Patent Description:
This section merely provides background information related to the present disclosure that is not necessarily prior art.

Multiple-input multiple-output (MIMO) is a technology that dramatically increases data transmission capacity by means of multiple antennas and that employs a spatial multiplexing scheme in which transmitters transmit different types of data through individual transmit antennas and receivers separate the transmitted data through appropriate signal processing. Accordingly, as the number of transmit/receive antennas is increased simultaneously, it is possible to transmit more data through an increase in channel capacity. For example, if <NUM> antennas are used, a channel capacity of approximately <NUM> times is achieved in the same frequency band, compared to a current single antenna system.

A <NUM> LTE-advanced network uses up to <NUM> antennas, and products equipped with <NUM> or <NUM> antennas are currently being developed for a pre-<NUM> network. A <NUM> network expects to use base station equipment with a much larger number of antennas, which is called Massive MIMO. Although cell operation is currently implemented in a <NUM>-dimensional manner, 3D-beamforming becomes possible by introduction of Massive MIMO. Accordingly, the Massive MIMO is also called full dimension MIMO (FD-MIMO).

In the Massive MIMO, as the number of antenna elements increases, the number of transceivers and filters increases as well. As of <NUM>, more than <NUM>,<NUM> base stations have been installed nationwide in Korea. Accordingly, a cavity filter structure is required to minimize a mounting space and facilitate mounting, and an RF signal line connection structure is required to allow cavity filters, which are individually tuned, to provide the same filter characteristics even after being mounted to antennas.

A cavity-structured RF filter includes a resonator composed of a resonant rod, as a conductor, and the like, inside a box structure formed of a metallic conductor, which allows only an electromagnetic field having a natural frequency to exist therein, so that only characteristic frequencies such as ultra-high frequencies pass through the filter by resonance. Such a cavity-structured bandpass filter is widely utilized as a filter for mobile communication base station antennas since it has a low loss of insertion and is advantageous for high power. <CIT> illustrates for example a cavity filter and a connecting structure included therein. The cavity filter includes: an RF signal connecting portion spaced apart, by a predetermined distance, from an outer member having an electrode pad provided on a surface thereof; and a terminal portion configured to electrically connect the electrode pad of the outer member and the RF signal connecting portion so as to absorb assembly tolerance existing at the predetermined distance and to prevent disconnection of the electric flow between the electrode pad and the RF signal connecting portion, wherein the terminal portion includes: first side terminal contacted with the electrode pad; and the second side terminal connected to the RF signal connecting portion. Therefore, the cavity filter can efficiently absorb assembly tolerance which occurs through assembly design, and prevents disconnection of an electric flow, thereby preventing degradation in performance of an antenna device. <CIT> relates to a cavity filter having a slim and compact structure in which a push-pin type RF connector, which is formed such that a terminal is exposed to both sides or one side in a height direction, is embedded so as to reduce a size of an antenna system, quickly perform verification for an individual cavity filter while having high reproducibility, and enable the antenna system to be readily mounted.

An object of the present disclosure is to provide a cavity filter having a slimmer and more compact structure and equipped with an RF connector in a thickness direction in a body thereof.

Another object of the present disclosure is to provide a cavity filter having an RF signal connection structure that is easy to mount and keeps filter's frequency characteristics uniform while ensuring an assembly method capable of minimizing a cumulative amount of assembly tolerances caused when assembling a plurality of filters.

A further object of the present disclosure is to provide a cavity filter capable of preventing an occurrence of signal loss by adding lateral tension while allowing relative movement in the case of a separable RF pin.

The present disclosure is not limited to the above-mentioned objects, and other objects of the present disclosure can be clearly understood by those skilled in the art to which the present disclosure pertains from the following description.

The invention is defined in the independent claim. Further advantageous embodiments are defined in the dependent claims.

A cavity filter according to exemplary embodiments of the present disclosure can achieve various effects as follows.

First, since an RF connector in a thickness direction in a body, it is possible to design a slimmer and more compact structure.

Second, it is possible to design an RF signal connection structure that is easy to mount and keeps filter's frequency characteristics uniform while ensuring an assembly method illustrating an of minimizing a cumulative amount of assembly tolerances caused when assembling a plurality of filters.

Third, it is possible to prevent antenna performance degradation since stable connection is possible by adding lateral tension while allowing relative movement.

Fourth, since an elastic member for eliminating an assembly tolerance is made of one of beryllium copper, stainless steel, and spring steel, it is possible to prevent a deterioration in reliability due to compression reduction ratio.

Reference will now be made in detail to exemplary embodiments of the present disclosure, examples of which are illustrated in the accompanying drawings.

It should be noted that reference numerals are added to the components of the accompanying drawings to facilitate understanding of the embodiments described below and the same reference numbers will be used throughout the drawings to refer to the same or like parts wherever possible. In certain embodiments, detailed descriptions of constructions or functions well known in the art may be omitted to avoid obscuring appreciation of the disclosure by a person of ordinary skill in the art.

The terms such as "first", "second", "A", "B", "(a)", and "(b)" may be used herein to describe components in the embodiments of the present disclosure. These terms are not used to define an essence, order or sequence of a corresponding component but used merely to distinguish the corresponding component from other component(s). Unless otherwise defined, all terms, including technical and scientific terms, used herein have the same meaning as commonly understood by one of ordinary skill in the art.

<FIG> is a diagram illustrating an exemplary stacked structure of Massive MIMO antennas.

<FIG> illustrates only an exemplary appearance of an antenna device <NUM> equipped with an antenna assembly including cavity filters, and does not limit the appearance of the antenna device at the time of actual stacking operation.

The antenna device <NUM> includes a housing <NUM> having a heat sink formed therein, and a radome <NUM> coupled to the housing <NUM>. An antenna assembly may be provided between the housing <NUM> and the radome <NUM>.

A power supply unit (PSU) <NUM> is coupled to the lower portion of the housing <NUM>, for example, through a docking structure. The power supply unit <NUM> provides operating power to operate communication components included in the antenna assembly.

The antenna assembly typically has a structure in which a plurality of antenna elements <NUM> are arranged on the front surface of an antenna board <NUM>, the same number of cavity filters <NUM> as the number of antenna elements <NUM> is arranged on the back surface of the antenna board <NUM>, and a related PCB <NUM> is subsequently stacked thereon. The cavity filters <NUM> may be prepared to be tuned and verified in detail such that each individual cavity filter has a frequency characteristic suitable for the specifications thereof before mounting. It is preferable that such tuning and verification be performed rapidly in the same characteristic environment as the mounting.

<FIG> is a cross-sectional diagram illustrating a state in which cavity filters are stacked between an antenna board and a control board according to an embodiment of the present disclosure.

Referring to <FIG>, the cavity filters, which are designated by reference numeral <NUM>, according to the embodiment of the present disclosure may exclude typical RF connectors <NUM> illustrated in <FIG>. Thus, it is possible to provide an antenna structure that makes it easier to connect and has a lower height profile.

In addition, RF connections are provided in a height direction on both sides of an antenna device and are connected by the cavity filters <NUM> according to the embodiment of the present disclosure. Therefore, it is advantageous to keep the RF connections constant even though vibration and thermal deformation occur in an antenna board <NUM> or a PCB <NUM>, resulting in no change in frequency characteristics.

<FIG> is a bottom view illustrating a structure of one cavity filter according to the embodiment of the present disclosure. <FIG> is an exploded perspective view illustrating a state in which a filter module and a terminal section, as partial components of the cavity filter, are separated from each other according to the embodiment of the present disclosure. <FIG> is an exploded perspective view of <FIG>. <FIG> is an exploded perspective view illustrating the cavity filter according to the embodiment of the present disclosure. <FIG> and <FIG> are partial cross-sectional views of <FIG> and illustrate states before and after bonding to the PCB. <FIG> are modifications of <FIG> and <FIG>.

Referring to <FIG>, each of the cavity filters <NUM> according to the embodiment of the present disclosure includes an RF signal connector (no reference numeral), a first casing (no reference numeral) having a hollow defined therein, a second casing (no reference numeral) covering the first casing, terminal sections <NUM> (see <FIG>) provided in the height direction of the cavity filter <NUM> on both longitudinal sides of the first casing, and a filter module <NUM> having assembly holes <NUM> provided in each of the terminal sections <NUM>. Each of the terminal sections <NUM> passes through a terminal insertion port <NUM> provided in the first casing and electrically connects an electrode pad (no reference numeral) of an external member <NUM>, such as an antenna board or a PCB, to the RF signal connector.

When the terminal section <NUM> is supported at the lower end thereof in the drawing by the RF signal connector (not shown) and is closely bonded at the upper side thereof to the antenna board or the PCB <NUM>, the terminal section <NUM> may be always in contact with the external member <NUM>(especially, the electrode pad provided on one surface thereof) and may be elastically supported to eliminate an assembly tolerance existing in the terminal insertion port <NUM> of a filter body <NUM> to be described later.

That is, the cavity filter <NUM> according to the present disclosure may be implemented in specific embodiments, in which the terminal section <NUM> is separated into one terminal <NUM> and the other terminal <NUM>, is shaped to add lateral tension, and absorbs an assembly tolerance, as described later.

In more detail, the terminal section <NUM> may be separated into two upper and lower members <NUM> and <NUM> (see <FIG>), as illustrated in <FIG>, and may be of a separation type in which a portion of one of the two members is inserted into a portion of the other member. In an embodiment of the present disclosure, it is adopted that a portion of the upper end of the other terminal <NUM> is inserted into the lower portion of one terminal <NUM>. Of course, the opposite structure is also available.

In general, in the case that the terminal section <NUM> is provided as an integral filter although not illustrated in the drawings, when an assembler applies a predetermined assembly force to the terminal section <NUM> in order to eliminate an assembly tolerance, a constituent part of the terminal section <NUM> is provided as an elastic body that is elastically deformed. However, the integral filter as the terminal section <NUM> does not require a separate shape design for separately adding lateral tension since an interruption of electrical flow between one end and the other end of the filter is not predicted.

In contrast, in the case that the terminal section <NUM> is provided as a separable filter with two separated members, the assembly tolerance may be eliminated by a separate elastic member 80A/80B configured such that the entire length thereof is contractible as the separated terminals <NUM> and <NUM> are moved to overlap with each other by the above-mentioned predetermined assembly force whereas the entire length thereof is extended and restored when the assembly force is removed. However, since the terminal section <NUM> is separated into one terminal <NUM> and the other terminal <NUM>, there is a risk of interrupting an electrical flow when the terminals are moved to overlap with each other. Therefore, either of the terminals <NUM> and <NUM> may be provided as an elastic body, or a separate shape change to add lateral tension may be necessarily required.

Here, the term "lateral tension" may be defined as a force that allows one of the terminals <NUM> and <NUM> to be directed toward the other terminal in a direction different from the longitudinal direction in order to prevent the interruption of electrical flow between one terminal <NUM> and the other terminal <NUM> as described above.

Meanwhile, due to the characteristics of the antenna device, during the design of shape change of the above terminal section <NUM>, an impedance matching design in the terminal insertion port <NUM> should be performed in parallel. However, the cavity filter <NUM> according to the embodiments of the present disclosure will be described below on the promise that the impedance matching in the terminal insertion port <NUM> has been achieved. Therefore, in the configuration of the cavity filter according to the embodiments of the present disclosure described with reference to <FIG> and the subsequent drawings, components, such as a dielectric body <NUM> or a reinforcing plate, inserted together with the terminal section <NUM> into the terminal insertion port <NUM> may have different shapes according to the impedance matching design.

Referring to <FIG>, the cavity filter <NUM> according to the embodiment of the present disclosure includes the RF signal connector spaced apart at a predetermined distance from the external member <NUM> having the electrode pad (no reference numeral) on one surface thereof, and the terminal section <NUM> configured to electrically connect the electrode pad of the external member <NUM> to the RF signal connector and to eliminate the assembly tolerance existing at the predetermined distance while preventing the interruption of electrical flow between the electrode pad and a resonant element.

Here, the external member <NUM> may be one of an antenna board or power amplifier (PA) having antenna elements arranged on the other surface thereof, a digital board, and a PCB equipped with TX calibration as an integrated one-board, as illustrated in <FIG>.

Hereinafter, as illustrated in <FIG>, the external configuration of the cavity filter <NUM> according to the embodiments of the present disclosure is not divided into the first casing and the second casing, but is collectively referred to as a filter body, which is designated by reference numeral <NUM>, having the terminal insertion port <NUM>. The filter body <NUM> may be made of a dielectric material that is easy for an impedance matching design therein (see reference numeral "<NUM>" in <FIG> and <FIG>). Preferably, the filter body <NUM> may be made of Teflon.

As illustrated in <FIG>, the filter body <NUM> may be provided with the terminal insertion port <NUM> in a hollow form. The terminal insertion port <NUM> may have a shape suitable for an impedance matching design.

A washer installation part <NUM> may be grooved on one surface of the filter body <NUM>, especially, on one surface on which one terminal <NUM> of the terminal section <NUM> is provided. The washer installation part <NUM> may be grooved to have a larger inner diameter than a terminal installation hole <NUM> in order to latch the outer edge of a star washer <NUM> to be described later and prevent it from being separated upward.

In addition, the cavity filter <NUM> according to the example of the present disclosure may further include the star washer <NUM> that is fixedly installed in the washer installation part <NUM>.

The star washer <NUM> may include a ring-shaped fixed end <NUM> fixed to the washer installation part <NUM>, and a plurality of support ends <NUM> inclined upward toward the center of the electrode pad of the antenna board or PCB <NUM> from the fixed end <NUM>.

The star washer <NUM> may be configured such that, when the assembler assembles the cavity filter <NUM> according to the embodiment of the present disclosure to the antenna board or the PCB <NUM>, the support ends <NUM> are supported by one surface of the antenna board or PCB <NUM> while applying an elastic force against the fastening force of fastening members (not shown) through the assembly holes <NUM>. The addition of the elastic force by the support ends <NUM> serves to eliminate the assembly tolerance existing between the antenna board or the PCB <NUM> and the cavity filter <NUM> according to the embodiment of the present disclosure.

However, the assembly tolerance absorbed by the star washer <NUM> exists in the terminal insertion port <NUM>, and is a concept different from the assembly tolerance absorbed by the terminal section <NUM>, as described later. That is, the cavity filter according to the embodiment of the present disclosure may be designed to absorb the overall assembly tolerance at at least two locations by separate members in a single assembly process, thereby achieving more stable bonding.

In the cavity filter <NUM> according to the embodiment of the present disclosure, the terminal section <NUM> includes one terminal <NUM> in contact with the electrode pad of the external member <NUM>, and the other terminal <NUM> fixed to a solder hole <NUM> formed in a portion, extending in the form of a plate, as the RF signal connector, as illustrated in <FIG>. However, the other terminal <NUM> is not necessarily directly solder-bonded to the RF signal connector, but may be coupled to another electrically-connected conductive member.

Here, one of the terminals <NUM> and <NUM> may be inserted into the other terminal, so that portions of the respective ends thereof may overlap with each other by a predetermined length during assembly.

The cavity filter <NUM> according to the embodiment of the present disclosure may have a structure in which the upper side of the other terminal <NUM> is inserted into the lower side of one terminal <NUM> in the drawings (especially, see <FIG> and <FIG>). To this end, the lower end of one terminal <NUM> may be provided in the form of a hollow tube such that the upper end of the other terminal <NUM> is inserted into the lower end of one terminal <NUM>.

When the terminal section <NUM> composed of one terminal <NUM> and the other terminal <NUM> is installed in the terminal insertion port <NUM>, the dielectric body <NUM> made of a dielectric material to surround the terminal section <NUM> may be inserted into the terminal insertion port <NUM> for impedance matching therein.

The dielectric body <NUM> may be made of Teflon. However, the material of the dielectric body <NUM> is not limited to Teflon, and any material having a dielectric constant allowing impedance matching in the terminal insertion port <NUM> may be used for the dielectric body <NUM>.

In addition, the dielectric body <NUM> may have the terminal installation hole <NUM>, which is a hollow space permitting vertical communication at the center thereof and substantially equipped with the terminal section <NUM>.

The dielectric body <NUM> may further include a lower inner dielectric <NUM> formed integrally with the other terminal <NUM> of the terminal section <NUM> by injection molding, and an upper inner dielectric <NUM> formed integrally with one terminal <NUM> of the terminal section <NUM> by injection molding.

The lower inner dielectric <NUM> may have a terminal through-hole 73a, which is formed when it is formed integrally with the other terminal <NUM> by injection molding and permits passage of the other terminal <NUM>. Likewise, the upper inner dielectric <NUM> may have a terminal through-hole 72a, which is formed when it is formed integrally with one terminal <NUM> by injection molding and permits passage of one terminal <NUM>.

The upper inner dielectric <NUM> may be formed to support and surround a portion of the outer peripheral surface of one terminal <NUM>, and the lower inner dielectric <NUM> may be formed to support and surround a portion of the outer peripheral surface of the other terminal <NUM>.

However, the dielectrics <NUM> and <NUM> are not necessarily manufactured integrally with the respective terminals <NUM> and <NUM> of the terminal section <NUM> by injection molding.

That is, the upper and lower inner dielectrics <NUM> and <NUM> may be separately formed to have the respective terminal through-holes 72a and 73a and may be inserted into the terminal installation hole <NUM> for assembly.

The upper internal dielectric <NUM> may be disposed to achieve impedance matching in the terminal insertion port <NUM>, and may be preferably spaced apart from the dielectric body <NUM> so as to be vertically movable relative to the other fixed terminal <NUM> corresponding to one terminal <NUM>. The lower internal dielectric <NUM> may be disposed to achieve impedance matching in the terminal installation hole <NUM>, and may be in contact with the dielectric body <NUM> so as to easily fix the other terminal <NUM>.

The dielectric body <NUM>, the lower inner dielectric <NUM>, and the upper inner dielectric <NUM> described above may be designed individually or in combination with each other to suit the overall impedance matching in the filter body <NUM>.

Meanwhile, a second elastic member installation end <NUM> may be formed at the upper portion of the terminal installation hole <NUM> of the dielectric body <NUM>. The second elastic member installation end <NUM> may be stepped to be larger than the diameter of the terminal installation hole <NUM> therearound so that an edge end of a second elastic member 80B of the elastic member 80A/80B to be described later is installed at and supported by the second elastic member installation end <NUM>. Hereinafter, for convenience, a space in which the lower end of one terminal <NUM> is located will be defined and described as a terminal installation groove <NUM>. Assuming that the second elastic member installation end <NUM> is referred to a portion stepped smaller than the terminal installation groove <NUM>, the terminal installation groove <NUM> may be referred to as a portion stepped larger than the second elastic member installation end <NUM>.

Lower support ends 85b of the second elastic member 80B of the elastic member 80A/80B according to another embodiment may be installed in contact with the bottom of the second elastic member installation end <NUM>. This will be described in more detail later.

In addition, around the terminal installation hole <NUM> positioned higher than the bottom of the terminal installation groove <NUM>, the first elastic member installation end <NUM> may be stepped to have a diameter larger than the diameter of the second elastic member installation end <NUM>. A first elastic member 80A of the elastic member 80A/80B according to the embodiment may be installed at the first elastic member installation end <NUM>. This will be described in more detail later.

<FIG> is a perspective view illustrating the elastic member according to the embodiment in the configuration of <FIG>. <FIG> is a perspective view illustrating a modification of the elastic member of <FIG>. <FIG> is a perspective view illustrating the elastic member according to another embodiment in the configuration of <FIG>. <FIG> is a partial cross-sectional view of <FIG> where the elastic member of <FIG> is provided.

As illustrated in <FIG>, the cavity filter <NUM> according to the embodiment of the present disclosure may further include the elastic member 80A/80B having an edge whose portion is supported by the dielectric body <NUM>. The elastic member 80A/80B elastically supports the terminal section <NUM> by means of an operation in which a hollow portion 81a/81b of the elastic member 80A/80B is vertically deformed relative to the portion of the edge when an assembly force is applied to the terminal section <NUM> supported to pass through the hollow portion 81a/81b.

Here, the elastic member 80A/80B may be made of one of beryllium copper (BeCu), stainless steel (SUS), and spring steel. The elastic member 80A/80B may be made of silicone of materials typically used therefor. However, silicone may cause a deterioration in elasticity due to a predetermined compression reduction ratio after a long period of use, resulting in a deterioration in long-term reliability of the cavity filter.

Accordingly, in the cavity filter <NUM> according to the embodiment of the present disclosure, the elastic member 80A/80B is made of, instead of silicone, one of the above-mentioned beryllium copper, stainless steel, and spring steel that are usable for a long period of time to secure long-term reliability while decreasing a degradation of compression reduction ratio although its own elasticity is low.

As illustrated in <FIG>, the elastic member 80A/80B may include the first elastic member 80A in the form of a disk, having a hollow portion 81a, a plurality of outer edges 84a supported by the first elastic member installation end <NUM>, and a plurality of inner edges 85a to which one terminal <NUM> of the terminal section <NUM> is latched.

As illustrated in <FIG>, the first elastic member 80A may be configured such that the outer edges 84a and the inner edges 85a are separated by outer cuts 82a each formed by cutting a predetermined length toward the hollow portion 81a from the outer peripheral surface of the elastic member and inner cuts 83a each formed by cutting a predetermined length toward the outer peripheral surface of the elastic member from the hollow portion 81a, respectively.

Accordingly, the outer edges 84a are separated by the outer cuts 82a, and the inner edges 85a are separated by the inner cuts 83a. At the same time, the first elastic member 80A may be in the form of a zigzag ring in which each of the outer edges 84a and an adjacent one of the inner edges 85a are interconnected.

When an assembly force is applied to the first elastic member 80A through one terminal <NUM> of the supported terminal section <NUM>, the inner edges 85a are elastically deformed downward with respect to the outer edges 84a supported by the second elastic member installation end <NUM>, thereby elastically supporting the terminal section <NUM>.

That is, as illustrated in <FIG>, when no external force such as an assembly force is applied to the outer and inner edges 84a and 85a of the first elastic member 80A, the terminal section <NUM> is supported in parallel with a connection portion connecting the outer and inner edges. Then, as illustrated in <FIG>, when an external force such as a predetermined assembly force is applied to the first elastic member 80A, the inner edges 85a together with the terminal section <NUM> is moved downward in a direction in which the assembly force is applied, and the connection portion connecting the outer and inner edges 84a and 85a is deformed in shape so as to be inclined inward and downward, thereby elastically supporting the terminal section <NUM>.

However, in the cavity filter <NUM> according to the embodiment of the present disclosure, the first elastic member 80A should not be limited to the shapes of <FIG>, <FIG>, and <FIG>.

That is, as illustrated in <FIG>, and <FIG>, the first elastic member 80A may be configured such that the outer edges 84a are bent outward at a predetermined angle with respect to the inner edges 85a. Making the support surfaces of the outer and inner edges 84a and 85a deviate from each other is to add a more reliable elastic force than making the support surfaces parallel as illustrated in <FIG>, <FIG>, and <FIG>.

However, since the modification of the first elastic member 80A illustrates that the outer edges 84a are bent with respect to the inner edges 85a, it is required that no crack and overall dimension change occur in the bent portion therebetween.

In addition, as illustrated in <FIG>, when the filter body <NUM> provided with the modified first elastic member 80A is pressed against the electrode pad of the external member <NUM> to provide a predetermined assembly force, it is possible to secure a robust support force for the first elastic member installation end <NUM> by the bent outer edges 84a.

Meanwhile, as illustrated in <FIG>, the elastic member may further include the second elastic member 80B in the form of a disk, having an elastic part (no reference numeral) provided with a hollow portion 81b and a plurality of lower support ends 85b supported by the second elastic member installation end <NUM>, and a boss 84b extending downward from the elastic part so as to surround the outer peripheral surface of one terminal <NUM> of the terminal section <NUM> passing through the hollow portion 81b.

As illustrated in <FIG>, the second elastic member 80B may be elastically deformed by a plurality of inner elastic cuts 83b circumferentially arranged and each vertically formed around the hollow portion 81b and a plurality of outer elastic cuts 82b circumferentially arranged and each vertically formed around the inner elastic cuts 83b.

When an assembly force is applied to the second elastic member 80B through one terminal <NUM> of the supported terminal section <NUM>, the inner edge of the elastic part at which the hollow portion 81b is located is elastically deformed downward with respect to the edge of the elastic part supported by the second elastic member installation end <NUM>, thereby elastically supporting the terminal section <NUM>.

When a contact portion <NUM>, which is the tip of one terminal <NUM> of the terminal section <NUM>, is pressed against and assembled to the electrode pad of the external member <NUM> through the elastic support action of the elastic member 80A/80B, the elastic member is elastically deformed to eliminate the assembly tolerance existing in the terminal insertion port <NUM> as described above, and then applies an elastic force to one terminal <NUM> of the terminal section <NUM> such that the contact portion <NUM> of one terminal <NUM> is continuously in contact with the electrode pad.

Meanwhile, the smaller the contact area of the contact portion <NUM> in contact with the antenna board or the PCB <NUM>, the better one terminal <NUM> becomes. Accordingly, the contact portion <NUM>, which is the tip of one terminal <NUM>, may have a conical shape whose width becomes narrower upward, as illustrated in <FIG>.

When the assembler provides an assembly force by means of an operation in which the contact portion <NUM> as the tip of one terminal <NUM> comes into contact with the electrode pad of the external member <NUM>, one terminal <NUM> may be movable up and down on the drawing in the terminal insertion port <NUM> by the elastic member 80A/80B.

In addition, the lower end <NUM> of one terminal <NUM> into which the upper end of the other terminal <NUM> is inserted may be provided with a plurality of tension cuts <NUM> that are vertically elongated. The tension cuts <NUM> may be formed to divide the lower end <NUM> of one terminal <NUM> in the form of a hollow tube into a plurality of pieces.

The tension cuts <NUM> serve to add the above-mentioned lateral tension by allowing the lower end <NUM> of one terminal <NUM> to be pressed against the outer circumference of the upper end <NUM> of the other terminal <NUM> accommodated therein. Since the dielectric body <NUM> is provided to inwardly support the outer peripheral surface of one terminal <NUM> on which the tension cuts <NUM> are formed, the inner surface of the lower end <NUM> of the one terminal <NUM>, which is cut by the tension cuts <NUM>, is always in close contact with the outer peripheral surface of the upper end <NUM> of the other terminal <NUM> accommodated therein.

The addition of the lateral tension by the tension cuts <NUM> as described above can prevent the interruption of electrical flow between two separated terminals of the terminal section <NUM> in advance.

On the other hand, the tip of the other terminal <NUM> of the terminal section <NUM> may have a pointed shape such that it is easily inserted into the hollow tube of one terminal <NUM>, and the lower end of the other terminal <NUM> may be fixed to the above-mentioned RF signal connector.

Accordingly, when one terminal <NUM> is moved downward by the assembly force with the lower end of the other terminal <NUM> fixed to the RF signal connector, the other terminal <NUM> is inserted further deeply into the lower end <NUM> in the form of a hollow tube of one terminal <NUM>, with the consequence that the assembly tolerance existing in the terminal insertion port <NUM> can be absorbed by extending and contracting the vertical length of the terminal section <NUM> as a whole.

Meanwhile, as illustrated in <FIG>, <FIG>, <FIG>, and <FIG>, when no assembly force is provided, one terminal <NUM> may be configured such that the contact portion <NUM> has a height to protrude higher than the support ends <NUM> of the star washer <NUM>.

The assembly tolerance absorption process according to the assembly of the cavity filters <NUM> according to the embodiment of the present disclosure having such a configuration will be described with reference to the accompanying drawings (in particular, <FIG> and <FIG> ).

First, as illustrated in <FIG> and <FIG>, the cavity filters <NUM> according to the embodiment of the present invention are pressed against one surface of the external member <NUM> such as the antenna board or the PCB having with the electrode pad, and the fastening members (not shown) are then fastened to the assembly holes, in order to apply a predetermined assembly force to the cavity filters <NUM>. However, it is not necessary to press the cavity filters <NUM> against one surface of the antenna board or the PCB <NUM>. On the contrary, it is also possible to apply an assembly force by pressing one surface of the external member <NUM> such as the antenna board or the PCB against the cavity filters <NUM> arranged at predetermined intervals.

Then, the distance between the antenna board or the PCB <NUM> and each of the cavity filters <NUM> according to the embodiment of the present disclosure is reduced, and at the same time, the support ends <NUM> of the star washer <NUM> is deformed in shape by the above-mentioned fastening force. As a result, the assembly tolerance existing between the antenna board or the PCB <NUM> and the cavity filter <NUM> according to the embodiment of the present disclosure is primarily absorbed.

At the same time, by means of the elastic support operation of the elastic member 80A/80B while one terminal <NUM> of the terminal section <NUM> is pressed by one surface of the external member <NUM> such as the antenna board or the PCB so as to move a predetermined distance to the other terminal <NUM> in the terminal insertion port <NUM>, the assembly tolerance existing in the terminal insertion port <NUM> of the cavity filter <NUM> according to the embodiment of the present disclosure is secondarily absorbed.

In this case, the interruption of electrical flow between one terminal <NUM> and the other terminal <NUM> can be prevented since the lateral tension is added by tension cuts <NUM> to the upper end of the other terminal <NUM> inserted into the lower end in the form of a hollow tube of one terminal <NUM>. Therefore, it is possible to prevent the signal performance degradation of the cavity filter <NUM> according to the embodiment of the present disclosure.

Claim 1:
A cavity filter (<NUM>) comprising:
an RF signal connector configured to be spaced apart at a predetermined distance from an external member (<NUM>) having an electrode pad on one surface thereof;
a terminal section (<NUM>) configured to electrically connect the electrode pad of the external member (<NUM>) to the RF signal connector and to absorb an assembly tolerance existing at the predetermined distance while preventing an interruption of electrical flow between the electrode pad and the RF signal connector,
a filter body (<NUM>) having the RF signal connector therein;
a terminal insertion port (<NUM>) formed in the filter body (<NUM>);
a dielectric body (<NUM>) inserted into the terminal insertion port (<NUM>) to surround the terminal section (<NUM>), wherein the terminal section (<NUM>) is inserted into the terminal insertion port (<NUM>) through the dielectric body (<NUM>) ; and and
an elastic member (80A, 80B) in the form of a disk having an edge (84a, 85b) whose portion is supported by the dielectric body (<NUM>), the elastic member (80A, 80B) being configured to elastically support the terminal section (<NUM>) by means of an operation in which a hollow portion (81a, 81b) of the elastic member (80A, 80B) is vertically deformed relative to the portion of the edge (84a, 85b) when an assembly force is applied to the terminal section (<NUM>) supported to pass through the hollow portion,
wherein the terminal section (<NUM>) comprises:
one terminal (<NUM>) configured to come into contact with the electrode pad; and
another terminal (<NUM>) connected to the RF signal connector.