WO2023098107A1

WO2023098107A1 - Resonator, dielectric filter, and communication device

Info

Publication number: WO2023098107A1
Application number: PCT/CN2022/107762
Authority: WO
Inventors: 李慧婷; 王华红
Original assignee: 华为技术有限公司
Priority date: 2021-11-30
Filing date: 2022-07-26
Publication date: 2023-06-08
Also published as: CN116207470A

Abstract

The present application discloses a resonator, a dielectric filter, and a communication device. The resonator comprises a dielectric body and an electrode, wherein a through hole is formed in the dielectric body; the through hole penetrates through the top surface and the bottom surface of the dielectric body; the side surfaces of the dielectric body are between the top surface and the bottom surface; the bottom surface and the side surfaces of the dielectric body are covered with a metal layer; the electrode is provided on a first side surface of the dielectric body; the electrode is insulated from the metal layer on the first side surface; a first metal area is formed on the top surface, wherein the first metal area is connected to the through hole in the top surface; a second metal area is also formed on the top surface; the second metal area comprises at least one metal strip; a first end of the second metal area is connected to the electrode, and a second end of the second metal area is connected to the first metal area; and an insulating gap is further present between the second metal area and the first metal area. The resonator relates to both inductive coupling and capacitive coupling. The resonant frequency is adjusted by adjusting a combination relationship of inductive coupling and capacitive coupling, and the adjustment is flexible.

Description

A kind of resonator, dielectric filter and communication equipment

This application claims the priority of the Chinese patent application with the application number 202111453150.4 and the application name "A Resonator, Dielectric Filter and Communication Equipment" submitted to the State Intellectual Property Office of China on November 30, 2021, the entire content of which is passed References are incorporated in this application.

technical field

The present application relates to the technical field of electronic devices, in particular to a resonator, a dielectric filter and communication equipment.

Background technique

In a wireless local area network (WLAN, Wireless Local Area Network), both data reception and transmission need to pass through the antenna, and in order to receive and transmit data with high quality, the antenna is connected with a filter, and the filter is used to filter the received and transmitted data .

At present, the frequency band division of wireless communication is more and more high-frequency and broadband-oriented. For example, the current frequency band division of WIFI includes 2.4G, 5G and 6E. GHz, the frequency band of 6E is 5.925GHz-7.125GHz. Compared with the frequency band of WIFI5G, WIFI6E has a higher frequency band and a wider bandwidth of 1.2GHz. The wider the bandwidth, the higher the requirements for the filter. Moreover, base stations for wireless communication are becoming more and more miniaturized, requiring filters to be more and more miniaturized. Since the dielectric filter can be miniaturized compared with other types of filters, the dielectric filter is widely used in wireless communication.

The so-called dielectric filter (Dielectric Filter) is a filter using a dielectric resonator, and the dielectric resonator (Dielectric Resonator) is formed by repeated total reflection of electromagnetic waves inside the medium. The resonant cavity in the dielectric resonator is a component that can store electromagnetic energy. The electric field energy and magnetic field can be converted according to a certain time, which is called the oscillation process, and the frequency of the oscillation is called the resonance frequency. Dielectric filters generally include multiple resonators, and multiple resonators are cascaded together. The first resonator is called the first cavity, and the tail resonator is called the tail cavity. Both the cavity and the tail cavity are provided with input and output coupling structures. In the case of the same return loss, the bandwidth of the dielectric filter is determined by the coupling strength of the input and output, the stronger the coupling, the larger the bandwidth. Therefore, the input and output coupling structure of the dielectric filter directly affects the bandwidth. For a bandpass filter, its bandwidth is the upper sideband minus the lower sideband of the passband.

However, in the current dielectric filter, the bandwidth corresponding to the input-output coupling structure of the resonator is relatively narrow, which cannot meet the current requirement of wide bandwidth.

Contents of the invention

In order to solve the above technical problems, the present application provides a resonator, a dielectric filter and a communication device, which have a relatively high bandwidth and can meet the requirement of a relatively wide bandwidth.

The resonator provided by this application includes a dielectric body and electrodes. The dielectric body is provided with a through hole, the through hole runs through the top surface and the bottom surface of the dielectric body, and the side surface of the dielectric body is between the top surface and the bottom surface. The bottom surface and the side surface of the dielectric body are covered with The metal layer, the electrode is arranged on the first side of the dielectric body, the electrode is insulated from the metal layer on the first side, and on the top surface, there is a first metal region, wherein the first metal region is connected to the top surface On the top surface, there is also a second metal area, the second metal area includes at least a section of metal strip, the first end of the second metal area is connected to the electrode, and the second end of the second metal area is connected to the first A metal area, an insulating gap is formed between the second metal area and the first metal area.

Since the resonator provided in this application includes both capacitive coupling and inductive coupling; the total coupling strength is the difference between the inductive coupling strength and the capacitive coupling strength. If the inductive coupling strength is greater than the capacitive coupling strength, the overall coupling polarity appears inductive. If the capacitive coupling strength is greater than the inductive coupling strength, the overall coupling polarity is capacitive. Both inductive coupling and capacitive coupling will affect the resonant frequency of the resonator. Therefore, the resonant frequency of the resonator can be adjusted by adjusting the combination relationship between inductive coupling and capacitive coupling. In the case of a certain total coupling strength, There are many combinations of capacitive coupling and inductive coupling, and the adjustment is flexible. This can ensure that the required resonant frequency is realized in the resonator with a limited volume, so that the filter including the resonator can meet the requirements of the application scene for the passband and bandwidth. For example, the length of the coupling slit of capacitive coupling can be reduced and the width can be increased, so that the actual processing can be used to improve the tolerance of tolerance, etc.

The present application does not limit the specific implementation form of the second metal region, and the number of metal strips included in the second metal region may be one or more. The following examples introduce several specific implementation manners.

In the first type, the second metal region only includes a section of metal strip, the first end of a section of metal strip is connected to the electrode, the second end of a section of metal strip is connected to the first metal region, and a metal strip is formed between the second metal region and the first metal region. There are insulation gaps.

In the second type, the second metal region includes at least the following two sections of metal strips: the first section of metal strip and the second section of metal strip; the connection methods of the two sections of metal strips are similar, that is, the first end of the first section of metal strip is connected to the electrode, The second end of the first metal strip is connected to the first metal area, and an insulating gap is formed between the first metal strip and the first metal area; the first end of the second metal strip is connected to the electrode, and the second metal strip is connected to the electrode. The second end of the strip is connected to the first metal region, and an insulating gap is formed between the second segment of the metal strip and the first metal region. When the second metal region of the resonator includes multiple segments of metal strips, different capacitive coupling strengths and inductive coupling strengths can be realized by adjusting the length and width of each metal strip, thereby making the adjustment more flexible and diverse.

In the third type, the second metal area includes at least the following two sections of metal strips: the first section of metal strips and the second section of metal strips; the connection methods of the two sections of metal strips are different, that is, the first end of the first section of metal strips is connected An electrode, the second end of the first metal strip is connected to the first metal region, and an insulating gap is formed between the first metal strip and the first metal region; the first end of the second metal strip is connected to the electrode, and the second The second end of the metal strip is insulated from the first metal region, and an insulating gap is formed between the second segment of the metal strip and the first metal region. When the second metal region of the resonator includes multiple sections of metal strips, the connection methods of different sections of metal strips are different, so that the length and width of each metal strip can be adjusted more flexibly to achieve different capacitive coupling strength and inductive coupling. strength.

The second metal region of the resonator provided in the present application may include multiple segments of metal strips, or a segment of metal strips. The second metal region will be introduced as a whole below, that is, the second metal region may include multiple ends, different ends Different positions can be connected, and the specific shape of the second metal region is not specifically limited. The second metal region also includes at least one third end, and at least one third end has a coupling gap with the first metal region, that is, the third end is not connected to the first metal region. One metal region, but there is an insulating gap with the first metal region, thereby forming a capacitive coupling.

In another possible implementation manner, the second metal region further includes at least one fourth terminal, at least one fourth terminal is electrically connected to the first metal region, that is, the fourth terminal is not insulated from the first metal region, but is electrically connected, Thus forming an inductive coupling.

The application does not specifically limit the shape of the metal strip, for example, it can be straight, it can be interdigitated, it can also be other shapes with bending, etc. Generally, for the convenience of adjusting the coupling strength, at least one metal strip can be set to be electrically connected to the first metal region after being bent for a preset number of times; the preset number of times is greater than or equal to 1.

The present application does not limit the length and width of the metal strip. For example, it can be arranged uniformly or unevenly, and can be of equal or unequal width. For the convenience of processing and manufacturing in the process, at least one section of the metal strip can be set to be equal in width in the direction of extension. .

The resonator provided by the present application includes both inductive coupling and capacitive coupling, the insulating gap is used to generate capacitive coupling, the second end of the second metal region is connected to the first metal region to generate inductive coupling, and the capacitive coupling is greater than the inductive coupling , the resonator exhibits capacitive coupling; the capacitive coupling is smaller than the inductive coupling, and the resonator exhibits inductive coupling.

Introduce the influence of the length and width of the coupling gap on the inductive coupling strength and capacitive coupling strength. Since both types of coupling exist, the total coupling polarity presented by the resonator is inductive or capacitive; when the total coupling polarity presented by the resonator When the properties are different, the influence of the coupling gap on the coupling strength is also different.

The first type - the input and output coupling of the resonator is capacitive coupling:

The coupling strength of the input-output coupling structure is proportional to the length of the coupling slit, that is, the longer the coupling slit, the greater the total coupling strength; the coupling strength of the input-output coupling structure is inversely proportional to the width of the coupling slit, that is, the wider the coupling slit Narrower, the greater the total coupling strength; the total coupling strength is the capacitive coupling strength.

The second type - the input and output coupling of the resonator is inductive coupling:

The coupling strength of the input-output coupling structure is inversely proportional to the length of the coupling gap, that is, the longer the coupling gap is, the smaller the total coupling strength is; the coupling strength of the input-output coupling structure is proportional to the width of the coupling gap, that is, the wider the coupling gap is Narrow, the smaller the total coupling strength; the total coupling strength is the inductive coupling strength.

Based on the resonator provided in the above embodiments, the present application also provides a dielectric filter, including two or more resonators described above: a first resonator and a second resonator, and at least one third resonator, the first resonator The three resonators do not have a second metal region; the input-output coupling structure of the first resonator is used for the input signal; the third resonator is used for transmitting the input signal to the second resonator; the input-output coupling of the second resonator Structure for output signals.

Since the input and output coupling structures in the first resonator and the second resonator included in the filter provided by the present application include inductive coupling and capacitive coupling, the frequency selection range of the filter can be flexibly adjusted to facilitate obtaining a wider bandwidth The corresponding frequency band, for example, the bandwidth of the bandpass filter is the upper side frequency minus the lower side frequency, and the difference between capacitive coupling and inductive coupling can obtain a lot of upper side frequency and lower side frequency, therefore, more bandwidth can be obtained, which can satisfy Scenarios with wide bandwidth requirements, such as meeting the communication requirements of 6E with a bandwidth of 1.2 GHz.

The present application also provides a communication device, including: an antenna and the above-mentioned dielectric filter; the dielectric filter is used to perform band-pass filtering on the received signal and then transmit it to the antenna, so that the antenna can wirelessly transmit the filtered signal ; The dielectric filter is also used for band-pass filtering the signal received by the antenna wirelessly.

With the continuous development of wireless communication technology, the bandwidth requirement is getting wider and wider, but the size of each device used in wireless communication is getting smaller and smaller. Therefore, it is necessary to realize the miniaturization of the size of the dielectric filter. All processing steps require the use of filters. The dielectric filter in the communication device provided by the embodiment of the present application can realize a wide bandwidth while ensuring a small size, and is convenient for actual processing. In addition, the embodiment of the present application does not limit whether the antenna and the dielectric filter are integrated together, they may be integrated together, or may be independent components.

This application has at least the following advantages:

The resonator includes a dielectric body and electrodes; the top surface of the dielectric body is provided with a first metal area and a second metal area, the second metal area includes at least a section of metal strip, and the first end of the second metal area is electrically connected to the electrode; The second ends of the two metal regions are electrically connected to the first metal region to form an inductive coupling, and there is an insulating gap between the second metal region and the first metal region to form a capacitive coupling. Both capacitive coupling and inductive coupling are formed between the second metal region and the first metal region; the total coupling strength is the difference between the inductive coupling strength and the capacitive coupling strength. If the inductive coupling strength is greater than the capacitive coupling strength, the overall coupling polarity appears inductive. If the capacitive coupling strength is greater than the inductive coupling strength, the overall coupling polarity is capacitive. Both inductive coupling and capacitive coupling will affect the resonant frequency of the resonator. Therefore, the resonant frequency of the resonator can be adjusted by adjusting the combination relationship between inductive coupling and capacitive coupling. In the case of a certain total coupling strength, There are many combinations of capacitive coupling and inductive coupling, and the adjustment is flexible. This can ensure that the required resonant frequency is realized in the resonator with a limited volume, so that the filter including the resonator can meet the requirements of the application scene for the passband and bandwidth. For example, the length of the coupling slit of capacitive coupling can be reduced and the width can be increased, so that the actual processing can be used to improve the tolerance of tolerance, etc.

Description of drawings

FIG. 1 is a schematic diagram of a dielectric filter provided in an embodiment of the present application;

FIG. 2 is a schematic diagram of an application scenario of a dielectric filter provided in an embodiment of the present application;

FIG. 3 is a schematic diagram of bandwidths corresponding to various communications;

Figure 4A is an equivalent circuit diagram when the resonator only includes capacitive coupling;

Figure 4B is a schematic diagram of a capacitively coupled resonator corresponding to Figure 4A;

FIG. 4C is an equivalent circuit diagram in which the resonator only includes inductive coupling;

FIG. 4D is a schematic diagram of a resonator corresponding to FIG. 4C including inductive coupling;

FIG. 5 is a schematic diagram of a resonator provided in an embodiment of the present application;

FIG. 6 is a schematic diagram of a specific resonator provided in an embodiment of the present application;

FIG. 7 is a schematic diagram of another resonator provided in the embodiment of the present application;

Fig. 8 is an equivalent circuit diagram corresponding to Fig. 6 and Fig. 7 provided by the embodiment of the present application;

FIG. 9 is a top view corresponding to FIG. 8 provided by the embodiment of the present application;

FIG. 10 is a top view of another resonator according to the embodiment of the present application;

Fig. 11 is an equivalent circuit diagram corresponding to Fig. 6 to Fig. 9 provided by the embodiment of the present application;

FIG. 12 is a schematic diagram of a fourth-order filter provided in an embodiment of the present application;

FIG. 13 is a schematic diagram of a communication device provided by an embodiment of the present application.

Detailed ways

The technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application.

Words such as "first" and "second" in the following descriptions are used for description purposes only, and should not be understood as indicating or implying relative importance or implicitly indicating the quantity of indicated technical features. Thus, a feature defined as "first", "second", etc. may expressly or implicitly include one or more of that feature. In the description of the present application, unless otherwise specified, "plurality" means two or more.

In this application, unless otherwise specified and limited, the term "connection" should be understood in a broad sense, for example, "connection" can be a fixed connection, a detachable connection, or an integral body; it can be a direct connection, or It can be connected indirectly through an intermediary. In addition, the term "coupled" may be an electrical connection for signal transmission. "Coupling" can be a direct electrical connection, or an indirect electrical connection through an intermediary.

In order to enable those skilled in the art to better understand the technical solutions provided by the embodiments of the present application, the application scenarios of the technical solutions will be introduced below with reference to the accompanying drawings.

The embodiment of the present application relates to a resonator. In order to enable those skilled in the art to better understand the application scenarios of the resonator provided in the embodiment of the present application, the application of the resonator in a dielectric filter is taken as an example for introduction. The application does not limit the number of resonators included in the dielectric filter, which can be set according to specific needs. The more the order of the dielectric filter, the more the number of resonators included. For example, the dielectric filter can include four resonators. , corresponding to a fourth-order dielectric filter, may also include six resonators, corresponding to a sixth-order dielectric filter. In addition, the resonator can also be applied to other devices, as long as the device has a resonant function, such as an oscillator, only one resonator can be included in the oscillator, that is, it can function as a crystal oscillator, as a single resonator. The resonator provided in the embodiment of the present application can be used in a frequency selection network in signal processing, that is, to select a signal in a preset frequency range to pass or not to pass. The application does not limit the specific type of the dielectric filter, for example, it may be a band-pass filter, a band-stop filter, a high-pass filter, or a low-pass filter. Among them, the resonator can also be applied in the duplexer, and the duplexer can be regarded as a special form of the filter.

Referring to FIG. 1 , the figure is a schematic diagram of a dielectric filter provided by an embodiment of the present application.

In FIG. 1 , the dielectric filter includes four cascaded resonators as an example for illustration.

The dielectric filter includes a first resonator S, a second resonator W and two third resonators A and B. Wherein, the first resonator S is used as the first resonator, that is, the first cavity, and the fourth resonator W is used as the tail resonator, that is, the tail cavity.

In this application, the dielectric body of the resonator is introduced as a cuboid or a cube as an example, and it may also be of other types. The top surface of the resonator is an open surface, and the bottom surface is a short-circuit surface, which is used to connect the ground of the circuit board.

The first resonator S and the second resonator W serve as an input terminal and an output terminal of signals respectively. For example, the signal enters from the first resonator S, the first resonator S transmits the signal to the third resonator A, the third resonator A transmits the signal to the third resonator B, and the third resonator B transmits the signal to the second resonator The resonator W, the second resonator W transmits the signal. Wherein, signal transmission is performed between two adjacent resonators through an electromagnetic field.

Since the first resonator S needs to receive signals from the outside of the dielectric filter, the top surface of the first resonator S includes an input-output coupling structure for input signals; in addition, because the second resonator W needs to transmit signals to In addition to the dielectric filter, therefore, the top surface of the second resonator W also includes an input-output coupling structure for outputting signals.

Depending on the design of the input-output coupling structure, the performance of the input-output coupling of the resonator is different. The resonator can be inductive coupling or capacitive coupling.

The following uses the application of a dielectric filter in a WLAN as an example for introduction. For the convenience of introduction, the dielectric filter is referred to as a filter for short below.

Referring to FIG. 2 , this figure is a schematic diagram of an application scenario of a dielectric filter provided by an embodiment of the present application.

The filter FIL is bidirectionally connected to the antenna ANT, that is, the filter FIL can both send signals to the antenna ANT and receive signals from the antenna ANT. The filter FIL implements filtering of the signal.

Under the same return loss condition, the achievable bandwidth of the filter is directly determined by the input-output coupling strength, see formula (1) for the input-output coupling strength. The input-output coupling strength is characterized by the external Q value Qe, the smaller the Qe, the stronger the coupling and the larger the bandwidth.

Qe＝f0/(BW*ms1*ms1) (1)

Among them, f0 is the center frequency, BW is the bandwidth, BW is the passband upper side frequency of the filter minus the passband lower side frequency; ms1 is the normalized coupling coefficient.

The current division of communication frequency bands is shown in Figure 3. The relative bandwidth of WIFI2.4G is 2.95%, the relative bandwidth of 5G is 17.6%, and the relative bandwidth of 6E is 18.4%. The bandwidth of 6E is 1.2GHz. It is difficult to meet the requirements of miniaturization and achieve the required bandwidth by using traditional capacitively coupled filters.

If only capacitive coupling is used to realize the bandwidth of 6E, the coupling gap forming capacitive coupling needs to be elongated. The longer the coupling gap, the greater the coupling strength, but elongating the coupling gap will cause the actual volume to become larger; The greater the narrow coupling strength, but the narrower the coupling gap, the poorer the tolerance for tolerances. In actual processing, it leads to processing difficulties and cannot guarantee the input and output coupling strength.

Referring to FIG. 4A , it is an equivalent circuit diagram when the resonator only includes capacitive coupling.

In this embodiment, the resonator is LC parallel resonance as an example, that is, the first inductance L1 and the first capacitor C1 are connected in parallel. It should be understood that L1 and C1 are the inductance and capacitance equivalent to the structure of the resonator itself. The capacitive coupling equivalent to the input-output coupling structure of the resonator is the second capacitor C2, that is, L1 and C1 are connected in parallel and then connected in series with C2.

Referring to FIG. 4B , it is a schematic diagram of a capacitively coupled resonator corresponding to FIG. 4A .

Taking the cuboid as an example, the resonator includes six faces, namely a top face, a bottom face, and four side faces.

The through hole K runs through the top surface and the bottom surface, the inner wall of the through hole K is covered by the metal layer, and the three sides and the bottom surface except the side where the electrode D is located are covered with the metal layer.

An electrode D is provided on the surface 3 , and an insulating gap G is provided between the electrode D and the metal layer of the surface 3 . The electrode D is used for electrical connection with the outside world for signal transmission. A first metal area is provided on the top surface to be electrically connected to the through hole K, and an insulating gap is generally provided at the boundary between the first metal area and the top surface. Wherein, no matter the resonator is a cube or a cuboid, the side where the electrode D is located is perpendicular to the top surface, which is convenient for processing and manufacturing.

The capacitive coupling of the resonator means that there is an insulating gap N between the metal region 11 on the top surface and the first metal region M, that is, the insulating gap N forms a capacitive coupling, that is, C2 in FIG. 4A is the capacitive coupling, etc. effective capacitance.

The above description is about the resonator including only the capacitive coupling, and the resonator including only the inductive coupling will be introduced below with reference to the accompanying drawings.

Referring to FIG. 4C , it is a schematic diagram of a resonator including inductive coupling.

In this embodiment, the resonator is LC parallel resonance as an example, that is, the first inductance L1 and the first capacitor C1 are connected in parallel. It should be understood that L1 and C1 are the inductance and capacitance equivalent to the structure of the resonator itself. It can be seen from FIG. 4C that the inductance L2 is an inductance equivalent to inductive coupling.

Referring to FIG. 4D , this figure is an equivalent circuit diagram of the resonator corresponding to FIG. 4C including only inductive coupling.

The parts in FIG. 4C that are the same as those in FIG. 4B will not be repeated here. Only the parts in FIG. 4C that are different from those in FIG. The electrical connection forms an inductive coupling.

For resonators that only include inductive coupling, there are the following disadvantages: the coupling strength is related to the line width and line length of the metal strip X, the narrower and longer the line length, the weaker the coupling, and the wider and shorter the line length, the stronger the coupling, at the top In the case of a small surface area, it is difficult to reduce the coupling strength. In addition, once the metal strip X is processed, the length cannot be adjusted basically, and the width is also difficult to adjust, that is, it is difficult to adjust the coupling strength.

To sum up, neither purely capacitively coupled resonators nor purely inductively coupled resonators can meet the bandwidth requirements of current communications.

Resonator Embodiment

Based on the technical problem that the current WLAN communication requires wider and wider bandwidths, and the volume of the filter is required to be as small as possible in practical applications, the embodiment of the present application provides a resonator. The input and output coupling structure of the resonator includes both capacitive coupling and , including inductive coupling. Since the characteristics of capacitive coupling and inductive coupling determine that the phase difference between capacitive coupling and inductive coupling is 180 degrees, the overall coupling strength is the difference between the capacitive coupling strength and the inductive coupling strength, so it is convenient to adjust the final coupling of the resonator Intensity, thereby achieving a wider bandwidth.

The resonator provided by the embodiment of the present application will be described in detail below with reference to the accompanying drawings.

Referring to FIG. 5 , this figure is a schematic diagram of a resonator provided by an embodiment of the present application.

Taking the resonator as a cuboid as an example, it includes six faces, namely face 1-face 6, wherein face 1 is the top face, face 2 is the bottom face, the top face and the bottom face are arranged oppositely, and face 3-face 6 are four sides. There is a through hole between the surface 1 and the surface 2, the inner wall of the through hole and the surface 2-surface 6 are covered by the metal layer, the electrode is provided on the surface 3, and the insulating gap is provided between the electrode and the metal layer of the surface 3. The electrodes are used for electrical connection with the outside world for signal transmission. A first metal area is provided on the surface 1 to be electrically connected to the through hole 1 , and an insulating gap is generally provided at the boundary between the first metal area and the surface 1 . Wherein, no matter the resonator is a cube or a cuboid, the side where the electrodes are located is perpendicular to the top surface, which is convenient for processing and manufacturing.

Referring to FIG. 6 , this figure is a perspective schematic diagram of a specific resonator provided in an embodiment of the present application.

The following describes the resonator provided in this embodiment with reference to FIG. 5 and FIG. 6, including: a dielectric body (take a cuboid as an example), a through hole K, an electrode D, and an input-output coupling structure X;

The two surfaces of the dielectric body penetrated by the through hole K are the top surface 1 and the bottom surface 2 respectively, the electrode D is arranged on the side surface 3 of the dielectric body, and the inner wall of the through hole K and the side surface of the dielectric body are covered with a metal layer, such as side 4-side 6. The bottom surface 2 is also covered with a metal layer; an insulating gap G is provided between the electrode D and the metal layer on the side;

The top surface 1 is provided with a first metal region M connected to the through hole K, and at least a second metal region X is provided on the top surface 1 other than the first metal region M, that is, the input-output coupling structure of the resonator;

The second metal region X includes at least one section of metal strip, the first end 11 of the second metal region X is electrically connected to the electrode D; the second end 22 of the second metal region X is electrically connected to the first metal region M to form an inductive coupling, and the second metal There are insulating coupling gaps between the region X and the first metal region M to form capacitive coupling, such as the coupling gaps N1 and N2 in FIG. 6 . The coupling gap refers to the gap between the boundary of the second metal region X and the first metal region M.

The embodiment of the present application does not limit the number of segments of the metal strip, nor does it limit the specific shape of the metal strip, for example, it may be a broken line, or a curved line, etc., or a combination of the two lines. In addition, it is not limited whether the width of the metal strip is uniform, for example, it may be a metal strip with a uniform width, or a metal strip with a variable width, that is, some positions of the metal strip have a larger width, and some positions have a smaller width.

For details, please refer to FIG. 7 , which is a top view corresponding to FIG. 6 provided by the embodiment of the present application.

The structure of the input-output coupling structure can be seen more clearly from FIG. 7. The capacitive coupling gap formed between the metal strip X and the first metal region M includes N1 and N2, that is, the capacitive coupling is formed. The embodiment of the present application does not The shape of the coupling gap that defines the capacitive coupling can be, for example, straight, interdigitated, or other shapes with bends. The embodiment of the present application does not limit the number of times of bending, for example, at least one metal strip is electrically connected to the first metal region after being bent for a predetermined number of times; In addition, due to the direct connection between the metal strip X and the first metal region M, that is, the first end 11 of the metal strip X is connected to the electrode, and the second end 22 of the metal strip X is connected to the first metal region M, that is, an inductive coupling is formed. The input-output coupling structure provided by the embodiment of the present application includes both inductive coupling and capacitive coupling, and the total coupling strength is the difference between the inductive coupling strength and the capacitive coupling strength. In order to facilitate the actual processing and manufacturing, the uniform width of the metal strip X is introduced as an example in FIG. 7 .

In FIG. 7 , the electrode is extended to the top surface where the first metal region is located to form a metal strip as an example. The metal strips are all in the same extension direction. For example, after extending to the right in FIG. 7 , they are directly electrically connected to the first metal region M. . The embodiment of the present application does not limit the number of bending times of the metal strip, which can be selected according to actual needs.

In the embodiment of the present application, the cross section of the through hole K is circular as an example for introduction. It should be understood that the cross section of the through hole K may also be in other shapes, for example, rectangular, square or elliptical.

It can be seen from Figure 7 that the metal strip X not only has a direct connection with the first metal region M to form an inductive coupling, but also has a coupling gap between the first metal region M to form a capacitive coupling. Therefore, the input and output of the resonator Coupling is affected by both capacitive coupling strength and inductive coupling strength. Since the polarity of capacitive coupling and inductive coupling is opposite, when they exist at the same time, the total coupling strength is equal to the difference between capacitive coupling strength and inductive coupling strength. For example, if the inductive coupling strength is 2000MHz and the capacitive coupling strength is 500MHz, then the total coupling strength is 1500MHz for inductive coupling. Conversely, if the capacitive coupling strength is 2000MHz and the inductive coupling strength is 500MHz, then the total coupling strength is capacitive coupling 1500MHz. Therefore, by adjusting the inductive coupling strength and the capacitive coupling strength, the total coupling strength is the difference between the two, and a variety of total coupling strengths can be flexibly obtained, thereby adapting to the requirements of different application scenarios for passband and bandwidth. Under the condition that the total coupling strength is the same, a variety of values can be selected for the capacitive coupling strength and the inductive coupling strength. When the total coupling strength remains unchanged, the capacitive coupling strength and the inductive coupling strength can be weakened at the same time by design, so that the length of the coupling gap in the capacitive coupling part is reduced and the width is increased, thereby improving the tolerance for tolerance in actual processing .

When the total coupling is inductive coupling, the total coupling strength is equal to the inductive coupling strength minus the capacitive coupling strength, then the inductive coupling strength is the sum of the total coupling strength and the capacitive coupling strength, and the inductive coupling strength is greater than the total coupling strength. The inductive coupling strength is determined by the line length and line width of the metal strip directly connected to the first metal region. The longer and narrower the line of the metal strip, the weaker the coupling, that is, the smaller the coupling strength. The resonator provided in this embodiment includes inductive coupling and capacitive coupling. Compared with a resonator that only includes inductive coupling, the length of the metal strip of the present application can be reduced and the width can be increased, so the occupation of the top surface (opening) can be reduced. The area of the road surface is conducive to the miniaturization of the filter. At the same time, the increase in the width of the metal strip can also increase the tolerance for tolerance in actual processing.

Both capacitive coupling and inductive coupling have an impact on the resonant frequency of the resonator, wherein the capacitive coupling reduces the resonant frequency of the resonator, and the inductive coupling increases the resonant frequency of the resonator. When the two exist at the same time, the influence on the resonant frequency of the resonator is offset, so that the offset of the input-output coupling structure to the resonant frequency can be reduced, which is beneficial to the miniaturization design, processing and debugging of the filter. For example, if a resonator includes only capacitive coupling, it will shift the resonant frequency of the resonator to a lower frequency, and the stronger the coupling, the greater the resonant frequency shift. If the resonator only includes inductive coupling, the resonant frequency of the resonator will be shifted to high frequency, and the stronger the coupling strength, the greater the resonant frequency shift.

Traditionally, in order to adjust the offset of the resonant frequency of the resonator, it is adjusted by adjusting other parameters that affect the resonant frequency, but other parameters have an adjustment range and cannot be adjusted indefinitely, otherwise the size of the resonator will be large, and the The actual machining tolerances have adverse effects. For example, for a resonator including only capacitive coupling, the resonant frequency of the resonator can be achieved by adjusting the size of the first metal region connected to the through hole, and also by adjusting the length of the through hole. But if the resonant frequency shift of the resonator is too large, it will exceed the adjustable range of the first metal area or the length of the through hole. In the actual filter, the length of the through holes of the multiple resonators included in the filter may be Inconsistency, difficult processing, such as the mold cannot be formed, the corners that need to be covered with metal cannot be covered, etc. For the resonator including only inductive coupling, the metal strip is directly connected to the first metal region. Once processed, the length of the metal strip is difficult to adjust, and the width of the metal strip is also limited by the processing technology.

However, the technical solution provided by the present application can utilize the effect of inductive coupling and capacitive coupling on the offset offset of the resonance frequency, which is beneficial to the processing and manufacturing of the resonator.

The length and width of the insulation gap of the capacitive coupling part of the input-output coupling structure can be adjusted by grinding the metal layer. The adjustment method is simple and convenient, and the strength of the coupling structure can be adjusted during the product design and debugging stages. In addition, the technical solution provided by the embodiment of the present application can flexibly adjust the inductive coupling strength and capacitive coupling strength, so it is more convenient for the manufacture of each resonator. In addition to the first cavity and the tail cavity, the filter also includes For the other intermediate resonators, during manufacture, the shapes and sizes of all the resonators included in the filter are uniform, and the lengths of the through holes are also uniform, which is convenient for processing and production.

The material of the metal strip X may be the same as that of the electrode D, specifically, at least one section of the metal strip X may be formed by extending from the electrode D to the top surface.

The input-output coupling structure of the resonator has both capacitive coupling and inductive coupling. The inductive coupling is generated by the metal strip X connecting the electrode to the first metal region, and the capacitive coupling is generated by the insulating gap between the metal strip X and the first metal region. The width and total length of the magnetically coupled conductor part can adjust the inductive coupling strength; controlling the length and width of the insulation gap can adjust the capacitive coupling strength.

In the embodiment of the present application, the number of ends of the metal strip is not limited. In FIG. 6 , the metal strip includes both ends as an example. That is, the first end 11 of the metal strip is connected to the electrode D, and the second end 22 of the metal strip is connected to the first Metal Zone M. In addition, the metal strip may also include three or four ends, that is, in addition to the first end and the second end, it may also include a third end, or may also include a fourth end, or may include both the third end and the fourth end. , will be introduced in detail below in conjunction with the accompanying drawings.

The metal strips included in the input-output coupling structure shown in Figure 6 and Figure 7 extend in one direction, that is, include a branch, and another input-output coupling structure is introduced below in conjunction with Figure 8 and Figure 9, that is, the metal strip includes more The branches include, for example, two branches, and the two branches respectively extend in two different directions.

Referring to FIG. 8 , this figure is a schematic diagram of another resonator provided by an embodiment of the present application.

The first end 11 of the metal strip of the input-output coupling structure in FIG. 8 is connected to the electrode D, the second end 22 of the metal strip is connected to the first metal region M, and the third end 33 of the metal strip is not connected to the first metal region M. , that is, the coupling gap formed between the third end 33 of the metal strip and the first metal region M is capacitive coupling N1, and another coupling gap formed between a section of the metal strip and the first metal region M is capacitive coupling N2 . The second end 22 of the metal strip extends to the left and is directly electrically connected to the first metal region M, and the third end 33 of the metal strip extends to the right and is not connected to the first metal region M, that is, it is open.

In addition, the metal strip in FIG. 8 can be regarded as extending to the top surface of the electrode D and including branches in two different directions, one of which is not connected to the first metal region M, and has a coupling gap with the first metal region M; The branches are connected to the first metal region M, and there is a coupling gap between a section of the metal strip and the first metal region M, that is, the branches in the other direction form both inductive coupling and capacitive coupling.

In this embodiment, the number of bending times and the specific length and width of the metal strip are not specifically limited, as shown in FIG. 9 , which is a top view corresponding to FIG. 8 provided in the embodiment of the present application. In FIG. 9, the width of the metal strip is equal in the extending direction as an example to facilitate the realization of the process in actual production and manufacturing.

It can be seen more clearly from FIG. 9 that the input-output structure provided by the embodiment of the present application includes coupling gaps N1 and N2, and both N1 and N2 form a capacitive coupling; in addition, the second end 22 of the metal strip is connected to the first The metal regions M are directly electrically connected to form an inductive coupling.

In Fig. 8 and Fig. 9, only the metal strip includes three ends, the first end, the second end and the third end. The above is only an example. In addition, if the area of the top surface allows, more metal strips can be added, that is, more branches. For example, the metal strip includes four ends, except the first end and the second end in Fig. 8 In addition to the third terminal, a fourth terminal is also included, and the fourth terminal is directly connected to the first metal region M. A detailed introduction will be made below in conjunction with the accompanying drawings.

Referring to FIG. 10 , this figure is a top view of another resonator provided by the embodiment of the present application.

In addition to the second end 22 of the metal strip of the input-output coupling structure in FIG. 10 being directly electrically connected to the first metal region M, the fourth end 44 of the metal strip is also directly connected to the first metal region M, which is the input-output coupling of the resonator. There are two direct connections between the metal strip and the first metal region M in the structure, both of which form inductive coupling. N1 and N2 in FIG. 10 are coupling gaps, forming capacitive coupling, that is, the input-output coupling structure includes both inductive coupling and capacitive coupling.

In addition, the metal strip can also include the first end, the second end, the third end and the fourth end, and besides this, it can also include a larger number of branches, for example, four branches or five branches, etc., here No more specific examples will be given.

In order for those skilled in the art to better understand the resonator provided by the embodiment of the present application that includes both capacitive coupling and inductive coupling, please refer to FIG. 11 , which is an equivalent circuit diagram corresponding to FIG. 6 to FIG. 9 .

L1 and C1 in FIG. 11 are similar to those in FIG. 4 , and will not be repeated here. They are the equivalent inductance and capacitance of the structure of the resonator, and the two are connected in parallel. The input-output coupling structure involved in this application is equivalent to the inductor L2 and capacitor C2 based on the structure of the resonator, and L2 and C2 are also connected in parallel, that is, L1 and C2 are connected in series and parallel after L2 and C2 are connected in parallel.

For example, the top surface of the resonator is an open-circuit surface, and the bottom surface of the resonator is a short-circuit surface, which may specifically be a quarter-wavelength resonator. In addition, the resonator may also be other types of resonators, which are not specifically limited in this embodiment of the present application.

The following describes how to adjust the capacitive coupling strength of the input-output coupling structure in the resonator, and how to adjust the inductive coupling strength. The length and width of the coupling gap will affect the inductive coupling strength and the capacitive coupling strength. In addition, the length and width of the metal strip will also affect the inductive coupling strength and the capacitive coupling strength.

First, the influence of the length and width of the coupling gap on the inductive coupling strength and capacitive coupling strength is introduced. Since both types of coupling exist, the total coupling polarity presented by the resonator is inductive or capacitive; when the total coupling polarity presented by the resonator When the coupling polarity is different, the influence of the coupling gap on the coupling strength is also different.

The embodiment of the present application does not limit whether the width of the coupling slit is uniform, for example, the width may be uniform, that is, the width of the sewing slit may be uniform. For example, the width may also be uneven, the width of the coupling slit at the first position is greater than the width of the sewing slit at the second position, that is, the width of the coupling slit may vary. The coupling gap refers to the gap between the metal strip and the boundary of the first metal region.

Secondly, the influence of the length and width of the metal strip on the inductive coupling strength and capacitive coupling strength is introduced. Since both types of coupling exist, the total coupling presented by the resonator is either inductive coupling or capacitive coupling. When the total coupling presented by the resonator When the coupling type is different, the impact of the metal strip on the coupling strength is also different.

Wherein, the length of at least one section of metal strip is the total length between the first end of at least one section of metal strip and the second end of at least one section of metal strip; The overall length between the third ends 33 . The total length of another metal strip is, for example, the total length between the first end 11 and the second end 22 of the metal strip in FIG. 8 .

The first type - the input and output coupling polarity of the resonator is inductive:

The coupling strength of the input-output coupling structure is proportional to the width of at least one section of the metal strip, that is, the wider the width of the metal strip, the greater the total coupling strength; the coupling strength of the input-output coupling structure is inversely proportional to the length of at least one section of the metal strip, namely The longer the length of the metal strip, the lower the overall coupling strength. Among them, the total coupling polarity is inductive.

The second type - the input and output coupling polarity of the resonator is capacitive:

The coupling strength of the input-output coupling structure is inversely proportional to the width of at least one section of the metal strip, that is, the wider the width of the metal strip, the smaller the total coupling strength; the coupling strength of the input-output coupling structure is proportional to the length of at least one section of the metal strip, namely The longer the length of the metal strip, the greater the overall coupling strength. Among them, the total coupling polarity is capacitive.

The embodiment of the present application does not specifically limit whether the width of the metal strip is uniform, for example, the uniform width of the metal strip means that the width of the metal strip is consistent in the extending direction of the metal strip and maintains the same width; for example, the width of the metal strip can be uneven, that is, the metal strip The width of the strips can vary, some positions have wider widths and some positions have narrower widths. Specifically, it can be designed according to the space size of the top surface where the input-output coupling structure is located and the coupling strength requirements. In addition, it may also be designed for the convenience of actual processing, which is not specifically limited in the embodiments of the present application.

In the resonator provided by the embodiment of the present application, the input-output coupling structure includes both capacitive coupling and inductive coupling; the total coupling strength is the difference between the inductive coupling strength and the capacitive coupling strength. If the inductive coupling strength is greater than the capacitive coupling strength, the overall coupling polarity appears inductive. If the capacitive coupling strength is greater than the inductive coupling strength, the overall coupling polarity is capacitive. Both inductive coupling and capacitive coupling will affect the resonant frequency of the resonator. Therefore, the resonant frequency of the resonator can be adjusted by adjusting the combination relationship between inductive coupling and capacitive coupling. In the case of a certain total coupling strength, There are many combinations of capacitive coupling and inductive coupling, and the adjustment is flexible. This can ensure that the required resonant frequency is realized in the resonator with a limited volume, so that the filter including the resonator can meet the requirements of the application scene for the passband and bandwidth. For example, the length of the coupling slit of capacitive coupling can be reduced and the width can be increased, so that the actual processing can be used to improve the tolerance of tolerance, etc.

filter embodiment

Based on the resonator provided in the above embodiments, the embodiment of the present application also provides a filter, which is a dielectric filter. The embodiment of the present application does not limit the specific application scenarios of the dielectric filter. The frequency selection can be performed in any scene, and the type of the filter is not limited, for example, it can be a band-pass filter, a low-pass filter, a high-pass filter, or a high-cut filter. In addition, this embodiment does not limit the specific order of the filter, for example, the second order, third order, fourth order or even fifth order and sixth order, etc., the order can be selected according to actual needs, and the general order corresponds to the number of resonators , for example, the fourth-order filter includes four resonators, and the sixth-order filter includes six resonators. The filter provided by the embodiment of the present application will be described in detail below with reference to the accompanying drawings.

Referring to FIG. 12 , this figure is a schematic diagram of a fourth-order filter provided by an embodiment of the present application.

The filter provided by the embodiment of the present application includes two resonators described in the above embodiments: a first resonator and a second resonator, and at least one third resonator, and the third resonator does not have an input-output coupling structure; The input-output coupling structure of a resonator is used for inputting signals; the third resonator is used for transmitting input signals to the second resonator; the input-output coupling structure of the second resonator is used for outputting signals.

In FIG. 12 , the filter includes four resonators as an example. In addition to the first resonator S and the second resonator W, two third resonators A and B are also included. Wherein, the first resonator S is cascaded with the third resonator A, the third resonator A is cascaded with the third resonator B, and the third resonator B is cascaded with the second resonator W, that is, the first resonator S is used for The external signal is received, and the electromagnetic field of the received signal is coupled to the third resonator A, and the third resonator A couples the signal to the third resonator B through the electromagnetic field, and the third resonator B couples the signal to the second resonator W through the electromagnetic field , the second resonator W sends out the signal, thereby realizing filtering of the signal.

The first resonator S in the filter shown in Figure 12, that is, the first cavity receives external signals, that is, as the input end of the filter, and the last resonator W of the filter, that is, the tail cavity is used to filter the filter The signal is sent out. That is, both the first chamber S and the tail chamber W are provided with an input-output coupling structure.

The input-output coupling structure of the first cavity and the tail cavity of the filter shown in Figure 12 is introduced by taking the structure in Figure 8 as an example. It should be understood that the input-output coupling structure of the filter's first cavity and the tail cavity can also be as shown in Figure 6. The structure shown in the present application is not specifically limited.

In the field of communication, the generally used dielectric filter is a band-pass filter, that is, only signals with frequencies within the band-pass range are allowed to pass through.

For example, the bandwidth of the dielectric filter is greater than or equal to 0.5GHz, such as 6E communication, you can select a signal with a bandwidth of 1.2GHz.

For example, when applied in the communication field, the dielectric filter generally includes at least three third resonators, that is, three resonators in the middle, and at least five resonators in the head and tail resonators.

Since the input and output coupling structures in the first resonator and the second resonator included in the filter provided by the embodiment of the present application both include inductive coupling and capacitive coupling, the frequency selection range of the filter can be flexibly adjusted, which is convenient to obtain a higher frequency range. The frequency band corresponding to the wide bandwidth, for example, the bandwidth of the bandpass filter is the upper side frequency minus the lower side frequency, and the difference between capacitive coupling and inductive coupling can obtain a lot of upper side frequency and lower side frequency, so more bandwidth can be obtained, so It can meet the scenarios with wide bandwidth requirements, such as meeting the communication requirements of 6E with a bandwidth of 1.2GHz.

Communication device embodiment

Based on the filter provided in the foregoing embodiments, the embodiment of the present application further provides a communication device, which will be described in detail below with reference to the accompanying drawings.

Referring to FIG. 13 , the figure is a schematic diagram of a communication device provided by an embodiment of the present application.

The communication device provided in this embodiment includes: the antenna ANT and the dielectric filter FIL introduced above;

Wherein, the antenna ANT is electrically connected to the dielectric filter FIL, and two-way signal transmission can be realized between the two, and the antenna ANT can not only transmit signals, but also receive signals. The dielectric filter FIL can also realize bidirectional transmission of signals.

The dielectric filter FIL is used to band-pass filter the received signal and transmit it to the antenna ANT, so that the antenna ANT wirelessly transmits the filtered signal;

The dielectric filter FIL is also used for band-pass filtering the signal received wirelessly by the antenna ANT.

With the continuous development of wireless communication technology, the bandwidth requirement is getting wider and wider, but the size of each device used in wireless communication is getting smaller and smaller. Therefore, it is necessary to realize the miniaturization of the size of the dielectric filter. All processing steps require the use of filters. The dielectric filter in the communication device provided by the embodiment of the present application can realize a wide bandwidth while ensuring a small size, and is convenient for actual processing. In addition, the embodiment of the present application does not limit whether the antenna ANT and the dielectric filter FIL are integrated together, they may be integrated together, or may be independent components.

It should be understood that in this application, "at least one (item)" means one or more, and "multiple" means two or more. Any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present application that do not deviate from the content of the technical solution of the present application still fall within the protection scope of the technical solution of the present application.

Claims

A resonator, characterized in that the resonator includes a dielectric body and electrodes, wherein the dielectric body is provided with a through hole, the through hole runs through the top surface and the bottom surface of the dielectric body, the top surface and the bottom surface of the dielectric body Between the bottom surfaces are the side surfaces of the dielectric body, the bottom surface and the side surfaces of the dielectric body are covered with a metal layer,

The electrode is arranged on the first side of the dielectric body, and the electrode is insulated from the metal layer on the first side,

On the top surface, a first metal region is provided, wherein the first metal region is connected to the through hole on the top surface;

On the top surface, there is also a second metal area, the second metal area includes at least a section of metal strip, the first end of the second metal area is connected to the electrode, the second end of the second metal area The terminal is connected to the first metal region, and an insulating gap is formed between the second metal region and the first metal region.
The resonator according to claim 1, wherein the second metal region comprises a section of metal strip, the first end of the section of metal strip is connected to the electrode, and the second end of the section of metal strip is connected to the The first metal region, an insulating gap is formed between the second metal region and the first metal region.
The resonator according to claim 1, wherein the second metal region comprises at least the following two sections of metal strips: a first section of metal strip and a second section of metal strip;

The first end of the first section of metal strip is connected to the electrode, the second end of the first section of metal strip is connected to the first metal area, and the connection between the first section of metal strip and the first metal area Insulation gaps are also formed between them;

The first end of the second section of metal strip is connected to the electrode, the second end of the second section of metal strip is connected to the first metal area, and the connection between the second section of metal strip and the first metal area is Insulation gaps are also formed between them.
The resonator according to claim 1, wherein the second metal region comprises at least the following two sections of metal strips: a first section of metal strip and a second section of metal strip;

The first end of the first section of metal strip is connected to the electrode, the second end of the first section of metal strip is connected to the first metal area, and the connection between the first section of metal strip and the first metal area Insulation gaps are also formed between them;

The first end of the second metal strip is connected to the electrode, the second end of the second metal strip is insulated from the first metal area, and the second metal strip is insulated from the first metal area. Insulation gaps are also formed therebetween.
The resonator according to any one of claims 1-4, wherein the second metal region further includes at least one third end, and there is a coupling gap between the at least one third end and the first metal region .
The resonator according to any one of claims 1-5, wherein the second metal region further comprises at least one fourth terminal, and the at least one fourth terminal is electrically connected to the first metal region.
The resonator according to any one of claims 1-6, wherein the at least one section of the metal strip is electrically connected to the first metal region after being bent a preset number of times; the preset number of times is greater than or equal to 1.
The resonator according to any one of claims 1-7, characterized in that, the at least one section of the metal strip has equal widths in the extending direction.
The resonator according to any one of claims 1-8, wherein the insulating gap is used to generate capacitive coupling, and the second end of the second metal region is connected to the first metal region to generate Inductive coupling, the capacitive coupling is greater than the inductive coupling, the resonator exhibits capacitive coupling; the capacitive coupling is smaller than the inductive coupling, the resonator exhibits inductive coupling.
A dielectric filter, characterized in that it comprises two resonators according to any one of claims 1-9: a first resonator and a second resonator, and at least one third resonator, the third the resonator does not have said second metal region;

the second metal region of the first resonator for an input signal;

the third resonator, configured to transmit the input signal to the second resonator;

The second metal region of the second resonator is used to output a signal.
A communication device, characterized by comprising: an antenna and the dielectric filter according to claim 10;

The dielectric filter is configured to band-pass filter the received signal and then transmit it to the antenna, so that the antenna transmits the filtered signal wirelessly;

The dielectric filter is also used for band-pass filtering the signal received by the antenna wirelessly.