KR20150016069A - Variable high frequency filter device and assembly - Google Patents

Abstract

In a variable filter assembly capable of changing a central frequency and a band width, the variable filter assembly includes a casing which has cavities which are formed by the combination of a cover and a body and are separated by cavity walls, an input port and an output port which penetrate both sides in the longitudinal direction of the casing, a resonator which is attached to the lower side of the cavity, respectively, tuning elements which include a head and a bar which penetrates the cover to be inserted into the resonator, and cams which are respectively located on the head and touch the head. The insertion of the bar can be controlled by the cam.

Description

[0001] VARIABLE HIGH FREQUENCY FILTER DEVICE AND ASSEMBLY [0002]

The following embodiments relate to a high frequency filter device and an assembly capable of changing a center frequency and a bandwidth.

Generally, a high-frequency filter is generally tuned after fabrication / assembly, and the result of the tuning is fixed with an adhesive or the like so that the performance of the final implemented filter is not changed in accordance with external environment change or time. Recently, a system using a plurality of bandwidths in a plurality of bands has been required. For this purpose, a filter bank is formed by fabricating all the filters satisfying each requirement, that is, different frequencies and bandwidths, A system that enables a filter having a desired frequency and bandwidth to be used by changing the path of a radio wave is applied.

In this case, if one filter can change the frequency and bandwidth as needed, a filter bank that takes up a lot of money, space, and weight can be replaced with a small number of filters.

(Patent Document 10-2003-000997602) discloses a technique for changing a center frequency and a bandwidth of a filter in a wide band so that not only a resonance frequency of a resonator but also a coupling amount between resonators can be controlled by using a varicap diode , Which is an adjustment of the tuning element by an electrical method.

Unlike the conventional mechanical methods, in changing the center frequency or bandwidth of a filter using a variable filter device or assembly according to an embodiment, not only the resonance frequency of the resonator is changed, but the amount of coupling between each resonator I want to change it.

In addition, by using the variable filter device or the assembly according to an embodiment, the performance degradation of the filter due to the change of the center frequency or the bandwidth of the filter is minimized, and the automatic variable filter is implemented using only one motor, .

The tunable filter may include a casing defining a cavity therein by coupling the cover and the body, a resonator attached to the lower surface of the cavity, a head, The rod including a tuning element through the cover and insertable into the resonator, and a cam located on and in contact with the head, the degree of insertion of the rod being adjustable by the cam .

According to one aspect, the cam may be arranged so that the axis of the tuning element and the cam center point are in line.

According to one aspect, the variable filter device further comprises a lever disposed between the head and the cam after offsetting the cam, the head abutting a lower surface of the lever, The lever may further include a rotation center, and the distance between the rotation center and the cam may be larger than the distance between the rotation center and the head.

According to one aspect, the variable filter device further comprises a compressed spring disposed between the head and the top of the cover, wherein the compressed spring can always exert a force in a direction of pushing the head away from the cover.

According to one aspect, the profile of the cam may have four points of action at different distances from the center of the cam each time it rotates 90 degrees.

According to one aspect, the profile of the cam may have n operating points at different distances from the center of the cam each time it rotates 360 / n.

According to one aspect, the variable filter device further includes a cam shaft and a shaft fixing member passing through the center of the cam. And the camshaft may be disposed in contact with the head by the shaft fixing member.

The variable filter assembly according to one embodiment, wherein the variable filter assembly forms a plurality of cavities therein by coupling a cover and a body, the plurality of cavities being formed in a plurality of cavity walls An input port and an output port attached to both sides of the casing in the lengthwise direction thereof, a resonator formed on or integrated with each of the cavity bottom surfaces, a head and a rod, the rod passing through the cover A plurality of tuning elements that can be inserted into the resonator, and a plurality of cams located on each of the heads and in contact with the head, the degree of insertion of the rods being adjustable by the cam.

According to one aspect, the cavity wall comprises an iris composed of an empty space in the cavity wall, the variable filter assembly comprising a head and a rod, the rod passing through the cover and having a plurality of couples Further comprising a ring element, each head of the coupling element being in contact with a corresponding cam.

According to one aspect, the cam may be arranged so that the axis of the tuning element and the coupling element and the center point of each cam corresponding thereto are aligned.

According to one aspect, the variable filter assembly may further include a camshaft connecting the cams located on the respective tuning element and the coupling element.

According to one aspect, the variable filter assembly may further include a cam drive motor that rotates the camshaft by external power.

According to one aspect of the present invention, the variable filter assembly further includes a motor fixing member disposed at one longitudinal end of the casing, and the motor fixing member can position the cam driving motor at a height corresponding to the camshaft have.

According to one aspect, the variable filter assembly may further include a drive coupling that transmits a driving force of the cam drive motor to the camshaft.

According to one aspect, the variable filter assembly further comprises a compressed spring disposed between the head of each tuning element and the coupling element and the cover of the casing, and the compressed spring always urges the head in a direction Can act as a force.

According to one aspect, the variable filter assembly further comprises a plurality of levers disposed between each of the heads and the cam after offsetting the cam, the heads abutting the lower surface of the leverage, The lever may further include a rotation center, and the distance between the rotation center and the cam may be larger than the distance between the rotation center and the head.

According to one aspect, the variable filter assembly may further include a camshaft connecting cams that are in contact with upper surfaces of the plurality of levers.

According to one aspect, the variable filter assembly may further include a cam drive motor that rotates the camshaft by external power.

According to one aspect, the profile of the cam may have n operating points at different distances from the center of the cam each time it rotates 360 / n.

The variable filter device or the assembly according to the embodiment can adjust not only the center frequency of the resonators but also the coupling amount between the resonators, as opposed to the conventional mechanical method, which determines the performance of the filter, It is possible to maintain a very good filter performance despite the center frequency shift of the filter.

 Further, when the variable filter device or assembly according to one embodiment is used, all the tuning elements are adjusted at the same time by using one motor, so that the overall volume and weight are not greatly increased.

Further, by using the variable filter device or the assembly according to the embodiment, since the variable filter can be made by adding only the cam system without changing the original shape of the filter, no additional filter design is required.

Fig. 1 is a cut-away sectional view showing an internal view of a combline filter to be used in the variable filter device according to the first embodiment.
2 is a cross-sectional detail view of an enlarged portion of a combline filter to be used in the variable filter device according to the first embodiment.
3 is a cross-sectional view schematically showing a cross section of a variable filter device including a cam according to the first embodiment.
4 is a perspective view schematically illustrating a variable filter assembly including a cam according to the first embodiment.
5 is a cross-sectional view schematically showing a cross section of a variable filter assembly including a cam according to the first embodiment.
6 is a cross-sectional view schematically showing a cross section of a variable filter device including a lever and a cam according to the second embodiment.
7 is a graph illustrating four filter performances implemented using a variable filter assembly according to one embodiment.

Hereinafter, configurations and applications according to embodiments of the present invention will be described in detail with reference to the accompanying drawings. DETAILED DESCRIPTION OF THE INVENTION The following description is one of many aspects of the claimed invention and the following description forms part of a detailed description of the present invention.

In the following description, well-known functions or constructions are not described in detail for the sake of clarity and conciseness.

1 is a cross-sectional view showing an inner appearance of a variable filter device 100 according to a first embodiment. Among the high-frequency filters, the combline filter is one of popular filters because it has the advantages of high quality factor (Q-factor), ease of tuning, wide tuning range, and relatively small size. And is particularly suitable for application to one embodiment because of its wide tuning range. Such a combline filter is structured as shown in FIG.

1 shows a cross section of a fifth order variable filter device 100 and includes two input and output ports 140 including five SMA connectors 141 and a connector feed 142, five cavities 120, A cavity wall 123 separating the space of each cavity 120, a resonator 121 in the cavity 120 and a tuning element 132 for adjusting the electrical length of the resonator 121, An iris 124 composed of an opening surface which is an empty space of the iris 124, and a coupling element 133 which adjusts the area of the opening surface of the iris 124. The combline variable filter device 100 can adjust the insertion depth of the tuning element 132 and the coupling elements 133 to realize a filter performance of a desired bandwidth at a desired frequency.

2 is a cross-sectional detail view of an enlarged view of a portion where the input / output port 141 is visible in the variable filter device 100 according to the first embodiment. A coupling element 133 for adjusting the area of the opening surface of the iris 124, a resonator 121 in the cavity 120, and an input / output coupling element 131, which can be inserted into the input / output coupling structure 122, There is shown a variable filter device 100 that includes a tuning element 132 that adjusts the electrical length of the resonator 121.

The variable filter device 100 includes an input / output coupling element support 113 for supporting movement of the element 131 to vertically insert the input / output coupling element 131 into the cover 111, A tuning element support 114 for supporting the movement of the element 132 to insert the element 132 vertically into the cover 111 and a coupling element 133 for coupling the coupling element 133 to the opening of the iris 124 And a coupling element support 115 for supporting the movement of the element 131 for insertion into the spherical surface.

In the case of a non-variable filter device, only the tuning element 132 for adjusting the electrical length of the resonator and the coupling element 133 for adjusting the resonance period coupling amount are used to implement the desired filter performance. However, if the center frequency and bandwidth are changed by more than a certain amount, the input / output coupling amount should be adjusted so that the filter performance such as insertion loss does not deteriorate greatly. Therefore, it is possible to further adjust the input / output coupling amount by further including the input / output coupling element 131. That is, as shown in FIG. 2, the input / output coupling amount can be adjusted by adjusting the distance between the input / output coupling element and the input / output coupling structure 122.

3 is a cross-sectional view schematically showing a cross section of the variable filter device 100 including the cam 152 according to the first embodiment.

The variable filter device 100 capable of changing the center frequency and the bandwidth includes a casing 110 that forms a cavity 121 inside by coupling the cover 111 and the body 112, A tuning element (132) attached to the surface, a head and a rod, the rod passing through the cover (111) and insertable into the resonator, and a tuning element Includes a cam (152), and the degree of insertion of the rod can be adjusted by the cam (152).

The cam system 150 can be used as shown in FIG. 3 as a method for adjusting the insertion amount of the tuning elements 131, 132, 133 of the combline variable filter apparatus 100 at once. As shown in FIG. 3, the tuning element 132 is located at the upper end of the casing 110, and the tuning element 132 moves up and down as the cam 152 rotates. Thus, the tuning elements 131, 132, 133 may be followers of a conventional cam system 150.

When the cam 152 is rotated in the reference position, the tuning element 132 can be further inserted by the pressure of the cam 152, and the insertion depth can be reduced by a force pushing upward while the spring is about to be tensioned. The tuning element 132 is guided by a tuning element support 114 in the form of a bushing so that the tuning element can only be repeatedly moved up and down in a stable manner, and unlike a typical tuning screw, there is no thread in the tuning element 132 Do not.

Since the height of the tuning element 132 to be controlled by the cam 152 is determined based on four points spaced 90 degrees apart from the center of the cam 152, the height of the tuning element 132 It is preferable that the cam 152 is disposed such that the axis of the tuning element 132 and the center of rotation of the cam 152 are aligned to precisely adjust.

(160) disposed between the head and the tuning element support (114) of the cover (111) in the variable filter device (100), the compressed spring (160) The head can exert a force in a direction away from the cover 111.

The profile of the cam 152 may have four points of operation that are spaced at different distances from the center of the cam 152 each time it rotates 90 degrees. In FIG. 3, the tuning element 132 is in contact with the point No.1 of the cam 152, and the tuning element 132 is inserted into the depth as shown in FIG. When the cam 152 rotates 90 degrees in the clockwise direction about the cam rotation axis, the tuning element 132 comes into contact with the second point of the cam, and the tuning element 132 is further inserted. At this time, the compression spring 160 is compressed more than before. Here, when rotated 180 degrees in the clockwise direction, the tuning element 132 comes into contact with the point 4 of the cam so that the insertion depth becomes shallower and the spring becomes more elongated than before.

The point of action of the cam 152 may be four or more. The profile of the cam 152 may have n operating points that are at different distances from the center of the cam 152 each time it rotates 360 / n. By arranging the working points of the cams 152 at slightly smaller angles, a greater number of filter performance can be achieved.

4 is a perspective view schematically showing a variable filter assembly 100 including cams 151, 152, and 153 according to the first embodiment.

The variable filter assembly 100 forms a plurality of cavities 120 inside by coupling the cover 111 and the body 112 and the plurality of cavities 120 are formed by a plurality of cavity walls 123 An input port and an output port 140 penetratingly attached to both longitudinal surfaces of the casing 110 and a resonator 121 formed integrally or attached to the lower surface of the cavity 120. [ A head and a rod, the rod including a plurality of tuning elements (132) penetrating the cover and insertable into the resonator, and a plurality of cams (152) positioned on and in contact with the head And the degree of insertion of the rod is adjusted by the cam 152, thereby changing the center frequency and the bandwidth.

The cavity wall 123 also includes an iris 124 configured as an empty space above the cavity wall 123. The variable filter assembly 100 includes a head and a rod, And a plurality of coupling elements (133) that can be inserted into the iris (124), each head of the coupling element (133) being in contact with a corresponding cam (153).

Further, the input / output coupling amount 131 can be further adjusted, so that the input / output coupling amount can be adjusted as well. That is, the input / output coupling amount can be adjusted by adjusting the distance between the input / output coupling element and the input / output coupling structure 122, and the input / output coupling element 131 can further include the cam 151 in contact with the input / .

The height of the tuning element 132 and the coupling element 133 to be adjusted by the cams 151, 152 and 153 is determined based on four points spaced 90 degrees apart from the center of the cam 152 The axes of the tuning element 132 and the coupling element 133 and the rotation center point of the cams 152 and 153 in order to precisely adjust the height of the tuning element 132 and the coupling element 133. [ It is preferable that the cams 152 and 153 are disposed so as to be positioned on a straight line.

The variable filter assembly 100 further comprises a compressed spring 160 disposed between the head of each tuning element 132 and the coupling element 133 and the cover 111 of the casing 110, The compressed spring 160 can always exert a force in a direction away from the cover 111. [

The movements of the cams 151, 152 and 153 can be integrated and can be simultaneously rotated by one camshaft 154 in order to be integrated. The variable filter assembly 100 thus comprises a camshaft connecting the respective tuning element 132 and the coupling element 133 and the cams 151, 152 and 153 located on the input / output coupling element 131 (154). Accordingly, the cam assembly 150 including the cams 151, 152, and 153 and the camshaft 154 connecting the cams 151, 152, and 153 is formed.

The variable filter device 100 is configured to separate the cam assembly 150 from the casing 110 and to bring the cams 151, 152, 153 into contact with the tuning elements 131, 132, May further include a shaft fixing member (170). The shaft fixing member 170 fixes both ends of the camshaft 154 at a height for positioning the tuning elements 131, 132, 133 at appropriate positions for the frequency tuning.

5 is a cross-sectional view schematically showing a cross-section of a variable filter assembly 100 including cams 151, 152, and 153 according to the first embodiment.

The variable filter assembly 100 may further include a cam driving motor 181 for rotating the cam shaft 154 with external power. When the cam rotation axis 154 is rotated at a desired angle by a filter control unit for controlling the cam driving motor 181, the depth of the tuning elements 131, 132, and 133 is changed by a predetermined amount, .

The variable filter assembly 100 further includes a motor fixing member 182 disposed at one longitudinal end of the casing 110. The motor fixing member 182 is fixed to the cam driving motor 181 Can be positioned so as to be in line with the camshaft 154. The motor fixing member 182 may be integrally joined to the casing 110 without being completely separated from the casing 110. In this case, the cam rotation error that may occur due to the separation of the motor fixing member 182 from the casing 110 can be reduced.

The variable filter assembly 100 may further include a driving coupling 190 for transmitting a driving force of the cam driving motor 181 to the cam shaft 154. The driving coupling 190 may be coupled such that the rotation center of the rotation shaft of the motor 181 and the rotation center of the cam shaft 154 coincide with each other, It can be.

In this case, the driving coupling 190 is connected to the cam driving motor 181, the cam rotating shaft 154 is connected thereto, and all the cams 151, 152 and 153 can be fixed to the cam rotating shaft 154 . As described above, four points can be designed on the outer periphery of the cam to realize four filter performances having different center frequencies and different bandwidths. That is, as shown in FIG. 3, the depths of the elements 131, 132, and 133 are changed by the cam profile each time the all cams are simultaneously rotated by 90 degrees, thereby realizing different filter performances.

Adjusting the insertion depth of all the tuning elements and the coupling elements in this way makes it possible to adjust the center frequency or bandwidth with a very large width.

6 is a schematic cross-sectional view of a cross section of a variable filter device 200 including a lever 240 and a cam 252 according to a second embodiment.

The variable filter device 200 further includes a lever 240 disposed between the head and the cam 252 such that the head abuts the underside of the lever 240 and the cam 252 contacts the lever And the cam 242 is in contact with the upper surface of the cam 240 and the lever 240 further includes a rotation center 242 and a distance between the rotation center 242 and the cam 252 is longer than a distance between the rotation center 242 and the head. The distance may be larger.

And may further include a pedestal 241 for separating the lever 240 from the casing 210. The pedestal 241 is preferably positioned on the left or right side of the casing 210 of the tuning element 232.

The variable filter device 200 further includes a plurality of levers 240 disposed between each of the heads and the cams 252. The heads abut a lower surface of the levers 240, Wherein the lever 240 further includes a rotation center 242 and is positioned so that the distance between the rotation center 242 and the cam 252 is greater than the distance between the rotation center 242 and the head, ) May be greater. The variable filter assembly 200 may further include a cam shaft connecting the cams 252 that are in contact with the upper surfaces of the plurality of levers 240.

When the center frequency is higher than 10 GHz, the depth variation of the tuning element should be very precise. Typical precision machining is 2/100 mm, which may not be satisfactory. In this case, when the lever 240 is used, the machining error of the cam can be reduced. That is, if the distance between the rotation center 242 and the head is 1/5 of the distance between the rotation center 242 and the cam 252, the machining error of the cam may be reduced to 1/5. In order to reduce the error, when the distance between the rotation center 242 and the cam 252 increases, the volume of the entire filter becomes larger, so that the distance between the rotation center 242 and the head is preferably reduced.

7 is a graph illustrating four filter performances implemented using a variable filter assembly according to one embodiment. FIG. 7 shows four different filter performances implemented by the variable filter assembly 100 described above.

(S-parameter, S ₁₁ and S ₂₁ ) obtained using a full-wave electromagnetic analysis program.

The center frequency varied from 2.025 GHz to 2.675 GHz and the bandwidth varied from 50 MHz to 80 MHz. 7 (b), the center frequency is 2.205 GHz and the bandwidth is 50 MHz. In Fig. 7 (c), the center frequency is 2.65 GHz and the bandwidth is 80 MHz , The center frequency is 2.675 GHz and the bandwidth is 50 MHz in Fig. 7 (a). It can be seen that the center frequency and bandwidth can be adjusted over a wide range.

The variation of the center frequency is 27.7% of the center frequency and shows a very wide variable range. Also, in all cases, the return loss does not increase by more than 20 dB in the passband, so it has good variable performance over a very wide frequency range.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention. Accordingly, such modifications or variations are intended to fall within the scope of the appended claims.

100, 200: variable filter device, variable filter assembly
110: casing
120: joint
121: Resonator
123: common wall
124: Iris
131: I / O coupling element
132: tuning element
133: coupling element
141: Input port
150: cam assembly
151, 152, 153: Cam
154: cam shaft
160: spring
181: drive motor
182: motor support member
190: Drive coupling

Claims (17)

1. A variable filter device capable of changing a center frequency and a bandwidth,
The variable filter device includes:
A casing defining a cavity therein by coupling the cover and the body;
A resonator attached or integrally formed on the lower surface of the cavity;
A tuning element including a head and a rod, the rod penetrating the cover and being insertable into the resonator;
A cam located on the head and in contact with the head;
Lt; / RTI >
And the degree of insertion of the rod can be adjusted by the cam.
The method according to claim 1,
Further comprising a lever disposed between the head and the cam,
The head abuts the lower surface of the leverage, the cam abuts the upper surface of the leverage,
Wherein the leverage further includes a rotation center and wherein a distance between the rotation center and the cam is greater than a distance between the rotation center and the head.
The method according to claim 1,
Further comprising a compressed spring disposed between the head and the top of the cover,
Wherein said compressed spring always exerts a force in a direction away from said cover.
The method according to claim 1,
Wherein the profile of the cam has n operating points at different distances from the center of the cam each time it rotates 360 / n.
The method according to claim 1,
And a cam shaft and a shaft fixing member penetrating the center of the cam.
And the camshaft is disposed in contact with the head by the shaft fixing member.
1. A variable filter assembly capable of changing a center frequency and a bandwidth,
The variable filter assembly includes:
A plurality of cavities formed in the interior of the housing by a combination of the cover and the body, the plurality of cavities being divided by a plurality of cavity walls;
An input port and an output port penetratingly attached to both longitudinal sides of the casing;
A resonator attached to each of the cavity lower surfaces;
A plurality of tuning elements including a head and a rod, the rod penetrating the cover and being insertable into the resonator;
A plurality of cams positioned on the respective heads and in contact with the heads;
/ RTI >
Wherein the degree of insertion of the rod is adjustable by the cam.
The method according to claim 6,
Wherein the cavity wall comprises an iris composed of an empty space above the cavity wall,
The variable filter assembly further comprising a plurality of coupling elements that include a head and a rod, the rod penetrating the cover and being insertable into the iris,
Each head of the coupling element abutting a corresponding cam.
8. The method of claim 7,
And a camshaft connecting cams located on each of the tuning elements and the coupling element.
9. The method of claim 8,
Further comprising a shaft fixing member attached to both longitudinal ends of the cover,
Wherein the shaft fixing member positions the cam shaft at a height in contact with the head.
9. The method of claim 8,
And a cam drive motor for rotating the cam shaft with external power.
11. The method of claim 10,
Further comprising a motor fixing member disposed apart from one longitudinal end of the casing,
Wherein the motor fixing member positions the cam driving motor at a height corresponding to the cam axis.
11. The method of claim 10,
And a drive coupling for transmitting the driving force of the cam drive motor between the camshaft and the cam drive motor.
8. The method of claim 7,
Further comprising a compressed spring disposed between the head of each tuning element and the coupling element and the cover of the casing,
Wherein the compressed spring always exerts a force in a direction away from the cover.
The method according to claim 6,
Further comprising a plurality of levers disposed between each of the heads and the cam,
The head abuts the lower surface of the leverage, the cam abuts the upper surface of the leverage,
Wherein the lever further comprises a center of rotation and wherein the distance between the center of rotation and the cam is greater than the distance between the center of rotation and the head.
15. The method of claim 14,
And a camshaft connecting cams in contact with the upper surface of the plurality of levers.
16. The method of claim 15,
And a cam drive motor for rotating the cam shaft with external power.
The method according to claim 6,
Wherein the profile of the cam has n operating points at different distances from the center of the cam each time it rotates 360 / n.

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