KR20190136440A - Filter having combining structure between a resonator and a feeder for improved capacitance - Google Patents

Abstract

According to the present invention, a filter of a resonator structure comprises: a housing with a connector end; at least one cavity formed in the housing; a resonator installed in the cavity and having a receiving groove formed from one side to the other side; and a feeder forming a first facing surface that an inner wall of the receiving groove and an outer surface of a front end part face each other with a gap therebetween since the feeder is integrally formed with a connector connected to the connector end and inserted into the receiving groove. The feeder has a structure in which a second facing surface facing each other with a resonator surface having gap therebetween inside or outside the resonator is formed in addition to the first facing surface.

Description

Filter having combining structure between a resonator and a feeder for improved capacitance}

The present invention relates to a structure of a resonator filter for processing, in particular, bandpass, ultra-high frequency signals.

In the field of high frequency communication technology, a filter having a resonator structure is widely used. The filter of this resonator structure generally has resonators located in two or more cavities properly coupled to each other for microwaves to provide the necessary bandpass characteristics, with each resonator having a top open groove at the top. It consists mainly of metal conductors in the form of cylinders or cubes.

1 shows an equivalent circuit for a filter of a resonator structure mainly used in base stations, repeaters, etc. of a wireless communication network, and each LC loop CRs _i , i = 1, 2, .. 8 corresponds to each resonator. The inductor or capacitor connection between the resonators is determined by a coupling (short or open) method between the resonators.

When a filter having a resonator structure is used for a base station, a repeater, or the like, coupling to an inductance component L _C by shorting between the input terminal TR _i and the first resonator CRs ₁ , as in the equivalent circuit illustrated in FIG. 1. (coupling)

The filter having the configuration of the equivalent circuit described above is provided with an antenna facility for transmitting and receiving microwaves when applied to a base station or a repeater. By the way, the antenna equipment may be provided with a control device for actively controlling the direction of the antenna and the like (tilting of the antenna, etc.), in which case DC power should be supplied to the control device. Therefore, a cable for supplying such DC power must be connected to the antenna installation.

However, in the filter configuration of FIG. 1, since the input terminal is short-circuited with respect to the DC power, it is not possible to supply power to the antenna equipment by sharing a cable connecting to the input terminal of the filter. That is, a separate cable for supplying DC power to the antenna equipment should be provided.

In addition, when the coupling is an inductance component (L _C ) as shown in the filter of FIG. 1, a copper line is shorted to the resonator. At this time, a contact is generated, and the connection contact at this time is the PIMD Deteriorate the characteristics.

It is an object of the present invention to provide a filter capable of supplying DC power to an antenna facility while improving PIMD characteristics.

Another object of the present invention is to provide a filter having a coupling structure between a feeder line and a resonator which can reduce the occupied size of the resonator and the cavity by improving the coupling component.

The object of the present invention is not limited to the object explicitly stated above, and of course includes the purpose of achieving an effect that can be derived from the specific and exemplary description of the present invention.

According to an aspect of the present invention, a filter having a resonator structure includes a housing having a connector end, at least one cavity formed in the housing, and a resonator having an accommodating groove formed at one side and the other side provided in the cavity. And a feeder formed integrally with the connector connected to the connector end and having a front end inserted into the receiving groove, such that the inner wall of the receiving groove and the outer surface of the front end form a first opposing surface facing each other with a gap therebetween. It is configured by. The feeder has a structure in which, in addition to the first facing surface, a second facing surface facing each other with a gap between the resonator surfaces inside or outside the resonator is provided.

In one embodiment according to the present invention, the second opposing surface protrudes in parallel with the accommodation groove from the inner wall of the second accommodation groove formed in the longitudinal direction of the feeder at the tip portion, and from the end wall of the accommodation groove. And is formed by the outer wall of the protruding rod which is formed integrally with the resonator and inserted into the second accommodation groove with the inner wall and the gap therebetween.

In another embodiment according to the present invention, the second opposing surface is integral with the feeder in such a manner that the second opposing surface protrudes in a radial direction at a position on the feeder facing away from the one plane of the resonator by a predetermined gap. It is formed by one side of the flank plate formed.

In another embodiment according to the present invention, the second opposing surface is integrally formed with the feeder in such a manner that the second opposing surface protrudes in the radial direction at a position on the feeder facing away from the outer circumferential surface of the resonator and a predetermined gap away from the outer circumferential surface. It is formed by one side of the flank plate. The plane facing the resonator of the flank is formed with a curved surface having the same curvature as that of the outer circumferential surface.

In another embodiment according to the present invention, the feeder may include the flank plate facing the outer circumferential surface of the resonator while having the second receiving groove facing the outer wall of the protruding rod.

At least one embodiment of the present invention described above, or described in detail in conjunction with the accompanying drawings below, improves PIMD characteristics by coupling a feeder integrally formed with a connector without a contact to a resonator.

In addition, according to various embodiments of the present invention, since the capacitance of the resonator and the coupling of the feeder is increased, it is possible to reduce the size of the space occupied by the resonator and the cavity, thereby miniaturizing the filter. have. In other respects, since the maximum capacity of the capacitance is increased when the space between the resonator and the cavity is not reduced, it is assumed that the component of the filter element is adjusted through means such as a tuning bolt. This means that the range in which the filter having the coupling structure can be applied is expanded.

1 shows an equivalent circuit for a filter of a resonator structure mainly used in base stations, repeaters, etc. of a wireless communication network,
FIG. 2 illustrates a part of an equivalent circuit for a filter in which a coupling between a feeder and a resonator as a capacitance component, according to an embodiment of the present invention,
3 illustrates a portion of a structure in which a filter is coupled as a capacitance component between a resonator and a feeder integrally connected with a connector in a filter according to an embodiment of the present invention.
4 is a cross-sectional view of the coupling structure between the feeder and the resonator according to another embodiment of the present invention,
5 is a perspective view and a cross-sectional view showing a coupling structure between the feeder and the resonator according to another embodiment of the present invention,
6 is a plan view showing a coupling structure between a feeder and a resonator according to another embodiment of the present invention;
7 is a cross-sectional view illustrating a coupling structure to which the embodiment of FIG. 5 or 6 and the embodiment of FIG. 4 are applied together, according to an embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In the description of the embodiments and the accompanying drawings, like reference numerals refer to like elements unless otherwise specified. Of course, for convenience and understanding of the description of the present invention, if necessary, the same components may be added with different numbers.

FIG. 2 shows part of an equivalent circuit for a filter in which coupling between a feeder and a resonator with a capacitance component C _C , according to an embodiment of the invention, and FIG. 3 shows a filter according to the invention. 2 illustrates a portion of a structure coupled as a capacitance component between the feeder FdL1 and the resonator RN1 integrally connected to the connector.

2 and 3 are coupled to the capacitance (C _C ) component, even if a cable for transmitting the DC power and the microwave signal together is connected to the connector end (cTm) provided in the housing 10, the DC component This is not a short circuit. Therefore, branching the copper wire (dcL) from the connector end (cTm) to the antenna installation can supply the power required for the installation.

In addition, as illustrated in FIG. 3, since the coupling by the capacitance component C _C between the feeder FdL1 and the resonator RN1 is an open method that does not form a contact, compared to the coupling of the conventional inductance component. PIMD characteristics can be improved.

Referring to the coupling structure of FIG. 3 in more detail, the cylindrical resonator RN1 installed in the center of the cavity Cav formed in the housing of the filter has a receiving groove R11 in the horizontal direction on the opposite side from the outer peripheral surface of one side. The tip end of the feeder FdL1 formed integrally with the connector is inserted and fixed to the accommodation groove R11. In addition, an inserted material of the feeder FdL1 and an inner surface of the receiving groove R11 of the resonator RN1 are filled with an insulating material such as Teflon PTFE.

When the feeder FdL1 and the resonator RN1 are mutually coupled in the same manner as the structure illustrated in FIG. 3, the capacitance components are coupled by both conductors with a gap therebetween. At this time, the capacitance capacity is determined by the width of the surface facing each other between the inserted portion of the feeder FdL1 and the inner wall of the receiving groove R11 of the resonator RN1, its gap, and the dielectric constant of the material filled in the gap.

As illustrated in FIGS. 2 and 3, the bandpass characteristics of the filter are different from those of the conventional inductance components illustrated in FIG. 1 due to the coupling of the capacitance components. In order to do this, you adjust the values of the L or C components in the other components of the filter. For this adjustment, as illustrated in FIG. 3B (sectional view when the center of the resonator is cut in the vertical plane), the tuning bolt TB is placed in the adjustment groove TH formed at the upper end of the resonator RN1. Adjusting the depth of insertion is included.

As illustrated in FIG. 3, when coupling the feeder FdL1 and the resonator RN1 in an open structure, the capacitance capacity required for the characteristics of the filter may not be sufficient. Therefore, in another embodiment according to the present invention, a structure having a larger capacitance can be coupled between the feeder and the resonator. Figure 4 shows a cross section of the coupling structure between the feeder and the resonator according to an embodiment of the present invention for increasing capacitance capacity.

The coupling structure according to the embodiment of FIG. 4 has a cylindrical shape integral with the resonator which protrudes in parallel with the receiving outer groove in a longitudinal end wall of the receiving outer groove R21 formed on the opposite side from the outer peripheral surface of one side of the resonator RN2. Protruding rod R22 is formed, and in the case of feeder FdL2, the receiving inner groove F21 capable of accommodating the protruding rod R22 at the distal end inserted into the receiving outer groove R21 has a longitudinal direction of the feeder. It is formed. Of course, the insulating material is also filled in the gap between the receiving inner groove (F21) and the opposing surface of the protruding rod (R22).

In the coupling structure illustrated in FIG. 4, the capacitance of the capacitance increases by approximately corresponding to the width of the surface facing each other between the outer circumferential surface of the protruding rod R22 and the inner wall of the receiving inner groove F21. Thus, assuming the same dimensions as the resonators and cavities coupled to the structure illustrated in FIG. 3, the embodiment of FIG. 4 has a larger capacitance than that of FIG. 3, thus requiring a filter. Capacitance that satisfies the filter characteristic can be provided.

In other respects, if the filter requires the same capacitance as in the embodiment of FIG. 3, the embodiment of FIG. 4 may be implemented as a resonator having a smaller size than that of the embodiment of FIG. 3. Therefore, when a filter having the same characteristic is assumed, a resonator and a cavity having a smaller size are possible than those of the embodiment of FIG. 3, so that the overall size of the filter can be made smaller.

In another embodiment according to the present invention, a larger capacitance can be secured by securing a conductor surface facing the outer circumferential surface of the resonator. 5 shows a coupling structure of a resonator and a feeder according to the present embodiment.

In the coupling structure according to the embodiment of Fig. 5, compared with the embodiment of Fig. 3, the feeder FdL3 is a disk-shaped flank plate protruding in the radial direction with a predetermined gap with the outer circumferential surface of the resonator RN3. (F31) is integrally provided, and the said resonator RN3 has the cylindrical shape of the reflection angle-semi-circle shape (or polyhedron) which has the outer surface RN31 parallel to one side plane of the flank plate F31. Compared to the embodiment of FIG. 3, the flank plate F31 of the feeder FdL3 has an area of the opposite surface by forming an opposing surface with a predetermined gap between the outer surface RN31 of the resonator RN3. This will add more capacitance.

In another embodiment according to the present invention, the resonator may have a cylindrical shape as in the embodiment of FIG. 3, and the capacitance of the capacitance may be increased as compared with the coupling structure of the embodiment of FIG. 6 is a plan view showing a coupling structure of a resonator and a feeder FdL4 to which a flank plate F41 having a shape according to the present embodiment is applied.

In the planar flank plate F41 according to the embodiment of FIG. 6, the surface facing the resonator is composed of a curved surface having the same curvature as the outer circumferential surface curvature of the resonator, so that the gap with the circumferential surface of the resonator is constant over the entire opposite surface. Done.

The coupling structures of the above-described embodiments have increased the capacitance of the capacitance by forming a double surface facing each other with the feeder inside the resonator or additionally forming a surface facing each other with the feeder at the side of the resonator. The bonding structure may be applied together.

FIG. 7 is a cross-sectional view illustrating a coupling structure of a resonator and a feeder according to an embodiment, in which the resonator RN5 includes a receiving outer groove R51 and a protruding rod R52 as in the embodiment of FIG. It has a flat surface as illustrated in Fig. 5, and the feeder FdL5 has a receiving inner groove F51 and a flank plate F52 as in the embodiment of Figs. Through the facets and through the opposing facets on the resonator side, both capacitances can be ensured.

On the other hand, the flank plate F52 in the embodiment of FIG. 7 has a surface facing the outer circumferential surface when the resonator RN5 has a cylindrical shape as in the embodiment of FIG. 6.

Table 1 below shows the results of simulating the filter characteristics of the coupling structure of some of the above-described embodiments, and shows the dimensions of the cavity and the resonator, and thus the delay time characteristics of the signals.

3 embodiment 4 embodiment 5 embodiment Acceptance groove diameter: 4.0 [mm]
Tip diameter: 3.3 [mm] Receiving groove diameter: 5.6
Tip diameter: 5.2
Protrusion bar diameter: 2.4 Accommodation groove diameter: 4.0
Tip diameter: 3.3
Flange Plate Diameter: 11.0 Cavity Size [mm]
(Diameter x height) 37 x 50 32 x 50 33 x 50 Resonator size [mm]
(Diameter x height) 22 x 48.5 19 x 48.5 20 x 48.5 Delay time [ns] 2.40 2.41 2.39

The delay time in Table 1 is the time taken to return when the microwave of the center frequency of the passband of the filter is incident through the connector in the form of a loop with respect to the resonator of the coupling structure (i.e., , Delay of the S11 parameter). If these times are the same, the characteristics of the filter can be regarded as the same.

As shown in Table 1, a delay time substantially equal to 2.4 [ns], which is the delay time obtained for the embodiment of FIG. 3 in which an accommodating groove was formed in the resonator and a single opposing face with the feeder in the accommodating groove, was obtained. The size (ie volume) of the resonator (and cavity) in the coupling structure of the embodiment of FIGS. 4 and 5 is reduced by approximately 20-25% compared to the embodiment of FIG. 3.

That is, when the embodiment of FIG. 4, 5, or 6 is applied, the same filter characteristic may be obtained as a filter that is more compact than the filter according to the embodiment of FIG. 3. Naturally, the filter according to the embodiment of Fig. 7 makes it possible to further miniaturize the filter of the same characteristic.

The various embodiments described so far with respect to the present invention and the structure and operation described in the embodiments may be selectively combined with each other in various ways, unless they are incompatible with each other.

Or more, the above-described embodiments of the present invention are disclosed for the purpose of illustration, and those skilled in the art, within the technical spirit and the technical scope of the present invention disclosed in the appended claims below, further various other embodiments, Modifications, substitutions or additions may be made.

Cav: Cavity cTm: Connector End
FdL1, FdL2, FdL3, FdL4, FdL5: Feeder F21, F51: Inner groove
F31, F41: Flank plate RN1, RN2, RN3, RN4, RN5: Resonator
R11: accommodation groove R21, R51: accommodation outer groove
R22, R52: protrusion bar TB: tuning bolt
TH: adjusting groove 10: housing

Claims (5)

In the filter of the resonator structure,
A housing with a connector end,
At least one cavity formed in the housing,
A resonator provided in the cavity and having a receiving groove formed from one side to the other side;
And a feeder formed integrally with a connector connected to the connector end, and having a front end inserted into the receiving groove, the inner wall of the receiving groove and the outer surface of the leading end forming a first facing surface facing each other with a gap therebetween. Composed,
The feeder has a structure in which, in addition to the first facing surface, a second facing surface is formed between the resonator and facing each other with a gap therebetween. The method of claim 1,
The second opposing surface is integrally formed with the resonator in a form protruding in parallel with the receiving groove from the inner wall of the second receiving groove formed in the longitudinal direction of the feeder at the distal end portion, and from the end wall of the receiving groove. The filter formed by the outer wall of the protrusion rod inserted in the 2nd accommodating groove leaving gap with the inner wall. The method of claim 1,
The second facing surface is formed by one side surface of the resonator and a flank plate integrally formed with the feeder so as to protrude in the radial direction at a position on the feeder facing away from the one side plane by a predetermined gap. Filter. The method of claim 1,
The second facing surface is formed by one side of the flank plate integrally formed with the feeder in a form projecting in the radial direction from the position on the feeder facing the outer peripheral surface of the resonator and a predetermined gap away from the outer peripheral surface, The surface facing the resonator of the flank plate is formed of a curved surface of the same curvature as the curvature of the outer peripheral surface. The method of claim 1,
The feeder further includes a structure for forming a third facing surface facing each other with a gap between the outer circumferential surface of the resonator, in addition to the first facing surface and the second facing surface,
The second opposing surface is integrally formed with the resonator in a form protruding in parallel with the receiving groove from the inner wall of the second receiving groove formed in the longitudinal direction of the feeder at the distal end portion, and from the end wall of the receiving groove. Formed by the outer wall of the protruding rod inserted in the second accommodation groove with a gap between the inner wall thereof,
The third facing surface is formed by one side surface and the outer peripheral surface of the flank plate integrally formed with the feeder in a form projecting in the radial direction at a position on the feeder facing a predetermined gap with the outer peripheral surface.

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