JPH0529815A - Dielectric substance multiple line resonator - Google Patents

Abstract

PURPOSE:To improve the fluctuation of a resonance frequency due to the coupling with the outside for which had been conventionally caused only by the capacitive coupling of a 1/4 wavelength coaxial line. CONSTITUTION:Lines 9a, 9b where both ends are opened are made to go along with a resonance line 4 in which one end has short-circuit and one end is opened in parallel and to couple with it so as to induce distribution. By combining the dielectric substance resonators having such basic constitutions in various forms, circuit devices having various kinds of functions such as various filters, a multiplexer, a power splitter are constituted. Thus, the fluctuation of resonance frequency by the coupling with the outside in this kinds of a circuit device can be drastically reduced as compared with that in the conventional resonator.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coaxial resonator or the like mainly used in the UHF band, in which a 1/4 wavelength line with one short circuit and one open circuit is provided in a dielectric block surrounded by a ground conductor. The present invention relates to a dielectric multi-line resonator, and in particular, is capable of remarkably reducing fluctuations in the resonance frequency caused by coupling with an external circuit, as compared with the related art.

[0002]

2. Description of the Related Art Conventionally, as an external circuit coupling means for a coaxial resonator based on a structure in which a 1/4 wavelength line with one short circuit and one open circuit is provided in a dielectric block surrounded by a ground conductor And because of their ease of manufacture, exclusively capacitive coupling means have been used. That is, FIG.
As shown in (a), in a typical coaxial resonator configured by the peripheral wall surface conductor 4 of the central hole 3 in the dielectric block 2 of the height 1/4 wavelength surrounded by the peripheral side surface conductor 1a and the bottom surface conductor 1b, In the above, the terminal conductor 6 supported by the insulator 5 is inserted into the upper end portion of the center hole 3, and the external terminal coupling is obtained by the capacitance between the peripheral wall surface conductor 4 acting as a resonance line and the terminal conductor 6. Alternatively, as shown in FIG. 1 (b),
In the coaxial resonator having the same structure as described above, the terminal conductor 8 is inserted into the small hole 7 provided in the upper end portion of the dielectric block 2 in the vicinity of the peripheral wall surface conductor 4, and the external terminal is formed by the capacitance between the conductors 4 and 8. I was getting a bond.

[0003]

However, the above-mentioned capacitive external coupling to the coaxial resonator has a simple structure and is easy to manufacture, and stable coupling is obtained, but the resonant coupling due to the coupling with the external circuit is obtained. Since there is a large change in frequency and the change in the degree of coupling due to the shape and size is large, there is a problem that precision processing is required.

On the other hand, regarding the change of the resonance frequency due to the degree of coupling, the inductive coupling by the coil is more tolerant and the coupling with the external circuit is more stable. However, the conventional construction takes time and labor for the mass production. There was a difficulty that it was not suitable.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art and to have a simple structure, easy to manufacture and suitable for mass production, mainly by inductive coupling, depending on the degree of coupling with an external circuit. It is an object of the present invention to provide a dielectric multi-line resonator having a basic configuration of a coaxial resonator in which the resonance frequency does not change.

That is, the dielectric multi-line resonator of the present invention is
Basically, a coupling conductor that penetrates the dielectric block of the coaxial resonator and is in parallel with and close to the center resonance conductor is inserted with both ends open, and the distribution that mainly acts inductively with the center resonance conductor The upper and lower ends of a dielectric block having upper and lower end faces that face each other in parallel with each other with a wavelength separated by about 1/4 of the dielectric and conductive peripheral side faces perpendicular to the upper and lower end faces are provided. A plurality of conductive lines each having an axis substantially perpendicular to the upper and lower end faces are provided between the surfaces, and at least one of the plurality of conductive lines serves as a resonance line and has one end on the same side. Are electrically connected to the conductive peripheral side surface and the other ends thereof are opened together, and at least one other conductive line that is adjacently coupled to the resonant line is connected. Together together to open the ends as line, it is characterized in that so as to connect the open end of the other end side of the coupling line to an external circuit.

[0007]

Therefore, in the dielectric multi-line resonator of the present invention, the resonance frequency does not change due to the coupling with the external circuit, and the input / output impedance can be set and the size can be reduced by the simple structure which is easy to manufacture. A simple coaxial resonator can be easily realized.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the accompanying drawings. FIG. 2 shows the basic structure of the coaxial resonator according to the present invention, which corresponds to the basic structure of the conventional coaxial resonator shown in FIG. That is, as shown in FIG. 2 (a), a typical coaxial structure constituted by the peripheral wall surface conductor 4 of the center hole 3 in the dielectric block 2 of the height 1/4 wavelength surrounded by the peripheral side surface conductor 1a and the bottom surface conductor 1b. In the basic configuration in which the present invention is applied to the resonator, the through hole 9a that is parallel to and close to the peripheral wall surface conductor 4 of the central hole 3 that functions as a resonance line.
Is provided in the dielectric block 2 and a conductor is inserted into the through hole 9a, or, similarly to the resonance line 4, the inner wall surface of the through hole 9a is made conductive to form the coupled line 9b. At this time, the peripheral portion of the opening of the through hole 9a in the bottom conductor 1b is made non-conductive over an appropriate range, and both ends of the through hole inner wall surface conductor 9a having a height of 1/4 wavelength are opened.

In order to impart conductivity to the inner wall surface of the through hole, a silver paste is applied and baked as is customary in such a case, but a coating film is applied up to the non-conductive region 10 at the periphery of the opening of the through hole. It is preferable to expand it. The impedance of the coupling line formed by the through-hole inner wall surface conductor 9a is
It can be set appropriately by the shape size of the through hole, the distance between the resonance conductor 4 and the peripheral side surface conductor 1a, or by mixing a resistance material with silver paste, and impedance matching with the external circuit to be coupled can be achieved. Can be planned.

The open end of the coupled line 9a having such a structure on the open end side of the resonance line is as shown in the perspective view of FIG. 2 (b).
It is terminated by a load L corresponding to the characteristic impedance Z ₀ of the external circuit and coupled with the external circuit.

Therefore, a distributed coupling is formed between the resonant line 4 made of a 1/4 wavelength conductor having one short circuit and one open circuit, and the coupled line 9b which is parallel and close to the resonant line 4. Capacitive coupling is dominant on the open end side from the point,
Inductive coupling is dominant on the short-circuit end side from the midpoint. Therefore, in the present invention intended to reduce the fluctuation of the resonance frequency due to the coupling with the external circuit by inductively coupling the resonance line 4, the length of the coupling line 9b is
The length from the open end of the resonance line 4 to the midpoint is set to a length exceeding 1/8 wavelength, but in practice it is set to 1/4 wavelength to minimize the change in resonance frequency due to external coupling. Is preferred.

The equivalent circuit of the basic structure of the resonator of the present invention has a form in which a series resonance circuit is connected in series to a parallel resonance circuit equivalent to the resonance line 4, as shown in FIG. 2 (c). Therefore, the change in the capacitance of one resonance circuit impedance due to the change in frequency and the change in the resonance circuit impedance of the other resonance circuit are canceled out, so that there is no impedance change to the coupled external circuit, and the external coupling is wide band. To obtain good bonding characteristics.

The resonator of the present invention having the above-mentioned basic structure is shown in FIG.
Corresponding to the stripline configuration shown in (a), the open end is
Length that exceeds 1/8 wavelength for 1/4 wavelength resonant line R

[Outer 1] The operation of the coupling line C is similar to that of the configuration in which the open ends of the coupling lines C are staggered in parallel with each other. In a 1/4 wavelength resonant line with one end grounded and one end open, an inductive potential distribution is obtained on the ground end side from the midpoint, and a capacitive potential distribution is obtained on the open end side. If the coupled lines C are placed in parallel and close to each other with their ends being staggered,
As shown in, a broadband mutual coupling is obtained by the interaction of the capacitive potential distribution and the inductive potential distribution in each line over the entire length of the line, with the midpoint of the 1/8 wavelength as the boundary. On the contrary, as shown in FIG. 3 (c), when the open ends of both lines R and C are aligned and arranged close to each other, mutual repulsion between the capacitive potential distribution and the inductive potential distribution in each line is caused. Due to the action, no mutual bond can be obtained.

By applying the resonator of the present invention having a basic structure exhibiting good coupling characteristics as described above, a dielectric multi-line resonator composed of a plurality of lines is constructed in the same manner as in the conventional case, and the dielectric multi-line resonator is compared with the conventional case. Not only is it possible to obtain remarkably excellent characteristics in a stable manner, but it is also possible to simplify the structure and reduce the size. Several examples of specific configurations of such a dielectric multi-line resonator according to the present invention will be sequentially illustrated and described below.

The bandpass filter shown in FIG. 4 (a) is a perspective view, and a strip line having a corresponding structure is shown in FIG. 4 (b).
Two coupled lines 9a-1 (C- before and after one resonant line 4 (R)
1) and 9a-2 (C-2) are placed close to each other to serve as input / output lines so that a passband with a single peak characteristic can be obtained.

Further, the band-pass filter whose horizontal and vertical sections are shown in FIG. 5 has two resonance lines 4-1, 4 coupled to each other.
Two coupled lines 9a-1 and 9a-2 are arranged close to each other before and after 4-2 to serve as input / output lines, respectively, so that a passband having a bimodal characteristic can be obtained. The two resonance lines 4-1, 4
The -2 mutual coupling is generally capacitive coupling or inductive coupling, but the illustration is omitted, and the coupling between the resonance lines is the same in the following drawings.

Further, a Marsaplexer, whose perspective view is shown in FIG. 6 (a) and whose corresponding strip line is shown in FIG. 6 (b), is provided before and after the coupled line 9a-2 as an input line, respectively.
_Two resonance lines 4-1, 2 and 4-3, 4 having resonance frequencies f ₁ and f ₂ and mutually coupled are arranged close to each other, and a coupling line 9a- is arranged before and after the resonance line group. 1 and 9a
-3 are both arranged as output lines in close proximity to each other, and the high frequency powers of frequencies f ₁ and f ₂ mixed and supplied to the common input coupling line 9a-2 are separated from each other to separate each output coupling line 9a-1. And 9a-2 respectively. When the resonance frequencies f ₁ and f ₂ are the same, it operates as a power splitter. Also, FIG. 6 (a), the as is clear from (b), the height dielectric block 2, or the length of the resonant strip line R in accordance with the difference in resonant wavelength lambda _g1 and lambda _g2, respectively lambda _g1 Of course, / 4 and λ _g2 / 4.

Further, a trap filter shown in FIG. 7 (a) in a perspective view and having a strip line of a corresponding structure in FIG. 7 (b) is a resonance line 4 having a single-peak bandpass characteristic. A resonance line 4t having a resonance frequency corresponding to the blocking frequency f _t is arranged in the vicinity of the input coupling line 9a arranged in the vicinity thereof, and a partial region of the peripheral side surface conductor 1a close to the band pass resonance line 4 is arranged. The strip line 12 made non-conductive and attached to the non-conductive region is made to act as an output coupled line in the same manner as the coupled lines 9a, 9b in the basic configuration shown in FIG. 2 (a).

[0019]

As is apparent from the above description, according to the present invention, the fluctuation of the resonance frequency due to the coupling with the external circuit in the dielectric multi-line resonator based on the coaxial resonator is lower than that of the conventional one. This is a special feature that it can be significantly reduced, stable wideband coupling can be obtained, the structure of coupling means is much simpler than before, manufacturing is easy, and products with uniform characteristics can be easily obtained during mass production. The effect of can be raised.

[Brief description of drawings]

1A and 1B are cross-sectional views showing a conventional external connection mode for a coaxial resonator, respectively.

2 (a), (b) and (c) are a sectional view, a perspective view and an equivalent circuit diagram, respectively, showing the basic configuration of the dielectric multi-line resonator of the present invention.

3 (a) to 3 (c) are diagrams sequentially showing the operation principle of the external connection according to the present invention with respect to the resonance line.

4 (a) and 4 (b) are respectively a perspective view and an equivalent strip line diagram showing a configuration example of a bandpass filter according to the present invention.

5A and 5B are a horizontal cross-sectional view and a vertical cross-sectional view, respectively, showing another configuration example of the bandpass filter according to the present invention.

6A and 6B are a perspective view and an equivalent strip line diagram showing a configuration example of a multiplexer according to the present invention, respectively.

7A and 7B are a perspective view and an equivalent strip line diagram, respectively, showing a configuration example of a trap filter according to the present invention.

[Explanation of symbols]

1a Circumferential side conductor 1b Bottom conductor 2 Dielectric block 3 center hole 4 Inner wall surface conductor 5 insulator 6,8 terminal conductor 7 small holes 9a Through-hole inner wall conductor (coupled line) 9b coupled line 10 Non-conductive area R resonant line C coupling line L load S signal source M meter T trap track

Claims (10)

[Claims] 1. The upper and lower ends of the dielectric block having upper and lower end faces facing each other in parallel with each other with a wavelength of about 1/4 in parallel with each other and conductive peripheral side faces perpendicular to the upper and lower end faces. A plurality of conductive lines each having an axis substantially perpendicular to the surface are provided, and at least one conductive line of the plurality of conductive lines is used as a resonance line, and one end on the same side is the conductive peripheral side surface. Are electrically connected to each other and open at the other end thereof, and at least one other conductive line coupled adjacently to the resonance line is used as a coupling line and both ends thereof are opened. A dielectric multi-line resonator characterized in that the open end on the side of the other end is connected to an external circuit. 2. The resonance line is made substantially conductive to the inner wall surface of the perforations formed in the dielectric block so as to be substantially perpendicular to the upper and lower end surfaces, and the dielectric block on the one end side of the resonance line. 2. The dielectric multi-line resonator according to claim 1, wherein the end surface of said is made electrically conductive and electrically connected to said electrically conductive peripheral side surface and said electrically conductive inner wall surface. 3. The inner wall surface that is at least perpendicular to the upper and lower end surfaces and extends beyond the midpoint between the upper and lower end surfaces from the end surface on the other end side of the hole provided in the dielectric block is made conductive. The dielectric multi-line resonator according to claim 1, which is a coupled line. 4. An inner wall surface which is substantially perpendicular to the upper and lower end surfaces and is made conductive from an end surface on the other end side of a perforation provided in the dielectric block and at least beyond a midpoint between the upper and lower end surfaces. The dielectric multi-line resonator according to claim 2, wherein the conductive inner wall surface is a coupled line, and the conductive inner wall surface is electrically separated from the conductive end surface. 5. The inner wall surface between the upper and lower end surfaces of the perforation provided in the dielectric block substantially perpendicular to the upper and lower end surfaces is made conductive to form the coupled line, and the hole forming the coupled line is formed. 5. The dielectric multi-line resonator according to claim 4, wherein an end surface of the peripheral edge of the conductive opening on the side of the one end is made non-conductive. 6. An inner wall surface of a perforation provided in the dielectric block, which is close to the conductive peripheral side surface and is substantially perpendicular to the upper and lower end surfaces, is made conductive to form the resonance line. A portion adjacent to the resonance line in parallel is made non-conductive, and a conductive strip is attached to the non-conductive portion in parallel with the resonance line while being separated from other conductive portions. The dielectric multi-line resonator according to claim 1, wherein a strip is used as the coupling line. 7. At least one of the resonant lines that are sequentially coupled and two of the coupled lines that are respectively coupled to the resonant lines as input and output lines are sequentially arranged so as to act as a band pass filter. A dielectric multi-line resonator according to any one of the preceding claims. 8. The method according to claim 1, wherein the coupling lines respectively coupled to at least one resonance line act as input / output lines, and at least one of the resonance lines acts as a trap filter. 7. The dielectric multi-line resonator according to. 9. The two dielectric multi-line resonators according to claim 7, which function as band-pass filters for resonance frequencies different from each other, have the coupling lines that function as input lines in common and are opposite to each other. A dielectric multi-line resonator arranged on the side to act as a multiplexer. 10. The two dielectric multi-line resonators according to claim 7, which both act as band pass filters for the same resonance frequency, have the coupling lines acting as input lines in common and are opposite to each other. A dielectric multi-line resonator arranged on the side to act as a power splitter.