JPWO2020179046A1 - Resonator coupling structure and frequency filter - Google Patents

Abstract

The resonator coupling structure (100, 100a, 100b) is composed of a plate-shaped insulator (1) having a first layer (1a) and a second layer (1b) parallel to each other, and an insulator (1) on one side. A ground conductor (2a, 2b) arranged parallel to one surface, a strip conductor (4a) arranged on the first layer (1a) of the insulator (1), and one end having an open end, and an insulator (1). ) Is arranged in the first layer (1a) and is arranged in a position where a gap is provided from one end of the strip conductor (4a), and is arranged in the second layer (1b) of the insulator (1). A strip conductor (4b) having an open end at one end is provided, and one end of the strip conductor (4a) and one end of the strip conductor (4b) are arranged so as to be close to each other, and the floating conductor (5a) is provided. , Are arranged so as to overlap the strip conductor (4b) in the direction orthogonal to the second layer (1b).

Description

The present invention relates to resonators and frequency filters.

A frequency filter such as a microwave band or a millimeter wave band uses a strip conductor as a resonator to suppress signal loss due to the substrate material or to suppress manufacturing costs, and resonates with a dielectric substrate at the same frequency. Some are composed of a plane filter in which a plurality of strip conductors are arranged. A frequency filter composed of a planar filter is one in which a plurality of strip conductors are connected in series by electromagnetic field coupling by adjoining a plurality of strip conductors. A frequency filter using a planar filter is analytically calculated based on the prototype low-pass filter once the transfer function of the frequency filter is determined, the resonance angular frequency of the resonator, and between the resonator and the resonator. It can be easily designed based on the circuit parameters such as the coupling amount or the coupling amount between the resonator and the input / output line. Therefore, a frequency filter using a planar filter is widely used in the fields of communication equipment, radar equipment, and the like.

When designing a frequency filter using a planar filter, it is important to incorporate the circuit parameters obtained by circuit synthesis into the actual structure. In particular, since the coupling coefficient between the resonator and the resonator and the specific bandwidth of the frequency filter are in a proportional relationship, in order to enable the frequency filter to operate in a wider band, the resonator and the resonator should be used. In between, a larger coupling coefficient is needed.
However, when two strip conductors are arranged on the same layer of the dielectric substrate and vertically connected by electric field coupling, it is difficult to obtain a large coupling coefficient between the resonator and the resonator, that is, between the two strip conductors. .. Therefore, when two strip conductors are mounted at intervals that are feasible in manufacturing, a desired coupling coefficient may not be obtained. In order to solve such a problem, Patent Document 1 discloses a frequency filter in which two strip conductors are arranged in different layers of a dielectric substrate and vertically connected by electric field coupling.

Japanese Unexamined Patent Publication No. 2008-289113

However, like the frequency filter disclosed in Patent Document 1, a frequency filter in which two strip conductors are arranged in different layers of a dielectric substrate and vertically connected by electric field coupling has two strip conductors due to a manufacturing error. If the distance between the two strip conductors, that is, the distance between the two different layers in which the two strip conductors are arranged, varies, the coupling coefficient may fluctuate, and as a result, the filter characteristics may deteriorate.

The present invention is for solving the above-mentioned problems, and an object of the present invention is to provide a resonator coupling structure capable of suppressing fluctuations in the coupling coefficients of two resonators even if there is a manufacturing error. ..

The resonator coupling structure according to the present invention includes a plate-shaped insulator having a first layer and a second layer parallel to each other, a ground conductor having one surface arranged parallel to one surface of the insulator, and a first layer of the insulator. A first strip conductor that is arranged in one layer and has an open end at one end and operates as a first resonator, and a first strip conductor that is arranged in the first layer of an insulator and is arranged at a position where a gap is provided from one end of the first strip conductor. The first floating conductor is provided, and the second strip conductor which is arranged in the second layer of the insulator and has an open end and operates as a second resonator. One end of the two-strip conductor is arranged so as to be close to each other, and the first floating conductor is arranged so as to overlap the second strip conductor in a direction orthogonal to the second layer.

According to the present invention, fluctuations in the coupling coefficients of the two resonators can be suppressed even if there is a manufacturing error.

FIG. 1A is a diagram showing an example of an exploded view of the resonator coupling structure according to the first embodiment. FIG. 1B is a diagram showing an example of a cross-sectional view of the resonator coupling structure according to the first embodiment as viewed from the direction of arrow X shown in FIG. 1A. FIG. 2 is a circuit diagram showing an example of an equivalent circuit of a coupled resonator in which two resonators are electrically coupled. FIG. 3A is a circuit diagram when the control surface of the equivalent circuit shown in FIG. 2 is an electric wall. FIG. 3B is a circuit diagram when the control surface of the equivalent circuit shown in FIG. 2 is a magnetic wall. FIG. 4 is a diagram showing an example of the calculation result of the coupling coefficient when the thickness between the first layer and the second layer fluctuates in the conventional structure. FIG. 5 is a diagram showing a capacitance configuration in the vicinity between both ends of the two resonators in the odd-mode resonance of the resonator coupling structure according to the first embodiment. FIG. 6 is a diagram showing an example of a calculation result of a coupling coefficient when the thickness between the first layer and the second layer fluctuates in the resonator coupling structure according to the first embodiment. FIG. 7A is a diagram showing an example of an exploded view in a modified example of the resonator coupling structure according to the first embodiment. FIG. 7B is a diagram showing an example of an arrow view of the resonator coupling structure shown in FIG. 7A as viewed from the direction of arrow Y shown in FIG. 7A. FIG. 7C is a diagram showing an example of a cross-sectional view of the resonator coupling structure shown in FIG. 7A as viewed from the direction of arrow X shown in FIG. 7A. FIG. 8A is a diagram showing an example of an exploded view in a modified example of the resonator coupling structure according to the first embodiment. FIG. 8B is a diagram showing an example of an arrow view of the resonator coupling structure shown in FIG. 8A as viewed from the direction of arrow Y shown in FIG. 8A. FIG. 9A is a diagram showing an example of an exploded view in a modified example of the resonator coupling structure according to the first embodiment. FIG. 9B is a diagram showing an example of an arrow view of the resonator coupling structure shown in FIG. 9A as viewed from the direction of arrow Y shown in FIG. 9A. FIG. 10A is a diagram showing an example of an exploded view of the resonator coupling structure according to the second embodiment. FIG. 10B is a diagram showing an example of a cross-sectional view of the resonator coupling structure according to the second embodiment as viewed from the X direction shown in FIG. 10A. FIG. 11 is a diagram showing an example of an exploded view of the resonator coupling structure according to the third embodiment. FIG. 12A is a diagram showing an example of an exploded view of the frequency filter according to the fourth embodiment. FIG. 12B is an arrow view of the frequency filter according to the fourth embodiment as viewed from the Y direction shown in FIG. 12A. FIG. 13A is a diagram showing an example of an exploded view of the frequency filter according to the modified example of the fourth embodiment. FIG. 13B is an arrow view of the frequency filter according to the modified example of the fourth embodiment as viewed from the Y direction shown in FIG. 13A. FIG. 14A is a diagram showing an example of an exploded view of the frequency filter according to the fifth embodiment. FIG. 14B is an arrow view of the frequency filter according to the fifth embodiment as viewed from the Y direction shown in FIG. 14A.

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

Embodiment 1.
The resonator coupling structure 100 according to the first embodiment will be described with reference to FIGS. 1 to 9.
FIG. 1A is a diagram showing an example of an exploded view of the resonator coupling structure 100 according to the first embodiment.
FIG. 1B is a cross-sectional view of the resonator coupling structure 100 according to the first embodiment as viewed from the X direction shown in FIG. 1A, showing an example of a cross-sectional view at a position where the strip conductor 4a and the strip conductor 4b are present. Is.
The main part of the resonator coupling structure 100 according to the first embodiment is composed of an insulator 1, ground conductors 2a and 2b, connecting conductors 3, strip conductors 4a, strip conductors 4b, floating conductors 5a, and floating conductors 5b. ..

The insulator 1 has a plate-like shape.
The insulator 1 has a first layer 1a and a second layer 1b parallel to each other inside the insulator 1.

One surface of the ground conductor 2a is arranged parallel to one surface of the insulator 1.
In the ground conductor 2a shown in FIG. 1A or FIG. 1B, one surface of the ground conductor 2a and one surface of the insulator 1 are arranged so as to face each other so that one surface of the ground conductor 2a becomes one surface of the insulator 1. They are arranged in parallel.
One surface of the ground conductor 2b is arranged parallel to the other surface of the insulator 1.
The ground conductor 2b shown in FIG. 1A or FIG. 1B is a ground conductor by arranging one surface of the ground conductor 2b and the other surface of the insulator 1 facing one surface of the insulator 1 so as to face each other. One surface of 2b is arranged parallel to the other surface of the insulator 1.
It is assumed that both the ground conductor 2a and the ground conductor 2b according to the first embodiment are the ground planes of the circuit.
The connecting conductor 3 is connected to the ground conductor 2a and the ground conductor 2b.
That is, the ground conductor 2a and the ground conductor 2b are connected via the connecting conductor 3.
The term "parallel" here is not limited to strict parallelism, but includes substantially parallelism.

The strip conductor 4a is arranged on the first layer 1a of the insulator 1.
The strip conductor 4a operates as a resonator.
That is, the strip conductor 4a is a first strip conductor that operates as a first resonator.
One end of the strip conductor 4a is an open end.
The other end of the strip conductor 4a according to the first embodiment is connected to the connecting conductor 3, and the strip conductor 4a is connected to the ground conductor 2a and the ground conductor 2b via the connecting conductor 3.
If one end of the strip conductor is electrically open and the other end of the strip conductor is short-circuited to ground by some conductive means, the strip conductor must be stripped in order for the strip conductor to act as a resonator. The length of the conductor in the longitudinal direction needs to be an odd multiple of about λeff / 4.
However, λeff indicates the effective wavelength at the operating frequency. Note that λeff / 4 referred to here is not limited to strict λeff / 4, but includes substantially λeff / 4. In the following description, λeff / 4 will be described as including substantially λeff / 4.
Therefore, in the strip conductor 4a according to the first embodiment, it is assumed that the length of the strip conductor 4a in the longitudinal direction is an odd multiple of λeff / 4.

The strip conductor 4b is arranged on the second layer 1b of the insulator 1.
The strip conductor 4b operates as a resonator.
That is, the strip conductor 4b is a second strip conductor that operates as a second resonator.
One end of the strip conductor 4b is an open end.
The other end of the strip conductor 4b is connected to the connecting conductor 3, and the strip conductor 4a is connected to the ground conductor 2a and the ground conductor 2b via the connecting conductor 3.
Therefore, it is assumed that the length of the strip conductor 4b according to the first embodiment in the longitudinal direction is an odd multiple of λeff / 4.

The strip conductor 4a or the strip conductor 4b may have one end and the other end of the strip conductor 4a, or one end and the other end of the strip conductor 4b both electrically open ends.
In order for the strip conductor to operate as a resonator if both one end and the other end of the strip conductor are open ends, or if both one end and the other end of the strip conductor are short-circuited to ground by some conductive means. The strip conductor needs to have a longitudinal length of the strip conductor that is an integral multiple of λeff / 2.
Therefore, when both one end and the other end of the strip conductor 4a are open ends, the length of the strip conductor 4a in the longitudinal direction needs to be an integral multiple of λeff / 2. Further, when both one end and the other end of the strip conductor 4b are open ends, the length of the strip conductor 4b in the longitudinal direction needs to be an integral multiple of λeff / 2.
Note that λeff / 2 referred to here is not limited to strict λeff / 2, but includes approximately λeff / 2.

The floating conductor 5a is arranged on the first layer 1a of the insulator 1.
The floating conductor 5a is arranged at a position where a gap is provided from one end of the strip conductor 4a.
That is, the floating conductor 5a is the first floating conductor.
The floating conductor 5b is arranged on the second layer 1b of the insulator 1.
The floating conductor 5b is arranged at a position where a gap is provided from one end of the strip conductor 4b.
That is, the floating conductor 5b is the second floating conductor.

One end of the strip conductor 4a and one end of the strip conductor 4b are arranged so as to be close to each other.
The floating conductor 5b is arranged so as to overlap the strip conductor 4a in the direction orthogonal to the first layer 1a.
The floating conductor 5a is arranged so as to overlap the strip conductor 4b in the direction orthogonal to the second layer 1b.
The term "orthogonal" as used herein is not limited to strict orthogonality, but includes substantially orthogonality.

The operation of the resonator coupling structure (hereinafter referred to as “conventional structure”) excluding the floating conductor 5a and the floating conductor 5b from the resonator coupling structure 100 according to the first embodiment will be described.
Both the strip conductor 4a and the strip conductor 4b in the conventional structure have an open end at one end, and the other end is short-circuited to the ground conductor 2a and the ground conductor 2b via the connecting conductor 3.
Since both the strip conductor 4a and the strip conductor 4b in the conventional structure operate as a resonator, the lengths of the strip conductor 4a and the strip conductor 4b in the longitudinal direction are both λeff / 4. That is, both the strip conductor 4a and the strip conductor 4b in the conventional structure operate as a 1/4 wavelength resonator.
Further, in the conventional structure, both the strip conductor 4a and the strip conductor 4b are close to each other at both ends, which are open ends, and are coupled to each other by electric field coupling. That is, in the conventional structure, the resonator composed of the strip conductor 4a and the resonator composed of the strip conductor 4b operate as a coupled resonator in which an electric field is coupled.

As in the conventional structure described above, the equivalent circuit of a coupled resonator in which two resonators are electrically coupled is represented as a circuit in which capacitors in two resonators each having an inductor and a capacitor are coupled by a mutual capacitor. ..
FIG. 2 is a circuit diagram showing an example of an equivalent circuit of a coupled resonator in which two resonators are electrically coupled.
The equivalent circuit shown in FIG. 2 is a circuit in which two resonators, each having an inductance L and a capacitance C, are coupled via a mutual capacitance Cm.
The equivalent circuit shown in FIG. 2 is symmetrical with respect to the central alternate long and short dash line.
The resonance angular frequency ω ₀ of each resonator is given by Eq. (1).

The resonance angular frequency in the two resonance modes of the coupled resonator in which the two resonators are electrically coupled can be easily obtained by the even-odd mode analysis.
FIG. 3A is a circuit diagram when the control surface of the equivalent circuit shown in FIG. 2 is an electric wall.
FIG. 3B is a circuit diagram when the control surface of the equivalent circuit shown in FIG. 2 is a magnetic wall.

式（２）より、奇モード共振における共振角周波数ω_ｏｄｄは、相互キャパシタンスＣ_ｍの寄与により、式（１）で表される共振器単体における共振角周波数ω_０と比べて低くなることがわかる。When the control surface of the equivalent circuit shown in FIG. 2 is an electric wall, the combined capacitance is obtained by the sum of _{the capacitance C, the mutual capacitance −C m,} and the mutual capacitance 2 C _m. That is, when the control surface of the equivalent circuit shown in FIG. 2 is an electric wall, the combined capacitance is “CC _m + 2 C _m ”. Therefore, when the control surface of the equivalent circuit shown in FIG. 2 is an electric wall, that is, the resonance angular frequency ω _odd in the odd-mode resonance of the coupled resonator in which the two resonators are electrically coupled is expressed by Eq. (2). Can be done.

From equation (2), the resonance angular frequency omega _odd in the odd mode resonance, the contribution of the mutual capacitance C _m, it is found to be lower than the resonance angular frequency omega ₀ in the resonator itself represented by the formula (1) ..

式（２）より、偶モード共振における共振角周波数ω_ｅｖｅｎは、相互キャパシタンスＣ_ｍの寄与により、式（１）で表される共振器単体における共振角周波数ω_０と比べて高くなることがわかる。On the other hand, when the control surface of the equivalent circuit shown in FIG. 2 is a magnetic wall, the combined capacitance is obtained by the sum of _{the capacitance C and the mutual capacitance −C m.} That is, the combined capacitance when the control surface of the equivalent circuit shown in FIG. 2 is a magnetic wall is “CC _m ”. Therefore, when the control surface of the equivalent circuit shown in FIG. 2 is a magnetic wall, that is, the resonance angular frequency ω _even in the even-mode resonance of the coupled resonator in which the two resonators are electrically coupled is expressed by the equation (3). Can be done.

From equation (2), the resonance angular frequency omega _{the even} in the even mode resonance, the contribution of the mutual capacitance C _m, it can be seen that is higher than the resonance angular frequency omega ₀ in the resonator itself represented by the formula (1) ..

Further, the coupling coefficient between the two resonators can be approximately calculated by the equation (4) using the resonance angular frequency ω _{odd in the odd} mode resonance and the resonance angular frequency ω _{even in the even mode resonance.}

The resonance angular frequency in the actual conventional structure, that is, the resonator coupling structure excluding the floating conductor 5a and the floating conductor 5b from the resonator coupling structure 100 according to the first embodiment shown in FIG. 1, is expressed in the equivalent circuit of the conventional structure. It is different from the ideal resonance angular frequency shown by (1) to (3). That is, since the resonance angular frequency in the actual conventional structure is an electric field coupling of two resonators, the resonance angular frequency ω _{odd in the odd-} mode resonance and the resonance angular frequency in the even-mode resonance depend on the actual conventional structure. ω _even changes respectively.
In the actual conventional structure, the electric field is concentrated in the vicinity of both adjacent ends, which are both open ends, at the time of odd-mode resonance. Therefore, the resonance angular frequency ω _odd in the odd-mode resonance is significantly lower than the resonance angular frequency ω _{0 in the resonator alone.}
On the other hand, in the actual conventional structure, since the two resonators have the same potential at the time of even mode resonance, the electric field does not concentrate in the vicinity of both ends of the two resonators. Therefore, the resonance angular frequency ω _even in the even-mode resonance is slightly higher than the resonance angular frequency ω _{0 in the resonator alone.}

ただし、ε_０は真空の誘電率、ε_ｒは２つの電極により挟まれた部材の比誘電率、Ｓは２つの電極における相対する部位の面積、及び、ｄは２つの電極の間隔である。The conventional structure, when the odd mode resonance, since the two field in the vicinity of both end of the resonator is concentrated, the variation of the capacitance C _p in the vicinity between both end of the two resonators in odd mode resonance, the coupling coefficient It becomes a variable factor of. Capacitance in the vicinity between both end of the two resonators in the actual conventional structure, mainly composed of a strip conductor 4a, the capacitance C _p is a parallel plate capacitance due and the strip conductor 4b. Capacitance C _p is generated by applying an AC voltage between two electrodes arranged through a minute void. The capacitance C _p is expressed by the equation (5).

However, ε ₀ is the permittivity of the vacuum, ε _r is the relative permittivity of the member sandwiched between the two electrodes, S is the area of the opposing portions of the two electrodes, and d is the distance between the two electrodes.

In the actual conventional structure, since the two electrodes are composed of the strip conductor 4a and the strip conductor 4b, the areas S of the opposing portions of the two electrodes are orthogonal to the extending direction of the strip conductor 4a and the strip conductor 4b. It is the area of the overlapping part in the direction of Further, the distance d between the two electrodes is the thickness between the first layer 1a in which the strip conductor 4a is arranged and the second layer 1b in which the strip conductor 4b is arranged. Therefore, by the variation in the thickness between the first layer 1a and the second layer 1b, the actual conventional structure, the capacitance C _p in the vicinity between both end of the two resonators in odd mode resonance fluctuates ..

FIG. 4 is a diagram showing an example of the calculation result of the coupling coefficient when the thickness between the first layer 1a and the second layer 1b fluctuates in the conventional structure. In FIG. 4, the horizontal axis represents the thickness between the normalized first layer 1a and the second layer 1b, and the vertical axis represents the calculated coupling coefficient.
The horizontal axis of FIG. 4 shows the ratio of the actual thickness between the first layer 1a and the second layer 1b to the desired thickness between the first layer 1a and the second layer 1b. For example, 1.00 on the horizontal axis of FIG. 4 is the case where the thickness between the first layer 1a and the second layer 1b is a desired thickness, and 1.20 on the horizontal axis of FIG. 4 is the first layer. The case where the thickness between 1a and the second layer 1b is 1.2 times the desired thickness is shown. As shown in FIG. 4, the coupling coefficient varies almost linearly with respect to the thickness between the normalized first layer 1a and the second layer 1b, and the slope becomes −0.0524. It can be confirmed that there is.

The operation of the resonator coupling structure 100 according to the first embodiment will be described.
As shown in FIG. 1, the resonator coupling structure 100 has a floating conductor 5a arranged in the first layer 1a and a floating conductor 5b arranged in the second layer 1b.

_{FIG. 5 is a diagram showing a configuration of a capacitance C b} in the vicinity between both ends of two resonators in an odd mode resonance of the resonator coupling structure 100 according to the first embodiment.
In resonator coupling structure 100, the capacitance C _b in the vicinity between both end of the two resonators in odd mode resonance, the floating conductor 5a and the strip conductor 4a and the strip conductor 4b and are directly without any floating conductor 5b It is composed of two types of capacitances, a capacitance C _{p at the time of coupling and a capacitance C f at} the time of indirectly coupling the strip conductor 4a and the strip conductor 4b via the floating conductor 5a or the floating conductor 5b.
Further, the capacitance C _{f is the capacitance C g} due to the gap coupling between one end of the strip conductor 4a and the floating conductor 5a and the capacitance C which is the parallel plate capacitance between the floating conductor 5a and the strip conductor 4b. the capacitance C _d between the combined capacitance in which a _d are connected in series, and a capacitance C _g by gap junctions through a space between the end and the floating conductor 5b of the strip conductor 4b, the floating conductor 5b and the strip conductors 4a Consists of a combined capacitance connected in series.

The capacitance C _p when the strip conductor 4a and the strip conductor 4b without passing through any of the floating conductor 5a and the floating conductor 5b is bonded directly, as in the conventional structure, between the first layer 1a and the second layer 1b It fluctuates greatly due to the variation in the thickness of. _{On the other hand, the capacitance C f} when the strip conductor 4a and the strip conductor 4b are indirectly coupled via the floating conductor 5a or the floating conductor 5b is composed of a combined capacitance in which the capacitance C _g and the capacitance C _d are connected in series. , The capacitance C _f is represented by the equation (6).

Generally, it arranged in the same layer, between the strip conductors 4a and a floating conductor 5a, or the capacitance C _g by gap junctions through a gap between the strip conductor 4b and the floating conductor 5b is floating conductor 5a and the strip between the conductors 4b, or small compared to the capacitance C _d between the floating conductors 5b and the strip conductor 4a. That is, the relationship between _{the capacitance C g} and the capacitance C _d can be expressed as _{C g} << C _d. Therefore, the capacitance C _f is approximated as shown in the equation (7), and the capacitance C _f is dominated by the capacitance C _g.

Since the capacitance _Cg is due to a gap junction between the strip conductor 4a and the floating conductor 5a or between the strip conductor 4b and the floating conductor 5b arranged in the same layer, the first capacitance Cg is formed. There is little variation due to variations in the thickness between the layers 1a and the second layer 1b. Therefore, the capacitance C _f also has little variation due to variations in the thickness between the first layer 1a and the second layer 1b.
In resonator coupling structure 100, the capacitance C _b in the vicinity between both end of the two resonators in odd mode resonance, the floating conductor 5a and the strip conductor 4a and the strip conductor 4b and are directly without any floating conductor 5b Because the capacitance C _{p at the time of coupling and the capacitance C f at} the time of indirectly coupling the strip conductor 4a and the strip conductor 4b via the floating conductor 5a or the floating conductor 5b are the capacitances synthesized by parallel connection. , Capacitance C _b is represented by the equation (8).

In the formula (8), the first term on the right side is less susceptible to the variation in thickness between the first layer 1a and the second layer 1b as described above, while the second term on the right side is less affected. Is susceptible to variations in thickness between the first layer 1a and the second layer 1b, as in the conventional structure. Accordingly, the resonator coupling structure 100, the capacitance C _b in the vicinity between both end of the two resonators in odd mode resonance, the larger the ratio of capacitance C _g, a first layer 1a and the second layer 1b It is less susceptible to the effects of variations in thickness between.

FIG. 6 is a diagram showing an example of a calculation result of a coupling coefficient when the thickness between the first layer 1a and the second layer 1b fluctuates in the resonator coupling structure 100 according to the first embodiment. In FIG. 6, similarly to FIG. 4, the horizontal axis represents the thickness between the normalized first layer 1a and the second layer 1b, and the vertical axis represents the calculated coupling coefficient. As shown in FIG. 6, the coupling coefficient changes substantially linearly with respect to the thickness between the normalized first layer 1a and the second layer 1b, and the slope becomes −0.0253. It can be confirmed that there is. Comparing the variation of the coupling coefficient in the conventional structure shown in FIG. 4 with the variation of the coupling coefficient in the resonator coupling structure 100 shown in FIG. 6, the resonator coupling structure 100 has the first layer 1a and the second layer 1b. It can be confirmed that the fluctuation of the coupling coefficient due to the variation in the thickness between the two is suppressed to about half.
That is, the resonator coupling structure 100 according to the first embodiment includes the floating conductor 5a and the floating conductor 5b, so that the thickness between the first layer 1a and the second layer 1b varies, so that the coupling coefficient becomes different. The variation can be suppressed by comparing it with the variation of the coupling coefficient in the conventional structure.

The resonator coupling structure 100 includes the floating conductor 5a and the floating conductor 5b, so that the variation in the coupling coefficient due to the variation in the thickness between the first layer 1a and the second layer 1b can be suppressed by the coupling coefficient in the conventional structure. As long as it can be suppressed as compared with the fluctuation of, the configuration is not limited to the configuration shown in FIG.
For example, in the resonator coupling structure 100, the other end of the strip conductor 4a, one end of which operates as a resonator is an open end, is connected to an input terminal for inputting a high frequency signal, and one end of the resonator coupling structure 100 operates as a resonator. The other end of the strip conductor 4b, which is an open end, may be connected to an output terminal for outputting a high frequency signal.

Further, the resonator coupling structure 100 includes a floating conductor 5a arranged in the first layer 1a in which the strip conductor 4a is arranged and a floating conductor 5b arranged in the second layer 1b in which the strip conductor 4b is arranged. Although an example is shown, the resonator coupling structure 100 may include either a floating conductor 5a or a floating conductor 5b.
In the resonator coupling structure 100, the resonator coupling structure provided with either the floating conductor 5a or the floating conductor 5b has a variation in thickness between the first layer 1a and the second layer 1b, similarly to the resonator coupling structure 100. The fluctuation of the coupling coefficient due to the occurrence can be suppressed as compared with the fluctuation of the coupling coefficient in the conventional structure.

Further, the resonator coupling structure 100 may be deformed into the configuration shown in FIG. 7 or 8, for example.
FIG. 7A is a diagram showing an example of an exploded view of a modified example of the resonator coupling structure 100 according to the first embodiment.
FIG. 7B is a diagram showing an example of an arrow view of the resonator coupling structure 100 shown in FIG. 7A as viewed from the direction of arrow Y shown in FIG. 7A. Note that FIG. 7B is a view in which the insulator 1 and the ground conductor 2a are transparent.
FIG. 7C is a cross-sectional view of the resonator coupling structure 100 shown in FIG. 7A as viewed from the direction of arrow X shown in FIG. 7A, and is a cross-sectional view at a position where both ends of the strip conductor 4a and the strip conductor 4b are present. It is a figure which shows an example.
FIG. 8A is a diagram showing an example of an exploded view in a modified example of the resonator coupling structure 100 according to the first embodiment.
FIG. 8B is a diagram showing an example of an arrow view of the resonator coupling structure 100 shown in FIG. 8A as viewed from the direction of arrow Y shown in FIG. 8A. Note that FIG. 8B is a view in which the insulator 1 and the ground conductor 2a are transparent.

In the resonator coupling structure 100 shown in FIG. 1, the longitudinal direction of the strip conductor 4a and the longitudinal direction of the strip conductor 4b are parallel, and the other end of the strip conductor 4a and the other end of the strip conductor 4b are the strip conductor 4a. Is arranged so that one end of the strip conductor 4b and one end of the strip conductor 4b are opposite to each other with respect to the adjacent position.
In the resonator coupling structure 100, for example, as shown in FIG. 7, the strip conductor 4a and the strip conductor 4b are arranged so that the other end of the strip conductor 4a and the other end of the strip conductor 4b are adjacent to each other. It may be deformed as described above.
The resonator coupling structure 100 may be arranged so that the strip conductor 4a and the strip conductor 4b are orthogonal to each other, for example, as shown in FIG.
Note that FIGS. 1, 7, and 8 are examples, and the arrangement of the strip conductor 4a, the strip conductor 4b, the floating conductor 5a, and the floating conductor 5b in the resonator coupling structure 100 is shown in FIGS. 1, 7, and FIG. The arrangement of the strip conductor 4a, the strip conductor 4b, the floating conductor 5a, and the floating conductor 5b shown in 8 is not limited to the arrangement.

Further, the resonator coupling structure 100 is an example in which the ground conductor 2a is arranged so as to be in contact with one surface of the insulator 1 and the ground conductor 2b is arranged so as to be in contact with the other surface of the insulator 1 facing one surface of the insulator 1. However, in the resonator coupling structure 100, the ground conductor 2a or the ground conductor 2b is parallel to the first layer 1a or the second layer 1b of the insulator 1, which is different from the first layer 1a and the second layer 1b. It may be arranged in a layer (not shown).

Further, the resonator coupling structure 100 shows an example in which two ground conductors 2a and a ground conductor 2b are arranged, but in the resonator coupling structure 100, either one of the ground conductor 2a or the ground conductor 2b is arranged. It may be a thing.

Further, although the resonator coupling structure 100 shows an example in which the conductor widths of the strip conductor 4a and the strip conductor 4b are uniform with respect to the length direction of the strip conductor 4a and the strip conductor 4b, the strip conductor 4a and the strip conductor 4b are shown. For example, as in a stepped impedance resonator, the conductor width of the strip conductor 4a or the strip conductor 4b changes stepwise or continuously depending on the position of the strip conductor 4a or the strip conductor 4b in the length direction. It may be a structure.

Further, the resonator coupling structure 100 may be deformed into the configuration shown in FIG. 9, for example.
FIG. 9A is a diagram showing an example of an exploded view of a modified example of the resonator coupling structure 100 according to the first embodiment.
FIG. 9B is a diagram showing an example of an arrow view of the resonator coupling structure 100 shown in FIG. 9A as viewed from the direction of arrow Y shown in FIG. 9A. Note that FIG. 9B is a view in which the insulator 1 and the ground conductor 2a are transparent.
In the resonator coupling structure 100 shown in FIG. 9, both ends of the strip conductor 4a and the strip conductor 4b, and both other ends of the strip conductor 4a and the strip conductor 4b are open ends, and one end and the other end of the strip conductor 4a, In addition, the floating conductor 5a and the floating conductor 5b are arranged at positions where gaps are provided from each of one end and the other end of the strip conductor 4b.
In the resonator coupling structure 100 shown in FIG. 9, since both ends of the strip conductor 4a and the strip conductor 4b and both other ends of the strip conductor 4a and the strip conductor 4b are open ends, the strip conductor 4a and the strip conductor 4b The length in the longitudinal direction is an integral multiple of λeff / 2.

Further, in the resonator coupling structure 100, one of two floating conductors 5a arranged at positions provided with gaps from one end and the other end of the strip conductor 4a is removed from the resonator coupling structure 100 shown in FIG. It may be a thing. Similarly, one of the two floating conductors 5b arranged at the positions where the gaps are provided may be removed from one end and the other end of the strip conductor 4b from the resonator coupling structure 100 shown in FIG. ..

As described above, the resonator coupling structure 100 includes a plate-shaped insulator 1 having a first layer 1a and a second layer 1b parallel to each other, and a ground conductor whose one surface is arranged parallel to one surface of the insulator 1. 2a and 2b, a strip conductor 4a which is a first strip conductor which is arranged in the first layer 1a of the insulator 1 and has an open end and operates as a first resonator, and a first layer 1a of the insulator 1. The floating conductor 5a, which is the first floating conductor, is arranged at a position where a gap is provided from one end of the strip conductor 4a, and the second layer 1b of the insulator 1, one end of which is an open end. A strip conductor 4b, which is a second strip conductor operating as a two resonators, is provided, one end of the strip conductor 4a and one end of the strip conductor 4b are arranged so as to be close to each other, and the floating conductor 5a is a second layer. It is arranged so as to overlap the strip conductor 4b in the direction orthogonal to 1b.

Further, the resonator coupling structure 100 includes a plate-shaped insulator 1 having a first layer 1a and a second layer 1b parallel to each other, and ground conductors 2a and 2b whose one surface is arranged parallel to one surface of the insulator 1. , The strip conductor 4a, which is a first strip conductor operating as a first resonator, which is arranged on the first layer 1a of the insulator 1 and has an open end at one end, and the first layer 1a of the insulator 1 are arranged. As a second resonator, which is a floating conductor 5a which is a first floating conductor arranged at a position where a gap is provided from one end of the strip conductor 4a, and a second resonator which is arranged in the second layer 1b of the insulator 1 and has an open end at one end. A strip conductor 4b, which is a second strip conductor that operates, and a floating conductor 5b, which is a second floating conductor arranged in the second layer 1b of the insulator 1 and at a position where a gap is provided from one end of the strip conductor 4b. , And one end of the strip conductor 4a and one end of the strip conductor 4b are arranged so as to be close to each other, and the floating conductor 5b is arranged so as to overlap the strip conductor 4a in a direction orthogonal to the first layer 1a. The floating conductor 5a may be arranged so as to overlap the strip conductor 4b in a direction orthogonal to the second layer 1b.

With this configuration, the resonator coupling structure 100 can suppress fluctuations in the coupling coefficients of the two resonators even if there is a manufacturing error.

Embodiment 2.
The resonator coupling structure 100a according to the second embodiment will be described with reference to FIG.
FIG. 10A is a diagram showing an example of an exploded view of the resonator coupling structure 100a according to the second embodiment.
FIG. 10B is a diagram showing an example of a cross-sectional view of the resonator coupling structure 100a according to the second embodiment as viewed from the X direction shown in FIG. 10A.
In the resonator coupling structure 100a according to the second embodiment, the insulator 1 of the resonator coupling structure 100 according to the first embodiment and the ground conductors 2a and 2b and the connecting conductor 3 are the insulator 1 and the ground conductor housing, respectively. It was changed to body 6.
That is, the main part of the resonator coupling structure 100a according to the second embodiment is composed of an insulator 1, a ground conductor housing 6, a strip conductor 4a, a strip conductor 4b, a floating conductor 5a, and a floating conductor 5b.

The insulator 1 has a plate-like shape.
The insulator 1 has a first layer 1a and a second layer 1b parallel to each other.
The first layer 1a in the insulator 1 is one surface of the insulator 1, and the second layer 1b in the insulator 1 is the other surface of the insulator 1 facing one surface of the insulator 1.

The ground conductor housing 6 is a housing of a resonator coupling structure 100a composed of a ground conductor.
The ground conductor housing 6 is arranged at a position where a gap is provided from the first layer 1a so that a part of the ground conductor housing 6 is parallel to one surface of the insulator 1, that is, the first layer 1a. Further, the ground conductor housing 6 is arranged at a position where a gap is provided from the second layer 1b so that a part of the ground conductor housing 6 is parallel to the other surface of the insulator 1, that is, the second layer 1b. Will be done.
The ground conductor housing 6 according to the second embodiment is assumed to be the ground surface of the circuit.

The strip conductor 4a is arranged on the first layer 1a of the insulator 1.
The strip conductor 4a operates as a resonator.
Both one end and the other end of the strip conductor 4a are open ends.
The floating conductor 5a is arranged at a position where a gap is provided in the first layer 1a of the insulator 1 from one end or the other end of the strip conductor 4a. As an example, the resonator coupling structure 100a according to the second embodiment includes two floating conductors 5a arranged at positions where gaps are provided from one end and the other end of the strip conductor 4a as shown in FIG. It is explained as.

The strip conductor 4b is arranged on the second layer 1b of the insulator 1.
The strip conductor 4b operates as a resonator.
Both one end and the other end of the strip conductor 4b are open ends.
The floating conductor 5b is arranged at a position where a gap is provided in the second layer 1b of the insulator 1 from one end or the other end of the strip conductor 4b. As an example, the resonator coupling structure 100a according to the second embodiment includes two floating conductors 5b arranged at positions where gaps are provided from one end and the other end of the strip conductor 4b as shown in FIG. It is explained as.

One end of the strip conductor 4a and one end of the strip conductor 4b are arranged so as to be close to each other.
The other end of the strip conductor 4a and the other end of the strip conductor 4b are arranged so as to be close to each other.
The floating conductor 5b is arranged so as to overlap the strip conductor 4a in the direction orthogonal to the first layer 1a.
The floating conductor 5a is arranged so as to overlap the strip conductor 4b in the direction orthogonal to the second layer 1b.
Both ends and both ends of the strip conductor 4a and the strip conductor 4b are open ends. Since both the strip conductor 4a and the strip conductor 4b operate as a resonator, the lengths of the strip conductor 4a and the strip conductor 4b in the longitudinal direction are both λeff / 2. That is, both the strip conductor 4a and the strip conductor 4b in the resonator coupling structure 100a operate as a 1/2 wavelength resonator.

That is, the resonator coupling structure 100a according to the second embodiment illustrated in FIG. 10 includes the insulator 1 of the resonator coupling structure 100 according to the first embodiment exemplified in FIG. 9, the ground conductors 2a and 2b, and the ground conductors 2a and 2b. The connecting conductor 3 is changed to an insulator 1 and a ground conductor housing 6, respectively.

The operation of the resonator coupling structure 100a according to the second embodiment will be described.
In the second embodiment, the description that overlaps with the description of the resonator coupling structure 100 according to the first embodiment will be omitted.

In general, the dielectric loss in air is negligibly small compared to the dielectric loss in a dielectric substrate. For example, a transmission line that suppresses a dielectric loss per unit length by adopting a hollow structure in a transmission line that propagates a high-frequency signal, such as a suspended line structure, is known.
In the resonator coupling structure 100a according to the second embodiment, the ground conductor 2a and the ground conductor 2b in the resonator coupling structure 100 according to the first embodiment are changed to the ground conductor housing 6, and the ground conductor housing 6 is an insulator. It is arranged so as to surround the outside of 1. That is, the ground conductor constituting the ground conductor housing 6 is arranged at a position separated from the surface of the insulator 1 on which the strip conductor 4a or the strip conductor 4b is arranged in a direction orthogonal to the surface.
With this arrangement, a hollow structure is formed between the strip conductor 4a and the ground conductor housing 6 and between the strip conductor 4b and the ground conductor housing 6. Due to the hollow structure, the resonator coupling structure 100a according to the second embodiment can have a smaller dielectric loss than the resonator coupling structure 100 according to the first embodiment.

Further, since the resonator coupling structure 100a of the second embodiment can reduce the dielectric loss as compared with the resonator coupling structure 100 according to the first embodiment, a larger coupling coefficient can be obtained. Further, in the resonator coupling structure 100a of the second embodiment, the distance between the strip conductor 4a or the strip conductor 4b and the ground conductor housing 6 composed of the ground conductor is not limited by the thickness of the insulator 1. , Can be decided arbitrarily. Therefore, the resonator coupling structure 100a of the second embodiment includes the distance between the strip conductor 4a and the strip conductor 4b, and the ground conductor housing 6 composed of the strip conductor 4a or the strip conductor 4b and the ground conductor. It can be configured to increase the distance between the strip conductor 4a and the strip conductor 4b, and the withstand power at the open end of the strip conductor 4a or the strip conductor 4b can be improved as compared with the resonator coupling structure 100 of the first embodiment. It will be possible.
From the above, the resonator coupling structure 100a according to the second embodiment suppresses fluctuations in the coupling coefficient due to variations in the thickness between the first layer 1a and the second layer 1b, that is, the thickness of the insulator 1. At the same time, it enables low loss and high power resistance of the resonator.

Embodiment 3.
The resonator coupling structure 100b according to the third embodiment will be described with reference to FIG.
FIG. 11 is a diagram showing an example of an exploded view of the resonator coupling structure 100b according to the third embodiment.
The resonator coupling structure 100b according to the third embodiment is a first floating conductor group in which the floating conductor 5a and the floating conductor 5b of the resonator coupling structure 100 according to the first embodiment are each composed of a plurality of floating conductors 5a. The floating conductor group 7a is changed to the floating conductor group 7b, which is a second floating conductor group composed of a plurality of floating conductors 5b.
That is, the main part of the resonator coupling structure 100b according to the third embodiment is composed of an insulator 1, a ground conductor housing 6, a strip conductor 4a, a strip conductor 4b, a floating conductor group 7a, and a floating conductor group 7b. ..
In the configuration of the resonator coupling structure 100b according to the third embodiment, the same configuration as the resonator coupling structure 100 according to the first embodiment is designated by the same reference numerals and duplicated description will be omitted. That is, the description of the configuration of FIG. 11 having the same reference numerals as those shown in FIGS. 1A or 1B will be omitted.

The strip conductor 4a is arranged on the first layer 1a of the insulator 1.
The strip conductor 4a operates as a resonator.
One end of the strip conductor 4a is an open end.
The other end of the strip conductor 4a is connected to the connecting conductor 3, and the strip conductor 4a is connected to the ground conductor 2a and the ground conductor 2b via the connecting conductor 3.
The floating conductor group 7a is composed of a plurality of floating conductors 5a, and the floating conductor group 7a is arranged at a position where a gap is provided from one end of the strip conductor 4a in the first layer 1a of the insulator 1.
The length of the long side of the floating conductors 5a of the plurality of floating conductors 5a is λeff / 4 or less.

The strip conductor 4b is arranged on the second layer 1b of the insulator 1.
The strip conductor 4b operates as a resonator.
One end of the strip conductor 4b is an open end.
The other end of the strip conductor 4b is connected to the connecting conductor 3, and the strip conductor 4b is connected to the ground conductor 2a and the ground conductor 2b via the connecting conductor 3.
The floating conductor group 7b is composed of a plurality of floating conductors 5b, and the floating conductor group 7b is arranged at a position where a gap is provided from one end of the strip conductor 4b in the second layer 1b of the insulator 1.
The length of the long side of the floating conductors 5b of the plurality of floating conductors 5b is λeff / 4 or less.

One end of the strip conductor 4a and one end of the strip conductor 4b are arranged so as to be close to each other.
The floating conductor group 7b, that is, the plurality of floating conductors 5b are arranged so as to overlap the strip conductor 4a in the direction orthogonal to the first layer 1a.
The floating conductor group 7a, that is, the plurality of floating conductors 5a are arranged so as to overlap the strip conductor 4b in the direction orthogonal to the second layer 1b.

Both ends of the strip conductor 4a and the strip conductor 4b are open ends, and both other ends of the strip conductor 4a and the strip conductor 4b are short-circuited with the ground conductor 2a or the ground conductor 2b. Since both the strip conductor 4a and the strip conductor 4b operate as a resonator, the lengths of the strip conductor 4a and the strip conductor 4b in the longitudinal direction are both λeff / 4 or an odd multiple of λeff / 4. .. That is, the strip conductor 4a and the strip conductor 4b in the resonator coupling structure 100b both operate as a 1/4 wavelength resonator.

The operation of the resonator coupling structure 100b according to the third embodiment will be described.
It should be noted that the description of the content that overlaps with the content described in the previous embodiments will be omitted.

In general, it is known that a resonator composed of a distributed constant line such as a strip conductor resonates at approximately an integral multiple of the resonance frequency in the resonator or approximately an odd multiple of the resonance frequency in the resonator.
For example, in a resonator in which the length of the strip conductor in the longitudinal direction is λeff / 2 and both ends of the strip conductor are open ends, the length in the longitudinal direction is m times λeff / 2 (m is). It resonates at a frequency that becomes a natural number). Similarly, a resonator whose longitudinal length of the strip conductor is λeff / 4 and whose one end of the strip conductor is an open end and whose other end is short-circuited to the ground has a longitudinal length of λeff. It resonates at a frequency that is n times 4 (n is a positive odd number). In the above-mentioned two resonators, the resonance mode in which m = 1 or n = 1 is called a fundamental resonance mode, and the resonance mode in which m> 1 or n> 1 is called a higher-order resonance mode.

A frequency filter in which a plurality of resonators are electrically coupled has a problem that the spurious characteristics of the frequency filter deteriorate in the higher-order resonance mode. For example, the minimum m for which m> 1 is m = 2, and the minimum n for which n> 1 is n = 3, so that the frequency is approximately twice or three times higher than the frequency band used. The next resonance occurs.
On the other hand, in the resonator coupling structure 100 according to the first embodiment or the resonator coupling structure 100a according to the second embodiment, the floating conductor 5a or the floating conductor 5b is the length of the long side of the floating conductor 5a or the floating conductor 5b. However, it operates as a resonator at a frequency of about λeff / 2 or m times λeff / 2. As a result, the spurious characteristics of the frequency filter having the resonator coupling structure 100 according to the first embodiment or the resonator coupling structure 100a according to the second embodiment may deteriorate.

In the resonator coupling structure 100 according to the first embodiment or the resonator coupling structure 100a according to the second embodiment, the lengths of the long sides of the floating conductor 5a and the floating conductor 5b are set to λeff / 4 or less. It is possible to prevent the spurious characteristics of the frequency filter from being deteriorated.
However, if it is limited to the length of the long side of the floating conductor 5a or floating conductor 5b λeff / 4 below, the magnitude relation of capacitances C _g and the capacitance C _g is, Cg as described in the first embodiment <<Cd may not be obtained in some cases.
The resonator coupling structure 100b according to the third embodiment has a plurality of floating conductors 5a in which the length of the long side of the floating conductor 5a or the length of all sides of the floating conductor 5a is λeff / 4 or less at the operating frequency. The floating conductor group 7a composed of the above, or the length of the long side of the floating conductor 5b, or the length of all the sides of the floating conductor 5b is λeff / 4 or less at the operating frequency. The floating conductor group 7b was provided.

With this configuration, the resonator coupling structure 100b according to the third embodiment has a variation in thickness between the first layer 1a and the second layer 1b while suppressing deterioration of spurious characteristics. The variation of the coupling coefficient can be suppressed by comparing with the variation of the coupling coefficient in the conventional structure.

Embodiment 4.
The frequency filter 200 according to the fourth embodiment will be described with reference to FIG.
FIG. 12A is a diagram showing an example of an exploded view of the frequency filter 200 according to the fourth embodiment.
FIG. 12B is an arrow view of the frequency filter 200 according to the fourth embodiment as viewed from the Y direction shown in FIG. 12A. Note that FIG. 12B is a view in which the insulator 1 and the ground conductor 2a are transparent.
The frequency filter 200 shown in FIG. 12 includes an insulator 1, a ground conductor 2a, a ground conductor 2b, a connecting conductor 3, an input terminal 8a, an output terminal 8b, an input line 9a, an output line 9b, and a strip conductor 10a, 10b, 10c, 10d. , And floating conductors 11a, 11b, 11c, 11d.
In the configuration of the frequency filter 200 according to the fourth embodiment, the same configuration as the resonator coupling structures 100, 100a, 100b described in the previous embodiments will be omitted.

Hereinafter, description will be made with reference to FIG.
The insulator 1 has a plate-like shape.
The insulator 1 has a first layer 1a and a second layer 1b parallel to each other inside the insulator 1.
The input terminal 8a is a terminal for inputting a high frequency signal.
The output terminal 8b is a terminal for outputting a high frequency signal.
The input line 9a is a line for transmitting a high frequency signal received by the input terminal 8a from the input terminal 8a to the strip conductor 10a.
The output line 9b is a line for transmitting a high frequency signal output from the output terminal 8b from the strip conductor 10d to the output terminal 8b.

Each of the strip conductors 10a, 10b, 10c, and 10d has an open end at one end and is short-circuited with the ground conductor 2a or the ground conductor 2b via the connecting conductor 3 at the other end. Since the strip conductors 10a, 10b, 10c, and 10d all operate as resonators, the lengths of the strip conductors 10a, 10b, 10c, and 10d in the longitudinal direction are all odd times λeff / 4 or λeff / 4. It has become. That is, the strip conductors 10a, 10b, 10c, and 10d in the frequency filter 200 all operate as 1/4 wavelength resonators.

The input line 9a, the output line 9b, the strip conductor 10a, the strip conductor 10d, the floating conductor 11a, and the floating conductor 11d are arranged in the second layer 1b of the insulator 1.
The strip conductor 10b, the strip conductor 10c, the floating conductor 11b, and the floating conductor 11c are arranged in the first layer 1a of the insulator 1.

One end of the strip conductor 10a and one end of the strip conductor 10b are arranged so as to be close to each other.
One end of the strip conductor 10c and one end of the strip conductor 10d are arranged so as to be close to each other.
The floating conductor 11a is arranged at a position where a gap is provided from one end of the strip conductor 10a.
The floating conductor 11b is arranged at a position where a gap is provided from one end of the strip conductor 10b.
The floating conductor 11c is arranged at a position where a gap is provided from one end of the strip conductor 10c.
The floating conductor 11d is arranged at a position where a gap is provided from one end of the strip conductor 10d.
The floating conductor 11a is arranged so as to overlap the strip conductor 10b in the direction orthogonal to the first layer 1a.
The floating conductor 11b is arranged so as to overlap the strip conductor 10a in the direction orthogonal to the second layer 1b.
The floating conductor 11c is arranged so as to overlap the strip conductor 10d in the direction orthogonal to the second layer 1b.
The floating conductor 11d is arranged so as to overlap the strip conductor 10b in the direction orthogonal to the first layer 1a.

The strip conductor 10a and the floating conductor 11a arranged in the second layer 1b of the insulator 1 and the strip conductor 10b and the floating conductor 11b arranged in the first layer 1a of the insulator 1 are described in the first embodiment, respectively. The strip conductor 4a and the floating conductor 5a in the resonator coupling structure 100 have the same structure as the strip conductor 4b and the floating conductor 5b.
The strip conductor 10d and the floating conductor 11d arranged in the second layer 1b of the insulator 1 and the strip conductor 10c and the floating conductor 11c arranged in the first layer 1a of the insulator 1 are described in the first embodiment, respectively. The strip conductor 4a and the floating conductor 5a in the resonator coupling structure 100 have the same structure as the strip conductor 4b and the floating conductor 5b.
That is, the frequency filter 200 shown in FIG. 12 includes the resonator coupling structure 100 according to the first embodiment.

The operation of the frequency filter 200 according to the fourth embodiment will be described.
It should be noted that the description of the content that overlaps with the content described in the previous embodiments will be omitted.

In general, in a frequency filter in which a plurality of resonators are electrically coupled, it is necessary to increase the coupling coefficient between the resonators in order to increase the passing bandwidth of the frequency filter. In particular, a frequency filter in which k-stage (k is an integer of 2 or more) resonators are connected in sequence by electric field coupling is an electric field coupling between the first-stage resonator and the second-stage resonator, or k-. In the electric field coupling between the first-stage resonator and the k-th stage resonator, it is necessary to increase the coupling coefficient.

In the frequency filter 200, the strip conductor 10a and the strip conductor 10b are arranged in different layers of the insulator 1, and the strip conductor 10c and the strip conductor 10d are arranged in different layers of the insulator 1, so that a large coupling coefficient is obtained. Have.
Further, as described above, in the frequency filter 200, the strip conductor 10a and the floating conductor 11a, and the strip conductor 10b and the floating conductor 11b have the same structure as the resonator coupling structure 100 according to the first embodiment, and the strip. Since the conductor 10d and the floating conductor 11d and the strip conductor 10c and the floating conductor 11c have the same structure as the resonator coupling structure 100 according to the first embodiment, between the first layer 1a and the second layer 1b. Fluctuations in the coupling coefficient due to variations in thickness can be suppressed.
Therefore, the frequency filter 200 not only has a large coupling coefficient in the electric field coupling between the resonators, but also can suppress fluctuations in the coupling coefficient between the resonators even if there is a manufacturing error. Therefore, the frequency filter 200 can improve the yield of the frequency filter 200 at the time of mass production.

The frequency filter 200 according to the fourth embodiment is shown to be composed of four strip conductors 10a, 10b, 10c, and 10d as an example, but the number of strip conductors in the frequency filter 200 is limited to this. It is not something that is done.
Further, the frequency filter 200 according to the fourth embodiment has shown the one provided with the resonator coupling structure 100 according to the two embodiments 1 as an example, but the frequency filter 200 has been described in the previous embodiments. Any one having one or more of the resonator coupling structures 100, 100a, 100b described above may be used. For example, the frequency filter 200 may be provided with the resonator coupling structures 100, 100a, 100b described in the previous embodiments only in the locations where a large coupling coefficient is required in the electric field coupling between the resonators. ..

Further, in the fourth embodiment, the frequency filter 200 shows, as an example, the strip conductor 10b and the strip conductor 10c arranged in the same layer of the insulator 1, but the frequency filter 200 shows the strip conductor 10b and the strip conductor 10b. The conductor 10c and the conductor 10c may be arranged in different layers. Further, in the frequency filter 200, the strip conductor 10b and the strip conductor 10c are arranged in different layers, and the strip conductor 10b and the floating conductor 11b and the strip conductor 10c and the floating conductor 11c have been described in the previous embodiments. It may be arranged so as to have the same structure as the resonator coupling structures 100, 100a and 100b.

A modified example of the fourth embodiment.
The frequency filter 200a according to the modified example of the fourth embodiment will be described with reference to FIG.
The frequency filter 200a according to the modified example of the fourth embodiment is composed of a three-stage resonator, whereas the frequency filter 200 according to the fourth embodiment is composed of a four-stage resonator. It is a thing.
FIG. 13A is a diagram showing an example of an exploded view of the frequency filter 200a according to the modified example of the fourth embodiment.
FIG. 13B is an arrow view of the frequency filter 200a according to the modified example of the fourth embodiment as viewed from the Y direction shown in FIG. 13A. Note that FIG. 13B is a view in which the insulator 1 and the ground conductor 2a are transparent.
The frequency filter 200a shown in FIG. 13 includes an insulator 1, a ground conductor 2a, a ground conductor 2b, a connecting conductor 3, an input terminal 8a, an output terminal 8b, an input line 9a, an output line 9b, a strip conductor 10a, 10b, 10d, and the like. It includes floating conductors 11a, 11b, 11c, 11d.
In the configuration of the frequency filter 200a according to the modified example of the fourth embodiment, the same reference numerals are given to the same configuration as the frequency filter 200 according to the fourth embodiment, and duplicate description will be omitted. That is, the description of the configuration of FIG. 13A or FIG. 13B having the same reference numerals as those shown in FIGS. 12A or 12B will be omitted.

Hereinafter, description will be made with reference to FIG.
The insulator 1 has a plate-like shape.
The insulator 1 has a first layer 1a and a second layer 1b parallel to each other inside the insulator 1.
The input terminal 8a is a terminal for inputting a high frequency signal.
The output terminal 8b is a terminal for outputting a high frequency signal.
The input line 9a is a line for transmitting a high frequency signal received by the input terminal 8a from the input terminal 8a to the strip conductor 10a.
The output line 9b is a line for transmitting a high frequency signal output from the output terminal 8b from the strip conductor 10d to the output terminal 8b.

Each of the strip conductors 10a, 10b, and 10d in the frequency filter 200a has an open end at one end and is short-circuited with the ground conductor 2a or the ground conductor 2b via the connecting conductor 3 at the other end. Since the strip conductors 10a, 10b, and 10d all operate as resonators, the lengths of the strip conductors 10a, 10b, and 10d in the longitudinal direction are all odd multiples of λeff / 4 or λeff / 4. .. That is, the strip conductors 10a, 10b, and 10d in the frequency filter 200a all operate as 1/4 wavelength resonators.

The input line 9a, the output line 9b, the strip conductor 10a, the strip conductor 10d, the floating conductor 11a, and the floating conductor 11d are arranged in the second layer 1b of the insulator 1.
The strip conductor 10b, the floating conductor 11b, and the floating conductor 11c are arranged in the first layer 1a of the insulator 1.

One end of the strip conductor 10a and one end of the strip conductor 10b are arranged so as to be close to each other.
One end of the strip conductor 10b and one end of the strip conductor 10d are arranged so as to be close to each other.
The floating conductor 11a is arranged at a position where a gap is provided from one end of the strip conductor 10a.
The floating conductor 11b is arranged at a position where a gap is provided from one end of the strip conductor 10b.
The floating conductor 11c is arranged at a position where a gap is provided from one end of the strip conductor 10b.
The floating conductor 11d is arranged at a position where a gap is provided from one end of the strip conductor 10d.
The floating conductor 11a is arranged so as to overlap the strip conductor 10b in the direction orthogonal to the first layer 1a.
The floating conductor 11b is arranged so as to overlap the strip conductor 10a in the direction orthogonal to the second layer 1b.
The floating conductor 11c is arranged so as to overlap the strip conductor 10d in the direction orthogonal to the second layer 1b.
The floating conductor 11d is arranged so as to overlap the strip conductor 10b in the direction orthogonal to the first layer 1a.

The strip conductor 10a and the floating conductor 11a arranged in the second layer 1b of the insulator 1 and the strip conductor 10b and the floating conductor 11b arranged in the first layer 1a of the insulator 1 are described in the first embodiment, respectively. The strip conductor 4a and the floating conductor 5a in the resonator coupling structure 100 have the same structure as the strip conductor 4b and the floating conductor 5b.
The strip conductor 10d and the floating conductor 11d arranged in the second layer 1b of the insulator 1 and the strip conductor 10b and the floating conductor 11c arranged in the first layer 1a of the insulator 1 are described in the first embodiment, respectively. The strip conductor 4a and the floating conductor 5a in the resonator coupling structure 100 have the same structure as the strip conductor 4b and the floating conductor 5b.
That is, the frequency filter 200a shown in FIG. 13 includes the resonator coupling structure 100 according to the first embodiment.

The operation of the frequency filter 200a according to the modified example of the fourth embodiment will be described.
It should be noted that the description of the content that overlaps with the content described in the previous embodiments will be omitted.

In the frequency filter 200a, the strip conductor 10a and the strip conductor 10b are arranged in different layers of the insulator 1, and the strip conductor 10b and the strip conductor 10d are arranged in different layers of the insulator 1, so that a large coupling coefficient is obtained. Have.
Further, as described above, in the frequency filter 200a, the strip conductor 10a and the floating conductor 11a, and the strip conductor 10b and the floating conductor 11b have the same structure as the resonator coupling structure 100 according to the first embodiment, and the strip. Since the conductor 10d and the floating conductor 11d and the strip conductor 10b and the floating conductor 11c have the same structure as the resonator coupling structure 100 according to the first embodiment, between the first layer 1a and the second layer 1b. Fluctuations in the coupling coefficient due to variations in thickness can be suppressed.
Therefore, the frequency filter 200a not only has a large coupling coefficient in the electric field coupling between the resonators, but also can suppress fluctuations in the coupling coefficient between the resonators even if there is a manufacturing error. Therefore, the frequency filter 200a can improve the yield of the frequency filter 200a at the time of mass production.

Embodiment 5.
The frequency filter 200b according to the fifth embodiment will be described with reference to FIG.
FIG. 14A is a diagram showing an example of an exploded view of the frequency filter 200b according to the fifth embodiment.
FIG. 14B is an arrow view of the frequency filter 200b according to the fifth embodiment as viewed from the Y direction shown in FIG. 14A. Note that FIG. 14B is a view in which the insulator 1 is transparent.
The frequency filter 200b shown in FIG. 14 includes an insulator 1, a ground conductor housing 6, an input terminal 8a, an output terminal 8b, an input line 9a, an output line 9b, strip conductors 10a, 10b, 10d, and floating conductors 11a, 11b. It includes 11c, 11d, 11e, 11f, 11g, and 11h.
In the configuration of the frequency filter 200b according to the fifth embodiment, the description of the same configuration as the resonator coupling structures 100, 100a, 100b or the frequency filters 200, 200a described in the previous embodiments will be omitted.

Hereinafter, description will be made with reference to FIG.
The insulator 1 has a plate-like shape.
The insulator 1 has a first layer 1a and a second layer 1b parallel to each other.
The first layer 1a in the insulator 1 is one surface of the insulator 1, and the second layer 1b in the insulator 1 is the other surface of the insulator 1 facing one surface of the insulator 1.
The input terminal 8a is a terminal for inputting a high frequency signal.
The output terminal 8b is a terminal for outputting a high frequency signal.
The input line 9a, the floating conductor 11e, the floating conductor 11b, the strip conductor 10b, the floating conductor 11c, the floating conductor 11h, and the output line 9b are arranged on the first layer 1a of the insulator 1.
The floating conductor 11f, the strip conductor 10a, the floating conductor 11a, the floating conductor 11d, the strip conductor 10d, and the floating conductor 11g are arranged in the second layer 1b of the insulator 1.

One end of the input line 9a is connected to the input terminal 8a, and the other end is an open end.
One end of the output line 9b is connected to the output terminal 8b, and the other end is an open end.
Both ends of the strip conductors 10a, 10b, and 10d are open ends. The lengths of the strip conductors 10a, 10b, and 10d in the longitudinal direction are adjusted so that the strip conductors 10a, 10b, and 10d all operate as resonators.
More specifically, since both ends of the strip conductors 10a, 10b, and 10d are open ends, the strip conductors 10a, 10b, and 10d have any length in the longitudinal direction of the strip conductors 10a, 10b, and 10d. Is also an integral multiple of λeff / 2 or λeff / 2. That is, the strip conductors 10a, 10b, and 10d in the frequency filter 200b all operate as 1/2 wavelength resonators.

The other end of the input line 9a and one end of the strip conductor 10a are arranged so as to be close to each other.
The other end of the strip conductor 10a and one end of the strip conductor 10b are arranged so as to be close to each other.
The other end of the strip conductor 10b and one end of the strip conductor 10d are arranged so as to be close to each other.
The other end of the strip conductor 10d and the other end of the output line 9b are arranged so as to be close to each other.

The floating conductor 11e is arranged at a position where a gap is provided from the other end of the input line 9a.
The floating conductor 11f is arranged at a position where a gap is provided from one end of the strip conductor 10a.
The floating conductor 11a is arranged at a position where a gap is provided from the other end of the strip conductor 10a.
The floating conductor 11b is arranged at a position where a gap is provided from one end of the strip conductor 10b.
The floating conductor 11c is arranged at a position where a gap is provided from the other end of the strip conductor 10b.
The floating conductor 11d is arranged at a position where a gap is provided from one end of the strip conductor 10d.
The floating conductor 11g is arranged at a position where a gap is provided from the other end of the strip conductor 10d.
The floating conductor 11h is arranged at a position where a gap is provided from the other end of the output line 9b.

The floating conductor 11e is arranged so as to overlap the strip conductor 10a in the direction orthogonal to the second layer 1b.
The floating conductor 11b is arranged so as to overlap the strip conductor 10a in the direction orthogonal to the second layer 1b.
The floating conductor 11c is arranged so as to overlap the strip conductor 10d in a direction orthogonal to the second layer 1b.
The floating conductor 11h is arranged so as to overlap the strip conductor 10d in the direction orthogonal to the second layer 1b.
The floating conductor 11f is arranged so as to overlap the input line 9a in the direction orthogonal to the first layer 1a.
The floating conductor 11a is arranged so as to overlap the strip conductor 10b in the direction orthogonal to the first layer 1a.
The floating conductor 11d is arranged so as to overlap the strip conductor 10b in the direction orthogonal to the first layer 1a.
The floating conductor 11g is arranged so as to overlap the output line 9b in the direction orthogonal to the first layer 1a.

The operation of the frequency filter 200b according to the fifth embodiment will be described.
It should be noted that the description of the content that overlaps with the content described in the previous embodiments will be omitted.

The input line 9a and the floating conductor 11e arranged in the first layer 1a of the insulator 1 and the strip conductor 10a and the floating conductor 11f arranged in the second layer 1b of the insulator 1 are described in the first embodiment, respectively. The strip conductor 4a and the floating conductor 5a in the resonator coupling structure 100 have the same structure as the strip conductor 4b and the floating conductor 5b.
The output line 9b and the floating conductor 11h arranged in the first layer 1a of the insulator 1 and the strip conductor 10d and the floating conductor 11g arranged in the second layer 1b of the insulator 1 are described in the first embodiment, respectively. The strip conductor 4a and the floating conductor 5a in the resonator coupling structure 100 have the same structure as the strip conductor 4b and the floating conductor 5b.

The strip conductor 10b and the floating conductor 11b arranged in the first layer 1a of the insulator 1 and the strip conductor 10a and the floating conductor 11a arranged in the second layer 1b of the insulator 1 are described in the first embodiment, respectively. The strip conductor 4a and the floating conductor 5a in the resonator coupling structure 100 have the same structure as the strip conductor 4b and the floating conductor 5b.
The strip conductor 10b and the floating conductor 11c arranged in the first layer 1a of the insulator 1 and the strip conductor 10d and the floating conductor 11d arranged in the second layer 1b of the insulator 1 are described in the first embodiment, respectively. The strip conductor 4a and the floating conductor 5a in the resonator coupling structure 100 have the same structure as the strip conductor 4b and the floating conductor 5b.
That is, a part of the high frequency signal received by the input terminal 8a is an input line 9a, a strip conductor 10a, and a strip conductor in which the strip conductors are electrically coupled by the same structure as the resonator coupling structure 100 according to the first embodiment. It is output from the output terminal 8b via the 10a, the strip conductor 10c, and the output line 9b.

Since the electric field coupling between all the resonators is a coupling having the same structure as the resonator coupling structure 100 according to the first embodiment, the frequency filter 200b has a large coupling coefficient in the electric field coupling between all the resonators. ..
With the above configuration, the frequency filter 200b has a large coupling coefficient in the electric field coupling between the resonators, and the thickness between the first layer 1a and the second layer 1b varies. Fluctuations in the coupling coefficient can be suppressed.
Therefore, the frequency filter 200b not only has a large coupling coefficient in the electric field coupling between the resonators, but also can suppress fluctuations in the coupling coefficient between the resonators even if there is a manufacturing error. Therefore, the frequency filter 200b can improve the yield of the frequency filter 200b at the time of mass production.

As an example, the frequency filter 200b according to the fifth embodiment has the same structure as the resonator coupling structure 100 according to the first embodiment in the electric field coupling between all the resonators. The frequency filter 200b may be any one provided with one or more resonator coupling structures 100, 100a, 100b described in the previous embodiments. For example, the frequency filter 200b may be provided with the resonator coupling structures 100, 100a, 100b described in the previous embodiments only in the locations where a large coupling coefficient is required in the electric field coupling between the resonators. ..

It should be noted that, within the scope of the invention, the present invention is free combination of each embodiment or modification of the embodiment, modification of any component in each embodiment or modification of the embodiment, or , Each embodiment, or any component can be omitted in the modified example of the embodiment.

The resonator coupling structure according to the present invention can be applied to a frequency filter.

100, 100a, 100b Resonator coupling structure, 200, 200a, 200b frequency filter, 1 insulator, 1a 1st layer, 1b 2nd layer, 2a, 2b ground conductor, 3 connecting conductor, 4a, 4b, 10a, 10b, 10c, 10d strip conductor, 5a, 5b, 11a, 11b, 11c, 11d, 11e, 11f, 11g, 11h floating conductor, 6 ground conductor housing, 7a, 7b floating conductor group, 8a input terminal, 8b output terminal, 9a Input line, 9b output line, C, Cb, Cd, Cf, Cg, Cp capacitance, 2Cm, -Cm mutual capacitance, L inductance.

The resonator coupling structure according to the present invention includes a plate-shaped insulator having a first layer and a second layer parallel to each other, a ground conductor whose one surface is arranged parallel to one surface of the insulator, and a first of the insulators. A first strip conductor that is arranged in one layer and has an open end at one end and operates as a first resonator, and a first strip conductor that is arranged in the first layer of an insulator and is arranged at a position where a gap is provided from one end of the first strip conductor. The first floating conductor is provided, and the second strip conductor which is arranged in the second layer of the insulator and has an open end and operates as a second resonator. One end of the two-strip conductor is arranged so as to overlap each other in the direction orthogonal to the first layer and the second layer, and the first floating conductor overlaps the second strip conductor in the direction orthogonal to the second layer. Arranged like this.

Claims (10)

A plate-shaped insulator having a first layer and a second layer parallel to each other,
A ground conductor whose one surface is arranged parallel to one surface of the insulator,
A first strip conductor arranged in the first layer of the insulator, one end of which is an open end, and which operates as a first resonator.
A first floating conductor arranged in the first layer of the insulator and arranged at a position where a gap is provided from one end of the first strip conductor.
A second strip conductor arranged in the second layer of the insulator and having an open end at one end and operating as a second resonator.
With
The one end of the first strip conductor and the one end of the second strip conductor are arranged so as to be close to each other.
The first floating conductor is arranged so as to overlap the second strip conductor in a direction orthogonal to the second layer.
Resonator coupling structure characterized by. The resonance according to claim 1, wherein the length of the long side of the first floating conductor or the length of all the sides of the first floating conductor is 1/4 or less of the wavelength at the operating frequency. Instrument connection structure. The resonator coupling structure according to claim 2, further comprising a first floating conductor group composed of the plurality of first floating conductors. A plate-shaped insulator having a first layer and a second layer parallel to each other,
A ground conductor whose one surface is arranged parallel to one surface of the insulator,
A first strip conductor arranged in the first layer of the insulator, one end of which is an open end, and which operates as a first resonator.
A first floating conductor arranged in the first layer of the insulator and arranged at a position where a gap is provided from one end of the first strip conductor.
A second strip conductor arranged in the second layer of the insulator and having an open end at one end and operating as a second resonator.
A second floating conductor arranged in the second layer of the insulator and arranged at a position where a gap is provided from one end of the second strip conductor.
With
The one end of the first strip conductor and the one end of the second strip conductor are arranged so as to be close to each other.
The second floating conductor is arranged so as to overlap the first strip conductor in a direction orthogonal to the first layer.
The first floating conductor is arranged so as to overlap the second strip conductor in a direction orthogonal to the second layer.
Resonator coupling structure characterized by. The length of the long side of the first floating conductor and the length of the long side of the second floating conductor are 1/4 or less of the wavelength at the operating frequency, or the length of all sides of the first floating conductor. The resonator coupling structure according to claim 4, wherein the length of all sides of the second floating conductor is 1/4 or less of the wavelength at the operating frequency. A group of first floating conductors composed of the plurality of first floating conductors,
A group of second floating conductors composed of the plurality of second floating conductors,
The resonator coupling structure according to claim 5, wherein the resonator coupling structure is provided. The insulator is composed of a dielectric substrate and is composed of a dielectric substrate.
The ground conductor shall be arranged on the surface of the insulator, at a position separated from the surface of the insulator in a direction orthogonal to the surface, or inside the insulator.
The resonator coupling structure according to any one of claims 1 to 6, wherein the resonator coupling structure is characterized. The other end of the first strip conductor and the other end of the second strip conductor are short-circuited with the ground conductor.
The longitudinal length of the first strip conductor and the longitudinal length of the first strip conductor shall be an odd multiple of 1/4 of the wavelength at the operating frequency.
The resonator coupling structure according to any one of claims 1 to 7, wherein the resonator coupling structure is characterized. The other end of the first strip conductor and the other end of the second strip conductor are open ends.
The longitudinal length of the first strip conductor and the longitudinal length of the first strip conductor shall be an integral multiple of 1/2 of the wavelength at the frequency of use.
The resonator coupling structure according to any one of claims 1 to 7, wherein the resonator coupling structure is characterized. An input terminal for inputting high-frequency signals and
An output terminal for outputting high-frequency signals and
With multiple resonators electrically coupled to each other,
With
The input terminal and the output terminal are electrically coupled via the plurality of resonators.
The plurality of resonators include a first resonator and a second resonator.
The first resonator and the second resonator are electrically coupled by the resonator coupling structure according to any one of claims 1 to 9.
A frequency filter characterized by.

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