JP2017152793A - Phase shifter and antenna device including the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a phase shifter capable of suppressing variation in the phase shift amount due to change in the distance between a signal conductor and a dielectric, and to provide an antenna device including this phase shifter.SOLUTION: A phase shifter 10 includes a first moving member 3a placed movably between a first ground plate 31 and a board 20, and a second moving member 3b placed movably between a second ground plate 32 and the board 20. The first moving member 3a has a first plate-like part 3aconsisting of a dielectric facing a signal conductor 2, and first inside protrusions 3a, 3asliding into contact with the board 20, and the interval of the first plate-like part 3aand signal conductor 2 is maintained by the first inside protrusions 3a, 3a. The second moving member 3b has a second plate-like part 3bconsisting of a dielectric facing the signal conductor 2, and second inside protrusions 3b, 3bsliding into contact with the board 20, and the interval of the second plate-like part 3band signal conductor 2 is maintained by the second inside protrusions 3b, 3b.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a phase shifter capable of changing the phase of a signal, and an antenna device including the phase shifter.

  Conventionally, a phase shifter capable of adjusting the phase of a signal transmitted or received via an antenna element is used, for example, for a base station antenna for a mobile phone (see, for example, Patent Document 1).

  The phase shifter described in Patent Document 1 is provided on a triplate line formed by sandwiching a signal conductor constituting a transmission line of a signal transmitted via an antenna element between a first ground plate and a second ground plate. A first dielectric plate disposed between the conductor and the first ground plate; and a second dielectric plate disposed between the signal conductor and the second ground plate. Both the first dielectric plate and the second dielectric plate can move forward and backward in the longitudinal direction, and the overlapping area with the signal conductor changes with the movement in the longitudinal direction. The effective dielectric constant in the triplate line changes due to the change in the overlapping area, and the electric line length changes accordingly, so that the phase of the signal propagating through the signal conductor changes.

JP 2014-158188 A

  However, the effective dielectric constant in the triplate line changes due to the forward and backward movement of the first dielectric plate and the second dielectric plate, and also due to vibration and the like, the first dielectric plate and the second dielectric with respect to the signal conductor. It also changes when the body plate is displaced in the thickness direction. In this case, the phase shift amount becomes unstable, and a desired phase shift amount cannot be obtained. Specifically, when the first dielectric plate and the second dielectric plate are moved away from the signal conductor, the phase shift amount change is reduced. That is, the amount by which the phase is delayed by the first dielectric plate and the second dielectric plate is reduced. On the other hand, when the first dielectric plate and the second dielectric plate are close to the signal conductor, the phase shift amount change becomes large. That is, the amount by which the phase is delayed by the first dielectric plate and the second dielectric plate is increased.

  Further, if the first dielectric plate and the second dielectric plate are greatly displaced in the thickness direction, and the first dielectric plate or the second dielectric plate is in direct contact with the signal conductor, the Inter Modulation (mutually) (Modulation) failure (hereinafter referred to as IM failure), the transmitted signal may affect the received signal, or the amount of phase shift may be greatly shifted. At the same time, the VSWR may be significantly deteriorated (voltage standing wave ratio is increased).

  Therefore, the present invention provides a phase shifter that can suppress fluctuations in the amount of phase shift due to a change in the distance between the signal conductor and the dielectric, and an antenna device including the phase shifter. With the goal.

  In order to achieve the above object, the present invention provides a first conductive plate and a second conductive plate that are arranged in parallel with each other on a substrate on which signal conductors constituting a transmission line of a signal transmitted through an antenna element are formed on both sides. Provided on a triplate line sandwiched between conductive plates, arranged between the first ground plate and the substrate, and parallel to the substrate in a direction in which the area facing the signal conductor changes. A movable first movable member; and a second movable member disposed between the second ground plate and the substrate and movable together with the first movable member, wherein the first movable member is at least partially Is a flat first plate-shaped portion made of a dielectric material facing the signal conductor, a first inner protrusion that is in sliding contact with the substrate, and a first outer surface that is in sliding contact with the surface of the first conductive plate facing the substrate. A protrusion, and the first inner protrusion The distance between the first plate-shaped portion and the signal conductor is maintained, and the distance between the first plate-shaped portion and the first conductive plate is maintained by the first outer protrusion, and the second moving member is At least a part of the plate-like second plate-like portion made of a dielectric material facing the signal conductor, a second inner protrusion that makes sliding contact with the substrate, and a surface of the second conductive plate facing the substrate are in sliding contact. A second outer protrusion, and a distance between the second plate-like portion and the signal conductor is maintained by the second inner protrusion, and the second plate-like portion and the second conductive member are held by the second outer protrusion. Provided are a phase shifter in which a distance from a plate is maintained, and an antenna device including the phase shifter.

  According to the phase shifter and the antenna device including the phase shifter according to the present invention, variation in the amount of phase shift due to a change in the distance between the signal conductor and the dielectric can be suppressed.

It is a block diagram which shows the antenna apparatus provided with the phase shifter which concerns on embodiment of this invention. It is explanatory drawing which shows an antenna apparatus, Comprising: (a) is a whole perspective view which shows an external appearance, (b) is a perspective view which shows the structure on the 2nd ground board which removed the radome of (a). It is a perspective view which shows an antenna apparatus and shows the structure on the 1st ground board which removed the radome. It is a perspective view which shows the board | substrate with which the wiring pattern as a signal conductor was formed. It is a figure which shows a phase shifter, (a) is the top view which abbreviate | omitted one ground plate, (b) is a top view which shows the positional relationship of the board | substrate and 1st moving member in (a). (A) is sectional drawing of the phase shifter along the AA line of Fig.5 (a). (B) is a disassembled perspective view which shows the structure of a phase shifter. It is sectional drawing which expands and shows the cross section of the phase shifter along the BB line of Fig.5 (a). It is a disassembled perspective view which shows the phase shifter which concerns on 2nd Embodiment. It is sectional drawing which shows the phase shifter which concerns on 2nd Embodiment.

[First Embodiment]
Hereinafter, a first embodiment of a phase shifter of the present invention and an antenna device including the same will be described with reference to FIGS. 1 to 7. The antenna device 11 is installed at a high place in a building such as an antenna tower or a building, and is used as a base station antenna for a mobile phone. In the following description, a case where the antenna device 11 according to the present embodiment is used for transmission of a high-frequency signal will be described, but the antenna device 11 can also be used for reception.

(Configuration of antenna device)
FIG. 1 is a block diagram showing the antenna device 11. The antenna device 11 includes an input terminal 12 to which a high-frequency signal is input, a first distribution line 14a that distributes the signal input to the input terminal 12, and a second that further distributes the signal distributed by the first distribution line 14a. The distribution line 14b, the 3rd distribution line 14c which further distributes the signal distributed by the 2nd distribution line 14b, and the antenna element 13 connected to the terminal part of the 3rd distribution line 14c are provided. Each distribution line 14a-14c has a 1-input 2-output line configuration, and a total of eight antenna elements 13a-13h are connected to the terminal portion of the third distribution line 14c, respectively.

  The eight antenna elements 13 (13a to 13h) are arranged in the vertical direction, and the antenna element 13a is disposed at the top and the antenna element 13h is disposed at the bottom. The other antenna elements 13 (13b to 13g) are arranged on the upper side in the vertical direction as the antenna element 13 shown on the upper side (antenna element 13a side) in FIG. The signal phase of each antenna element 13 is adjusted so that the signal phase of the lower antenna element 13 is delayed by the difference in line length of the first to third distribution lines 14a to 14c.

  1st thru | or 3rd distribution line 14a, 14b, 14c is the 1st distribution line 14a contained in the transmission line 1 of the signal transmitted via the antenna element 13 (13a-13h), and the 2nd distribution line 14b. The phase shifters 10 are respectively provided between the second distribution line 14b and the third distribution line 14c. Here, a total of six phase shifters 10 (in two places between the first distribution line 14a and the second distribution line 14b and four places between the second distribution line 14b and the third distribution line 14c) ( 10a to 10f). These phase shifters 10 are dielectric insertion type phase shifters in which a dielectric is inserted between a signal conductor constituting the transmission line 1 and a ground plate described later, and an area where the signal conductor and the dielectric overlap. The larger the value is, the more the signal phase is delayed.

  In the antenna device 11, the directivity (beam tilt angle) of the radio waves radiated from the antenna elements 13a to 13h can be adjusted in the vertical direction by changing the phase of the signal by the phase shifters 10a to 10f. . Specifically, the phase lag amounts of the antenna elements 13a to 13d are reduced by the phase shifters 10a, 10c, and 10d, and the phase lag amounts of the antenna elements 13e to 13h are increased by the phase shifters 10b, 10e, and 10f. The directivity of radio waves can be directed downward (ground side). Further, the phase lag amount of the antenna elements 13a to 13d is increased by the phase shifters 10a, 10c, and 10d, and the phase lag amount of the antenna elements 13e to 13h is decreased by the phase shifters 10b, 10e, and 10f. Directivity can be directed upwards (sky side). Here, the case where eight antenna elements 13 (13a to 13h) and six phase shifters 10 (10a to 10f) are used has been described, but the number of antenna elements 13 and phase shifters 10 is an example. It is not limited to the illustrated one.

  2A and 2B are perspective views showing a specific configuration example of the antenna device 11, where FIG. 2A shows an appearance and FIG. 2B shows an arrangement state of a plurality of antenna elements 13. As shown in FIG. 2A, the antenna device 11 includes a transmission line 1 including first to third distribution lines 14a, 14b, and 14c in a cylindrical radome 30, eight antenna elements 13, and the like. It is configured to accommodate. As will be described later, the transmission line 1 is constituted by a wiring pattern made of a highly conductive metal such as copper formed in a predetermined pattern on a substrate, and serves as an inner conductor of the triplate line.

  Both ends of the radome 30 are closed by antenna caps 301 and 302, and the radome 30 is attached to a high place such as an antenna tower by mounting brackets 303 and 304 so that the central axis direction is a vertical direction. Coaxial cable adapters 305 and 306 functioning as the input terminal 12 (see FIG. 1) are attached to the antenna cap 302 disposed below the vertical direction. A first ground plate 31 and a second ground plate 32 that are electrically grounded are fixed in the radome 30. In FIG. 2 (b), the second ground plate 32 is illustrated together with the eight antenna elements 13.

  The plurality of antenna elements 13 are arranged along the longitudinal direction of the radome 30 and are fixed to the second ground plate 32. Each antenna element 13 has a horizontally polarized antenna element 131 and a vertically polarized antenna element 132 arranged so as to cross each other in a cross shape. The second ground plate 32 has a function as a reflection plate that reflects electromagnetic waves radiated from the horizontal polarization antenna element 131 and the vertical polarization antenna element 132.

  The horizontally polarized antenna element 131 and the vertically polarized antenna element 132 are printed dipole antennas made of a printed circuit board in which a not-illustrated wiring pattern that functions as a radiating element is formed on a plate-like dielectric. The horizontal polarization antenna element 131 and the vertical polarization antenna element 132 are provided with an unillustrated convex portion that passes through the opening formed in the second ground plate 32, and the wiring that functions as a radiating element through the convex portion. The pattern is electrically connected to the terminal portion of the third distribution line 14c (see FIG. 1) in the transmission line 1.

  FIG. 3 is a perspective view showing a configuration example of the moving mechanism 4 of the phase shifter 10 disposed on the side opposite to the eight antenna element 13 sides inside the radome 30. The moving mechanism 4 is provided on the first ground plate 31 arranged in parallel with the second ground plate 32 to which the eight antenna elements 13 are fixed. The first ground plate 31 and the second ground plate 32 are flat conductive plates made of a conductive metal such as stainless steel or aluminum, and are electrically grounded. Further, the first ground plate 31 and the second ground plate 32 have a long plate shape whose longitudinal direction is along the central axis direction of the radome 30 and constitute an outer conductor of the triplate line. The first ground plate 31 is an aspect of the first conductive plate of the present invention, and the second ground plate 32 is an aspect of the second conductive plate of the present invention.

  The moving mechanism 4 is for moving a first moving member 3a and a second moving member 3b of the phase shifter 10 to be described later along the longitudinal direction of the first ground plate 31 and the second ground plate 32. The motor 41, a pair of drive rods 42 that move in the longitudinal direction of the first ground plate 31 and the second ground plate 32 by the driving force of the electric motor 41, and a pair of guide members 43 that guide the movement of the pair of drive rods 42. And a worm gear mechanism 44 that changes the rotational force of the electric motor 41 into a linear motion of the drive rod 42. A control unit 40 that controls the electric motor 41 in response to an external instruction signal is disposed on the second ground plate 32.

  Cutouts 31b are formed at both ends of the first ground plate 31 in the short direction, and a horizontal polarization coaxial cable 33 and a vertical polarization coaxial cable 34 are inserted through the cutout 31b. Then, the transmission signal is supplied to the first distribution line 14a (see FIG. 1) in the transmission line 1. The other ends of the horizontally polarized coaxial cable 33 and the vertically polarized coaxial cable 34 are connected to coaxial cable adapters 305 and 306.

FIG. 4 is a perspective view showing a part of the substrate 20 sandwiched between the first ground plate 31 and the second ground plate 32 and having a wiring pattern as the signal conductor 2 described later. The board | substrate 20 is comprised from the epoxy resin reinforced with the glass fiber, for example, and the wiring pattern used as the signal conductor 2 is formed in the both surfaces. The wiring patterns are provided symmetrically on both surfaces of the substrate 20 so that the same wiring pattern is formed on the back side of the wiring pattern formed on one surface of the substrate 20. Signal conductor 2, in the region P ₁ and P _2, a connecting portion 2b and the straight portion 2a to be described later, the long hole 20a of the hole portion of the present invention are formed on both sides thereof. Phase shifter 10 shown in FIG. 1 is formed in the region _{P 1} and _{P 2.}

(Configuration of phase shifter)
FIG. 5 is a diagram illustrating the phase shifter 10 according to the present embodiment illustrated in FIG. 1. FIG. 5A is a plan view illustrating the first moving member 3 a and the substrate 20 with the first ground plate 31 omitted. (B) is a top view which shows the positional relationship of the board | substrate 20 with which the signal conductor 2 in (a) was formed, and the 1st moving member 3a. FIG. 6A is a cross-sectional view of the phase shifter 10 along the line AA in FIG. FIG. 6B is an exploded perspective view showing the configuration of the phase shifter 10.

  The substrate 20 is disposed in parallel between the first ground plate 31 and the second ground plate 32 at equal intervals. The phase shifter 10 includes a first ground plate 31 and a first ground plate 31 arranged in parallel with each other on a substrate 20 on which signal conductors 2 constituting a transmission line 1 of a signal transmitted via a plurality of antenna elements 13 are formed on both sides. It is provided on a triplate line sandwiched between the two ground plates 32 with a space therebetween. Further, the phase shifter 10 includes a first moving member 3 a disposed between the first ground plate 31 and the substrate 20, and a second moving member 3 b disposed between the second ground plate 32 and the substrate 20. And.

  The signal conductor 2 constitutes a transmission line 1 for signals transmitted via the antenna elements 13 (13a to 13h). In the present embodiment, a portion of the signal conductor 2 sandwiched between the first moving member 3a and the second moving member 3b includes two linear portions 2a arranged in parallel to each other, and a tip portion of the linear portion 2a. The connection part 2b which connects each other (right edge part in FIG.5 (b)) is formed in the substantially U shape in planar view as a whole. The connecting portion between the straight line portion 2a and the connecting portion 2b has a chamfered shape.

  In the present embodiment, the signal conductor 2 is composed of a wiring pattern formed on both surfaces of the substrate 20 made of glass epoxy or the like. However, the signal conductor 2 is not limited to this, and copper or the like is used as the signal conductor 2. It may be configured using a plate-like member made of a conductor, and when a film-like substrate is used as the dielectric substrate, it is constituted by a wiring pattern formed on one surface of the film-like substrate. Also good.

  The first moving member 3a is movable in parallel with the substrate 20 in the direction in which the facing area with the signal conductor 2 (the two linear portions 2a and the connecting portion 2b) changes. The 2nd moving member 3b is connected with the 1st moving member 3a by a pair of connecting member 35 which penetrates the long hole 20a, and is movable with the 1st moving member 3a. In the present embodiment, the first moving member 3a and the second moving member 3b move along the longitudinal direction of the two straight portions 2a.

The first moving member 3 a includes a flat plate-like first plate-like portion 3 a _{1 made of} a dielectric material at least partially facing the signal conductor 2, and a pair of first inner protrusions 3 a ₂ and 3 a that are in sliding contact with the surface of the substrate 20. ₃ and a pair of first outer protrusions 3a ₄ and 3a ₅ that are in sliding contact with the surface 31a of the first ground plate 31 facing the substrate 20. Similarly, the second moving member 3 b includes a flat plate-like second plate-like portion 3 b ₁ , at least part of which is made of a dielectric material facing the signal conductor 2, and a pair of second inner protrusions 3 b that are in sliding contact with the surface of the substrate 20. ₂ and 3b ₃ and a pair of second outer protrusions 3b ₄ and 3b ₅ that are in sliding contact with a surface 32a of the second ground plate 32 facing the substrate 20.

In FIG. 5 (b), in the substrate 20, a range facing the first plate portion 3a ₁ and a region 200, a range in which the first inner protrusion _3a 2, 3a ₃ of the pair during the movement of the first moving member 3a comes into sliding contact As the areas 201 and 202, the outer edges of the areas 200 to 202 are indicated by broken lines. The region 200 partially includes the signal conductor 2, and the regions 201 and 202 do not include the signal conductor 2.

In the present embodiment, the pair of first inner protrusions 3a ₂ and 3a ₃ and the pair of first outer protrusions 3a ₄ and 3a ₅ are made of a dielectric that is integral with the first plate-like portion 3a ₁ . In addition, the pair of second inner protrusions 3b ₂ and 3b ₃ and the pair of second outer protrusions 3b ₄ and 3b ₅ are made of a dielectric integral with the second plate-like portion 3b ₁ .

The dielectric material of the first moving member 3a and the second moving member 3b is not particularly limited, but a material having a dielectric constant as large as possible is used in order to increase the change width (adjustment width) of the phase shift amount. It is desirable. Further, the amount of change in the amount of phase shift can be increased by increasing the size of the first plate-like portion 3a ₁ and the second plate-like portion 3b ₁ . Examples of a material having a large dielectric constant that can be used as the dielectric of the first moving member 3a and the second moving member 3b include LCP (liquid crystal polymer), PBT (polybutylene terephthalate), POM (polyacetal), and PPS (polyphenylene sulfide). ), PC (polycarbonate), and PPE (polyphenylene ether). However, when a material having a high dielectric constant is used as the dielectric, the amount of phase shift may be greatly fluctuated due to a slight positional deviation. As the dielectric material, a suitable material should be selected in consideration of the required change width of the phase shift amount, the size of the dielectric, and the like.

  The moving mechanism 4 moves the first moving member 3 a and the second moving member 3 b in parallel with the substrate 20. In the present embodiment, the first moving member 3a and the second moving member 3b are rectangular in a plan view as viewed from the direction perpendicular to the substrate 20, and the moving direction by the moving mechanism 4 is the longitudinal direction. Placed in.

A pair of connecting members 35 are shaped, respectively, as illustrated plates, the first plate portion 3a ₁ which is formed in the fitting hole 3c, a fitting portion 35a fitted to 3d, the second plate-shaped portion 3b ₁ is provided with fitting holes 3e and 3f formed in ₁ and fitting portions 35b to be fitted. Fitting hole 3c, 3d are formed at the two ends in the widthwise direction of the first plate-shaped portion 3a _1, fitting holes 3e, 3f are formed at both end portions of the second lateral direction of the plate-like portion 3b ₁ Has been.

  In the connecting member 35, the fitting portions 35a and 35b may be fixed to the fitting holes 3c to 3f by close fitting, or may be fixed by an adhesive. Moreover, although the shape of fitting part 35a, 35b and the fitting holes 3c-3f was made into the rectangular shape, it is not limited to this. For example, the shape may be a circle, an ellipse, a triangle, or the like.

In the first moving member 3 a, the distance between the first plate-like portion 3 a ₁ and the signal conductor 2 is maintained by the pair of first inner protrusions 3 a ₂ and 3 a ₃ . Further, the first moving member 3a is a pair of first outer protrusions _3a 4, 3a _5, the distance between the first plate-shaped portion 3a ₁ and the first ground plate 31 is maintained. Similarly, the second moving member 3b is the second inner projections _3b 2, 3b ₃ of the pair, the distance between the second plate-shaped portion 3b ₁ and the signal conductor 2 is held. In the second moving member 3b, the distance between the second plate-like portion 3b ₁ and the second ground plate 32 is maintained by the pair of second outer protrusions 3b ₄ and 3b ₅ .

Thus, the first moving member 3a and the second moving member 3b are not directly affected by the electric field formed in the immediate vicinity of the signal conductor 2, the first ground plate 31, and the second ground plate 32. The first plate-like portion 3 a ₁ and the second plate-like portion 3 b ₁ are arranged apart from the signal conductor 2 and the first ground plate 31 and the second ground plate 32. The influence of this electric field is particularly great when the first plate-like portion 3a ₁ and the second plate-like portion 3b ₁ approach the signal conductor 2, and the signal conductor 2 has the first plate-like portion 3a ₁ or the second plate-like shape. When the part 3b ₁ comes into contact, the amount of phase shift greatly fluctuates. For this reason, the first plate-like portion 3a ₁ is arranged away from the signal conductor 2 and the first ground plate 31, and the second plate-like portion 3b ₁ is separated from the signal conductor 2 and the second ground plate 32. Has been placed.

Movement of the first moving member 3a is a linear movement of the drive rod 42 (see FIG. 3) is performed by the driven projection 36 provided in the first plate portion 3a ₁ is subjected. The movement of the second moving member 3b is performed by receiving the driven protrusion 36, the first plate-shaped portion 3a ₁ , and the pair of connecting members 35 through the linear motion of the driving rod 42 (see FIG. 3). The substrate 20 has a pair of elongated holes 20a that allow the connecting member 35 to move when the first moving member 3a and the second moving member 3b move forward and backward for phase adjustment. It is formed along the moving direction of the moving member 3b. The connecting member 35 connects the first moving member 3a and the second moving member 3b through the elongated hole 20a formed in the substrate 20 so as to be integrally movable.

Hereinafter, a portion where the signal conductor 2 and the first plate-like portion 3 a ₁ and the second plate-like portion 3 b ₁ in the phase shifter 10 overlap is called an overlapping portion 5, and a portion where the signal conductor 2 does not overlap is called a non-overlapping portion 6. The non-overlapping portion 6 is a portion where the signal conductor 2 and the first and second ground plates 31 and 32 face each other with an air layer interposed therebetween.

  In the phase shifter 10, the phase of the signal transmitted through the signal conductor 2 is changed by moving the first moving member 3 a and the second moving member 3 b with the drive rod 42 and changing the area of the overlapping portion 5. In the phase shifter 10, the phase of the signal is delayed as the area of the overlapping portion 5 increases, and the phase of the signal advances as the area of the overlapping portion 5 decreases. Therefore, in FIG. 5A, by moving the first moving member 3a and the second moving member 3b from a certain reference position to the left side of the figure (the base end side of the linear portion 2a), the signal phase is changed to the phase at the reference position. The phase of the signal can be advanced from the phase at the reference position by moving the dielectric from the reference position to the right side of the figure (the tip side of the straight line portion 2a, the connection portion 2b side).

  The phase shifter 10 according to the present embodiment includes transformer parts 7A and 7B for matching impedance between the overlapping part 5 and the non-overlapping part 6. Here, the transformer portion 7A is formed at the signal input side and output side end portions (the base end side of the straight portion 2a) of the first moving member 3a and the second moving member 3b, and the straight portion 2a. Since the moving mechanism 4 is configured to move the first moving member 3a and the second moving member 3b along the longitudinal direction, the transformer section 7A has the first moving member 3a and the second moving member 3b. Even when it is moved in the left-right direction in the figure, it is always located at the signal input side and output side ends.

  In the phase shifter 10, the transformer parts 7A and 7B are provided on the high impedance part 7a provided on the overlapping part 5 side and on the non-overlapping part 6 side of the high impedance part 7a, and have a characteristic impedance higher than that of the high impedance part 7a. Is provided with a low impedance portion 7b. The effective dielectric constant between the signal conductor 2 and the first ground plate 31 and the second ground plate 32 in the high impedance portion 7a is effective between the signal conductor 2 and the first and second ground plates 31 and 32 in the low impedance portion 7b. Lower than dielectric constant.

As shown in FIG. 5A, the lengths La ₁ and La ₂ along the signal conductor 2 of the high impedance portion 7a and the lengths Lb ₁ and Lb ₂ along the signal conductor 2 of the low impedance portion 7b are The length is adjusted so that the impedance can be matched between the overlapping portion 5 and the non-overlapping portion 6.

In the phase shifter 10 illustrated in FIG. 4, the characteristic impedance of the overlapping part 5 is 21Ω, the characteristic impedance of the non-overlapping part 6 is 50Ω, and the characteristic impedance of the high impedance part 7a of the transformer parts 7A and 7B is 50Ω. The characteristic impedance of the impedance unit 7b is 21Ω. The first transformer section 7A adjusts the lengths La ₁ and Lb ₁ of the impedance sections 7a and 7b, thereby adjusting the characteristic impedance (intermediate between the non-overlapping section 6 and the overlapping section 5 and the non-overlapping section 6) (Referred to as characteristic impedance). The second transformer section 7B is configured to impedance match the intermediate characteristic impedance and the overlapping section 5 by adjusting the lengths La ₂ and Lb ₂ of the impedance sections 7a and 7b. That is, in the phase shifter 10, the transformer units 7 </ b> A and 7 </ b> B are configured to perform impedance matching between the overlapping portion 5 and the non-overlapping portion 6 in two stages.

FIG. 7 is a cross-sectional view showing an enlarged part of the cross section of the phase shifter 10 along the line BB in FIG. In the first moving member 3 a, the pair of first inner protrusions 3 a ₂ and 3 a ₃ protrude from the first plate-like portion 3 a _{1 in} the thickness direction, and the protruding amount is larger than the thickness of the signal conductor 2. For this reason, a gap S ₁ is formed between the first plate-like portion 3 a ₁ and the signal conductor 2. Similarly, in the second moving member 3b, the pair of second inner protrusions 3b ₂ and 3b ₃ protrude from the second plate-like portion 3b _{1 in} the thickness direction, and the protruding amount is larger than the thickness of the signal conductor 2. large. For this reason, a gap S ₂ is formed between the second plate-like portion 3 b ₁ and the signal conductor 2. The thickness of the signal conductor 2 is, for example, 35 μm, and the widths of the air gaps S ₁ and S ₂ in the thickness direction of the substrate 20 are, for example, 25 μm or more.

The pair of first outer protrusions 3a ₄ and 3a ₅ protrudes from the first plate-like portion 3a _{1 in} the thickness direction, and the pair of second outer protrusions 3b ₄ and 3b ₅ are the second plate-like portion 3b _1. Protrudes in the thickness direction. Thus, the first plate portion 3a ₁ and between the first ground plate 31 a gap S ₃ is formed, a second plate-shaped portion 3b ₁ is provided between the second ground plate 32 a gap S ₄ It is formed. The widths of the gaps S ₃ and S ₄ in the thickness direction of the first ground plate 31 and the second ground plate 32 are, for example, 25 μm or more. In FIG. 7, the dimensions of the air gaps S _{1 to} S ₄ and the signal conductor 2 in the thickness direction of the substrate 20 are exaggerated for clarity of explanation.

(Operation of antenna device equipped with phase shifter)
When the antenna device 11 shown in FIGS. 1 to 3 is installed in the antenna tower, the control unit 40 drives the electric motor 41 according to a required beam tilt angle. When the electric motor 41 is driven, the driving force advances or retracts the driving rod 42 via the worm gear mechanism 44. As the drive rod 42 moves forward or backward, the phase shifters 10a to 10f adjust the area of the overlapping portion 5 according to the beam tilt angle. In the present embodiment, the phase shifters 10a, 10c, and 10d and the phase shifters 10b, 10e, and 10f are arranged so that the longitudinal directions of the first moving member 3a and the second moving member 3b are opposite to each other. A phase shifter 10 is arranged. As a result, when the amount of phase shift of the phase shifters 10a, 10c, 10d increases due to the forward / backward movement of the drive rod 42, the amount of phase shift of the phase shifters 10b, 10e, 10f decreases. As described above, the antenna device 11 radiates a signal wave from the antenna element 13 at a desired beam tilt angle by moving the first moving member 3 a and the second moving member 3 b of each phase shifter 10 by the moving mechanism 4. Is possible.

(Operation and effect of the first embodiment)
According to the first embodiment described above, the following operations and effects can be obtained.

(1) first moving member 3a, the distance between the first plate portion 3a ₁ and the signal conductor 2 by a pair of first inner protrusion _3a 2, 3a ₃ is kept constant. In the second moving member 3b, the distance between the second plate-like portion 3b ₁ and the signal conductor 2 is kept constant by the pair of second inner protrusions 3b ₂ and 3b ₃ . Accordingly, suppressing the variation of the phase shift due to distance changes between the distance or the second plate-shaped portion 3b ₁ and the signal conductor 2 between the first plate portion 3a ₁ and the signal conductor 2 Can do.

(2) Since the first plate-like portion 3a ₁ or the second plate-like portion 3b ₁ can be prevented from coming into direct contact with the signal conductor 2, the occurrence of IM failure and significant deterioration of the VSWR due to the contact thereof. Can be suppressed.

(3) In the first moving member 3a, the distance between the first plate portion 3a ₁ and the first ground plate 31 by a pair of first outer protrusions _3a 4, 3a ₅ is kept constant. In the second moving member 3b, the distance between the second plate-shaped portion 3b ₁ by the second outer protrusions _3b 4, 3b ₅ of the pair and the second ground plate 32 is kept constant. Thereby, the variation in the amount of phase shift due to the change in the distance between the first plate-like portion 3a ₁ and the first ground plate 31 or the distance between the second plate-like portion 3b ₁ and the second ground plate 32. Can be suppressed.

(4) Since the pair of first inner protrusions 3a ₂ and 3a ₃ and the pair of first outer protrusions 3a ₄ and 3a ₅ are integrated with the first plate-like portion 3a ₁ , the first moving member 3a is formed by, for example, injection molding. Can be easily molded. The same applies to the second moving member 3b.

(5) Since the first moving member 3a and the second moving member 3b are connected by the pair of connecting members 35, the first moving member 3a and the second moving member 3b can be moved together.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIGS. FIG. 8 is an exploded perspective view showing the phase shifter 10 according to the second embodiment. FIG. 9 is a cross-sectional view showing the phase shifter 10 according to the second embodiment. In FIG. 8 and FIG. 9, components common to the first embodiment are denoted by the same reference numerals and redundant description is omitted.

In the first embodiment, the pair of first inner protrusions 3a ₂ and 3a ₃ and the pair of first outer protrusions 3a ₄ and 3a ₅ are made of a dielectric that is integral with the first plate-like portion 3a _1, and The case where the two inner protrusions 3b ₂ and 3b ₃ and the pair of second outer protrusions 3b ₄ and 3b ₅ are made of a dielectric integral with the second plate-like portion 3b ₁ has been described. In the second embodiment, the first moving member 3a is made of a first reinforcing member 37 of the pair of reinforcing the first plate portion 3a _1, and the first plate portion 3a _1, the second moving member 3b , The second plate-like portion 3b ₁ , and the pair of second reinforcing members 38 that reinforce the second plate-like portion 3b ₁ .

The first reinforcing member 37 includes a first inner protrusion 37a in sliding contact with the first plate-shaped portion 3a ₁ substrate 20 protrudes substrate 20 side than, than the first plate portion 3a ₁ to the first ground plate 31 side A first outer protrusion 37 b that protrudes and slidably contacts the first ground plate 31 is provided. Between the first inner protrusion 37a and the first outer protrusion 37b, the concave portion 37c of the first plate portion 3a ₁ is fitted is formed. The first reinforcing member 37 of the pair is rigid than the first plate portion 3a ₁ is made of a material having high, for example, it is fixed to the first plate-shaped portion 3a ₁ by adhesion, and reinforces the first plate-shaped portion 3a ₁ Yes. Further, the pair of first reinforcing members 37 sandwich the first plate-like portion 3a ₁ having a rectangular shape in a short view in a plan view.

Similarly, second reinforcing member 38 includes a second inner protrusions 38a in sliding contact with the substrate 20 to protrude on the second substrate 20 side of the plate-shaped portion 3b _1, the second ground plate than the second plate-shaped portion 3b ₁ And a second outer protrusion 38 b that protrudes toward the side 32 and is in sliding contact with the second ground plate 32. Between the second inner protrusion 38a and the second outer protrusion 38b, a recess 38c into which the second plate-like portion 3b ₁ is fitted is formed. A pair of second reinforcing member 38 is made of the second plate-shaped portion material stiffer than 3b _1, for example, it is fixed to the second plate-shaped portion 3b ₁ by bonding, to reinforce the second plate-shaped portion 3b ₁ Yes. The second reinforcing members 38 of the pair is sandwiching the second plate-shaped portion 3b ₁ rectangular in transverse direction in a plan view.

The material of the first reinforcing member 37 and the second reinforcing member 38 may be a resin that is harder than the first plate-like portion 3a ₁ and the second plate-like portion 3b ₁ , for example, a material other than a resin such as ceramic. It may be. However, it is desirable that the first reinforcing member 37 and the second reinforcing member 38 have electrical insulation.

Also according to the second embodiment, the operations and effects (1), (2) and (4) described in the first embodiment can be obtained. Further, the pair of first reinforcing members 37 suppresses the distortion of the first plate-like portion 3a ₁ , and the pair of second reinforcing members 38 suppresses the distortion of the second plate-like portion 3b ₁ . Thus, it is possible to suppress the variation in the amount of phase shift by the first plate-shaped portion 3a ₁ or the second strain of the plate-like portion 3b _1.

(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, each reference numeral in the following description does not limit the constituent elements in the claims to members or the like specifically shown in the embodiment.

[1] A first conductive plate in which signal substrates (2) constituting a transmission line (1) for signals transmitted via an antenna element (13) are formed on both sides of a substrate (20) arranged in parallel with each other. The first conductive plate (31) and the substrate (20) are provided on a triplate line sandwiched between the (first ground plate 31) and the second conductive plate (second ground plate 32). Between the first moving member (3a) and the second conductive plate (32) that are movable in parallel with the substrate (20) in a direction in which the area facing the signal conductor (2) changes. ) And the substrate (20), and a second moving member (3b) movable together with the first moving member (3a), the first moving member (3a) being at least partially Is a flat plate-like first plate portion (3) made of a dielectric material facing the signal conductor (2). _1), the has a sliding contact with the first inner projection on the substrate _{(20) (3a 2, 3a} 3), wherein the first plate-shaped portion by a first inner protrusion _{(3a 2, 3a 3) (} 3a 1 ) And the signal conductor (2), and the second moving member (3b) is a flat plate-like second plate-shaped portion made of a dielectric material at least partially facing the signal conductor (2). (3b ₁ ) and second inner protrusions (3b ₂ , 3b ₃ ) that are in sliding contact with the substrate (20), and the second plate-like portion (3b ₂ , 3b ₃ ) 3b ₁ ) and the signal conductor (2), the phase shifter (10) is maintained.

[2] the first moving member (3a), the sliding contact first outer projection on the first conductive plate _{(31) (3a 4, 3a} 5) further comprising a first outer protrusion _(3a 4, 3a ₅ ), the distance between the first plate-like portion (3a ₁ ) and the first conductive plate (31) is maintained, and the second moving member (3b) is in slidable contact with the second conductive plate (32). 2 outer protrusions (3b ₄ , 3b ₅ ), and the second outer protrusions (3b ₄ , 3b ₅ ) allow a distance between the second plate-like portion (3b ₁ ) and the second conductive plate (32). The phase shifter (10) according to [1], which is held.

[3] In the first moving member (3a), the first inner protrusions (3a ₂ , 3a ₃ ) and the first outer protrusions (3a ₄ , 3a ₅ ) are the same as the first plate-shaped part (3a ₁ ). The second moving member (3b) is composed of an integral dielectric, and the second inner protrusions (3b ₂ , 3b ₃ ) and the second outer protrusions (3b ₄ , 3b ₅ ) are formed on the second plate-shaped portion ( 3b ₁ ) and the phase shifter (10) according to the above [2], which is made of a dielectric integral with the body.

[4] The first moving member (3a) includes the first plate-like portion (3a ₁ ) and the first reinforcing member (37) that reinforces the first plate-like portion (3a ₁ ). The first reinforcing member (37) is provided with the first inner protrusion (37a) and the first outer protrusion (37b), and the second moving member (3b) includes the second plate-like portion (3b ₁ ), and The second reinforcing member (38) reinforces the second plate-like portion (3b ₁ ), and the second inner protrusion (38a) and the second outer protrusion (38b) are formed on the second reinforcing member (38). The phase shifter (10) according to [2], provided.

[5] A connecting member that connects the first moving member (3a) and the second moving member (3b) so as to be integrally movable through a hole (long hole 20a) provided in the substrate (20). 35) The phase shifter (10) according to any one of [1] to [4], further comprising:

[6] An antenna device (11) including the phase shifter (10) according to any one of [1] to [5].

  While the embodiments of the present invention have been described above, the embodiments described above do not limit the invention according to the claims. 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.

Further, the present invention can be appropriately modified and implemented without departing from the spirit of the present invention. For example, in the first embodiment, the first moving member 3a and the second moving member 3b have a rectangular shape in plan view, and a pair of first portions along the long side direction at both ends in the short side direction. The case where the inner protrusions 3a ₂ and 3a ₃ and the second inner protrusions 3b ₂ and 3b ₃ and the pair of first outer protrusions 3a ₃ and 3a ₄ and the second outer protrusions 3b ₄ and 3b ₅ are provided has been described. However, the first inner protrusion, the second inner protrusion, the first outer protrusion, and the second outer protrusion may be, for example, boss-shaped (columnar) protrusions. Further, the number and position of these protrusions are not limited to those exemplified in the above embodiment.

DESCRIPTION OF SYMBOLS 1 ... Transmission line 10 ... Phase shifter 11 ... Antenna apparatus 2 ... Signal conductor 20 ... Board | substrate 31 ... 1st ground board (1st conductive board)
32. Second ground plate (second conductive plate)
35 ... connecting member 37 ... first reinforcing member 37a ... first inner protrusion 37b ... first outer protrusions 38 ... second reinforcing member 38a ... second inner protrusions 38b ... second outer protrusions 3a ... first moving member 3a 1 _... first 1 plate portion _3a 2, 3a 3 _... first inner protrusion _3a 4, _3a 5 _... first outer protrusion 3b ... second moving member 3b 1 _... second plate-shaped portion _3b 2, 3b 3 _... second inner projections 3b ₄ , 3b ₅ ... second outer protrusion

Claims (6)

A triplate comprising a substrate on which both sides of a signal conductor constituting a transmission line for a signal transmitted via an antenna element are formed with a space between a first conductive plate and a second conductive plate arranged in parallel to each other Provided on the track,
A first moving member that is disposed between the first conductive plate and the substrate and is movable in parallel with the substrate in a direction in which an opposing area of the signal conductor changes;
A second moving member disposed between the second conductive plate and the substrate and movable together with the first moving member;
The first moving member has a flat plate-shaped first plate-shaped portion at least partially made of a dielectric material facing the signal conductor, and a first inner protrusion that is in sliding contact with the substrate. The distance between the first plate-like portion and the signal conductor is maintained by
The second moving member has a flat plate-like second plate-shaped portion at least partially made of a dielectric material facing the signal conductor, and a second inner protrusion that is in sliding contact with the substrate. The distance between the second plate-like portion and the signal conductor is maintained by
Phase shifter. The first moving member further includes a first outer protrusion that is in sliding contact with the first conductive plate, and the first outer protrusion maintains a distance between the first plate-like portion and the first conductive plate,
The second moving member further includes a second outer protrusion that is in sliding contact with the second conductive plate, and a distance between the second plate-like portion and the second conductive plate is maintained by the second outer protrusion.
The phase shifter according to claim 1. The first moving member is made of a dielectric in which the first inner protrusion and the first outer protrusion are integrated with the first plate-shaped portion,
The second moving member is made of a dielectric in which the second inner protrusion and the second outer protrusion are integrated with the second plate-like portion.
The phase shifter according to claim 2. The first moving member includes a first reinforcing member that reinforces the first plate-like portion and the first plate-like portion, and the first reinforcing member is provided with the first inner protrusion and the first outer protrusion. And
The second moving member includes a second reinforcing member that reinforces the second plate-like portion and the second plate-like portion, and the second inner protrusion and the second outer protrusion are provided on the second reinforcing member. Was,
The phase shifter according to claim 2. A connecting member that connects the first moving member and the second moving member so as to be integrally movable through a hole provided in the substrate;
The phase shifter of any one of Claims 1 thru | or 4. The phase shifter according to any one of claims 1 to 5 is provided.
Antenna device.

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