter cavity and the fourth filter cavity, and the seventh filter cavity of the filter branch is further disposed adjacent to the fifth filter cavity and the sixth filter cavity;

a third filter cavity of the filter branch circuit is intersected with the second filter cavity;

and the eighth filtering cavity and the seventh filtering cavity of the filtering branch are arranged in an intersecting manner.

Optionally, the first filter cavity and the third filter cavity, the third filter cavity and the fifth filter cavity, and the sixth filter cavity and the eighth filter cavity of the filter branch are inductively cross-coupled, respectively, to form three inductive cross-coupling zeros.

Optionally, the first side of the housing is further provided with a first port and a second port, the first filtering cavity of the filtering branch is connected to the first port, and the eighth filtering cavity of the filtering branch is connected to the second port.

Optionally, the bandwidth of the filtering branch is in the range of 812Mhz-881 Mhz.

In order to solve the above problem, an embodiment of the present application provides a communication device, where the communication device includes an antenna and a radio frequency unit connected to the antenna, the radio frequency unit includes a filter, the filter is configured to filter a radio frequency signal, and the filter includes:

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

and the eight filter cavities of the filter branch circuit form three inductive cross coupling zero points, and are divided into two rows arranged along the second direction.

Optionally, the first filter cavity, the fourth filter cavity, the sixth filter cavity and the eighth filter cavity of the filter branch are in a row and are sequentially arranged along the first direction;

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

the third filter cavity of the filter branch is further arranged adjacent to the first filter cavity and the fourth filter cavity, and the seventh filter cavity of the filter branch is further arranged adjacent to the fifth filter cavity and the sixth filter cavity;

a third filter cavity of the filter branch circuit is intersected with the second filter cavity;

and the eighth filtering cavity and the seventh filtering cavity of the filtering branch are arranged in an intersecting manner.

Optionally, the first filter cavity and the third filter cavity, the third filter cavity and the fifth filter cavity, and the sixth filter cavity and the eighth filter cavity of the filter branch are inductively cross-coupled, respectively, to form three inductive cross-coupling zeros.

Optionally, the bandwidth of the filtering branch is in the range of 812Mhz-881 Mhz.

Compared with the prior art, the eight filter cavities of the filter branch circuit form three inductive cross coupling zero points, zero point inhibition can be realized, debugging indexes are convenient, the eight filter cavities are inductive cross coupling zero points, inductive cross coupling elements are the same, the types of materials are reduced, the complexity of the filter is reduced, and the stability of the filter is improved. In addition, eight filter chambers of the filter branch are divided into two rows arranged along the second direction, namely the eight filter chambers of the filter branch are regularly arranged and compactly arranged, and the size of the filter is 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 according to the present application;

FIG. 2 is a schematic diagram of the topology of the filtering branch of FIG. 1;

FIG. 3 is a diagram showing simulation results of the filter of FIG. 1;

fig. 4 is a schematic structural diagram of an embodiment of a communication device of the present application.

Detailed Description

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

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

The 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 of the present embodiment includes a housing 11 and a filter branch 12, the filter branch 12 may be a receiving filter branch or a transmitting filter branch, the housing 11 has a first direction L and a second direction D, the first direction L of the housing 11 is perpendicular to the second direction D of the housing 11, the first direction L of the housing 11 may be a length direction of the housing 11, and the second direction D of the housing 11 may be a width direction of the housing 11.

The filtering branch 12 is arranged on the shell 11 and consists of eight filtering cavities which are sequentially coupled, and the eight filtering cavities of the filtering branch 12 further form three inductive cross-coupling zero points, so that zero point suppression can be realized, and indexes can be conveniently debugged; all inductive cross coupling zero points are the same, inductive cross coupling elements are the same, the types of materials are reduced, the complexity of the filter is reduced, and the stability of the filter is improved.

As shown in fig. 1, the eight filter cavities 121 of the filter branch 12 are divided into two rows arranged along the second direction D, that is, the eight filter cavities of the filter branch 12 are regularly arranged and compactly arranged, so as to reduce the volume of the filter, the eight filter cavities of the filter branch 12 are a first filter cavity a1, a second filter cavity a2, a third filter cavity A3, a fourth filter cavity a4, a fifth filter cavity a5, a sixth filter cavity A6, a seventh filter cavity a7 and an eighth filter cavity A8., wherein the first filter cavity a1, the fourth filter cavity a4, the seventh filter cavity a7 and the eighth filter cavity A8 are arranged in a row and sequentially arranged along the first direction L, the second filter cavity a2, the third filter cavity A3, the fifth filter cavity a5 and the sixth filter cavity A6 are arranged in a row and sequentially arranged along the first direction D, so as to reduce the volume of the filter by using the eight filter cavities L in order.

The third filter chamber A3 is further disposed adjacent to the first filter chamber a1 and the fourth filter chamber a4, and the seventh filter chamber a7 is further disposed adjacent to the fifth filter chamber a5 and the sixth filter chamber a 6; the distance between two filter cavities in the filter can be reduced, so that the eight filter cavities of the filter are tightly arranged, and the size of the filter is reduced. The third filter cavity A3 of the filter branch 12 intersects with the second filter cavity A2; the eighth filter cavity A8 of the filter branch 12 is arranged intersecting the seventh filter cavity a 7. For example, the third filtering cavity A3 of the filtering branch 12 intersects with the second filtering cavity a2, the third filtering cavity A3 and the second filtering cavity a2 have two intersection points, and the distance between the two intersection points can be the width of a window (not shown) between the third filtering cavity A3 and the second filtering cavity a2, and by the intersection arrangement of the filtering cavities, a partition wall is prevented from being required to be arranged between the two filtering cavities which are sequentially coupled in the conventional filter, and then a coupling window is arranged on the partition wall, so that materials are reduced, and the processing is convenient.

As shown in fig. 2, fig. 2 is a schematic diagram of a topology of the first filtering branch in fig. 1. The inductive cross-coupling is respectively formed between the first filter cavity a1 and the third filter cavity A3, between the third filter cavity A3 and the fifth filter cavity a5, and between the sixth filter cavity a6 and the eighth filter cavity A8 of the filter branch 12, so as to form three inductive cross-coupling zeros. Typically, the inductive cross-coupling element may be a metal coupling rib, i.e. a metal coupling rib is disposed between the first filter cavity a1 and the third filter cavity A3. Therefore, the filtering branch 12 realizes zero point suppression by setting three inductive cross-coupling zero points, so that the filtering branch 12 meets the design requirements and is convenient to debug. In addition, the inductive cross-coupling element of the embodiment can be a metal coupling rib, and the metal coupling rib is slightly changed by the external temperature, so that the temperature drift of the filter is avoided.

The cross-coupling zeros are also referred to as transmission zeros. 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.

Wherein the size of the first filter chamber a1, the size of the second filter chamber a2, the size of the third filter chamber A3, the size of the fourth filter chamber a4, the size of the fifth filter chamber a5, the size of the sixth filter chamber a6, the size of the seventh filter chamber a7 and the size of the eighth filter chamber A8 may be the same. Namely, the eight filter cavities 121 can be distributed equidistantly, so that the layout and debugging are facilitated, and the consistency of the filter is improved.

The filtering branch 12 of this embodiment is composed of eight filtering cavities coupled in sequence, and the eight filtering cavities of the filtering branch 12 further form three inductive cross-coupling zeros, which can realize zero suppression and facilitate debugging of indexes; all inductive cross coupling zero points are the same, inductive cross coupling elements are the same, the types of materials are reduced, the complexity of the filter is reduced, and the stability of the filter is improved. In addition, the inductive cross-coupling element of the embodiment can be a metal coupling rib, and the metal coupling rib is slightly changed by the external temperature, so that the temperature drift of the filter is avoided. In addition, eight filter chambers of the filter branch 12 are regularly arranged, so that a plurality of filters can be produced by the same die, the cost is reduced, and the stability is high.

Optionally, housing 11 is further provided with a first port (not shown) to which first filter chamber a1 is connected and a second port (not shown) to which eighth filter chamber A8 is connected. Wherein, the first port and the second port can be taps of the filter.

The filter branch 12 of this embodiment is a transmit filter branch and the bandwidth of the filter branch 12 is in the range 812Mhz-881 Mhz. Specifically, the coupling bandwidth between the first port and the first filter cavity A1 ranges from 77Mhz to 81 Mhz; the coupling bandwidth between the first filter cavity a1 and the second filter cavity a2 ranges from 52Mhz to 56 Mhz; the coupling bandwidth between the first filter cavity a1 and the third filter cavity A3 ranges from 29Mhz to 33 Mhz; the coupling bandwidth between the second filter cavity a2 and the third filter cavity A3 ranges from 33Mhz to 37 Mhz; the coupling bandwidth between the third filter cavity A3 and the fourth filter cavity a4 ranges from 33Mhz to 37 Mhz; the coupling bandwidth between the third filter cavity A3 and the fifth filter cavity a5 ranges from 18Mhz to 22 Mhz; the coupling bandwidth between the fourth filter cavity a4 and the fifth filter cavity a5 ranges from 32Mhz to 36 Mhz; the coupling bandwidth between the fifth filter cavity a5 and the sixth filter cavity a6 ranges from 38Mhz-42 Mhz; the coupling bandwidth between the sixth filter cavity a6 and the seventh filter cavity a7 ranges from 37Mhz-41 Mhz; the coupling bandwidth between the sixth filter cavity a6 and the eighth filter cavity A8 ranges from 21Mhz to 25 Mhz; the coupling bandwidth between the seventh filter cavity a7 and the eighth filter cavity A8 ranges from 56Mhz to 60 Mhz; the coupling bandwidth between the eighth filter cavity A8 and the second port ranges from 77Mhz to 81 Mhz. Therefore, the bandwidth of the filter of the embodiment is 812Mhz-881Mhz, which can meet the design requirement.

Therefore, the resonant frequencies of the first filter cavity a1 to the eighth filter cavity A8 are sequentially in the following ranges: 843Mhz-847Mhz, 864Mhz-868Mhz, 840Mhz-844Mhz, 862Mhz-866Mhz, 841Mhz-845Mhz, 840Mhz-844Mhz, 859Mhz-863Mhz, 843Mhz-847 Mhz. Therefore, the filtering branch 12 of the present embodiment can precisely control the bandwidth of the filtering branch 12 by setting three inductive cross-coupling zeros so that the bandwidth of the filtering branch 12 is within the range of 812Mhz-881Mhz, thereby meeting the design requirement of the filter.

As shown in fig. 3, fig. 3 is a diagram showing simulation results of the filter of fig. 1. Experimentally tested, the bandwidth of the filter of the present application was in the range of 812Mhz-881Mhz, as shown by the band curve 20 in FIG. 3. The three inductive cross-coupling zeros of the filter of the present application are respectively a zero B, a zero C, and a zero D, wherein the frequency of the zero B is 894.5MHz, and at this time, the bandwidth rejection of the filtering branch 12 is greater than 81dB, so that the out-of-band rejection performance of the filtering branch 12 can be improved. It should be noted that the parameters (e.g., frequency point and suppression) of two or more coupling zeros of the present application may be the same; in the simulation diagram, the coupling zeros of the same parameters are shown as the same coupling zeros.

The present application further provides a communication device, as shown in fig. 4, fig. 4 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).

The principle and the implementation of the present application are explained herein by applying specific examples, and the above description of the embodiments is only used to help understand the method and the core idea of the present application; meanwhile, for a person skilled in the art, according to the idea of the present application, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present application.

Claims (10)

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

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

and the eight filter cavities of the filter branch circuit form three inductive cross coupling zero points, and are divided into two rows arranged along the second direction.

2. The filter of claim 1,

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

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

3. The filter of claim 2,

the third filter cavity of the filter branch is further arranged adjacent to the first filter cavity and the fourth filter cavity, and the seventh filter cavity of the filter branch is further arranged adjacent to the fifth filter cavity and the sixth filter cavity;

a third filter cavity of the filter branch circuit is intersected with the second filter cavity;

and the eighth filtering cavity and the seventh filtering cavity of the filtering branch are arranged in an intersecting manner.

4. The filter of claim 3,

and the first filtering cavity and the third filtering cavity, the third filtering cavity and the fifth filtering cavity, and the sixth filtering cavity and the eighth filtering cavity of the filtering branch are respectively subjected to inductive cross coupling so as to form three inductive cross coupling zeros.

5. The filter according to claim 4, wherein the first side of the housing is further provided with a first port and a second port, the first filter cavity of the filter branch is connected with the first port, and the eighth filter cavity of the filter branch is connected with the second port.

6. A filter according to any of claims 1-5, characterized in that the bandwidth of the filter branches is in the range 812Mhz-881 Mhz.

7. 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 for filtering radio frequency signals, the filter comprising:

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

and the eight filter cavities of the filter branch circuit form three inductive cross coupling zero points, and are divided into two rows arranged along the second direction.

8. The communication device of claim 7,

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

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

the third filter cavity of the filter branch is further arranged adjacent to the first filter cavity and the fourth filter cavity, and the seventh filter cavity of the filter branch is further arranged adjacent to the fifth filter cavity and the sixth filter cavity;

a third filter cavity of the filter branch circuit is intersected with the second filter cavity;

and the eighth filtering cavity and the seventh filtering cavity of the filtering branch are arranged in an intersecting manner.

9. The communication device of claim 8,

and the first filtering cavity and the third filtering cavity, the third filtering cavity and the fifth filtering cavity, and the sixth filtering cavity and the eighth filtering cavity of the filtering branch are respectively subjected to inductive cross coupling so as to form three inductive cross coupling zeros.

10. A communication device according to any of claims 7-9, characterized in that the bandwidth of the filtering branch is in the range 812Mhz-881 Mhz.

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