WO2016157375A1

WO2016157375A1 - Phase shifting circuit and antenna device

Info

Publication number: WO2016157375A1
Application number: PCT/JP2015/059960
Authority: WO
Inventors: 誠司嘉戸
Original assignee: 日立金属株式会社
Priority date: 2015-03-30
Filing date: 2015-03-30
Publication date: 2016-10-06

Abstract

Provided are: a phase shifting circuit whereby size can be reduced, while being capable of increasing a phase shift quantity, and excellent voltage standing wave ratio (VSWR) can be obtained in a wide frequency band; and an antenna device. A phase shifting circuit 1 is provided with a signal conductor 2 that transmits signals, and a dielectric body 3 that is disposed such that the dielectric body and the signal conductor 2 overlap each other, and the phase shifting circuit changes the phase of the signals by changing the area of an overlapping section 5 where the signal conductor 2 and the dielectric body 3 overlap each other. The phase shifting circuit is also provided with a transformer unit 7, which is provided on dielectric body 3 end portions on the signal input side and the signal output side, and in which a characteristic impedance value is larger than the characteristic impedance value of the overlapping section 5, and is smaller than the characteristic impedance value of a non-overlapping section 6 where the signal conductor 2 and the dielectric body 3 do not overlap each other.

Description

Phase shift circuit and antenna device

The present invention relates to a phase shift circuit and an antenna device.

There is Patent Document 1 as a conventional phase shift circuit.

In the phase shift circuit described in Patent Document 1, a plurality of intersections where the signal conductor and the dielectric overlap along the longitudinal direction of the phase shift circuit are provided, and the dielectric is moved in the longitudinal direction of the phase shift circuit. The area where the signal conductor and the dielectric overlap is changed at the intersection, and the phase of the signal transmitted through the signal conductor is changed.

JP 2014-158188 A Japanese Patent No. 4745213

However, the phase shift circuit described in Patent Document 1 has a problem that it is necessary to increase the number of intersections in order to increase the amount of phase shift, and the total length may be increased.

Further, in the phase shift circuit described in Patent Document 1, in order to obtain a good VSWR (voltage standing wave ratio) characteristic in a wide frequency band, it is necessary to adjust the shape of the dielectric, the interval between intersections, and the like. . At this time, depending on the shape of the dielectric after adjustment, there is a problem that the linearity of the drive amount and the phase shift amount is lowered, and the movement control of the dielectric may be complicated.

Accordingly, the present invention provides a phase shift circuit and an antenna device that can be made compact while being able to increase the amount of phase shift, and that can obtain good VSWR characteristics in a wide frequency band. With the goal.

In order to solve the above problems, the present invention includes a signal conductor that transmits a signal and a dielectric disposed so as to overlap the signal conductor, and the signal conductor and the dielectric overlap each other. A phase-shift circuit that changes the phase of the signal by changing the area of the part, provided at the input side and output side ends of the signal of the dielectric, wherein the characteristic impedance value is the overlapping part A phase shift circuit having a transformer portion that is larger than a characteristic impedance value of the non-overlapping portion where the signal conductor and the dielectric do not overlap with each other.

The present invention also provides an antenna device including the phase shift circuit for the purpose of solving the above-described problems.

According to the present invention, it is possible to provide a phase shift circuit and an antenna device that can be made compact while being able to increase the amount of phase shift and that can obtain good VSWR characteristics in a wide frequency band.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the phase shift circuit which concerns on one embodiment of this invention, (a) is the top view which abbreviate | omitted one ground conductor, (b) is the sectional view on the AA line of (a). FIG. 2 is a graph showing a result of simulating VSWR (voltage standing wave ratio) characteristics in the phase shift circuit of FIG. 1. FIG. 2 is a graph showing the result of simulating the relationship between drive amount and phase shift in the phase shift circuit of FIG. 1. It is a schematic block diagram of the antenna apparatus using the phase shift circuit of FIG. (A), (b) is sectional drawing of the phase shift circuit which concerns on one modification of this invention. It is the top view which abbreviate | omitted one ground conductor of the phase shift circuit which concerns on one modification of this invention. (A) is a plan view in which one ground conductor of a phase shift circuit according to a modification of the present invention is omitted, (b) is a cross-sectional view taken along line BB of (a), and (c) is a phase shift of (a). It is a top view at the time of comprising a phase circuit in multistage. It is the top view which abbreviate | omitted one ground conductor of the phase shift circuit which concerns on one modification of this invention. (A) is the top view which abbreviate | omitted one ground conductor of the phase shift circuit based on one modification of this invention, (b) is CC sectional view taken on the line of (a). FIG. 10 is a graph showing a result of simulating a VSWR (voltage standing wave ratio) characteristic in the phase shift circuit of FIG. 9.

[Embodiment]
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a diagram showing a phase shift circuit according to the present embodiment, in which (a) is a plan view in which one ground conductor is omitted, and (b) is a cross-sectional view.

As shown in FIGS. 1A and 1B, the phase shift circuit 1 includes a signal conductor 2 that transmits a signal, a dielectric 3 that is disposed so as to overlap the signal conductor 2, and a signal conductor of the dielectric 3. 2 and a ground conductor 4 disposed on the opposite side.

The signal conductor 2 is made of a plate-like member made of a good electric conductor. In the present embodiment, the signal conductor 2 is composed of two straight portions 2a arranged in parallel and a connecting portion 2b that connects the tip portions of the straight portions 2a (right ends in FIG. 1). As a whole, it is formed in a U-shape rotated 90 ° counterclockwise in plan view. The connecting portion between the straight line portion 2a and the connecting portion 2b has a chamfered shape.

In the present embodiment, a plate-like member made of a good electrical conductor is used as the signal conductor 2, but the signal conductor 2 is not limited to this, and the signal conductor 2 is a wiring pattern formed on both surfaces of a dielectric substrate made of glass epoxy or the like. In addition, when a film-like material is used as the dielectric, it may be constituted by a wiring pattern formed on one surface of the film-like substrate.

The ground conductor 4 is made of a plate-like member made of a good electrical conductor. In the present embodiment, the phase shift circuit 4 has a triplate structure in which two ground conductors 4 are provided so as to sandwich the signal conductor 2 from above and below. Hereinafter, the ground conductor 4 disposed above the signal conductor 2 (upper side in FIG. 1B) is referred to as a first ground conductor 4a and below the signal conductor 2 (lower side in FIG. 1B). The arranged ground conductor 4 is referred to as a second ground conductor 4b. In addition, in Fig.1 (a), the top view when the 1st ground conductor 4a is abbreviate | omitted is shown.

The dielectric 3 is made of a rectangular plate-like member in plan view. The material of the dielectric 3 is not particularly limited, but it is desirable to use a material having a dielectric constant as large as possible in order to increase the amount of phase shift.

In the present embodiment, the dielectric 3 includes a first dielectric 3a and a second dielectric 3b that are disposed so as to sandwich the signal conductor 2 from above and below. The first dielectric 3a is disposed between the signal conductor 2 and the first ground conductor 4a, and the second dielectric 3b is disposed between the signal conductor 2 and the second ground conductor 4b. Both

dielectrics

3a and 3b are arranged apart from the signal conductor 2 and the ground conductor 4 so as not to be affected by the electric field formed in the immediate vicinity of the signal conductor 2 and the ground conductor 4. That is, the first dielectric 3a is disposed away from the signal conductor 2 and the first ground conductor 4a, and the second dielectric 3b is disposed away from the signal conductor 2 and the second ground conductor 4b.

Both

dielectrics

3a and 3b are connected by a connecting member (not shown). The

dielectrics

3a and 3b are configured to be movable in the left-right direction in FIG. 1 by a moving mechanism (not shown) such as a DC motor.

Hereinafter, a portion where the signal conductor 2 and the dielectric 3 overlap in the phase shift circuit 1 is referred to as an overlapping portion 5, and a portion where the signal conductor 2 and the dielectric 3 do not overlap is referred to as a non-overlapping portion 6. The non-overlapping portion 6 is a portion where the signal conductor 2 and the ground conductor 4 face each other with an air layer interposed therebetween.

In the phase shift circuit 1, the phase of the signal transmitted through the signal conductor 2 is changed by moving the dielectric 3 by the moving means and changing the area of the overlapping portion 5 where the signal conductor 2 and the dielectric 3 overlap. It is configured as follows. In the phase shift circuit 1, the phase of the signal is delayed as the area of the overlapping portion 5 is increased, and the phase of the signal is advanced as the area of the overlapping portion 5 is decreased. Therefore, in the case of FIG. 1, by moving the dielectric 3 from a certain reference position to the left side (the base end side of the parallel part 2a), the phase of the signal is delayed from the phase at the reference position, and the right side ( The phase of the signal can be advanced from the phase at the reference position by moving the dielectric to the tip side of the parallel part 2a and the connection part 2b side). The moving range of the dielectric 3 is set in advance. In the phase shift circuit 1, the phase of the signal is changed by changing the area of the overlapping portion 5 by moving the dielectric 3 within the moving range. It is configured.

Now, in the phase shift circuit 1 according to the present embodiment, a transformer for matching impedance between the overlapping portion 5 and the non-overlapping portion 6 at the signal input side and output side ends of the dielectric 3. Part 7 is provided. Here, the signal input side and output side end portions of the dielectric 3 are portions in the vicinity of the boundary between the overlapping portion 5 and the non-overlapping portion 6 in the dielectric 3, and the signal input side and output side The signal conductor 2 (parallel portion 2 a) is an edge portion of the dielectric 3 in the vicinity of a portion extending from the overlapping portion 5 to the non-overlapping portion 6. In this embodiment, the transformer section 7 is formed by processing a part of the dielectric 3. However, the transformer section 7 is not a part of the dielectric 3 and is separate from the dielectric 3. Handle as a member. That is, a portion where the transformer portion 7 and the signal conductor 2 overlap is not included in the overlap portion 5.

In the present embodiment, since the input side and output side signal conductors 2 (parallel portions 2a) extend in the same direction (left direction in the figure), the extension side (left side in the figure) of the signal conductor 2 in the dielectric 3 is shown. A common transformer section 7 is formed on the input side and the output side. The transformer section 7 may be provided separately on the signal input side and the output side. The transformer section 7 is provided on both the first dielectric 3a and the second dielectric 3b, respectively.

Also, the transformer section 7 is configured to always be located at the signal input side and output side ends of the dielectric 3 when the dielectric 3 is moved within the set moving range. Here, the transformer section 7 is formed at the end of the dielectric 3 on the extending side of the signal conductor 2, and the phase shift is performed so that the dielectric 3 is moved along the extending direction of the signal conductor 2. Since the circuit 1 is configured, the transformer unit 7 is always located at the signal input side and output side ends of the dielectric 3 even when the dielectric 3 is moved in the horizontal direction in the figure. It will be.

The transformer section 7 is set such that the characteristic impedance value is larger than the characteristic impedance value of the overlapping section 5 and smaller than the characteristic impedance value of the non-overlapping section 6.

In the present embodiment, the transformer section 7 is configured to be a λ / 4 transformer corresponding to the center frequency of the signal transmitted by the signal conductor 2. That is, when the wavelength corresponding to the center frequency of the signal transmitted by the signal conductor 2 (effective wavelength in the non-overlapping portion 6) is λg, the transformer section 7 has a length L along the signal conductor 2 of λg / 4 and the characteristic impedance value is expressed by the following equation (1).
Z = (Za × Zb) ^1/2 (1)
However, Za is set so as to satisfy the characteristic impedance of the overlapping portion 5 Zb: the characteristic impedance of the non-overlapping portion 6 is satisfied.

In the present embodiment, by reducing the thickness of the dielectric 3 at the end of the dielectric 3, the effective dielectric constant between the signal conductor 2 and the ground conductor 4 in the portion where the thickness is reduced is reduced. Thus, the transformer section 7 is configured. That is, in this embodiment, the effective dielectric constant between the signal conductor 2 and the ground conductor 4 in the transformer section 7 is smaller than the effective dielectric constant between the signal conductor 2 and the ground conductor 4 in the overlapping section 5, and the non-overlapping section. 6 is larger than the effective dielectric constant between the signal conductor 2 and the ground conductor 4.

Hereinafter, the dielectric 3 constituting a part of the transformer section 7, that is, the end of the dielectric 3 formed with a small thickness is referred to as a dielectric layer 7a, and the gap between the dielectric layer 7a and the ground conductor 4 is referred to as a dielectric layer 7a. The gap portion is referred to as an air layer 7b. The thickness of the dielectric layer 7a, that is, the ratio of the thickness of the dielectric layer 7a and the air layer 7b is adjusted so that the value of the characteristic impedance in the transformer section 7 satisfies the above formula (1). Is done. For example, when the characteristic impedance of the overlapping part 5 is 21Ω and the characteristic impedance of the non-overlapping part 6 is 50Ω, the characteristic impedance of the transformer part 7 is set to about 32.4Ω.

In FIG. 1, the transformer section 7 is configured such that the dielectric layer 7a is on the signal conductor 2 side and the air layer 7b is on the ground conductor 4 side. However, the present invention is not limited to this, and the dielectric layer 7a is not limited thereto. May be disposed on the ground conductor 4 side and the air layer 7b may be disposed on the signal conductor 2 side. The dielectric layer 7a may be formed in the center in the thickness direction, and the air layers 7b may be formed above and below the dielectric layer 7a. You may comprise so that it may arrange | position.

FIG. 2 shows the result of simulating the VSWR (voltage standing wave ratio) characteristics in the phase shift circuit 1 of FIG.

As shown in FIG. 2, in the phase shift circuit 1, the VSWR is 1.2 or less in the frequency range of about 0.8 GHz to 1.07 GHz, the impedance matching is good, and the good in a wide frequency band. It can be seen that the VSWR characteristic is realized.

FIG. 3 shows the result of simulating the relationship between the drive amount and the phase in the phase shift circuit 1 of FIG. The driving amount is the amount of movement of the derivative 3 in the left-right direction in FIG.

As shown in FIG. 3, in the phase shift circuit 1, the drive amount and the phase have a substantially linear relationship at least when the phase shift amount is between 90 ° and −90 °, and high linearity is obtained. I understand.

Next, an antenna device using the phase shift circuit 1 will be described.

As shown in FIG. 4, the antenna device 41 is distributed by an input terminal 42 to which a high-frequency signal is input, a first distribution line 14a that distributes a signal input to the input terminal 42, and a first distribution line 44a. A second distribution line 44b for further distributing the signal, a third distribution line 44c for further distributing the signal distributed by the second distribution line 44b, an antenna element 43 connected to a terminal portion of the third distribution line 44c, It has. Each distribution line 44a to 44c has a 1-input / 2-output line configuration, and a total of eight antenna elements 43a to 43h are connected to the terminal portion of the third distribution line 44c.

The phase shift circuit 1 is provided between the first distribution line 44a and the second distribution line 44b and between the second distribution line 44b and the third distribution line 44c. Here, a total of six phase shift circuits 1a to 1 are provided at two places between the first distribution line 44a and the second distribution line 44b and at four places between the second distribution line 44b and the third distribution line 44c. 1f is provided.

Phase shift circuits

1a and 1b provided between the first distribution line 44a and the second distribution line 44b,

phase shift circuits

1c and 1d provided between the second distribution line 44b and the third wiring path 44c, and phase shift The

circuits

1e and 1f are used as a pair. When one

phase shift circuit

1a, 1c and 1e of the pair advances the phase by a predetermined phase shift amount, the other

phase shift circuits

1b, 1d and 1f of the pair are the same. The phase is delayed by the amount of phase shift. Here, in the phase shift circuit 1 of each pair of the

phase shift circuits

1a and 1b, the

phase shift circuits

1c and 1d, and the

phase shift circuits

1e and 1f, the phase shift circuit 1 constituting the pair is moved in the moving direction of the dielectric 3. By arranging the two dielectrics 3 so as to be connected and moved together, the phase shift circuit 1 constituting the pair is advanced in phase while the other is delayed in phase. A dynamic phase shift circuit was constructed.

In the antenna device 41, it is possible to adjust the directivity (electric tilt angle) of radio waves radiated from the antenna elements 43a to 43h by changing the phase of the signal by the phase shift circuits 1a to 1f. Although the case where eight antenna elements 43 (43a to 43h) and six phase shift circuits 1 (1a to 1f) are used has been described here, the number of antenna elements 43 and phase shift circuits 1 is an example. It is not limited to the illustrated one.

(Operation and effect of the embodiment)
As described above, in the phase shift circuit 1 according to the present embodiment, the characteristic impedance value provided at the signal input side and output side ends of the dielectric 3 is the value of the characteristic impedance of the overlapping portion 5. A transformer section 7 that is larger and smaller than the characteristic impedance value of the non-overlapping section 6 is provided.

By providing the transformer unit 7, it is possible to match the impedances of the overlapping portion 5 and the non-overlapping portion 6 having different characteristic impedances, and obtain a good VSWR characteristic in a wide frequency band. Moreover, in the phase shift circuit 1, the linearity of the drive amount and the phase shift amount is high, and the movement control of the dielectric 3 is easy.

Further, the phase shift circuit 1 can easily increase the amount of change in the area of the overlapping portion 5, that is, the amount of phase shift, by adjusting the length of the dielectric 3 along the moving direction. Compared to the conventional case where a plurality of intersections are provided along the moving direction of the dielectric 3, the moving distance of the dielectric 3 required to obtain the same area of the overlapping portion 5 is reduced, and the dielectric 3 can be reduced in size in the moving direction.

That is, according to the present embodiment, the phase shift circuit 1 can be made compact while being able to increase the amount of phase shift, and can obtain good VSWR characteristics in a wide frequency band. it can.

Further, in the phase shift circuit 1, since the transformer section 7 constitutes a λ / 4 transformer corresponding to the center frequency of the signal, the design and adjustment of the transformer section 7 are easy.

Furthermore, the phase shift circuit 1 is configured so that when the dielectric 3 is moved within the moving range, it is always positioned at the signal input side and output side ends of the dielectric 3. Therefore, regardless of the position of the dielectric 3, it is possible to match the impedance between the overlapping portion 5 and the non-overlapping portion 6 and obtain good VSWR characteristics.

Next, a modified example of the present invention will be described.

A phase shift circuit 51 shown in FIG. 5A includes a low dielectric constant layer 52 made of a dielectric having a dielectric constant lower than that of the dielectric layer 7a in the air layer 7b in the phase shift circuit 1 of FIG. It is a thing. Even when the air layer 7 b is the low dielectric constant layer 52 as in the phase shift circuit 51, the transformer section 7 constitutes a λ / 4 transformer as a whole, and the like between the overlapping section 5 and the non-overlapping section 6. As long as the condition for matching the impedance of the phase shift circuit 1 is satisfied, the same effect as the phase shift circuit 1 of FIG. 1 can be obtained.

A phase shift circuit 55 shown in FIG. 5 (b) is a circuit in which the entire transformer section 7 is made of a dielectric having a lower dielectric constant than that of the dielectric 3 in the phase shift circuit 1 of FIG. Also in this case, the phase shift circuit 1 of FIG. 1 can be used as long as the conditions for matching the impedance between the overlapping portion 5 and the non-overlapping portion 6 are satisfied, such as the transformer portion 7 constituting a λ / 4 transformer as a whole. Similar effects can be obtained.

The phase shift circuit 61 shown in FIG. 6 increases the maximum area of the overlapping portion 5 where the signal conductor 2 and the dielectric 3 overlap each other by forming the signal conductor 2 in a meander shape in the phase shift circuit 1 of FIG. It is intended. That is, according to the phase shift circuit 61, the amount of phase shift can be further increased. Further, according to the phase shift circuit 61, a large amount of phase shift can be realized even if the moving distance of the dielectric 3 is reduced, so that the size of the dielectric 3 in the moving direction can be further reduced. Here, the signal conductor 2 is folded three times, and the signal conductor 2 is configured in an M shape that is rotated by 90 ° in a substantially clockwise direction as a whole. However, the number of times of folding the signal conductor 2 is not particularly limited.

7A and 7B are configured to move the dielectric 3 in a direction perpendicular to the length direction of the signal conductor 2 formed in a straight line. In the phase shift circuit 71, the dielectric 3 is formed in a triangular shape (isosceles triangular shape) having a side 72 parallel to the signal conductor 2 and two sides 73 and 74 that obliquely intersect the signal conductor 2. The transformer section 7 is formed along two sides 73 and 74 that intersect the signal conductor 2. In the phase shift circuit 71, the position of the transformer section 7 that overlaps the signal conductor 2 changes with the movement of the dielectric 3, so that at least a portion that intersects the signal conductor 2 within the movement range of the dielectric 3. It is necessary to form the transformer section 7 along the sides 73 and 74 of the current. Here, the case where the transformer section 7 is formed along the entire sides 73 and 74 is shown. The transformer section 7 is formed so that the length L along the signal conductor 2 is constant, and is formed in a parallelogram shape as a whole.

As shown in FIG. 7C, the signal conductor 2 is formed in a meander shape, and a plurality of dielectrics 3 are connected in the moving direction, that is, a plurality of phase shift circuits 71 are connected, so that a multistage phase shift is achieved. It is also possible to configure the circuit 75 and increase the amount of phase shift.

The phase shift circuit 81 shown in FIG. 8 is obtained by integrating a 1-input 2-output distribution wiring and a differential phase shift circuit. The phase shift circuit 81 includes one input signal conductor 82, two

output signal conductors

83, 84, and the derivative 3 disposed so as to overlap the

signal conductors

82, 83, 84. ing. The two

output signal conductors

83 and 84 are integrally formed in a straight line, and the input signal conductor 82 is connected to the signal conductor 83 from a direction perpendicular to the length direction of the

output signal conductors

83 and 84. , 84.

In the phase shift circuit 81, the derivative 3 has a rectangular shape having two

sides

85 and 86 along the length direction of the

output signal conductors

83 and 84 and two

sides

87 and 88 orthogonal to the two

sides

85 and 86. Is formed. In the phase shift circuit 81, the derivative 3 is moved along the length direction of the

output signal conductors

83 and 84.

In the phase shift circuit 81, the transformer section 7 is formed along a side 86 that intersects the input signal conductor 82 of the dielectric 3 and a

side

87 and 88 that intersects the

output signal conductors

83 and 84. ing. In the phase shift circuit 81, the position of the transformer section 7 that overlaps with the input signal conductor 82 changes with the movement of the dielectric 3, so that at least the input signal within the movement range of the dielectric 3. The transformer section 7 needs to be formed along the side 86 of the portion that intersects the conductor 82. Here, the case where the transformer section 7 is formed along the entire side 86 is shown.

In the phase shift circuit 81, when the dielectric 3 is moved to the left side in the figure (the output signal conductor 83 side), the phase of the signal output from the signal conductor 83 is delayed and the signal output from the signal conductor 84 is delayed. The phase will advance. Further, when the dielectric 3 is moved to the right side (the signal conductor 84 side) in the figure, the phase of the signal output from the signal conductor 83 is advanced, and the phase of the signal output from the signal conductor 84 is delayed. Thus, the phase shift circuit 81 operates as a differential phase shift circuit.

A phase shift circuit 91 shown in FIGS. 9A and 9B has a two-stage transformer section 7. The transformer section 7 formed on the signal input / output side is called a first transformer section 92, and the transformer section 7 formed on the dielectric 3 side is called a second transformer section 93. Both

transformer sections

92 and 93 constitute a λ / 4 transformer, and the length L along the signal conductor 2 is λg / 4 when the effective wavelength λg in the non-overlapping section 6 is assumed. . The characteristic impedance Z1 of the first transformer section 92 and the characteristic impedance Z2 of the second transformer section 93 are expressed by the following equations (2) and (3).
Z1 = (Zb × Z2) ^1/2 (2)
However, Zb: Characteristic impedance of the non-overlapping part 6 Z2 = (Z1 × Za) ^1/2 (3)
However, Za is set so as to satisfy both the characteristic impedances of the overlapping portion 5.

In the phase shift circuit 91, the thickness of the dielectric layer 7a of the first transformer section 92 is thinner than the thickness of the dielectric 3, and the thickness of the dielectric layer 7a of the second transformer section 93 is equal to the first transformer section. It is formed thinner than the thickness of the dielectric layer 7a of 92, and the transformer section 7 and the dielectric 3 are formed in a step shape as a whole.

The result of simulating the VSWR (voltage standing wave ratio) characteristics of the phase shift circuit 91 is shown in FIG. As shown in FIG. 10, in the phase shift circuit 91, the frequency is in the range of about 1.35 GHz to 2.4 GHz, the VSWR is 1.2 or less, the impedance matching is good, and it is good in a wider frequency band. It can be seen that a good VSWR characteristic can be realized.

Here, although the case where the transformer section 7 has a two-stage configuration has been described, a configuration having three or more stages may be used. By increasing the number of stages of the transformer section 7, a favorable VSWR characteristic can be realized in a wider frequency band.

(Summary of embodiment)
Next, the technical idea grasped from the embodiment described above will be described with reference to the reference numerals in the embodiment. However, the reference numerals and the like in the following description are not intended to limit the constituent elements in the claims to the members and the like specifically shown in the embodiments.

[1] A signal conductor (2) for transmitting a signal and a dielectric (3) disposed so as to overlap the signal conductor (2), the signal conductor (2) and the dielectric (3) Is a phase shift circuit (1) that changes the phase of the signal by changing the area of the overlapping portion (5) that overlaps with each other, and the end portions on the input side and output side of the signal of the dielectric (3) The characteristic impedance value of the non-overlapping part (6) in which the value of the characteristic impedance is larger than the value of the characteristic impedance of the overlapping part (5) and the signal conductor (2) and the dielectric (3) do not overlap. A phase shift circuit (1) with a transformer part (7) smaller than the impedance value.

[2] The phase shift circuit (1) according to [1], wherein the transformer section (7) constitutes a λ / 4 transformer corresponding to the center frequency of the signal.

[3] The phase shift circuit (1) according to [1] or [2], wherein the transformer section (7) is configured by reducing the thickness of the dielectric (3).

[4] The transformer (3) is configured to change the phase of the signal by changing the area of the overlapping portion (5) by moving the dielectric (3) within a preset moving range, When the dielectric (3) is moved within the movement range, the part (7) is configured to be always positioned at the signal input side and output side ends of the dielectric (3). The phase shift circuit (1) according to any one of [1] to [3].

[5] The phase shift circuit (1) according to any one of [1] to [4], wherein the transformer section (7) is configured in multiple stages.

[6] A ground conductor (4) disposed on the opposite side of the dielectric (3) from the signal conductor (2) and having a ground potential, the signal conductor (2) in the transformer section (7), The effective dielectric constant between the ground conductors (4) is smaller than the effective dielectric constant between the signal conductor (2) and the ground conductor (4) in the overlapping portion (5), and in the non-overlapping portion (6). The phase shift circuit (1) according to any one of [1] to [5], which is larger than an effective dielectric constant between the signal conductor (2) and the ground conductor (4).

[7] An antenna device including the phase shift circuit (1) according to any one of [1] to [6].

As mentioned above, although embodiment of this invention was described, embodiment described above does not limit the invention which concerns on a claim. In addition, it should be noted that not all the combinations of features described in the embodiments are essential to the means for solving the problems of the invention.

The present invention can be appropriately modified and implemented without departing from the spirit of the present invention.

For example, in the above-described embodiment, the case of applying to a transmission line having a triplate structure has been described. However, the structure of the transmission line is not particularly limited. For example, the present invention can be applied to a strip line.

In the above embodiment, the case where the thicknesses of the dielectric layer 7a and the dielectric 3 in the transformer section 7 are changed stepwise has been described. However, the present invention is not limited to this, and the transformer section 7 includes the dielectric layer. The thickness of 7a may be formed in a tapered shape that gradually increases toward the dielectric 3. In this case, since the characteristic impedance value gradually changes between the overlapping portion 5 and the non-overlapping portion 6, it is possible to obtain a better impedance matching state.

DESCRIPTION OF SYMBOLS 1 ... Phase shift circuit 2 ... Signal conductor 3 ... Dielectric material 4 ... Ground conductor 5 ... Overlapping part 6 ... Non-overlapping part 7 ... Transformer part 7a ... Dielectric layer 7b ... Air layer

Claims

A signal conductor for transmitting the signal;
A dielectric disposed so as to overlap the signal conductor,
A phase shift circuit that changes a phase of the signal by changing an area of an overlapping portion where the signal conductor and the dielectric overlap;
Provided at the signal input and output end portions of the dielectric, the characteristic impedance value is larger than the characteristic impedance value of the overlapping portion, and the signal conductor and the dielectric do not overlap With a transformer part smaller than the characteristic impedance value of the part,
Phase shift circuit.
The transformer section constitutes a λ / 4 transformer corresponding to the center frequency of the signal.
The phase shift circuit according to claim 1.
The transformer section is configured by reducing the thickness of the dielectric.
The phase shift circuit according to claim 1 or 2.
By moving the dielectric within a predetermined movement range, the area of the overlapping portion is changed to change the phase of the signal,
The transformer section is configured to always be positioned at the signal input side and output side ends of the dielectric when the dielectric is moved within the movement range.
The phase shift circuit of any one of Claims 1 thru | or 3.
The transformer section is configured in multiple stages,
The phase shift circuit according to claim 1.
A ground conductor disposed on the opposite side of the dielectric from the signal conductor and having a ground potential;
An effective dielectric constant between the signal conductor and the ground conductor in the transformer portion is smaller than an effective dielectric constant between the signal conductor and the ground conductor in the overlapping portion, and the signal conductor and the ground in the non-overlapping portion. Greater than the effective dielectric constant between conductors,
The phase shift circuit of any one of Claims 1 thru | or 5.
The phase shift circuit according to claim 1 is provided.
Antenna device.