JPH08293711A - Dielectric resonator - Google Patents

Abstract

PURPOSE: To facilitate the control of a resonant frequency, to secure air-tightness of a case, to suppress the generation of frequency deviation and to facilitate the correction of frequency deviation by changing the position of a metal plate with a deformed piezoelectric element, and changing the resonant frequency with a deformed electromagnetic field generated around a dielectric resonant element. CONSTITUTION: A through electrode 10 having air-tight structure is fitted to a metal case 3, this electrode 10 and a piezoelectric element 4 are electrically connected and when power is supplied from this electrode 10, the form of the piezoelectric element 4 is changed. Besides, a metal plate 5 is fitted to the piezoelectric element 4, when the form of the piezoelectric element 4 is changed, the position of the metal plate 5 is changed, a distance between the metal plate 5 and a dielectric resonant element 1 is changed and the resonant frequency is changed by deforming the electromagnetic field generated around the dielectric resonant element 1 corresponding to the change of this distance. Further, the resonant frequency can be electrically controlled by controlling the change amount of the piezoelectric element 4 corresponding to the current value of the power source to be supplied.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dielectric resonator, and more particularly, to a means for adjusting the frequency of a dielectric resonator used in, for example, a dielectric resonant oscillator for generating microwaves.

[0002]

2. Description of the Related Art A dielectric resonator is often used in a resonance circuit of a voltage controlled oscillation circuit which is a microwave oscillation circuit. FIG. 3 is a diagram schematically showing the configuration of a conventional dielectric resonator of this type. In the figure, 1 is a dielectric resonator, 2 is a dielectric substrate that constitutes a resonance circuit, and 3 is a resonance circuit mounted. A metal case (stored) and 8 are frequency adjusting screws.

The dielectric resonator 1 resonates at a desired frequency and functions as a resonance circuit. In the resonance mode of such a cylindrical resonator 1, the shape of the metal case 3 greatly affects the resonance frequency. Therefore, after mounting the resonance circuit, the resonance frequency is adjusted by the frequency adjusting screw 8 provided on the upper portion of the metal case 3.

[0004]

In the conventional dielectric resonator as described above, the adjustment of the resonance frequency is mechanically operated by adjusting the adjustment screw provided on the upper part of the case to change the shape of the upper part of the resonator. Since it is adjusted, it takes a lot of work to adjust it. Also, due to the structure of the case with the adjustment screw attached,
Hermetic seal due to the problem of airtightness
The structure is difficult. Further, there is a problem that the adjustment screw is displaced due to the vibration from the outside and the frequency is apt to shift.

The present invention has been made to solve the above problems, and the resonance frequency can be easily adjusted, the airtightness of the case can be sufficiently ensured, and the frequency shift is unlikely to occur.
It is an object of the present invention to provide a dielectric resonator whose frequency can be corrected easily.

[0006]

A dielectric resonator according to the present invention includes a piezoelectric element and a metal plate provided between a mounting case and a dielectric resonator, and a piezoelectric element mounted on the piezoelectric element from outside the mounting case. Means for supplying electric power while maintaining airtightness, and changing the current value of the electric power supplied to the piezoelectric element to deform the piezoelectric element and change the position of the metal plate, thereby causing the dielectric resonance. The configuration is characterized in that the resonance frequency is changed by deforming the electromagnetic field generated around the child.

Further, it is provided with a dielectric and heating means provided between the mounting case and the dielectric resonator, and means for supplying power to the heating means from outside the mounting case while maintaining airtightness of the case. , The temperature of the dielectric is changed by changing the current value of the power source supplied to the heating means, the dielectric constant is changed, and the electromagnetic field generated around the dielectric resonator is deformed to cause resonance. The feature is that the frequency is changed.

Further, means for measuring the deviation of the resonance frequency, means for determining the current value of the power supply to be supplied from the deviation of the frequency measured by this means, and means for automatically correcting the deviation of the resonance frequency by feedback control. It is characterized by having and.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing an embodiment of the present invention, in which 1 is a dielectric resonator, 2 is a dielectric substrate that constitutes a resonance circuit, 3 is a metal case for housing the resonance circuit, and 4 is a piezoelectric element. Elements, 5 are metal plates, and 10 are through electrodes. A through electrode 10 having an airtight structure is attached to the metal case 3, the electrode 10 and the piezoelectric element 4 are electrically connected, and when a power is supplied from the electrode 10, the shape of the piezoelectric element 4 is changed. Change.

A metal plate 5 is attached to the piezoelectric element 4, and when the shape of the piezoelectric element 4 changes, the position of the metal plate 5 changes, and the distance between the metal plate 5 and the dielectric resonator 1 is increased. And the resonance frequency can be changed by deforming the electromagnetic field generated around the dielectric resonator 1 by the change of the distance. Further, the amount of change of the piezoelectric element 4 can be adjusted by the current value of the power source to be fed, and therefore the resonance frequency can be electrically adjusted by adjusting this current value. Note that, unlike the conventional configuration shown in FIG. 3, only the through electrode 10 having a completely airtight structure can penetrate the metal case 3, so that the metal case 3
Can have a sufficiently airtight structure.

FIG. 2 is a diagram showing another embodiment of the present invention. In the figure, the same reference numerals as in FIG. 1 designate the same or corresponding parts, 6 is a dielectric sheet, and 7 is a heating means (for example, a heater). Is. A through electrode 10 having a completely airtight structure is attached to the metal case 3, and the electrode 10 and the heater 7 are electrically connected to each other. When power is supplied from the electrode 10, the heater 7 generates heat. This changes the temperature of the dielectric sheet 6. The dielectric sheet 6 is made of a dielectric material having a relatively large change in permittivity with respect to temperature change, and the heater 7 can adjust its heat generation temperature by the current value of the power source to be fed. The dielectric constant of the dielectric sheet 6 can be freely changed by the value. Then, due to the change in the dielectric constant, the electromagnetic field generated around the dielectric resonator 1 can be deformed to change the resonance frequency. Therefore, by adjusting the current value, the resonance frequency can be changed electrically. Can be adjusted to. Also, the through electrode 1
Since 0 has an airtight structure as in the embodiment shown in FIG. 1, the metal case 3 can have a sufficiently airtight structure.

The dielectric resonator according to the above embodiment is
It is possible to electrically correct the deviation of the resonance frequency due to environmental changes, but go further to measure the deviation of the frequency, determine the current value to be supplied from this measurement value, perform feedback control, and make automatic correction ( It is also possible (not shown).

[0013]

As described above, the dielectric resonator of the present invention is
Since the resonance frequency is adjusted by electric means, the frequency can be adjusted very easily, and the hermetic seal structure in which the case is sufficiently airtight can be easily realized. Further, since there is no mechanical adjustment means such as a screw, the frequency shift due to external vibration is reduced, and the frequency shift due to environmental changes can be easily corrected.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of the present invention.

FIG. 2 is a diagram showing another embodiment of the present invention.

FIG. 3 is a diagram showing a configuration of a conventional dielectric resonator.

[Explanation of symbols]

 1 Dielectric Resonator 2 Dielectric Substrate 3 Metal Case 4 Piezoelectric Element 5 Metal Plate 6 Dielectric Sheet 7 Heater 10 Through Electrode

Claims (3)

[Claims] 1. A dielectric resonator in which a dielectric substrate and a dielectric resonator are provided in a mounting case, and an electromagnetic field generated around the dielectric resonator is deformed to change a resonance frequency. A piezoelectric element and a metal plate provided between the mounting case and the dielectric resonator; and a means for supplying power to the piezoelectric element from outside the mounting case while maintaining the airtightness of the case. The piezoelectric element is deformed by changing the current value of the power supply supplied to the position of the metal plate, and the electromagnetic field generated around the dielectric resonator is deformed to change the resonance frequency. A dielectric resonator characterized by: 2. A dielectric resonator in which a dielectric substrate and a dielectric resonator are provided in a mounting case, and an electromagnetic field generated around the dielectric resonator is deformed to change a resonance frequency. The heating means includes a dielectric and heating means provided between the mounting case and the dielectric resonator, and means for supplying power to the heating means from outside the mounting case while maintaining airtightness of the case. By changing the current value of the power supply to change the temperature of the dielectric and change its dielectric constant,
A dielectric resonator, wherein an electromagnetic field generated around the dielectric resonator is deformed to change a resonance frequency. 3. A means for measuring the deviation of the resonance frequency, a means for determining the current value of the power source from the deviation of the frequency measured by this means, and a means for automatically correcting the deviation of the resonance frequency by feedback control. Claim 1 characterized by the above-mentioned.
2. A dielectric resonator according to item 2 above.