JPH0685505U - Dielectric resonator filter - Google Patents

Abstract

(57) [Summary] [Object] To provide a dielectric resonator filter capable of preventing rotation of an open-ended coupling loop. [Structure] The dielectric resonator 2 is arranged in the metal case 1,
I / O coaxial connector 3 penetrating metal case 1
And the open end type coupling loop 4 connected to the center conductor 3a of the input / output coaxial connector 3 is provided in the metal case 1 in a direction parallel to the electric field. A pin-shaped insulator 5 for holding the orientation of the open-ended coupling loop 4 is provided in the metal case 1.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a dielectric resonator filter used for selecting a desired wave and blocking an unnecessary wave in a microwave communication device, a radar device and the like.

[0002]

[Prior art]

 The structure of a conventional dielectric resonator filter is shown in FIG. The dielectric resonator filter has a rectangular parallelepiped metal case 1, and a dielectric resonator 2 is arranged in the metal case 1. Further, the metal case 1 is provided with an input / output coaxial connector 3 penetrating the metal case 1. In the metal case 1, an open end type coupling loop 4 connected to the central conductor 3 a of the input / output coaxial connector 3 is provided in a direction parallel to the electric field.

In such a dielectric resonator filter, a magnetic field generated from the open end 4 a of the coupling loop 4 at a wavelength of about ¼ is most suitable for coupling with the dielectric resonator 2. An open end coupling loop 4 is used.

In the conventional dielectric resonator filter of this type, the open end type coupling loop 4 is fixed to the central conductor 3a of the input / output coaxial connector 3 only by soldering or the like.

[0005]

[Problems to be solved by the device]

 However, the center conductor 3a of the input / output coaxial connector 3 is usually only adhered or press-fitted so as not to rotate, so that the center conductor 3a is not bonded to the above-described center conductor 3a due to soldering or changes in environmental conditions. Fixing may become invalid, and when connecting the connector, the center conductor 3a rotates, and the degree of coupling between the open-ended coupling loop 4 and the dielectric resonator 2 changes, causing deterioration of electrical characteristics. There was a point.

Further, in the conventional structure, in order to adjust the degree of coupling between the open-end type coupling loop 4 and the dielectric resonator 2, the metal case 1 needs to be disassembled, and the electrical characteristics of the dielectric resonator filter are reduced. There is a problem that it takes a lot of time and effort to optimize the characteristics.

An object of the present invention is to provide a dielectric resonator filter capable of preventing rotation of an open-ended coupling loop.

Another object of the present invention is to provide a dielectric resonator filter capable of preventing rotation of an open-ended coupling loop and easily optimizing electrical characteristics.

[0009]

[Means for Solving the Problems]

 The structure of the present invention which achieves the above object will be described below.

According to a first aspect of the present invention, a dielectric resonator is arranged in a metal case, an input / output coaxial connector is provided through the metal case so as to penetrate the metal case, and the input / output coaxial connector is provided. A dielectric resonator filter having an open-ended coupling loop connected to the center conductor of the inductor in the metal case in a direction parallel to an electric field, wherein the open-ended coupling loop is oriented in the metal case. It is characterized in that an insulator for holding is provided.

According to a second aspect of the present invention, a dielectric resonator is arranged in a metal case, an input / output coaxial connector is provided through the metal case so as to penetrate the metal case, and the input / output coaxial connector is provided. A dielectric resonator filter having an open-ended coupling loop connected to the center conductor of the inductor in the metal case in a direction parallel to an electric field, wherein the open-ended coupling loop is oriented in the metal case. Is provided, and the metal case is provided with a metal stub that penetrates the metal case by a screw connection and that can change a distance from the open end type connection loop.

[0012]

[Action]

 As described in claim 1, when the insulator for holding the orientation of the open end type coupling loop is provided in the metal case, the rotation of the open end type coupling loop can be prevented. Therefore, it is possible to prevent the open-end type coupling loop from rotating and changing the degree of coupling between the open-end type coupling loop and the dielectric resonator to deteriorate the electrical characteristics.

According to a second aspect of the present invention, an insulator for holding the orientation of the open end type coupling loop is provided in the metal case, and the metal case is threadedly penetrated into the insulator to open the end type coupling loop. If a metal stub whose distance from the loop is variable is provided, the rotation of the open end type coupling loop can be prevented, and at the same time, the metal stub penetrating the metal case with a screw connection can be adjusted to form the open end type coupling loop. By changing the distance, the electric characteristics of the dielectric resonator filter can be easily optimized in a short time without disassembling the metal case.

[0014]

【Example】

 1 and 2 show an embodiment of a dielectric resonator filter according to the present invention. The components corresponding to those in FIG. 4 described above are designated by the same reference numerals.

In the dielectric resonator filter of the present embodiment, the open-end type coupling loop 4 is fixed so as not to rotate by a pin-shaped insulator 5 penetrating it in a direction parallel to the electric field. The insulator 5 is supported by penetrating both ends thereof into the metal case 1. One end of the pin-shaped insulator 5 is passed through the center hole 7 of the metal stub 6 and supported by the metal case 1 via the metal stub 6. The metal stub 6 is threadedly connected to the metal case 1 at a position facing the open end 4a of the open end type coupling loop 4. A lock nut 8 is screwed onto the outer periphery of the metal stub 6 protruding from the metal case 1.

In such a dielectric resonator filter, since the insulator 5 for holding the orientation of the open end type coupling loop 4 is provided in the metal case 1, the insulator 5 prevents the open end type coupling loop 4 from moving. It can prevent rotation. Therefore, it is necessary to prevent the open end type coupling loop 4 from rotating for some reason and changing the degree of coupling between the open end type coupling loop 4 and the dielectric resonator 2 to cause deterioration of electrical characteristics. You can

In particular, when the pin-shaped insulator 5 as shown in the figure is used as the rotation preventing means of the open end type coupling loop 4 and the open end type coupling loop 4 is supported in the direction as shown in the figure, the inside of the metal case 1 is It is preferable because the increase of loss due to the insertion of the insulator 5 can be minimized.

Further, by adjusting the metal stub 6 to change the distance from the open-end type coupling loop 4, it is possible to optimize the electrical characteristics of the dielectric resonator filter without disassembling the metal case 1. Can be easily done in time.

FIG. 3 shows how the degree of coupling between the open end type coupling loop 4 and the dielectric resonator 2 changes when the distance between the metal stub 6 and the open end type coupling loop 4 is changed. It is a thing. The characteristic curve of the dielectric resonator filter varies depending on the length from the open end 4a of the open-ended coupling loop 4 to the position closest to the dielectric resonator 2. Curve A is a characteristic curve when the insertion length of the metal stub 6 is changed when the length is about 1/4 wavelength, and curve B is a metal stub when the length is shorter than about 1/4 wavelength. 6 is a characteristic curve when the insertion length of 6 is changed. This is because the magnetic field coupled to the dielectric resonator 2 is most strongly generated at a quarter wavelength from the open end 4a of the open end type coupling loop 4, and the open end type coupling loop 4 is opened. By bringing the metal stub 6 close to the end 4a, the capacitive property is increased, and the electrical length is lengthened to move the magnetic field generation position to change the coupling degree.

The rotation preventing means of the open end type coupling loop 4 is not limited to the pin-shaped insulator 5 as shown in the figure, but an insulator having another shape may be used to form the dielectric resonator 2 in the metal case 1. The open end type coupling loop 4 can be fixed so as not to rotate by supporting the open end type coupling loop 4 on the same side as the supporting surface.

Further, in the above-mentioned embodiment, the metal stub 6 is provided on the open end 4a side of the open end type coupling loop 4, but the same effect can be obtained by providing it on the opposite side, and both ends are connected to each other. If it is provided at the position, the adjustment range can be expanded.

[0022]

[Effect of device]

 As described above, according to the dielectric resonator filter of the present invention, the following excellent effects can be obtained.

In the dielectric resonator filter according to the first aspect of the present invention, since the insulator that holds the orientation of the open end type coupling loop is provided in the metal case, the rotation of the open end type coupling loop can be prevented. . Therefore, it is possible to prevent the degree of coupling between the open-end type coupling loop and the dielectric resonator from changing due to the rotation of the open-end type coupling loop, resulting in deterioration of electrical characteristics.

According to another aspect of the dielectric resonator filter of the present invention, an insulator that holds the orientation of the open-ended coupling loop is provided in the metal case, and the metal case is threadedly penetrated into the insulator. Since a metal stub that can change the distance to the open end type coupling loop is provided, it is possible to prevent rotation of the open end type coupling loop and adjust the metal stub to change the distance to the open end type coupling loop. Even if the metal case is not disassembled, the electrical characteristics of the dielectric resonator filter can be easily optimized in a short time.

[Brief description of drawings]

FIG. 1 is a plan view of a main part of a dielectric resonator filter according to an embodiment of the present invention with a lid removed.

FIG. 2 is a sectional view taken along line XX of FIG.

FIG. 3 is a characteristic diagram showing a change in coupling degree when the insertion length of a metal stub is changed in this embodiment.

FIG. 4 is a perspective view of a main part of a conventional dielectric resonator filter with a lid removed.

[Explanation of symbols]

 1 Metal Case 2 Dielectric Resonator 3 Input / Output Coaxial Connector 3a Center Conductor 4 Open End Type Coupling Loop 4a Open End 5 Pin Insulator 6 Metal Stub 7 Center Hole 8 Lock Nut

Claims (2)

[Scope of utility model registration request] 1. A dielectric resonator is arranged in a metal case,
An input / output coaxial connector is provided through the metal case, and an open-ended coupling loop connected to the center conductor of the input / output coaxial connector is provided in the metal case in a direction parallel to the electric field. In the dielectric resonator filter described above, an insulator that holds the orientation of the open-ended coupling loop is provided in the metal case. 2. A dielectric resonator is arranged in a metal case,
An input / output coaxial connector is provided through the metal case, and an open-ended coupling loop connected to the center conductor of the input / output coaxial connector is provided in the metal case in a direction parallel to the electric field. In the dielectric resonator filter, an insulator that holds the orientation of the open-ended coupling loop is provided in the metal case, and the open-ended coupling loop penetrates the metal case by screw coupling. A dielectric resonator filter, wherein a metal stub whose distance from and is variable is provided.