JP5235826B2 - Directional coupler - Google Patents

Description

  The present invention relates to a directional coupler used in the microwave band.

  Directional couplers are widely used for power monitoring. As a conventional directional coupler, a third strip conductor connecting a first strip conductor and a second strip conductor between a first strip conductor and a second strip conductor, respectively, constituting a right-hand / left-handed composite line. And the structure which provided the short stub which consists of a short circuit means which short-circuits a 3rd strip conductor is known (for example, refer patent document 1, nonpatent literature 1).

  In the directional coupler having such a configuration for forward coupling, the difference between the phase velocity in the coupled line during the even mode operation and the phase velocity in the coupled line during the odd mode operation can be increased. Therefore, a directional coupler that is small and tightly coupled and forward-coupled can be realized.

JP 2009-135918 A

Akimichi Hamada and two others, "Basic study of tightly coupled forward couplers using right / left handed composite lines", IEICE Electronics Society Conference, C-2-31, pp. 56, September 2008

However, the prior art has the following problems.
In a conventional directional coupler, both in the even mode operation and the odd mode operation, in a band in which a high-frequency signal is not propagated between a band that is a left-handed characteristic and a band that is a right-handed characteristic that are passbands. There is a band gap.
Since the band to be forward-coupled is only a band in which the pass band in the even mode operation and the pass band in the odd-mode operation overlap, forward coupling is not performed in the band gap band. That is, since the band for forward coupling becomes discontinuous, the conventional directional coupler has a problem that the frequency band becomes narrow.

  The present invention has been made to solve the above-described problems, and an object thereof is to obtain a directional coupler that is forward-coupled in a small size, a tight coupling, and a wide band.

  A directional coupler according to the present invention includes a first strip conductor formed on a dielectric substrate, a second strip conductor formed on the dielectric substrate so as to face the first strip conductor, and a first strip conductor. A third strip conductor connecting the second strip conductor, a ground conductor formed on the dielectric substrate so as to be separated from the first strip conductor, the second strip conductor and the third strip conductor, and the third strip conductor are grounded Short-circuit means for short-circuiting the potential, a pair of first input / output lines formed close to both ends of the first strip conductor, and a pair of second input / output lines formed close to both ends of the second strip conductor And a distance between the first strip conductor and the second strip conductor is equal to the first strip conductor in a side coupling portion where the first strip conductor and the second strip conductor are side-coupled. Are those within twice the one shorter distance to the ground conductor from the distance and a second strip conductor up al ground conductor.

  According to the directional coupler according to the present invention, in the side coupling portion where the first strip conductor and the second strip conductor are side-coupled, the distance between the first strip conductor and the second strip conductor is the first. By setting the distance from the strip conductor to the ground conductor and the distance from the second strip conductor to the ground conductor to be less than twice the shorter one, there is no band gap in both the even mode operation and the odd mode operation. The left-handed passband and the right-handed passband can be made continuous. In addition, by providing a third strip conductor that connects the first strip conductor and the second strip conductor, and a short-circuit means that short-circuits the third strip conductor to the ground potential, the frequency characteristics of the phase constant during even mode operation are provided. And the frequency characteristic of the phase constant during the odd mode operation can be changed so as to translate. Therefore, it is possible to obtain a directional coupler that performs forward coupling with a small size, a tight coupling, and a wide band.

It is a top view which shows the directional coupler which concerns on Embodiment 1 of this invention. It is sectional drawing which cut | disconnected the directional coupler shown in FIG. 1 along the AA 'line. It is a circuit diagram which shows the equivalent circuit at the time of even mode operation | movement at the time of assuming a magnetic wall along the BB 'line | wire of the directional coupler shown in FIG. It is a circuit diagram which shows the equivalent circuit at the time of odd mode operation | movement when an electrical wall is assumed along the BB 'line | wire of the directional coupler shown in FIG. FIG. 4 is an explanatory diagram showing dispersion characteristics when L ^e _R · C ^e _L is larger than L ^e _L · C ^e _{R in} the equivalent circuit shown in FIG. 3. FIG. 4 is an explanatory diagram showing dispersion characteristics when L ^e _R · C ^e _L and L ^e _L · C ^e _R are equal in the equivalent circuit shown in FIG. 3. It is explanatory drawing which shows a dispersion characteristic when a band gap does not exist and the dispersion characteristic at the time of even mode operation | movement shifts greatly with respect to the dispersion characteristic at the time of odd mode operation | movement. It is a top view which shows the directional coupler which concerns on Embodiment 2 of this invention. It is a top view which shows another directional coupler which concerns on Embodiment 2 of this invention. It is a top view which shows the directional coupler which concerns on Embodiment 3 of this invention. It is a top view which shows the directional coupler which concerns on Embodiment 4 of this invention. It is a top view which shows the directional coupler which concerns on Embodiment 5 of this invention. It is a top view which shows another directional coupler which concerns on Embodiment 5 of this invention. It is a top view which shows the directional coupler which concerns on Embodiment 6 of this invention. It is a top view which shows the directional coupler which concerns on Embodiment 7 of this invention. It is sectional drawing which cut | disconnected the directional coupler shown in FIG. 15 along CC 'line. It is a top view which shows the directional coupler which concerns on Embodiment 8 of this invention. It is sectional drawing which cut | disconnected the directional coupler shown in FIG. 17 along CC 'line. It is a top view which shows the directional coupler which concerns on Embodiment 9 of this invention. It is sectional drawing which cut | disconnected the directional coupler shown in FIG. 19 along CC 'line. It is a top view which shows the directional coupler which concerns on Embodiment 10 of this invention. It is a circuit diagram which shows the equivalent circuit at the time of assuming a magnetic wall or an electrical wall along the BB 'line | wire of the directional coupler shown in FIG. FIG. 23 is a circuit diagram showing an equivalent circuit when a capacitor is replaced in the equivalent circuit shown in FIG. 22. It is a top view which shows the directional coupler which concerns on Embodiment 11 of this invention. It is a top view which shows the directional coupler which concerns on Embodiment 12 of this invention. It is a top view which shows the directional coupler which concerns on Embodiment 13 of this invention. It is a top view which shows the directional coupler which concerns on Embodiment 14 of this invention. It is a top view which shows the directional coupler which concerns on Embodiment 15 of this invention. It is a top view which shows the directional coupler which concerns on Embodiment 16 of this invention. It is a top view which shows another directional coupler which concerns on Embodiment 16 of this invention. It is a top view which shows the directional coupler which concerns on Embodiment 17 of this invention. It is a top view which shows the directional coupler which concerns on Embodiment 18 of this invention.

  Hereinafter, preferred embodiments of the directional coupler according to the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts will be described with the same reference numerals.

Embodiment 1 FIG.
1 is a plan view showing a directional coupler according to Embodiment 1 of the present invention. FIG. 2 is a cross-sectional view of the directional coupler shown in FIG. 1 cut along the line AA ′.
The directional coupler according to Embodiment 1 of the present invention is configured using a microstrip line.

  1 and 2, the directional coupler includes a dielectric substrate 1, a ground conductor 2 formed on one surface (back surface) of the dielectric substrate 1, and the other surface (front surface) of the dielectric substrate 1. The first strip conductor 10, the second strip conductor 20, the third strip conductor 30a, the pair of first input / output lines 41 and 42, the pair of second input / output lines 51 and 52, and the dielectric substrate 1 And a through hole 31 (short-circuit means) which is a connecting conductor provided penetrating therethrough.

  The first strip conductor 10 and the second strip conductor 20 are formed to face each other. Further, the third strip conductor 30 a connects the first strip conductor 10 and the second strip conductor 20. The ground conductor 2 is formed separately from the first strip conductor 10, the second strip conductor 20, and the third strip conductor 30a. The through hole 31 shorts the third strip conductor 30a to the ground conductor 2 (ground potential).

  Here, the electrical length of the short stub formed by half of the third strip conductor 30a (from the through hole 31 to the first strip conductor 10 or the second strip conductor 20) and the through hole 31 is 0 indicating inductivity, respectively. It is set to not less than 90 degrees and not more than 90 degrees. Also, the unit of the first strip conductor 10, the second strip conductor 20, the third strip conductor 30a, and the through hole 31 is referred to as a unit cell 100a.

  The first input / output lines 41 and 42 are formed close to both ends of the first strip conductor 10. Input / output gaps 61 and 62 are formed between the first strip conductor 10 and the first input / output lines 41 and 42, respectively. The second input / output lines 51 and 52 are formed close to both ends of the second strip conductor 20. Input / output gaps 71 and 72 are formed between the second strip conductor 20 and the second input / output lines 51 and 52, respectively.

  The first strip conductor 10 has a first conductor portion 11, a second conductor portion 12, and a third conductor portion 13. Further, the second strip conductor 20 has a first conductor portion 21, a second conductor portion 22, and a third conductor portion 23. The first conductor portion 11, the first conductor portion 21, the second conductor portion 12, the second conductor portion 22, and the third conductor portion 13 and the third conductor portion 23 are formed in parallel to each other. Yes. A third strip conductor 30 a is formed between the second conductor portion 12 and the second conductor portion 22.

  Here, the 1st conductor part 11 and the 1st conductor part 21, and the 3rd conductor part 13 and the 3rd conductor part 23 are the side coupling | bonding by which the 1st strip conductor 10 and the 2nd strip conductor 20 are side-coupled, respectively. Forming part. In the side coupling portion, the distance between the first conductor portion 11 and the first conductor portion 21 is any of the distance from the first conductor portion 11 to the ground conductor 2 and the distance from the first conductor portion 21 to the ground conductor 2. Or less than twice the shorter one. Similarly, the distance between the third conductor portion 13 and the third conductor portion 23 is either the distance from the third conductor portion 13 to the ground conductor 2 or the distance from the third conductor portion 23 to the ground conductor 2. Or less than twice the shorter one.

FIG. 3 is a circuit diagram showing an equivalent circuit at the time of even mode operation when a magnetic wall is assumed along the line BB ′ of the directional coupler shown in FIG.
The strip line represented by the equivalent circuit of FIG. 3 includes a first strip conductor 10, first input / output lines 41 and 42, a third strip conductor 30a closer to the first strip conductor 10 than the section BB ′, and a section. The through hole 31 is closer to the first strip conductor 10 than BB ′. That is, this equivalent circuit shows a circuit when the directional coupler operates in an even mode.

  The equivalent circuit during the even mode operation of the directional coupler includes a transmission line model 101a, a capacitor 102a, an inductor 103a, an inductor 103b, a capacitor 102b, a transmission line model 101b, an inductor 103a, and an inductor 103b connected in series. The capacitor 104 and the inductor 105 are connected to each other with one end connected in parallel and the other end connected to the ground (ground potential).

  The transmission line model 101 a corresponds to the first input / output line 41. The capacitor 102 a corresponds to the capacitance of the input / output gap 61. The inductor 103a corresponds to the inductance of half of the first conductor portion 11 and the second conductor portion 12 (on the first input / output line 41 side of the cross section AA ′). The inductor 103 b corresponds to the other half of the second conductor portion 12 (on the first input / output line 42 side of the cross section AA ′) and the inductance of the third conductor portion 13. The capacitor 102 b corresponds to the capacitance of the input / output gap 62. The transmission line model 101 b corresponds to the first input / output line 42.

  The capacitor 104 corresponds to the capacitance of the first conductor portion 11, the second conductor portion 12, the third conductor portion 13, and the third strip conductor 30a closer to the first strip conductor 10 than the section BB ′. The inductor 105 is connected in parallel with the capacitor 104, and includes a third strip conductor 30a closer to the first strip conductor 10 than the section BB ′ and a through hole 31 closer to the first strip conductor 10 than the section BB ′. Corresponds to inductance.

FIG. 4 is a circuit diagram showing an equivalent circuit during an odd mode operation when an electric wall is assumed along the line BB ′ of the directional coupler shown in FIG.
4 includes the first strip conductor 10, the first input / output lines 41 and 42, and the third strip conductor 30a closer to the first strip conductor 10 than the cross-section BB ′. Has been. That is, this equivalent circuit shows a circuit when the directional coupler operates in an odd mode.

  The equivalent circuit during the odd mode operation of the directional coupler includes a transmission line model 201a, a capacitor 202a, an inductor 203a, an inductor 203b, a capacitor 202b, and a transmission line model 201b, an inductor 203a and an inductor 203b, which are connected in series. It is represented using a capacitor 204 and an inductor 205 each having one end connected in parallel and the other end connected to the ground.

  The transmission line model 201 a corresponds to the first input / output line 41. The capacitor 202 a corresponds to the capacitance of the input / output gap 61. The inductor 203a corresponds to the inductance of half of the first conductor portion 11 and the second conductor portion 12 (on the first input / output line 41 side of the cross section AA ′). Further, the inductor 203 b corresponds to the other half of the second conductor portion 12 (on the first input / output line 42 side of the cross section AA ′) and the inductance of the third conductor portion 13. The capacitor 202 b corresponds to the capacitance of the input / output gap 62. The transmission line model 201 b corresponds to the first input / output line 42.

  The capacitor 204 corresponds to the capacitance of the first conductor portion 11, the second conductor portion 12, the third conductor portion 13, and the third strip conductor 30a closer to the first strip conductor 10 than the cross section BB ′. The inductor 205 is connected in parallel with the capacitor 104 and corresponds to the inductance of the third strip conductor 30a on the first strip conductor 10 side with respect to the cross section BB ′.

Next, the operation of the directional coupler according to Embodiment 1 of the present invention will be described.
First, in the equivalent circuit shown in FIG. 3 or FIG. 4, the propagation constant γ ^e between one end of the capacitor 102a (on the transmission line model 101a) and the other end of the capacitor 102b (on the transmission line model 101b), and the capacitor 202a The propagation constant γ ^o between one end of the capacitor 202 and the other end of the capacitor 202b is expressed by the following equation (1).

In equation (1), i represents e or o, α ^e is an attenuation constant during even mode operation, α ^o is an attenuation constant during odd mode operation, β ^e is a phase constant during even mode operation, and β ^o is The phase constants during odd mode operation are shown.
In the equation (1), the impedance Z ⁱ (i = e, o) is represented by the following equation (2), and the admittance Y ⁱ (i = e, o) is represented by the following equation (3). .

In equations (2) and (3), ω is the angular frequency, L ^e _R is the inductance of the inductors 103a and 103b, L ^o _R is the inductance of the inductors 203a and 203b, C ^e _L is the capacitance of the capacitors 102a and 102b, and C ^o _L represents the capacitance of the capacitors 202a and 202b, C ^e _R represents the capacitance of the capacitor 104, C ^o _R represents the capacitance of the capacitor 204, L ^e _L represents the inductance of the inductor 105, and L ^o _L represents the inductance of the inductor 205, respectively.

Next, in the equivalent circuit shown in FIG. 3, the dispersion characteristics when L ^e _R · C ^e _L is larger than L ^e _L · C ^e _R are shown in FIG.
In FIG. 5, f ^e _cl indicates the frequency at the band edge on the low frequency side in the band where the value of the phase constant β ^e is other than 0, and is expressed by the following equation (4). F ^e _se indicates the lower frequency at which the value of the phase constant β ^e is 0, and is expressed by the following equation (5). F ^e _sh indicates the higher frequency at which the value of the phase constant β ^e is 0, and is represented by the following equation (6). Further, f ^e _cr indicates the frequency at the band edge on the high frequency side in a band where the value of the phase constant β ^e is other than 0, and is expressed by the following equation (7). In the following formulas (4) to (7), ω ⁱ ₀ is represented by the following formula (8), ω ⁱ _L is represented by the following formula (9), and κ ⁱ is represented by the following formula (10).

For dispersion characteristic shown in FIG. ^5, band from the band and ^f _{e sh} from _{f e cl} to ^f _{e se} to ^f _{e cr} is a pass band. On the other hand, since the phase constant β ^e is 0 in the band from f ^e _se to f ^e _sh , a high frequency signal is not propagated due to a band gap. That is, since the pass band ^(from the band and ^f _{e sh} from _{f e cl} to ^f _{e se} to ^f _{e cr)} is discontinuous, the pass band becomes narrow band.

Next, FIG. 6 shows dispersion characteristics when L ^e _R · C ^e _L is equal to L ^e _L · C ^e _R in the equivalent circuit shown in FIG.
As shown in FIG. 6, when L ^e _R · C ^e _L and L ^e _L · C ^e _R are equal, f ^e _se and f ^e _sh coincide with each other, so that a dispersion characteristic with no band gap is obtained. Therefore, since the pass band is continuous from f ^e _cl to f ^e _cr , the pass band becomes a wide band. That is, by making L ^e _R · C ^e _L and L ^e _L · C ^e _R equal, wide band pass characteristics can be realized.

In addition, although the case at the time of even mode operation | movement was demonstrated here, similarly, also at the time of odd mode operation | movement, by making L ^o _R * C ^o _L and L ^o _L * C ^o _R equal, it is broadband pass. Characteristics can be realized.

Here, let us consider a case where there is no band gap in both the even mode operation and the odd mode operation, and the dispersion characteristic in the even mode operation is largely parallel to the dispersion characteristic in the odd mode operation. The dispersion characteristics in this case are shown in FIG.
As shown in FIG. 7, since there is no band gap, a wide band pass characteristic is realized in both the even mode operation and the odd mode operation. Further, in the even mode operation and the odd mode operation, the band from f ^o _cl to f ^e _cr becomes a common pass band in each operation, and thus the frequency band becomes wide.

  In addition, since the dispersion characteristics during even mode operation are greatly parallel to the dispersion characteristics during odd mode operation, the difference in phase constant between even mode operation and odd mode operation increases, and even mode operation occurs. The difference in the phase constant is substantially constant in the band that becomes the pass band in both the hour mode and the odd mode operation. From the above, if the dispersion characteristic shown in FIG. 7 can be realized, it is possible to realize a wide-band forward coupling by tight coupling.

Next, the relationship between the element values in the equivalent circuit during the even mode operation and the odd mode operation of the directional coupler according to Embodiment 1 of the present invention will be described.
In the directional coupler according to Embodiment 1 of the present invention, as described above, the distance between the first conductor portion 11 and the first conductor portion 21 is the distance from the first conductor portion 11 to the ground conductor 2. In addition, the distance from the first conductor portion 21 to the ground conductor 2 is set to be within twice the shorter one. Similarly, the distance between the third conductor portion 13 and the third conductor portion 23 is either the distance from the third conductor portion 13 to the ground conductor 2 or the distance from the third conductor portion 23 to the ground conductor 2. Or less than twice the shorter one. Therefore, electromagnetic coupling occurs at the side coupling portion.

Therefore, during the even mode operation, mutual inductance is generated between the first conductor portion 11 and the first conductor portion 21 and between the third conductor portion 13 and the third conductor portion 23. The values of the inductors 103a and 103b in the equivalent circuit are larger than those of the inductors 203a and 203b in the equivalent circuit during the odd mode operation. That is, L ^e _R is larger than L ^o _R.

Further, during odd mode operation, mutual capacitance is generated between the first conductor portion 11 and the first conductor portion 21 and between the third conductor portion 13 and the third conductor portion 23. The value of the capacitor 104 in the equivalent circuit is smaller than that of the capacitor 204 in the equivalent circuit during the odd mode operation. That is, C ^e _R is smaller than C ^o _R.

On the other hand, capacitors 102a and 102b respectively corresponding to the capacitances of the input / output gaps 61 and 62 in the equivalent circuit during the even mode operation, and capacitors 202a corresponding to the capacitances of the input / output gaps 61 and 62 in the equivalent circuit during the odd mode operation, respectively. , 202b is not affected by the electromagnetic coupling generated in the side coupling portion. That is, C ^e _L and C ^o _L have the same value.

  Here, in the even mode operation, the second conductor portion 12 is connected to the ground conductor 2 via the third strip conductor 30a and the through hole 31 on the first strip conductor 10 side from the cross section BB ′. Yes. Further, during the odd mode operation, since the cross section BB ′ is an electric wall, the second conductor portion 12 passes only through the third strip conductor 30a closer to the first strip conductor 10 than the cross section BB ′. Are connected to the ground conductor 2.

From this, in the even mode operation, the length until the second conductor portion 12 is connected to the ground conductor 2 is longer by the through hole 31 than in the odd mode operation. Therefore, the value of the inductor 105 in the equivalent circuit during the even mode operation is larger than the inductor 205 in the equivalent circuit during the odd mode operation. That is, L ^e _L is larger than L ⁰ _L.
In summary, the relationship between the element values in the equivalent circuit during the even mode operation and the odd mode operation is expressed by the following equations (11) to (14).

^{_{L e R> L o R (}} 11)
C ^e _R <C ^o _R (12)
C ^e _L = C ^o _L (13)
L ^e _L > L ^o _L (14)

From the above equations (5), (11), and (13), it can be seen that f ^e _se is smaller than f ^o _se (see the following equation (15)). Further, in consideration of the relationship between Expression (12) and Expression (14), the following Expressions (15) to (19) are satisfied, and the difference in phase constant β ⁱ between even mode operation and odd mode operation is The value of each capacitor and inductor can be determined to be large. That is, the dispersion characteristic shown in FIG. 7 can be realized.

^{_{f e se <f o se (}} 15)
f ^e _se = f ^e _sh (16)
f ^o _se = f ^o _sh (17)
f ^e _cl <f ^o _cl (18)
f ^e _cr <f ^o _cr (19)

From what has been described so far, the values of the capacitors and the inductors are determined so that the equations (15) to (19) are satisfied and the difference in the phase constant β ⁱ between the even mode operation and the odd mode operation is large. Thus, the dispersion characteristics shown in FIG. 7 can be realized during the even mode operation and the odd mode operation. In other words, by determining the dimensions of the directional coupler according to Embodiment 1 of the present invention so that the equivalent circuit realizes the dispersion characteristic shown in FIG. Can do.

Here, the directional coupler according to the first embodiment of the present invention is coupled by the difference of the phase constant β ⁱ between the even mode operation and the odd mode operation, and thus becomes forward coupling. Further, the larger the difference between the phase velocity during the even mode operation and the phase velocity during the odd mode operation, the closer the directional coupler of the forward coupling becomes, but the phase constant β ^e during the even mode operation and the odd mode The phase constant β ^o at the time of operation can be changed so as to translate, and the amount of translation can be increased, so that the difference in the phase constant β ⁱ becomes large and tight coupling occurs. Further, since there is no band gap in both the even mode operation and the odd mode operation, a wide band is obtained. Further, as compared with a general directional coupler using a right-handed line, if the amount of coupling is the same, the size can be greatly reduced.

  As described above, according to the first embodiment, in the side coupling portion where the first strip conductor and the second strip conductor are side-coupled, the distance between the first strip conductor and the second strip conductor is By setting the distance from the first strip conductor to the ground conductor and the distance from the second strip conductor to the ground conductor to be less than twice the shorter one, there is no band gap in both the even mode operation and the odd mode operation. The left-handed passband and the right-handed passband can be made continuous. In addition, by providing a third strip conductor that connects the first strip conductor and the second strip conductor, and a short-circuit means that short-circuits the third strip conductor to the ground potential, the frequency characteristics of the phase constant during even mode operation are provided. And the frequency characteristic of the phase constant during the odd mode operation can be changed so as to translate. Therefore, it is possible to obtain a directional coupler that performs forward coupling with a small size, a tight coupling, and a wide band.

In the first embodiment, it has been described that the ground conductor 2 is formed on the back surface of the dielectric substrate 1. However, the present invention is not limited to this, and the ground conductor 2 is formed on the surface of the dielectric substrate 1 in the same manner as the first strip conductor 10, the second strip conductor 20, the third strip conductor 30a, etc., and constitutes a coplanar line. May be. When the dielectric substrate 1 is a multilayer substrate, the ground conductor 2, the first strip conductor 10, the second strip conductor 20, the third strip conductor 30a, etc. may be formed on the surface of the layer, It may be formed between layers.
In these cases, the same effect as in the first embodiment can be obtained. These modifications can be similarly applied to the following embodiments.

Moreover, in the said Embodiment 1, the 1st conductor part 11 and the 1st conductor part 21 which are located in the both ends of the 1st strip conductor 10 and the 2nd strip conductor 20, the 3rd conductor part 13 and the 3rd conductor part 23, It has been explained that the side coupling portion is formed. However, the present invention is not limited to this, and the side coupling portion may be formed only at one end of the first strip conductor 10 and the second strip conductor 20, or may be formed at a location connected by the third strip conductor 30a. Good.
In these cases, the same effect as in the first embodiment can be obtained. These modifications can be similarly applied to the following embodiments.

Embodiment 2. FIG.
FIG. 8 is a plan view showing a directional coupler according to Embodiment 2 of the present invention.
The directional coupler shown in FIG. 8 is configured by arranging three unit cells 100a in series in the directional coupler shown in FIG.

  Input / output gaps 61 and 62 are formed between the first strip conductor 10 and the first input / output lines 41 and 42, respectively. Input / output gaps 71 and 72 are formed between the second strip conductor 20 and the second input / output lines 51 and 52, respectively. A unit cell gap 80 is formed between the first strip conductors 10 and between the second strip conductors 20. That is, the unit cells 100a are connected in cascade via the inter-unit cell gap 80.

Next, the operation of the directional coupler according to Embodiment 2 of the present invention will be described.
The directional coupler according to Embodiment 2 of the present invention is similar to the directional coupler according to Embodiment 1 described above in that the phase constant β ^e during even mode operation and the phase constant β ^o during odd mode operation are as follows. Can be changed so as to translate, and the amount of translation can be increased, so that the difference in the phase constant β ⁱ becomes large, which results in tight coupling and forward coupling. Further, since there is no band gap in both the even mode operation and the odd mode operation, a wide band is obtained. In addition, as compared with a general directional coupler using a right-handed line, if the amount of coupling is the same, the size can be greatly reduced.

As described above, according to the second embodiment, the same effect as in the first embodiment can be obtained.
Further, the directional coupler according to Embodiment 2 of the present invention is a side coupling portion in which the first strip conductor and the second strip conductor are side-coupled as compared to the directional coupler according to Embodiment 1 described above. Since the (coupled line portion) is long, more tight coupling can be achieved.

  In the second embodiment, the shapes of the input / output gaps 61, 62, 71, 72 and the unit cell gap 80 are two opposing lines, but the present invention is not limited to this. Even when the input / output gaps 61, 62, 71, 72 and the inter-unit cell gap 80 are interdigital capacitors as shown in FIG. 9, the same effects as those of the second embodiment can be obtained. Here, by making the gap an interdigital capacitor, the capacitance corresponding to the input / output gaps 61, 62, 71, 72 and the unit cell gap 80 is increased, and a directional coupler that is tightly coupled at a lower frequency is formed. can do.

  In the second embodiment, the directional coupler is configured by cascading three unit cells 100a. However, the present invention is not limited to this, and two or more unit cells 100a may be cascaded. Good.

Embodiment 3 FIG.
FIG. 10 is a plan view showing a directional coupler according to Embodiment 3 of the present invention.
The directional coupler according to Embodiment 3 of the present invention is configured using a microstrip line.

10, this directional coupler includes a third strip conductor 30b instead of the third strip conductor 30a shown in FIG.
The third strip conductor 30b connects the first strip conductor 10 and the second strip conductor 20, and is formed so as to cross the first strip conductor 10 and the second strip conductor 20 and extend outward. Further, through holes 31 for short-circuiting the third strip conductor 30b to the ground conductor 2 are formed at both ends of the third strip conductor 30b.

Here, the electrical lengths of the short stubs formed by the third strip conductor 30b and the through-hole 31 in the portion extending outwardly intersecting the first strip conductor 10 or the second strip conductor 20 are inductive, respectively. It is set to 0 degree or more and 90 degrees or less. Also, the unit of the first strip conductor 10, the second strip conductor 20, the third strip conductor 30b, and the through hole 31 is referred to as a unit cell 100b.
Since other configurations are the same as those in the first embodiment, description thereof is omitted.

Next, the operation of the directional coupler according to Embodiment 3 of the present invention will be described.
In the directional coupler according to Embodiment 3 of the present invention, similarly to the directional coupler according to Embodiment 1 described above, a magnetic wall or an electric wall is assumed along the cross-section BB ′ serving as a symmetry plane. The equivalent circuits at that time are the equivalent circuits shown in FIGS.

  At this time, the line width of the portion of the third strip conductor 30b existing between the first strip conductor 10 and the second strip conductor 20 is made narrow so that it can be ignored during the even mode operation. On the other hand, during the odd-mode operation, the first strip conductor 10 has the cross section BB ′ as an electric wall, and therefore via the third strip conductor 30b closer to the first strip conductor 10 than the cross section BB ′. It is connected to the ground conductor 2.

That is, the inductance L ^e _L of the inductor 105 during the even mode operation is different from the inductance L ^o _L of the inductor 205 during the odd mode operation. Further, since electromagnetic coupling occurs between the first conductor portion 11 and the first conductor portion 21 and between the third conductor portion 13 and the third conductor portion 23, the capacitances of the capacitors 102a and 102b during the even mode operation. C ^e _L and the capacitance C ^e _{R of the} capacitor 104 are different from the capacitance C ^o _L of the capacitors 202 a and 202 b and the capacitance C ^o _{R of the} capacitor 204 during the odd mode operation.

Therefore, similarly to the directional coupler according to the first embodiment described above, the phase constant β ^e during the even mode operation and the phase constant β ^o during the odd mode operation can be changed so as to translate, Since the amount of the parallel movement can be increased, the difference in the phase constant β ⁱ is increased, resulting in tight coupling and forward coupling. Further, since there is no band gap in both the even mode operation and the odd mode operation, a wide band is obtained.
That is, according to the third embodiment, the same effect as in the first embodiment can be obtained.

Embodiment 4 FIG.
FIG. 11 is a plan view showing a directional coupler according to Embodiment 4 of the present invention.
The directional coupler shown in FIG. 11 is configured by arranging three unit cells 100b in series in the directional coupler shown in FIG.

  Input / output gaps 61 and 62 are formed between the first strip conductor 10 and the first input / output lines 41 and 42, respectively. Input / output gaps 71 and 72 are formed between the second strip conductor 20 and the second input / output lines 51 and 52, respectively. A unit cell gap 80 is formed between the first strip conductors 10 and between the second strip conductors 20. That is, the unit cells 100b are connected in cascade via the inter-unit cell gap 80.

Next, the operation of the directional coupler according to Embodiment 4 of the present invention will be described.
The directional coupler according to Embodiment 4 of the present invention is similar to the directional coupler according to Embodiment 3 described above in that the phase constant β ^e during even mode operation and the phase constant β ^o during odd mode operation are as follows. Can be changed so as to translate, and the amount of translation can be increased, so that the difference in the phase constant β ⁱ becomes large, which results in tight coupling and forward coupling. Further, since there is no band gap in both the even mode operation and the odd mode operation, a wide band is obtained. Further, as compared with a general directional coupler using a right-handed line, if the amount of coupling is the same, the size can be greatly reduced.

As described above, according to the fourth embodiment, the same effect as in the third embodiment can be obtained.
Further, the directional coupler according to Embodiment 4 of the present invention is a side coupling portion in which the first strip conductor and the second strip conductor are side-coupled to the directional coupler according to Embodiment 3 described above. Since the (coupled line portion) is long, more tight coupling can be achieved.

  In the fourth embodiment, the directional coupler is configured by cascading three unit cells 100b. However, the present invention is not limited to this, and two or more unit cells 100b may be cascaded. Good.

Embodiment 5 FIG.
FIG. 12 is a plan view showing a directional coupler according to Embodiment 5 of the present invention.
In FIG. 12, the directional coupler includes a third strip conductor 30c instead of the third strip conductor 30a shown in FIG.

  The third strip conductor 30c connects the first strip conductor 10 and the second strip conductor 20, and from the middle between the first strip conductor 10 and the second strip conductor 20, the third conductor portion 13 and the third conductor portion. It has a T-branch portion that branches in 23 directions (right direction in the figure). A through hole 31 that short-circuits the third strip conductor 30c to the ground conductor 2 is formed in the T branch portion.

Here, the electrical length of the short stub formed by the half of the third strip conductor 30c (from the through hole 31 to the first strip conductor 10 or the second strip conductor 20) and the through hole 31 is 0 indicating inductivity. It is set to 90 degrees or more. A unit cell 100c is a combination of the first strip conductor 10, the second strip conductor 20, the third strip conductor 30c, and the through hole 31.
Since other configurations are the same as those in the first embodiment, description thereof is omitted.

Next, the operation of the directional coupler according to Embodiment 5 of the present invention will be described.
In the directional coupler according to Embodiment 5 of the present invention, similarly to the directional coupler according to Embodiment 1 described above, a magnetic wall or an electric wall is assumed along the cross-section BB ′ serving as a symmetry plane. The equivalent circuits at that time are the equivalent circuits shown in FIGS.

  During the even mode operation, the second strip conductor 20 is connected to the ground conductor 2 via the third strip conductor 30c and the through hole 31 closer to the first strip conductor 10 than the cross section BB ′. On the other hand, during the odd-mode operation, the second strip conductor 20 has the cross section BB ′ as an electric wall, and therefore via the third strip conductor 30 c closer to the first strip conductor 10 than the cross section BB ′. It is connected to the ground conductor 2.

That is, the inductance L ^e _L of the inductor 105 during the even mode operation is different from the inductance L ^o _L of the inductor 205 during the odd mode operation. Further, since electromagnetic coupling occurs between the first conductor portion 11 and the first conductor portion 21 and between the third conductor portion 13 and the third conductor portion 23, the capacitances of the capacitors 102a and 102b during the even mode operation. C ^e _L and the capacitance C ^e _{R of the} capacitor 104 are different from the capacitance C ^o _L of the capacitors 202 a and 202 b and the capacitance C ^o _{R of the} capacitor 204 during the odd mode operation.

Therefore, similarly to the directional coupler according to the first embodiment described above, the phase constant β ^e during the even mode operation and the phase constant β ^o during the odd mode operation can be changed so as to translate, Since the amount of the parallel movement can be increased, the difference in the phase constant β ⁱ is increased, resulting in tight coupling and forward coupling. Further, since there is no band gap in both the even mode operation and the odd mode operation, a wide band is obtained.
That is, according to the fifth embodiment, the same effect as in the first embodiment can be obtained.

  In the fifth embodiment, it has been described that the third strip conductor 30c has the T branch portion, and the through hole 31 is formed in the T branch portion. However, the present invention is not limited to this, and as shown in FIG. 13, the third strip conductor 30 d is further provided at the end of the T branch portion formed in the middle between the first strip conductor 10 and the second strip conductor 20. And the through hole 31 may be formed at the tip of the T branching portion.

Embodiment 6 FIG.
FIG. 14 is a plan view showing a directional coupler according to Embodiment 6 of the present invention.
The directional coupler shown in FIG. 14 is configured by arranging three unit cells 100c in series in the directional coupler shown in FIG.

  Input / output gaps 61 and 62 are formed between the first strip conductor 10 and the first input / output lines 41 and 42, respectively. Input / output gaps 71 and 72 are formed between the second strip conductor 20 and the second input / output lines 51 and 52, respectively. A unit cell gap 80 is formed between the first strip conductors 10 and between the second strip conductors 20. That is, the unit cells 100c are connected in cascade via the inter-unit cell gap 80.

Next, the operation of the directional coupler according to Embodiment 6 of the present invention will be described.
The directional coupler according to Embodiment 6 of the present invention is similar to the directional coupler according to Embodiment 5 described above in that the phase constant β ^e during even mode operation and the phase constant β ^o during odd mode operation are as follows. Can be changed so as to translate, and the amount of translation can be increased, so that the difference in the phase constant β ⁱ becomes large, which results in tight coupling and forward coupling. Further, since there is no band gap in both the even mode operation and the odd mode operation, a wide band is obtained. Further, as compared with a general directional coupler using a right-handed line, if the amount of coupling is the same, the size can be greatly reduced.

As described above, according to the sixth embodiment, the same effect as in the fifth embodiment can be obtained.
Further, the directional coupler according to Embodiment 6 of the present invention is a side coupling portion in which the first strip conductor and the second strip conductor are side-coupled to the directional coupler according to Embodiment 5 described above. Since the (coupled line portion) is long, more tight coupling can be achieved.

In the sixth embodiment, the directional coupler is configured by cascading three unit cells 100c. However, the present invention is not limited to this, and two or four or more unit cells 100c may be cascaded. Good.
Further, a directional coupler may be configured by cascading a plurality of unit cells 100d including the first strip conductor 10, the second strip conductor 20, the third strip conductor 30d, and the through hole 31 shown in FIG. .

Embodiment 7 FIG.
FIG. 15 is a plan view showing a directional coupler according to Embodiment 7 of the present invention. FIG. 16 is a cross-sectional view of the directional coupler shown in FIG. 15 cut along the line CC ′. In FIG. 15, the input / output unit capacitance forming conductor 111 and the unit cell capacitance forming conductor 112 are shown to be visible on the surface of the dielectric substrate 1, but this is for ease of understanding. Actually, it is formed inside the dielectric substrate 1 as shown in FIG.

15 and 16, the directional coupler includes an input / output section capacitance forming conductor 111, a unit cell capacitance forming conductor 112, and a through hole 113 in addition to the directional coupler shown in FIG.
The input / output unit capacitance forming conductor 111 is disposed inside the dielectric substrate 1 below the input / output gaps 61, 62, 71, 72. The inter-unit cell capacity forming conductor 112 is disposed inside the dielectric substrate 1 below the inter-unit cell gap 80.

The input / output portion capacitance forming conductors 111 disposed below the input / output gaps 61 and 71 are connected to the first strip conductor 10 and the first strip conductor 10 through the through holes 113 formed in the first strip conductor 10 and the second strip conductor 20, respectively. The second strip conductor 20 is connected.
In addition, the input / output section capacitance forming conductor 111 disposed below the input / output gaps 62 and 72 is connected to the first input / output line 42 and the second input / output line 52 through the through holes 113 respectively. The input / output line 42 and the second input / output line 52 are connected.

  In addition, the inter-unit cell capacitance forming conductor 112 disposed below the inter-unit cell gap 80 is connected to the first strip conductor 10 via the through holes 113 formed in the first strip conductor 10 and the second strip conductor 20, respectively. And connected to the second strip conductor 20.

Next, the operation of the directional coupler according to Embodiment 7 of the present invention will be described.
In the directional coupler according to Embodiment 7 of the present invention, similarly to the directional coupler according to Embodiment 2 described above, a magnetic wall or an electric wall is assumed along the cross section BB ′ serving as a symmetry plane. The equivalent circuits at that time are the equivalent circuits shown in FIGS.

Therefore, similarly to the directional coupler according to the second embodiment described above, the phase constant β ^e during the even mode operation and the phase constant β ^o during the odd mode operation can be changed to translate, Since the amount of the parallel movement can be increased, the difference in the phase constant β ⁱ is increased, resulting in tight coupling and forward coupling. Further, since there is no band gap in both the even mode operation and the odd mode operation, a wide band is obtained. In addition, as compared with a general directional coupler using a right-handed line, if the amount of coupling is the same, the size can be greatly reduced.

As described above, according to the seventh embodiment, the same effect as in the second embodiment can be obtained.
Further, in the directional coupler according to Embodiment 7 of the present invention, the input / output gaps 61, 62, 71, 72 and the unit are provided by providing the input / output portion capacitance forming conductor 111 and the unit cell capacitance forming conductor 112. The capacitance corresponding to the inter-cell gap 80 is increased, and a directional coupler that is tightly coupled at a lower frequency can be formed.

  In the seventh embodiment, the input / output part capacitance forming conductor 111 and the inter-unit cell capacitance forming conductor 112 are connected to the dielectric substrate 1 below the input / output gaps 61, 62, 71, 72 and the unit cell gap 80, respectively. I explained that it was placed inside. However, the present invention is not limited to this, and is arranged above the input / output gaps 61, 62, 71, 72 or the inter-unit cell gap 80 or in the vicinity of the input / output gaps 61, 62, 71, 72 or the inter-unit cell gap 80. Also good.

Embodiment 8 FIG.
FIG. 17 is a plan view showing a directional coupler according to Embodiment 8 of the present invention. 18 is a cross-sectional view of the directional coupler shown in FIG. 17 cut along the line CC ′. In FIG. 17, the first floating conductor 114 is shown so as to be visible on the surface of the dielectric substrate 1, but this is for easy understanding, and in fact, as shown in FIG. It is formed inside the substrate 1.

17 and 18, the directional coupler includes a first floating conductor 114 in addition to the directional coupler shown in FIG.
The first floating conductor 114 is disposed inside the dielectric substrate 1 below the input / output gaps 61, 62, 71, 72.

Next, the operation of the directional coupler according to Embodiment 8 of the present invention will be described.
In the directional coupler according to Embodiment 8 of the present invention, similarly to the directional coupler according to Embodiment 1 described above, a magnetic wall or an electric wall is assumed along the cross section BB ′ serving as a symmetry plane. The equivalent circuits at that time are the equivalent circuits shown in FIGS.

Therefore, similarly to the directional coupler according to the first embodiment described above, the phase constant β ^e during the even mode operation and the phase constant β ^o during the odd mode operation can be changed so as to translate, Since the amount of the parallel movement can be increased, the difference in the phase constant β ⁱ is increased, resulting in tight coupling and forward coupling. Further, since there is no band gap in both the even mode operation and the odd mode operation, a wide band is obtained. Further, as compared with a general directional coupler using a right-handed line, if the amount of coupling is the same, the size can be greatly reduced.

As described above, according to the eighth embodiment, the same effect as in the first embodiment can be obtained.
Further, in the directional coupler according to Embodiment 8 of the present invention, by providing the first floating conductor 114, the capacitance corresponding to the input / output gaps 61, 62, 71, 72 increases, and at a lower frequency. A tightly coupled directional coupler can be constructed.
A directional coupler according to Embodiment 8 of the present invention includes a first floating conductor 114 and a first strip conductor 10 or a second strip conductor 20 (first input / output line 42 or second input / output line 52). Since it is not necessary to form a through hole for connecting the two, a directional coupler according to Embodiment 7 using the through hole 113 can be easily manufactured.

Embodiment 9 FIG.
FIG. 19 is a plan view showing a directional coupler according to Embodiment 9 of the present invention. FIG. 20 is a cross-sectional view of the directional coupler shown in FIG. 19 cut along the line CC ′. In FIG. 19, the first floating conductor 114 and the second floating conductor 115 are shown so as to be visible on the surface of the dielectric substrate 1, but this is for ease of understanding. As shown in FIG. 2, the dielectric substrate 1 is formed inside.

19 and 20, the directional coupler includes a first floating conductor 114 and a second floating conductor 115 in addition to the directional coupler shown in FIG.
The first floating conductor 114 is disposed inside the dielectric substrate 1 below the input / output gaps 61, 62, 71, 72. The second floating conductor 115 is disposed inside the dielectric substrate 1 below the unit cell gap 80.

Next, the operation of the directional coupler according to Embodiment 9 of the present invention will be described.
In the directional coupler according to Embodiment 9 of the present invention, similarly to the directional coupler according to Embodiment 2 described above, a magnetic wall or an electric wall is assumed along the cross-section BB ′ serving as a symmetry plane. The equivalent circuits at that time are the equivalent circuits shown in FIGS.

Therefore, similarly to the directional coupler according to the second embodiment described above, the phase constant β ^e during the even mode operation and the phase constant β ^o during the odd mode operation can be changed to translate, Since the amount of the parallel movement can be increased, the difference in the phase constant β ⁱ is increased, resulting in tight coupling and forward coupling. Further, since there is no band gap in both the even mode operation and the odd mode operation, a wide band is obtained. Further, as compared with a general directional coupler using a right-handed line, if the amount of coupling is the same, the size can be greatly reduced.

As described above, according to the ninth embodiment, the same effect as in the second embodiment can be obtained.
Further, the directional coupler according to Embodiment 9 of the present invention is a side coupling portion in which the first strip conductor and the second strip conductor are side-coupled to the directional coupler according to Embodiment 8 described above. Since the (coupled line portion) is long, more tight coupling can be achieved.

  In the directional coupler according to Embodiment 9 of the present invention, the first floating conductor 114 and the second floating conductor 115 are provided, so that the input / output gaps 61, 62, 71, 72 and the unit cell gap 80 are provided. The capacitance corresponding to 1 increases, and a directional coupler that is tightly coupled at a lower frequency can be formed.

  The directional coupler according to Embodiment 9 of the present invention includes a first floating conductor 114 or a second floating conductor 115 and a first strip conductor 10 or a second strip conductor 20 (first input / output line 42 or second Since it is not necessary to form a through hole for connecting the input / output line 52), it can be easily manufactured as compared with the directional coupler according to the seventh embodiment using the through hole 113.

  In the ninth embodiment, the directional coupler is configured by cascading three unit cells 100a. However, the present invention is not limited to this, and two or four or more unit cells 100a may be cascaded. Good.

Embodiment 10 FIG.
FIG. 21 is a plan view showing a directional coupler according to Embodiment 10 of the present invention.
The directional coupler shown in FIG. 21 is obtained by changing the interval between unit cell gaps 80 in the directional coupler shown in FIG. Specifically, the interval between the unit cell gaps 80 is set to approximately twice the interval between the input / output gaps 61, 62, 71, 72.

Next, the operation of the directional coupler according to Embodiment 10 of the present invention will be described.
FIG. 22 is a circuit diagram showing an equivalent circuit when a magnetic wall or an electric wall is assumed along the line BB ′ of the directional coupler shown in FIG.
22 includes a unit cell 100a and first input / output lines 41 and 42 closer to the first strip conductor 10 than the cross section BB ′.

  For example, in the even mode operation of the directional coupler, this equivalent circuit includes a plurality of transmission line models 101, capacitors 106 and inductors 103 connected in series, and one end connected in parallel between the inductors 103 and the other end connected to the other end. It is represented using a capacitor 104 and an inductor 105 connected to ground.

Here, since the two capacitors 106 corresponding to the unit cell gap 80 are continuously connected in series, the capacitor which is about ½ times the capacitance of the capacitor 106 corresponding to the input / output gaps 61 and 62. 107 can be substituted. The equivalent circuit at this time is the equivalent circuit shown in FIG.
On the other hand, since the interval between the unit cell gaps 80 is set to be approximately twice the interval between the input / output gaps 61 and 62, the capacitance corresponding to the unit cell gap 80 is equal to the input / output gaps 61 and 62. It is about ½ times the capacitance corresponding to.

Therefore, the directional coupler according to Embodiment 10 of the present invention has a configuration closer to the equivalent circuit shown in FIG. 23, so that it is possible to realize a good reflection characteristic with impedance matching.
That is, according to the tenth embodiment, the same effect as in the second embodiment can be obtained, and a directional coupler having good reflection characteristics can be obtained.

  In the tenth embodiment, three unit cells 100a are connected in cascade to form a directional coupler. However, the present invention is not limited to this, and two or more unit cells 100a may be connected in cascade. Good.

Embodiment 11 FIG.
FIG. 24 is a plan view showing a directional coupler according to Embodiment 11 of the present invention.
The directional coupler shown in FIG. 24 is obtained by changing the shapes of the input / output gaps 61, 62, 71, 72 and the unit cell gap 80 in the directional coupler shown in FIG. Specifically, the input / output gaps 61, 62, 71, 72 and the inter-unit cell gap 80 are interdigital capacitors.

  The size of the interdigital capacitor constituting the unit cell gap 80 is such that the capacitance corresponding to the input / output gaps 61, 62, 71, 72 is about twice the capacitance corresponding to the unit cell gap 80. Is set to about ½ times the size of the interdigital capacitor constituting the input / output gaps 61, 62, 71, 72.

Next, the operation of the directional coupler according to Embodiment 11 of the present invention will be described.
In the directional coupler according to Embodiment 11 of the present invention, the capacitance corresponding to the input / output gaps 61, 62, 71, 72 can be approximately double the capacitance corresponding to the unit cell gap 80. The same effects as those in the tenth embodiment described above can be obtained.
That is, according to the eleventh embodiment, the same effects as those of the second embodiment can be obtained, and good reflection characteristics with impedance matching can be realized.

  In the eleventh embodiment, the directional coupler is configured by cascading three unit cells 100a. However, the present invention is not limited to this, and two or four or more unit cells 100a may be cascaded. Good.

Embodiment 12 FIG.
FIG. 25 is a plan view showing a directional coupler according to Embodiment 12 of the present invention. In FIG. 25, the first floating conductor 114 and the second floating conductor 115 are illustrated so as to be visible on the surface of the dielectric substrate 1, but this is for ease of understanding. It is formed inside the substrate 1.

  The directional coupler shown in FIG. 25 is obtained by changing the area of the first floating conductor 114 in the directional coupler shown in FIG. Specifically, the first floating conductor 114 is connected to the first input / output line so that the capacitance corresponding to the input / output gaps 61, 62, 71, 72 is approximately twice the capacitance corresponding to the unit cell gap 80. 41, 42, the second input / output lines 51, 52, and the area overlapping the unit cell 100a are set to be approximately twice the area of the portion where the second floating conductor 115 overlaps the unit cell 100a. That is, the unit cell 100a is connected in cascade with the first input / output lines 41 and 42 and the second input / output lines 51 and 52 with a capacitance that is approximately twice the capacitance of the unit cells 100a connected in cascade.

Next, the operation of the directional coupler according to Embodiment 12 of the present invention will be described.
In the directional coupler according to Embodiment 12 of the present invention, the capacitance corresponding to the input / output gaps 61, 62, 71, 72 can be approximately double the capacitance corresponding to the unit cell gap 80. The same effects as those in the tenth embodiment described above can be obtained.
That is, according to the twelfth embodiment, the same effects as those of the ninth embodiment can be obtained, and good reflection characteristics with impedance matching can be realized.

  In the twelfth embodiment, the directional coupler is configured by cascading three unit cells 100a. However, the present invention is not limited to this, and two or four or more unit cells 100a may be cascaded. Good.

Embodiment 13 FIG.
FIG. 26 is a plan view showing a directional coupler according to Embodiment 13 of the present invention.
The directional coupler according to Embodiment 13 of the present invention is configured using a microstrip line.

26, the directional coupler includes a third strip conductor 30e instead of the third strip conductor 30a and the through hole 31 shown in FIG.
The third strip conductor 30e connects the first strip conductor 10 and the second strip conductor 20, and is formed so as to cross the first strip conductor 10 and the second strip conductor 20 and extend outward.

Here, the electrical length of the open stub formed by the portion of the third strip conductor 30e that intersects with the first strip conductor 10 or the second strip conductor 20 and extends outward is 90 degrees or more and 180 degrees indicating inductivity, respectively. It is set as follows. Also, a combination of the first strip conductor 10, the second strip conductor 20, and the third strip conductor 30e is referred to as a unit cell 100e.
Since other configurations are the same as those in the first embodiment, description thereof is omitted.

Next, the operation of the directional coupler according to Embodiment 13 of the present invention will be described.
In the directional coupler according to Embodiment 13 of the present invention, similarly to the directional coupler according to Embodiment 1 described above, a magnetic wall or an electric wall is assumed along the cross section BB ′ serving as a symmetry plane. can do.

  Note that the electrical lengths of the open stubs formed by the third strip conductor 30e that intersects with the first strip conductor 10 or the second strip conductor 20 and extends outward are 90 degrees or more and 180 degrees or less, respectively. The electric potential is always 0 at the portion where the electrical length is about 90 degrees inside from the end of the strip conductor 10 or the second strip conductor 20.

  That is, in the directional coupler according to Embodiment 13 of the present invention, the portion of the third strip conductor 30e that extends outwardly across the first strip conductor 10 or the second strip conductor 20 is the same as that of the above-described embodiment. In the directional coupler according to No. 3, the function similar to that of the short stub formed by the third strip conductor 30b and the through hole 31 in a portion extending outwardly intersecting the first strip conductor 10 or the second strip conductor 20 have.

Therefore, the equivalent circuits of the directional coupler according to Embodiment 13 of the present invention are the equivalent circuits shown in FIGS.
From this, in the directional coupler according to Embodiment 13 of the present invention, similarly to the directional coupler according to Embodiment 3 described above, the phase constant β ^e during the even mode operation and the phase constant β ^e during the odd mode operation are used. Since the phase constant β ^o can be changed so as to move in parallel and the amount of the parallel movement can be increased, the difference in the phase constant β ⁱ becomes large, which results in tight coupling and forward coupling. Further, since there is no band gap in both the even mode operation and the odd mode operation, a wide band is obtained.

As described above, according to the thirteenth embodiment, the same effect as in the third embodiment can be obtained.
In addition, the directional coupler according to Embodiment 13 of the present invention does not require the formation of a through hole that short-circuits the third strip conductor 30e to the ground conductor 2, and therefore relates to Embodiment 3 using the through hole 31. Compared to a directional coupler, it can be easily manufactured.

Embodiment 14 FIG.
FIG. 27 is a plan view showing a directional coupler according to Embodiment 14 of the present invention.
The directional coupler shown in FIG. 27 is configured by arranging three unit cells 100e in series in the directional coupler shown in FIG.

  Input / output gaps 61 and 62 are formed between the first strip conductor 10 and the first input / output lines 41 and 42, respectively. Input / output gaps 71 and 72 are formed between the second strip conductor 20 and the second input / output lines 51 and 52, respectively. A unit cell gap 80 is formed between the first strip conductors 10 and between the second strip conductors 20. That is, the unit cells 100e are connected in cascade via the inter-unit cell gap 80.

Next, the operation of the directional coupler according to Embodiment 14 of the present invention will be described.
The directional coupler according to Embodiment 14 of the present invention, like the directional coupler according to Embodiment 13 described above, has a phase constant β ^e during even mode operation and a phase constant β ^o during odd mode operation. Can be changed so as to translate, and the amount of translation can be increased, so that the difference in the phase constant β ⁱ becomes large, which results in tight coupling and forward coupling. Further, since there is no band gap in both the even mode operation and the odd mode operation, a wide band is obtained. In addition, as compared with a general directional coupler using a right-handed line, if the amount of coupling is the same, the size can be greatly reduced.

As described above, according to the fourteenth embodiment, the same effect as in the thirteenth embodiment can be obtained.
Furthermore, the directional coupler according to Embodiment 14 of the present invention is a side coupling portion in which the first strip conductor and the second strip conductor are side-coupled to the directional coupler according to Embodiment 13 described above. Since the (coupled line portion) is long, more tight coupling can be achieved.

  In the fourteenth embodiment, the directional coupler is configured by cascading three unit cells 100e. However, the present invention is not limited to this, and two or four or more unit cells 100e may be cascaded. Good.

Embodiment 15 FIG.
FIG. 28 is a plan view showing a directional coupler according to Embodiment 15 of the present invention.
28, the directional coupler includes a third strip conductor 30f instead of the third strip conductor 30e shown in FIG.

  The third strip conductor 30f connects the first strip conductor 10 and the second strip conductor 20, and from the middle between the first strip conductor 10 and the second strip conductor 20, the third conductor portion 13 and the third conductor portion. It has a T-branch portion that branches in 23 directions (right direction in the figure).

Here, the electrical length from the connection point of the first strip conductor 10 or the second strip conductor 20 and the third strip conductor 30f to the T branch portion is set to 0 degrees or more and 90 degrees or less, and the T branch section to the T branch section. The electrical length to the tip of is set to 0 degree or more and 90 degrees or less. That is, the electrical length from the connection point between the first strip conductor 10 or the second strip conductor 20 and the third strip conductor 30f to the tip of the T-branch portion is set to 90 degrees or more and 180 degrees or less indicating inductivity, respectively. Yes. Also, a combination of the first strip conductor 10, the second strip conductor 20, and the third strip conductor 30f is referred to as a unit cell 100f.
Other configurations are the same as those in the thirteenth embodiment, and a description thereof will be omitted.

Next, the operation of the directional coupler according to Embodiment 15 of the present invention will be described.
In the directional coupler according to Embodiment 15 of the present invention, similarly to the directional coupler according to Embodiment 1 described above, a magnetic wall or an electric wall is assumed along the cross-section BB ′ serving as a symmetry plane. can do.

  The electrical length from the connection point of the first strip conductor 10 or the second strip conductor 20 and the third strip conductor 30f to the tip of the T branch portion is 90 degrees or more and 180 degrees or less, respectively. There is a part where the potential is always 0 between the part where the tip of the part is open.

That is, the third strip conductor 30f of the directional coupler according to Embodiment 15 of the present invention is formed of the third strip conductor 30c and the through hole 31 in the directional coupler according to Embodiment 5 described above. It has the same function as the short stub.
Therefore, the equivalent circuits of the directional coupler according to Embodiment 15 of the present invention are equivalent circuits shown in FIGS.

From this, in the directional coupler according to Embodiment 15 of the present invention, similarly to the directional coupler according to Embodiment 5 described above, the phase constant β ^e during the even mode operation and the phase constant β ^e during the odd mode operation are used. Since the phase constant β ^o can be changed so as to move in parallel and the amount of the parallel movement can be increased, the difference in the phase constant β ⁱ becomes large, which results in tight coupling and forward coupling. Further, since there is no band gap in both the even mode operation and the odd mode operation, a wide band is obtained.

As described above, according to the fifteenth embodiment, the same effect as in the fifth embodiment can be obtained.
In addition, the directional coupler according to Embodiment 15 of the present invention does not require the formation of a through hole that short-circuits the third strip conductor 30f to the ground conductor 2, and thus relates to Embodiment 5 using the through hole 31. Compared to a directional coupler, it can be easily manufactured.

Embodiment 16 FIG.
FIG. 29 is a plan view showing a directional coupler according to Embodiment 16 of the present invention.
The directional coupler shown in FIG. 29 is configured by arranging three unit cells 100f in series in the directional coupler shown in FIG.

  Input / output gaps 61 and 62 are formed between the first strip conductor 10 and the first input / output lines 41 and 42, respectively. Input / output gaps 71 and 72 are formed between the second strip conductor 20 and the second input / output lines 51 and 52, respectively. A unit cell gap 80 is formed between the first strip conductors 10 and between the second strip conductors 20. That is, the unit cells 100f are connected in cascade through the inter-unit cell gap 80.

Next, the operation of the directional coupler according to Embodiment 16 of the present invention will be described.
The directional coupler according to Embodiment 16 of the present invention, like the directional coupler according to Embodiment 15 described above, has a phase constant β ^e during even mode operation and a phase constant β ^o during odd mode operation. Can be changed so as to translate, and the amount of translation can be increased, so that the difference in the phase constant β ⁱ becomes large, which results in tight coupling and forward coupling. Further, since there is no band gap in both the even mode operation and the odd mode operation, a wide band is obtained. In addition, as compared with a general directional coupler using a right-handed line, if the amount of coupling is the same, the size can be greatly reduced.

As described above, according to the sixteenth embodiment, the same effect as in the fifteenth embodiment can be obtained.
Further, the directional coupler according to Embodiment 16 of the present invention is a side coupling portion in which the first strip conductor and the second strip conductor are side-coupled to those of the directional coupler according to Embodiment 15 described above. Since the (coupled line portion) is long, more tight coupling can be achieved.

  In the sixteenth embodiment, the directional coupler is configured by cascading three unit cells 100f. However, the present invention is not limited to this, and two or four or more unit cells 100f may be cascaded. Good.

  In the sixteenth embodiment, the third strip conductor 30f has been described as having a T-branch. However, the present invention is not limited to this, and as shown in FIG. 30, the third strip conductor 30 g is further provided at the end of the T branch portion formed in the middle between the first strip conductor 10 and the second strip conductor 20. You may have.

Embodiment 17. FIG.
FIG. 31 is a plan view showing a directional coupler according to Embodiment 17 of the present invention. In FIG. 31, the first floating conductor 114 and the third floating conductor 116 are illustrated so as to be visible on the surface of the dielectric substrate 1, but this is for ease of understanding. It is formed inside the substrate 1.

In FIG. 31, this directional coupler includes a third floating conductor 116 in addition to the directional coupler shown in FIG.
The third floating conductor 116 is disposed inside the dielectric substrate 1 below the input / output gaps 61, 62, 71, 72.

Next, the operation of the directional coupler according to Embodiment 17 of the present invention will be described.
In the directional coupler according to Embodiment 17 of the present invention, similarly to the directional coupler according to Embodiment 1 described above, a magnetic wall or an electric wall is assumed along the cross-section BB ′ serving as a symmetry plane. The equivalent circuits at that time are the equivalent circuits shown in FIGS.

  Here, since the third floating conductor 116 exists on the cross section BB ′, the third floating conductor 116 acts as a floating conductor in the even mode operation, but the cross section BB ′ is an electric wall in the odd mode operation. Since it is connected to the ground conductor 2, it acts as a ground conductor. Therefore, the values of the capacitors 102a and 102b in the equivalent circuit during the even mode operation are larger than the values of the capacitors 202a and 202b in the equivalent circuit during the odd mode operation, and the capacitor 104 in the equivalent circuit during the even mode operation. The value is smaller than the value of the capacitor 204 in the equivalent circuit during the odd mode operation.

Therefore, by providing the third floating conductor 116, the values of all elements on the equivalent circuit can be changed during the even mode operation and the odd mode operation, so that the circuit design is facilitated.
Similarly to the directional coupler according to the first embodiment described above, the phase constant β ^e during the even mode operation and the phase constant β ^o during the odd mode operation can be changed so as to translate, Since the amount of the parallel movement can be increased, the difference in the phase constant β ⁱ is increased, resulting in tight coupling and forward coupling. Further, since there is no band gap in both the even mode operation and the odd mode operation, a wide band is obtained. In addition, as compared with a general directional coupler using a right-handed line, if the amount of coupling is the same, the size can be greatly reduced.

  As described above, according to the seventeenth embodiment, it is possible to obtain a directional coupler that can obtain the same effects as those of the eighth embodiment and can easily design a circuit.

Embodiment 18 FIG.
FIG. 32 is a plan view showing a directional coupler according to Embodiment 18 of the present invention. In FIG. 32, the first floating conductor 114, the second floating conductor 115, the third floating conductor 116, and the fourth floating conductor 117 are shown to be visible on the surface of the dielectric substrate 1, but this is understood. In order to facilitate, it is actually formed inside the dielectric substrate 1.

32, the directional coupler includes a third floating conductor 116 and a fourth floating conductor 117 in addition to the directional coupler shown in FIG.
The third floating conductor 116 is disposed inside the dielectric substrate 1 below the input / output gaps 61, 62, 71, 72. The fourth floating conductor 117 is disposed inside the dielectric substrate 1 below the unit cell gap 80.

Next, the operation of the directional coupler according to Embodiment 18 of the present invention will be described.
The directional coupler according to Embodiment 18 of the present invention, like the directional coupler according to Embodiment 17 described above, has a phase constant β ^e during even mode operation and a phase constant β ^o during odd mode operation. Can be changed so as to translate, and the amount of translation can be increased, so that the difference in the phase constant β ⁱ becomes large, which results in tight coupling and forward coupling. Further, since there is no band gap in both the even mode operation and the odd mode operation, a wide band is obtained. In addition, as compared with a general directional coupler using a right-handed line, if the amount of coupling is the same, the size can be greatly reduced.

As described above, according to the eighteenth embodiment, the same effect as in the seventeenth embodiment can be obtained.
In addition, the directional coupler according to Embodiment 18 of the present invention is a side coupling portion where the first strip conductor and the second strip conductor are side-coupled to the directional coupler according to Embodiment 17 described above. Since the (coupled line portion) is long, more tight coupling can be achieved.

  In the eighteenth embodiment, three unit cells 100a are connected in cascade to form a directional coupler. However, the present invention is not limited to this, and two or more unit cells 100a may be connected in cascade. Good.

  DESCRIPTION OF SYMBOLS 1 Dielectric board | substrate, 2 Ground conductor, 10 1st strip conductor, 20 2nd strip conductor, 30a-30g 3rd strip conductor, 31 Through hole (short-circuit means), 41, 42 1st input / output line, 51, 52 1st 2 input / output lines, 100a to 100g unit cell, 114 first floating conductor, 115 second floating conductor, 116 third floating conductor, 117 fourth floating conductor.

Claims (13)

A first strip conductor formed on a dielectric substrate;
A second strip conductor formed on the dielectric substrate so as to face the first strip conductor;
A third strip conductor connecting the first strip conductor and the second strip conductor;
A ground conductor formed on the dielectric substrate separately from the first strip conductor, the second strip conductor, and the third strip conductor;
Short-circuit means for short-circuiting the third strip conductor to a ground potential;
A pair of first input / output lines formed adjacent to both ends of the first strip conductor;
A pair of second input / output lines formed in proximity to both ends of the second strip conductor,
In the side coupling portion where the first strip conductor and the second strip conductor are side-coupled, the distance between the first strip conductor and the second strip conductor is from the first strip conductor to the ground conductor. And the distance from the second strip conductor to the ground conductor, whichever is shorter, is less than twice the directional coupler.   The directional coupler according to claim 1, wherein the short-circuit means is a connection conductor that connects the third strip conductor and the ground conductor.   The directional coupler according to claim 2, wherein the connection conductor is formed at a central portion of the third strip conductor.   The directional coupler according to claim 2, wherein the connection conductor is formed at both ends of the third strip conductor.   2. The direction according to claim 1, wherein the short-circuit unit includes a branch portion branched from a central portion of the third strip conductor, and a connection conductor connecting the branch portion and the ground conductor. Sex coupler.   The directional coupler according to claim 1, wherein the short-circuit means is an open stub formed to extend from both ends of the third strip conductor.   2. The directional coupler according to claim 1, wherein the short-circuit means is a branch portion branched from a central portion of the third strip conductor.   In the vicinity of the portion where the first strip conductor and the first input / output line face each other, and in the vicinity of the portion where the second strip conductor and the second input / output line face each other, no first conductor is connected. The directional coupler according to any one of claims 1 to 7, wherein one floating conductor is provided.   A third floating conductor that is not connected to any conductor is provided in the vicinity of a portion where the first strip conductor and the second strip conductor oppose the first input / output line and the second input / output line. The directional coupler according to any one of claims 1 to 8, wherein the directional coupler is any one of claims 1 to 8. In the unit cell composed of the first strip conductor, the second strip conductor, and the third strip conductor, the end portions of the first strip conductor face each other, and the end portions of the second strip conductor face each other. The directional coupler according to any one of claims 1 to 9, wherein a plurality of the directional couplers are arranged side by side.   The directional coupler according to claim 10, wherein the unit cell includes the short-circuit unit.   A second floating conductor that is not connected to any conductor is provided in the vicinity of the portion where the end portions of the first strip conductor face each other and in the vicinity of the portion where the end portions of the second strip conductor face each other. 12. A directional coupler according to claim 10 or claim 11 characterized in that it is characterized in that:   The fourth floating conductor that is not connected to any conductor is provided in the vicinity of a portion where the step portions of the first strip conductors and the end portions of the second strip conductors face each other. The directional coupler according to any one of claims 12 to 13.

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