JP4819857B2 - Dielectric resonator and method for controlling dielectric resonator - Google Patents

Description

  The present invention relates to a dielectric resonator and a method for controlling the dielectric resonator.

  In recent years, electronic devices typified by portable information terminals and communication terminals have been remarkably improved in function and size. A resonator filter is incorporated in these portable information terminals and communication terminals, and with the downsizing of the above-described portable information terminal, the resonator filter is also required to be downsized. As a result, the dielectric resonator Has come to be used.

  As the dielectric resonator, for example, as described in Patent Document 1, a dielectric resonator element is disposed in a cavity resonator, and the cavity resonator is directed toward the dielectric resonator element. A multimode dielectric resonator corresponding to a plurality of frequencies is disclosed by providing a metal screw and performing a resonance coupling mode. However, such a dielectric resonator has a problem that a transmission loss of an electric signal used for resonance becomes large because a metal screw exists in the resonator.

In order to solve the above problem, Patent Document 2 discloses a multi-mode dielectric resonator corresponding to a plurality of frequencies by making a resonant coupling mode by opening a cylindrical hole in a dielectric resonator element. Yes. However, since these dielectric resonators involve processing such as cutting, the manufacturing cost increases, and a sufficient resonance coupling mode cannot be performed, so that a multimode resonance corresponding to a plurality of frequencies sufficient for practical use is possible. The vessel could not be realized.
JP-A-57-194603 JP-A-62-204601

  SUMMARY OF THE INVENTION An object of the present invention is to provide a dielectric resonator having a simple configuration corresponding to a multimode without transmission loss of an electric signal, and a method for manufacturing the dielectric resonator.

In order to achieve the above object, the present invention provides:
A cylindrical or polygonal outer conductor;
A dielectric resonant element disposed substantially at the center of the outer conductor;
An electric signal input unit and an electric signal output unit,
The present invention relates to a dielectric resonator characterized in that a notch is formed in a part of the dielectric resonator element at a position and a size such that a coupling coefficient for a plurality of introduced electric signals has a peak.

The present invention also provides:
A method of manufacturing a dielectric resonator comprising a cylindrical or polygonal outer conductor and a dielectric resonator element disposed substantially at the center of the outer conductor,
The present invention relates to a method for manufacturing a dielectric resonator, characterized in that a notch is formed in a part of the dielectric resonator element at a position and size such that a coupling coefficient with respect to a plurality of introduced electrical signals has a peak.

  According to the present invention, a notch is formed in the dielectric resonant element in contrast to the conventional basic configuration in which a cylindrical or polygonal dielectric resonant element is provided in the outer conductor. Further, the positions and sizes of the notches are formed such that the coupling modes in a plurality of electrical signals introduced into the dielectric resonator have peaks. Therefore, as in the prior art, when a coupling mode (resonance state) is controlled, a metal screw or the like is not used, so that there is no transmission loss of an electric signal to be used for resonance, and further, a dielectric resonator element A dielectric resonator in which the above-described coupling mode (resonance state) is controlled to be in an optimum state can be easily obtained without using complicated processes such as processing.

  Note that the reason why the coupling mode (resonance state) of the dielectric resonator changes as described above is thought to be because the inductance and / or coupling capacitance with respect to the electric signal introduced into the dielectric resonator changes. .

  In one aspect of the present invention, the notch is formed by vertically grinding the dielectric resonator element along a height direction, and the dielectric resonator element is perpendicular to the height direction due to the notch. It can be formed to have a simple cross section. As a result, the peak state of the coupling mode (resonance state) of the dielectric resonator can be realized more easily.

  Further, in another aspect of the present invention, the notch is at least two notches, and the two notches are formed on opposite surfaces of the dielectric resonant element, and the dielectric resonant element includes: It is possible to have two cross sections perpendicular to the height direction due to the two notches and parallel to each other. By forming such two notches, the peak state of the coupling mode (resonance state) of the dielectric resonator can be realized more easily.

  As described above, according to the present invention, it is possible to provide a dielectric resonator having a simple configuration corresponding to a multimode without a transmission loss of an electric signal, and a manufacturing method thereof.

  Hereinafter, embodiments of the present invention will be described.

  FIG. 1 is a plan view of a dielectric resonator according to this embodiment, and FIG. 2 is a side view of the dielectric resonator shown in FIG. FIG. 3 is an equivalent circuit of the dielectric resonator shown in FIGS.

  As shown in FIGS. 1 and 2, the dielectric resonator 10 in the present embodiment includes a cylindrical outer conductor 11, a columnar dielectric resonator element 12 disposed at a substantially central portion O of the outer conductor 11, and An electrical signal input unit 14 and an electrical signal output unit 15 are arranged on the circumferential surface of the outer conductor 11 so as to form an angle of 90 degrees with each other. The dielectric resonant element 12 is disposed on a support base (not shown) made of, for example, alumina. Further, since the dielectric resonant element 12 is disposed at the substantially central portion O of the outer conductor 11, the substantially central portion O is also common with the center of the dielectric resonant element 12.

  Further, the dielectric resonator element 12 is arranged along the height direction so as not to face the electric signal input unit 14 and the electric signal output unit 15 provided in the dielectric resonator 10. A pair of notches 12A and 12B formed by vertical grinding is formed. As a result, the dielectric resonator element 12 has two cross sections that are perpendicular to the height direction due to the two notches 12A and 12B and are parallel to each other.

  3, C1 is a capacitive coupling circuit that capacitively couples the electrical signal input unit 14 and the resonant circuit of the dielectric resonator 10, and C5 is a resonant circuit of the electrical signal output unit 15 and the dielectric resonator 10. Is a capacitive coupling circuit. Further, C2 and L1, and C4 and L2 are a capacitive coupling circuit and an inductance constituting a resonance circuit of the dielectric resonator 10, respectively. Further, C3 is an intermittent coupling capacitance formed by the notches 12A and 12B.

  The capacitive coupling circuits C1 and C5 in FIG. 3 vary depending on the materials constituting the electric signal input unit 14 and the electric signal output unit 15 and their sizes. Further, the capacitive coupling circuits C2 and C4 and the inductances L1 and L2 in FIG. 3 vary depending on the materials constituting the notches 12A and 12B and the external conductor 11.

  In the present embodiment, in particular, by providing the notches 12A and 12B, the values of the capacitive coupling circuits C2 and C4 and C3 change, and the values of the inductances L1 and L2 change, so that the resonance state (coupling mode) Is considered to change.

  FIG. 4 shows the size (depth H) of the notches 12A and 12B of the dielectric resonator 10 according to the present embodiment and the coupling between the two EH modes (EH1 and EH2) introduced into the dielectric resonator 10. It is the figure which investigated the correlation with a coefficient. As can be seen from FIG. 4, the coupling coefficient shows a peak when the depth H of the notches 12A and 12B, that is, the grinding amount is 1.5-3 mm. That is, in the dielectric resonator 10 shown in FIG. 1, the two EH modes introduced into the dielectric resonator 10 are set by setting the depth H of the notches 12A and 12B in the range of 1.5-3 mm. It can be seen that the coupling coefficient of (EH1 and EH2) is approximately maximized, and a predetermined resonance state is realized.

  As a premise for obtaining the graph shown in FIG. 4, the diameter of the dielectric resonator element 12 was 37 mm.

A. Modification 1
In the first embodiment, a description will be given of a case where the notch 12A has a groove shape in the axial direction of the dielectric resonant element 12 (Modification 1). FIG. 5 is a plan view showing the dielectric resonant element 12 according to the first modification. In the first modification, the notch 12 </ b> A is a substantially rectangular parallelepiped groove having a bottom surface and two side surfaces, and is arranged in the axial direction of the dielectric resonant element 12. FIG. 6 is a graph showing a correspondence relationship between the frequency and the attenuation state of the electric signal when the height H of the notch 12A of the dielectric resonator 20 is changed in the first modification. In each of the graphs G11 to G17, the width D is 5 mm, and the height H is 2.5, 5.0, 7.5, 10.0, 12.5, 15.0, 17.5 mm. FIG. 7 is a graph showing the relationship between the height H, the resonance frequency fk, and the coupling coefficient k. Increasing the height H increases the resonance frequency fk, while the coupling coefficient k has a peak (saturates).

B. Modification 2
In the first embodiment, a description will be given of a case where the notch 12A has a groove shape in the radial direction of the dielectric resonator element 12 (Modification 2). FIG. 8 is a plan view showing the dielectric resonant element 12 according to the third modification. In the second modification, the notch 12 </ b> A is a substantially rectangular parallelepiped groove having a bottom surface and two side surfaces, and is arranged in the radial direction of the dielectric resonant element 12. FIG. 9 is a graph showing the correspondence between the frequency and the attenuation state of the electric signal when the height H of the notch 12A of the dielectric resonator 20 is changed in the second modification. In each of the graphs G21 to G25, the thickness T is 2 mm, and the height H is 2.5, 5.0, 7.5, 10.0, 12.5 mm. FIG. 10 is a graph showing the relationship between the height H, the resonance frequency fk, and the coupling coefficient k. Increasing the height H increases the resonance frequency fk, while the coupling coefficient k has a peak (saturates).

C. Modification 3
In the first embodiment, the notch 12A has a groove shape (cylindrical shape) on the side surface of the dielectric resonant element 12 and a radial groove shape toward the center of the dielectric resonant element 12 (Modification 3). ) FIG. 11 is a top view and a side view showing a dielectric resonant element 12 according to Modification 3. In the third modification, the notch 12 </ b> A is a cylindrical groove having a circular side surface, and is arranged in the radial direction toward the center of the dielectric resonator element 12. FIG. 12 is a graph showing a correspondence relationship between the frequency and the attenuation state of the electric signal when the height H and the diameter D of the notch 12A of the dielectric resonator 20 are changed in the third modification. In each of the graphs G31 to G37, the diameter D is 2 mm, and the height H is 2.5, 5.0, 7.5, 10.0, 12.5 mm. FIG. 13 is a graph showing the relationship between the height H, the resonance frequency fk, and the coupling coefficient k. Increasing the height H increases the resonance frequency fk, while the coupling coefficient k has a peak (saturates).

D. Modification 4
In the first embodiment, a case where the shape of the dielectric resonant element 12 is a regular octagon (Modification 8) will be described. FIG. 14 is a top view showing a dielectric resonator element 12 according to Modification 8. As shown in FIG. In the modified example 8, the dielectric resonator element 12 is a regular octagonal columnar shape, and a notch 12A is disposed along one side thereof. FIG. 15 is a graph showing a correspondence relationship between the frequency and the attenuation state of the electrical signal when the height H of the notch 12A is changed in the fourth modification. In each of the graphs G41 to G47, the height H is 3, 5, 7, 9, 11, 13, 15 mm. FIG. 16 is a graph showing the relationship between the height H, the resonance frequency fk, and the coupling coefficient k. Increasing the height H increases the resonance frequency fk, while the coupling coefficient k has a peak (saturates).

(Causes of peaks)
The reason why the coupling coefficient k has a peak will be described. 17 and 18 are schematic views showing electric field distributions in the dielectric resonator 10 at H = 2.5 and 5.0, respectively. FIGS. 17 and 18 (1) and 18 (2) respectively show electric field distributions in two modes in the radial direction of the dielectric resonant element 12. It can be seen that the electric field distribution, that is, the resonance mode is changed by increasing the height H (grinding amount). This change is considered to cause the peak of the coupling coefficient k.

  The present invention has been described in detail with specific examples. However, the present invention is not limited to the above contents, and various modifications and changes can be made without departing from the scope of the present invention.

  As described above, various shapes can be applied to the dielectric resonator and the notch. As shown in the above embodiment, a cylindrical resonator and a regular octagonal prism can be used as the dielectric resonator. In addition to these, an intermediate shape such as an elliptical column or a quadrangular column can be used. In addition to columnar shapes, plate shapes can also be used. As shown in the above embodiment, various shapes such as a flat plate shape and a groove shape can be used as the notch.

  In the above specific example, the pair of notches 12A and 12B are formed in the dielectric resonator element 12, but the present invention can also be achieved by forming at least one notch, for example, only one of the notches 12A and 12B. The effect of this can be obtained. However, in accordance with the above specific example, by providing the notches 12A and 12B at the opposing positions of the dielectric resonator element 12, the coupling coefficient of the two EH modes in the dielectric resonator 10 can be controlled more easily, and the peak You will be able to get the value.

  Of course, three or more notches can be provided, and the shape of the notches can be various shapes.

  The above specific examples are based on numerous simulations and experimental results based on the simulations, and are specific examples of how to adjust the position and size of the notches in the dielectric resonator element. The guideline differs depending on the configuration of the dielectric resonator. For example, depending on the positional relationship between the electrical signal input unit and the electrical signal output unit of the dielectric resonator, the positional relationship between the electrical signal input unit and the electrical signal output unit, the depth of the notch that becomes the peak of the coupling coefficient differs, and the coupling coefficient The relationship between the depth of the notch and the depth of the notch is also different.

  It should be noted that the coupling coefficient in the dielectric resonator is basically the same as that in the prior art based on the selection of the size (height and diameter) of the dielectric resonant element with respect to the outer conductor.

  In the above specific example, only the case where the dielectric resonator is formed of a cylindrical outer conductor has been described. However, the same effect can be obtained when the dielectric resonator is formed of a polygonal outer conductor.

  Further, in the present invention, it is not excluded to provide a metal screw or a resin screw on the external conductor toward the dielectric resonance element as in the past, as long as the operation effect by the notch of the present invention is not hindered. Absent.

It is a top view of the dielectric resonator in embodiment of this invention. It is a side view of the dielectric resonator shown in FIG. 3 is an equivalent circuit of the dielectric resonator shown in FIGS. It is the figure which investigated the correlation with the coupling coefficient of two EH modes (EH1 and EH2) introduce | transduced in the dielectric resonator in the dielectric resonator in embodiment of this invention. 10 is a plan view of a dielectric resonator according to Modification 1. FIG. 10 is a graph showing an attenuation state of an electric signal of a dielectric resonator according to Modification 1. 10 is a graph showing notch depth dependency of a resonance frequency and a coupling coefficient of a dielectric resonator according to Modification 1. 10 is a plan view of a dielectric resonator according to Modification 2. FIG. 10 is a graph showing an attenuation state of an electric signal of a dielectric resonator according to Modification 2. 10 is a graph showing notch depth dependency of a resonance frequency and a coupling coefficient of a dielectric resonator according to Modification 2. 10 is a plan view of a dielectric resonator according to Modification 3. FIG. 10 is a graph showing an attenuation state of an electric signal of a dielectric resonator according to Modification 3. 12 is a graph showing notch depth dependence of the resonance frequency and coupling coefficient of a dielectric resonator according to Modification 3. 10 is a plan view of a dielectric resonator according to Modification 4. FIG. 10 is a graph showing an attenuation state of an electric signal of a dielectric resonator according to Modification 4. It is a graph which shows the notch depth dependence of the resonant frequency and coupling coefficient of the dielectric resonator in the modification 4. It is a schematic diagram showing the electric field distribution in a dielectric resonator. It is a schematic diagram showing the electric field distribution in a dielectric resonator.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Dielectric resonator 11 External conductor 12 Dielectric resonant element 12A, 12B Notch 14 Electric signal input part 15 Electric signal output part

Claims (8)

A cylindrical or polygonal outer conductor;
A dielectric resonant element disposed substantially at the center of the outer conductor;
An electric signal input unit and an electric signal output unit,
A dielectric resonator, wherein a notch is formed in a part of the dielectric resonator element at a position and a size such that a coupling coefficient for a plurality of introduced electrical signals has a peak.   2. The dielectric resonator according to claim 1, wherein the dielectric resonator element has a columnar shape or a plate shape having a circular, elliptical, or polygonal cross section.   The notch is formed by vertically grinding the dielectric resonant element along a height direction, and the dielectric resonant element has a vertical cross section in the height direction caused by the notch. The dielectric resonator according to claim 1 or 2.   The notches are at least two notches, and the two notches are formed on the opposing surfaces of the dielectric resonator element, and the dielectric resonator element has a height direction caused by the two notches. The dielectric resonator according to claim 3, wherein the dielectric resonator has two cross sections perpendicular to each other and parallel to each other. A method of manufacturing a dielectric resonator comprising a cylindrical or polygonal outer conductor and a dielectric resonator element disposed substantially at the center of the outer conductor,
A method of manufacturing a dielectric resonator, wherein a notch is formed in a part of the dielectric resonator element at a position and size such that a coupling coefficient with respect to a plurality of introduced electrical signals has a peak.   6. The method of manufacturing a dielectric resonator according to claim 5, wherein the dielectric resonator element is a columnar shape or a plate shape having a circular, elliptical, or polygonal cross section.   The notch is formed by grinding the dielectric resonant element vertically along the height direction so that the dielectric resonant element has a vertical cross section in the height direction caused by the notch. The method for manufacturing a dielectric resonator according to claim 5 or 6, wherein:   The notches are at least two notches, and the dielectric resonant element has two cross sections perpendicular to the height direction due to the two notches and parallel to each other. 8. The method for manufacturing a dielectric resonator according to claim 7, wherein the dielectric resonator is formed on opposing surfaces of the body resonator element.

Images