JPS58204602A - Method for adjusting resonance frequency of dielectric coaxial resonator - Google Patents

Abstract

PURPOSE:To adjust the resonance frequency without deteriorating the Q of a resonator, by removing a part of a short-circuit electrode of the dielectric coaxial resonator using a cylindrical ceramic dielectric. CONSTITUTION:After the length L of the dielectric 11 is polished as 1/4 of the wavelength determined by the resonance frequency fO being the target of adjustment, electrodes 14, 15 and the short-circuit electrode 16 are formed on its inner circumferential surface 12, its outer circumferential surface 13 and its end surfaces respectively, and the resonance frequency fOX is measured. When fOX<fO, an opening surface 18 of the dielectric 11 is polished for the adjustment as a conventional way. When fOX>fO, a part of the short-circuit electrode 16 is polished to form a removed part 22, and the area S is adjusted so as to attain fOX=fO. In decreasing the resonance frequency in this way, since a part of the short-circuit electrode is removed for the adjustment, the resonance frequency is adjusted without deteriorating the Q of the resonator.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for adjusting the resonance frequency of a dielectric coaxial resonator using a cylindrical ceramic dielectric.

A dielectric coaxial resonator using a ceramic dielectric generally has a cylindrical ceramic dielectric 11 as shown in FIG.
Electrodes 14 and 1 are provided on the inner circumferential surface 12 and outer circumferential surface 13, respectively.
5, and a shorting electrode 16 for shorting these electrodes 14 and 15 is provided on one end surface 17 of the ceramic dielectric 11.

Conventionally, in order to adjust the resonant frequency of a dielectric coaxial resonator having the above-mentioned configuration, the following methods were used: (1) To increase the resonant frequency, a part of the open surface 18 of the ceramic dielectric 11 was removed, or (2) the resonant frequency was increased. When lowering the ceramic dielectric body 11, a method such as pasting dielectric material or a metal piece on the open surface 18 of the ceramic dielectric body 11 has been adopted.

By the way, if the resonant frequency is adjusted by the resonant frequency adjustment method (2), it is troublesome to attach the dielectric or metal piece, and the Q of the dielectric coaxial resonator is lowered. Therefore, when adjusting the resonant frequency, the resonant frequency of the 1W dielectric coaxial resonator must be kept low in advance.

The resonant frequency is adjusted using the method (2).

However, when the resonant frequency is adjusted by method (2), care must be taken not to remove too much of the ceramic dielectric 11, which poses a problem in that adjusting the resonant frequency takes a lot of time and effort.

The present invention has been made to solve the above-mentioned problems in the conventional method for adjusting the resonant frequency of an induced IF coaxial resonator. To easily adjust the resonant frequency of a 1-D dielectric coaxial resonator using a ceramic dielectric without greatly deteriorating its Q.

The gist of the present invention is to provide electrodes on the inner and outer peripheral surfaces of a cylindrical ceramic dielectric 1F having a length a of a quarter wavelength, and to connect a short-circuiting electrode to short-circuit these two electrodes to the ceramic dielectric body. A method for adjusting the resonant frequency of a dielectric coaxial resonator provided on one end face of a dielectric 1E body, the short circuit 1,
1. This is a method for adjusting the resonant frequency of a dielectric coaxial resonator, which is characterized in that the resonance frequency is lowered by removing the pole or the ceramic dielectric body.

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

In the present invention, the dielectric J shown in FIG. , electrodes 14 are provided on the inner peripheral portion 12, outer peripheral surface 13 and end surface 17, respectively.
．． 15 and the short-circuit electrode 16 are formed by a well-known method, and their resonance frequency f. Measure X.

As a result of the above measurement, if f, x < f, then the open surface 18 of the ceramic dielectric 11 is set to f. Polish until it becomes x-fo.

Contrary to the above, if f, x>f, as shown in FIG. By doing so (at this time, a portion of the ceramic dielectric 11 may also be removed), a removed portion 22 is formed and its area S is adjusted to be fox-fo.

As described above, the resonator of the dielectric coaxial resonator □ By adjusting the wave number IO, the resonant frequency f.

When lowering the resonant frequency f, as shown by curve t1 in FIG. Even if the change Δf becomes large, the decrease in Q is relatively small, whereas the open surface 1 of the ceramic dielectric 11
When a dielectric or a metal piece is attached to 8, the Q drops rapidly as shown in song 1mtt.

Further, when the area S of the removing portion 22 is increased, as shown in FIG. 4, the resonance frequency f decreases and the Q also decreases, but the rate at which Q decreases is relatively small.

On the other hand, when a part of the electrode 14 formed on the inner peripheral part 12 of the ceramic dielectric 11 of the dielectric 7PL coaxial resonance IEG 21 is removed, the area 81 increases by half as much as shown in FIG. However, as the resonance frequency f decreases, Q also decreases rapidly.Contrary to the above, when a part of the electrode 15 formed on the outer peripheral surface I3 of the ceramic dielectric 11 is removed, the sixth
As shown in the figure, even if the area S2 increases, the resonant frequency f. and Q hardly change.

Therefore, as shown in FIG. 2, by simply removing a portion of the short-circuiting electrode 16 formed on the end surface 17 of the ceramic dielectric 11 and adjusting the area S of the removed portion 22, the dielectric coaxial resonator can be The resonant frequency f can be easily adjusted without significantly deteriorating Q. can be adjusted to the desired value.

In the above embodiments, the ceramic dielectric 11 is shown as having a cylindrical shape, but it may also have a triangular, quadrangular or polygonal cylindrical shape.

Further, the present invention can also be applied to a dielectric coaxial resonator in which the length of the ceramic dielectric 11 is a half wavelength; however, in such a dielectric coaxial resonator, specifically, Although not shown, by removing a part of the electrode on the outer peripheral surface of the ceramic diode 7 and adjusting its area, the resonant frequency f can be adjusted in the same manner as above. can be adjusted.

As is clear from the detailed description above, the present invention
This is a resonant frequency adjustment method in which the resonant frequency is adjusted by removing a part of the short-circuit electrode of a dielectric coaxial resonator using a cylindrical ceramic dielectric having a length of a quarter wavelength.

In this way, by changing the area of the removed portion of the short-circuit electrode of the dielectric coaxial resonator, the resonant frequency can be greatly changed without substantially deteriorating the Q of the dielectric coaxial resonator, and the short-circuit By removing part or the open end of the electrode or ceramic dielectric with the same tool or technique, it is possible to freely raise or lower the resonant frequency, making it extremely easy to adjust the common four-wire frequency. .

Furthermore, since there is no need to attach dielectric chips or metal chips with adhesive, problems such as deterioration of characteristics of the dielectric coaxial resonator due to deterioration of the 1θ adhesive can be eliminated.

[Brief explanation of drawings]

Fig. 1 is a vertical cross-sectional view showing the structure of a dielectric coaxial j (oscillator), and Fig. 2 is a vertical cross-sectional view showing the structure of a dielectric coaxial IQt+ J (oscillator) to which the method of the present invention is applied.
A perspective view of the resonator, FIG. 3 is an explanatory diagram of the comparison result of the Q deterioration characteristics of the dielectric resonator between the resonant frequency adjustment method according to the present invention and the conventional resonant frequency adjustment method, and @Fig. Figures 5 and 6 are graphs showing the change in Q and resonance frequency of a dielectric resonator according to this method of adjusting the resonance frequency, respectively, with the inner and outer electrodes of the ceramic dielectric being partially removed. 11...Ceramic dielectric, 14.15...Electrode,
16. Short circuit electrode, 21... dielectric coaxial resonator, 22.
...Removal section. Patent applicant Murata Manufacturing Co., Ltd. Agent
Patent attorney Maeda Hao and two others Figure 1 Figure 5 Figure 1114 Figure 16

Claims (1)

[Claims] (1) Electrodes are provided on the inner circumferential surface and outer circumferential surface of a cylindrical ceramic dielectric having a length of a quarter wavelength, and a shorting electrode is placed on one end surface of the ceramic dielectric to short-circuit these two electrodes. A method for adjusting the resonant frequency of a dielectric coaxial resonator provided in a dielectric coaxial resonator, the method comprising: reducing the resonant frequency by removing the short-circuited electrode or the ceramic dielectric.