JPH0629707A - Resonator - Google Patents

Abstract

PURPOSE:To provide the resonator, which is used in various communication apparatus or the like and is small-sized and has a small loss and has a harmonic suppression effect, in the simple production process which does not require a high controllability. CONSTITUTION:The coplanar guide constitution is adopted where a resonance conductor 12 and an grounding conductor 13 constituting the resonator can be formed on the same plane of a dielectric substrate 11, and the characteristic impedance of a line is stepwise changed in an open part 12A and a short-circuit part 12B, thereby realizing the resonator, which is small-sized and has a small loss and the harmonic suppression effect, in the simple production process which does not require a high controllability.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a compact and low loss resonator used in a high frequency band.

[0002]

2. Description of the Related Art In recent years, in the high frequency band, the characteristic impedance of the line is uniform and one end is opened and one end is shorted.
A two-wavelength microstrip line resonator is widely used. However, the 1/4 wavelength resonator is an odd multiple,
Since the two-wavelength resonator resonates even at an integral multiple, it is not suitable as an output filter for a non-linear circuit because it cannot suppress harmonics. To solve this problem, Japanese Patent Laid-Open No. 52-1774
The step resonator shown in Japanese Patent No. 8 is used.

A conventional step resonator will be described below. FIG. 5 shows a conventional microstrip line type step resonator. FIG. 5A is a perspective view.
(B) is a top view. In FIGS. 5A and 5B,
Reference numeral 1 is a dielectric substrate, 2 is a resonance conductor, and 3 is a ground conductor.

Regarding the resonator configured as described above,
The operation will be described below. The conventional step resonator is a microstrip line type resonator with one end open and one end shorted, and the characteristic impedance of the open part is lower than the characteristic impedance of the short part. That is, the impedance ratio of the open portion to the short-circuited portion becomes 1 or less. An open-ended and short-circuited step resonator with an impedance ratio of 1 or less is
It is known that the resonator length is shorter than 1/4 wavelength and the higher-order resonance frequency shifts from an odd multiple to a higher one.

[0005]

However, in the above-mentioned conventional configuration, the resonator length is shorter than 1/4 wavelength by setting the impedance ratio to 1 or less, and the higher resonance frequency is increased from odd multiple to higher. Although it can be shifted and has a harmonic suppression effect, the grounding conductor 3 is not on the same plane as the resonance conductor 2, so grounding is ensured via the end face or a hole is formed at the short-circuited end. You have to secure a ground,
The manufacturing process becomes complicated. In particular, when a superconductor is used as the conductor, the superconducting film on the other surface must be formed so as not to deteriorate the already formed superconducting film, which requires high controllability in manufacturing. However, there was a problem that manufacturing was difficult.

The present invention solves the above-mentioned problems of the prior art by a simple manufacturing process that does not require high controllability.
It is an object of the present invention to provide a resonator having a small size, a low loss, and a harmonic suppression effect.

[0007]

In order to achieve this object, the present invention uses a material such as a superconductor which has low loss but requires high controllability in film forming conditions.
The resonance conductor and the ground conductor have a coplanar guide structure in which they can be formed on the same plane of the dielectric substrate, and the characteristic impedance of the line is changed stepwise between the open part and the shorted part.

[0008]

The present invention has the above-mentioned constitution, and even if it is a material such as a superconductor having a low loss, but a high controllability is required in the film forming condition,
In order to easily form the resonator, the resonance conductor and the ground conductor forming the resonator are formed on the same plane of the dielectric substrate, and the coplanar guide structure is adopted. The dance ratio is set to 1 or less (the characteristic impedance of the open section line is made lower than that of the short circuit section), and the impedance ratio is set to 1 or more so that a low loss resonator can be realized. Characteristics of short circuit Impedance
By changing the characteristic impedance of the line in steps, such as making the dance lower than the open part), a simple manufacturing process that does not require high controllability and a compact, low-loss, harmonic suppression effect. A resonator can be realized.

[0009]

(Embodiment 1) A first embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a resonator according to a first embodiment of the present invention, FIG. 1 (a) is a perspective view of the resonator according to the first embodiment of the present invention, and FIG. 1 (b) is a top view. is there. Figure 1
In (a) and (b), 11 is a dielectric substrate. 1
Reference numeral 2 is a resonance conductor made of a superconducting thin film, and the open end portion 12A has a thick line width and the short circuit portion 12B has a thin line width. Reference numeral 13 is a ground conductor made of a superconducting thin film, which is connected to the resonance conductor 12 at the short-circuited portion 12B and is formed so as to surround the resonance conductor 12 with a certain space. The resonance conductor 12 and the ground conductor 13 are integrally formed on the same plane of the dielectric substrate 11, and the facing distance between the resonance conductor 12 and the ground conductor 13 at the open end portion 12A is shorter than that at the short circuit portion 12B.

Regarding the resonator configured as described above,
The operation will be described. Similar to the step resonator shown in the conventional example, it is a resonator with one end open and one end shorted, and the open part 12A
The characteristic impedance is that the line width is thick and the ground conductor 13
Since the distance between and is short, it is low,
The dance is high because the track width is narrow and the distance to the ground conductor 13 is wide. Therefore, the impedance of the open portion with respect to the short-circuit portion B
The dance ratio is 1 or less. A step resonator having an open-ended and short-circuited one end with an impedance ratio of 1 or less has a resonator length of 1 /
Shorter than 4 wavelengths, the higher resonance frequency also shifts from an odd multiple to a higher one.

As described above, in the resonator according to this embodiment, the resonance conductor 12 and the ground conductor 13 are formed on the same plane of the dielectric substrate 11, and the ratio of the characteristic impedance of the open portion 12A to the short-circuit portion 12B is 1. Because of the following, it is possible to realize a small-sized, low-loss resonator having a harmonic suppression effect by a simple manufacturing process without requiring high controllability.

As described above, according to the present embodiment, the resonance conductor 12 and the ground conductor 13 which constitute the resonator are connected to the dielectric substrate 1
1, the characteristic impedance of the open portion 12A is low by widening the line width of the resonance conductor and at the same time narrowing the distance to the ground conductor. On the other hand, the characteristic impedance of the short circuit portion 12B is low. Higher by narrowing the width and widening the distance to the ground conductor at the same time, that is, by setting the impedance ratio of the open portion to the short-circuit portion 12B to 1 or less, high controllability is not required, and a simple manufacturing process is performed. A compact, low-loss resonator having a harmonic suppression effect can be realized.

(Second Embodiment) A second embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 shows a resonator according to a second embodiment of the present invention, FIG. 2 (a) is a perspective view of the resonator according to the second embodiment of the present invention, and FIG. 2 (b) is a top view. is there. 2 is different from the configuration of FIG. 1 in that the width of the resonance conductor 22 is made uniform and the notch of the ground conductor 23 with respect to the resonance conductor 22 is changed to change the distance between the resonance conductor 22 and the ground conductor 23. The characteristic impedance of the line is changed in steps. Then, the resonance conductor 22 and the ground conductor 23 are integrally formed on the same plane of the dielectric substrate 21, and the resonance conductor 22 and the ground conductor 2 at the open end 22A.
The facing distance to 3 is shorter than that of the short-circuit portion 22B.

Regarding the resonator constructed as described above,
The operation will be described below. Similar to the step resonator of FIG. 1, the open end 22A is a short end resonator, and the characteristic impedance of the open part 22A is low because the distance to the ground conductor 23 is small. Therefore, the characteristic impedance of the short part 22B is low. Since the distance to the ground conductor 23 is large, the distance becomes high, and the impedance ratio of the open portion to the short-circuit portion 22B becomes a step resonator of 1 or less as in FIG. The step resonator having an impedance ratio of 1 or less has a resonator length shorter than 1/4 wavelength as in the resonator shown in FIG. 1, and the higher resonance frequency shifts from an odd multiple to a higher one.

As described above, the resonance conductor 22 and the ground conductor 23 forming the resonator are formed on the same plane of the dielectric substrate 21, and the resonance conductor 22 is uniform, but the distance from the ground conductor is changed. , By changing the characteristic impedance of the line substantially in a stepwise manner and setting the impedance ratio to 1 or less, a compact resonator that does not require high controllability and has a harmonic suppression effect in a simple manufacturing process. Is feasible.

(Embodiment 3) A third embodiment of the present invention will be described below with reference to the drawings.

FIG. 3 shows a resonator according to a third embodiment of the present invention, and FIGS. 3A and 3B are top views of the resonator according to the third embodiment of the present invention. 1 and 2 in FIG.
The difference from the configuration is that the characteristic impedance of each short-circuit portion 32B and 35B is made lower than the characteristic impedance of each open portion 32A, 35A. Specifically, as shown in the same figure, in FIG.
The open end portion 32A has a narrow line width, and the short circuit portion 32B has a wide line width. Furthermore, the open end 32A
The opposing distance between the resonance conductor 32 and the ground conductor 33 at is wider than that of the short-circuit portion 32B.
On the other hand, in the case of FIG. 3B, the width of the resonance conductor 35 is made uniform, and the cut distance of the ground conductor 36 with respect to the resonance conductor 35 is changed to change the distance between the resonance conductor 35 and the ground conductor 36. Resonant conductor 3 at open end 32A
The facing distance between 2 and the ground conductor 33 is wider than that of the short-circuit portion 32B.

Regarding the resonator configured as described above,
The operation will be described below. Similar to the step resonator shown in FIGS. 1 and 2, the resonator has one open end and one short circuit.
In the case of the configuration of (a), the width of the resonance conductor 32 and the ground conductor 3
The characteristic impedance of the short circuit portion 32B is set lower than the characteristic impedance of the open circuit portion 32A, that is, the impedance ratio of the open circuit portion 32A to the short circuit portion 32B is set to 1 or more by changing both the distance from the short circuit portion 32B. On the other hand, FIG. 3 (b)
The width of the resonance conductor 35 is uniform, and only the distance from the ground conductor 36 is changed to open the open portion 35A with respect to the short circuit portion 35B.
Has an impedance ratio of 1 or more.

Such a step resonator having an impedance ratio of 1 or more is different from the resonator shown in FIGS.
The resonator length is longer than ¼ wavelength, and the higher-order resonance frequency also shifts from an odd multiple to a lower one. Further, the resonator having the shape shown in FIG. 3A can reduce the loss in the short-circuited portion where the conductor loss is remarkable, and can realize a low-loss resonator.

As described above, the resonance conductor and the ground conductor forming the resonator are formed on the same plane of the dielectric substrate, and the distance between the resonance conductor and the ground conductor or only the distance from the ground conductor is changed. By changing the characteristic impedance of the line stepwise and setting the impedance ratio to 1 or more, a resonator having a harmonic suppression effect can be realized in a simple manufacturing process without requiring high controllability. .

(Embodiment 4) A fourth embodiment of the present invention will be described below with reference to the drawings.

FIG. 4 shows a resonator according to an embodiment of the present invention, and FIGS. 4A and 4B are top views of the resonator according to the fourth embodiment of the present invention. In FIG. 4, FIGS.
The difference from the configuration of 3 is that the resonator is open at both ends. 4A, 41 is a dielectric substrate, 42 is a resonance conductor, 43 is a ground conductor, and in FIG. 4B, 44 is a dielectric substrate, 45 is a resonance conductor, and 46 is a ground conductor.
Both (a) and (b) are configured on the same plane.

Regarding the resonator configured as described above,
The operation will be described below. Unlike the step resonator of FIGS. 1 and 2, the resonator is open at both ends. In FIG. 4A, the width of the resonance conductor 42 is uniform, and only the distance (opposite distance) to the ground conductor 43 is changed to change the characteristic impedance of the virtual short-circuited portion (central portion) 42B to the open portion. It is higher than the characteristic impedance of 42A, that is, the impedance ratio of both open portions 42A to the short circuit portion 42B is 1 or less. In FIG. 4B, the width of the short-circuited portion 42B of the resonance conductor 45 is made larger than the width of both open portions 42A, and the impedance ratio of both open portions 42A to the short-circuited portion 42B is set to 1 or more.

The step resonator having an impedance ratio of 1 or less shown in FIG. 4A has a resonator length of ½ wavelength, as is apparent from the embodiments of the resonator shown in FIGS. It is possible to realize a small-sized resonator that is shorter and shifts the higher-order resonance frequency from an odd multiple to a higher one and has a harmonic suppression effect.

On the other hand, the step resonator having an impedance ratio of 1 or more shown in FIG. 4 (b) has a resonator length of 1 as is apparent from the embodiment of the resonator shown in FIG. 3 (a). / 2 wavelength, high-order resonance frequency shifts from odd multiples to lower ones, and loss of short-circuit part where conductor loss is remarkable can be reduced, realizing low loss resonator with harmonic suppression effect. it can.

As described above, according to each of the first to fourth embodiments, the resonance conductor and the ground conductor forming the resonator are formed on the same plane of the dielectric substrate, and only the distance from the ground conductor or By changing the distance from the resonance conductor and the ground conductor and changing the characteristic impedance of the line in steps, it is not necessary to have high controllability in the manufacturing process, and it is a compact, low-loss device that has a harmonic suppression effect in a simple manufacturing process. Can be realized.

In the fourth embodiment, two types of resonator structures are shown, but needless to say, in view of the first to third embodiments, it is not limited to this embodiment. As a method of changing the characteristic impedance of the line in a stepwise manner, a method of changing only the distance to the ground conductor while keeping the line width constant, and a method of simultaneously changing both the line width and the distance to the ground conductor were shown. It goes without saying that the method of changing the impedance is not limited to this.

[0030]

As described above, the present invention has the coplanar guide structure in which the resonance conductor and the ground conductor forming the resonator can be formed on the same plane of the dielectric substrate, and the characteristic impedance of the line is defined as the open portion. By adopting a configuration that changes stepwise at the short-circuited part, even a material with low loss such as a superconductor, but high controllability in film forming conditions does not require high controllability and can be manufactured in a simple manufacturing process. A resonator having a low loss and a harmonic suppression effect can be realized.

[Brief description of drawings]

FIG. 1 is a perspective view and a top view of a resonator according to a first embodiment of the present invention.

FIG. 2 is a perspective view and a top view of a resonator according to a second embodiment of the present invention.

FIG. 3 is a top view of a resonator according to a third embodiment of the present invention.

FIG. 4 is a top view of a resonator according to a fourth embodiment of the present invention.

FIG. 5 is a perspective view and a top view of a conventional resonator.

[Explanation of symbols]

 11, 21, 31, 34, 41, 44 Dielectric substrate 12, 22, 32, 35, 42, 45 Resonant conductor 13, 23, 33, 36, 43, 46 Ground conductor

Claims (4)

[Claims] 1. A dielectric substrate comprising a central conductor and a ground conductor formed on the same plane, and characteristic impedances of an open portion and a short portion formed by the central conductor and the ground conductor are different stepwise. A resonator characterized by being present. 2. The resonator according to claim 1, wherein one end is open and one end is short circuit. 3. The resonator according to claim 1, wherein both ends are open. 4. The resonator according to claim 1, wherein the conductor portion is composed of a superconducting thin film.