JP2002171122A - Antenna device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thin type antenna device with a good gain which transmits and receives radio waves, is compact in size when installed indoors and can easily be installed. SOLUTION: An antenna device comprises a plurality of radio waves focusing and deflecting part which focus arrived radio waves 11 to increase energy density, and deflect the arrived radio waves 11; and plane antennas 18, 20 which receive the radio waves 11 focused by the radio waves focusing and deflecting part, or emit the radio waves 11 toward the radio waves focusing and deflecting part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antenna device for transmitting and / or receiving radio waves, and more particularly to transmitting and receiving radio waves in the microwave and millimeter wave ranges used for communication and broadcasting. The present invention relates to an antenna device.

[0002]

2. Description of the Related Art Heretofore, a so-called parabolic antenna has been known as a communication antenna or a broadcasting antenna in which a radio wave is focused on a focal point by a reflector such as a parabolic surface. This parabolic antenna is installed on a pillar of sufficient thickness outside, such as the roof of a building such as a building, and has sufficient strength and durability in consideration of the weight of the parabolic antenna and weather conditions such as wind and snow. It is a robust weight structure that can be obtained. However, since the parabolic antenna is installed outdoors, it is necessary to always perform maintenance to suppress aging. In addition, since the antenna is installed outside the building, the overall appearance of the building is impaired. There was also. for that reason,
Although it is conceivable to install a parabolic antenna or the like indoors, it is necessary to install a heavy structure indoors, and it is not practical because the indoor space is large.

[0003] Nowadays, due to the demand for high-speed, large-capacity communication, high-frequency communication for transmitting and receiving radio waves using microwaves and millimeter waves has been rapidly expanding. Since microwaves and millimeter waves have a wavelength of several μm to several mm, a lens or the like for focusing radio waves can be easily manufactured. Various installed antenna devices have been proposed. For example,
In JP-A-150416, a structure such as a visually transparent Fresnel lens or the like that diffracts radio waves in the microwave and millimeter wave ranges is attached instead of a window or integrally with a window or a part thereof. An antenna device has been proposed. Such a receiving portion that receives a radio wave having an increased energy density by diffracting a radio wave having a frequency in the microwave or millimeter wave band using a Fresnel lens or the like has an opening. A so-called horn antenna using a horn-type waveguide that guides waves is generally used.

[0004]

However, when such a horn antenna is used as an antenna for receiving or transmitting radio waves, a horn-type waveguide is manufactured by three-dimensionally processing a metal plate or the like. Therefore, the horn antenna and the antenna device including the horn antenna become large in size and heavy in weight, and a jig for supporting the antenna device must have high rigidity. As a result, such an antenna device is placed at a desired place in a room,
Moreover, it is difficult to install the device easily without taking up space. In addition, in order to efficiently receive a focused radio wave using a Fresnel lens or the like, the direction of the entire horn-type waveguide must be finely adjusted, and the direction cannot be easily adjusted.
Further, if the horn antenna is brought close to the Fresnel zone plate or the like in order to reduce the area occupied by the antenna device in the room, a desired radio wave transmission / reception efficiency or a desired gain cannot be obtained.

In order to solve the above problems, the present invention is directed to an antenna device that performs at least one of transmission and reception of radio waves, and is durable without being affected by deterioration due to wind and snow. It is an object of the present invention to provide a thin antenna device with good gain that can be easily installed without losing its appearance, taking up little space.

[0006]

In order to achieve the above object, the present invention provides a plurality of radio wave converging / deflecting units for converging incoming radio waves to increase energy density or deflecting incoming radio waves. And an antenna having at least one of a radio wave transmitting function of emitting a radio wave toward the radio wave focusing / deflecting unit and a radio wave receiving function of receiving the radio wave focused by the radio wave focusing / deflecting unit. An antenna device is provided.

Here, a plurality of the antennas may be arranged corresponding to each of the plurality of radio wave focusing / deflecting units,
Alternatively, one antenna may be provided for the plurality of radio wave focusing / deflecting units.

Further, when a plurality of the antennas are arranged corresponding to each of the plurality of radio wave focusing / deflecting units, it is preferable that the plurality of antennas are arranged two-dimensionally to form an array antenna. , The plurality of antennas,
Preferably, it is constituted by a microstrip antenna. Further, it is preferable that operating characteristics of the plurality of antennas when transmitting and receiving radio waves are anti-phase operating characteristics with respect to adjacent antennas. In such an array antenna, it is preferable that the transmission line to each antenna constituting the array antenna is branched from the same transmission path. For example, in the case of radio wave transmission, each antenna is branched from the same transmission line. It is preferable to use a one-point power supply system for supplying power to the power supply.

[0009] It is preferable that the radio wave focusing / deflecting unit is constituted by a Fresnel zone plate. The radio wave transmitted and received by the antenna device is preferably a microwave or a millimeter wave. Here, the microwave is 1 GHz
Up to 3 THz radio wave, millimeter wave is 30 GHz
A radio wave having a frequency of z to 300 GHz. Thus, millimeter waves constitute part of the microwave band.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an antenna device according to the present invention will be described in detail based on a preferred embodiment shown in the accompanying drawings.

An antenna device 10 shown in FIG. 1 is a preferred embodiment of the antenna device of the present invention, in which microwave and millimeter wave radio waves are diffracted using a window glass plate to increase the energy density of the radio waves. A radio wave whose energy density has been increased is received by the antenna, and a radio wave transmitted (emitted) from the antenna is deflected by using a window glass plate into a plane wave by using the reversibility of transmission and reception of the antenna device, and the predetermined wave is obtained. An antenna device that transmits radio waves in the direction. In addition,
In the present invention, the antenna does not need to have both the radio wave transmission function of transmitting radio waves and the radio wave reception function of receiving radio waves, and may have at least one of the radio wave transmission function and the radio wave reception function. The antenna device 10 includes a window glass plate 12 for diffracting and converging or deflecting the arriving radio wave 11 and two planar antennas 1.
It has a substrate circuit 22 having 8 and 20.

The window glass plate 12 is a window glass plate used for a building such as a building, and a metal thin film or a metal oxide thin film is formed on a surface on the indoor side. Needless to say, the metal thin film refers to a thin film containing a metal, but may be a thin film containing a metal oxide in addition to the metal. Also,
It goes without saying that the metal oxide thin film refers to a thin film containing a metal oxide, but may be a thin film containing a metal in addition to the metal oxide. In the regions 12a and 12b, which are part of the region where the metal thin film or metal oxide thin film is formed, the metal thin film or metal oxide thin film is concentrically removed at a predetermined width and at a predetermined interval. Is formed to form a circular orbicular zone that partially transmits light. That is, by removing the metal thin film or the metal oxide thin film in a predetermined shape along the concentric circle, the radio wave transmitting portions 14a and 16a forming a circular orb through which the radio wave is transmitted, and the radio wave reflecting the radio wave The non-transmissive portions 14b and 16b are provided alternately from the center of the concentric circle. In such regions 12a and 12b,
Radio wave transmitting portions 14a, 16a and radio wave non-transmitting portions 14b, 16
Since the interval and width of b are set to dimensions corresponding to the wavelength of microwaves or millimeter waves, the radio wave transmitting portions 14a and 16a
The radio wave 11 that has passed through is diffracted, and the radio wave 11 is focused at a position where the phases are aligned, and the energy density increases.

The areas 12a, 12a of the window glass plate 12
b uses the reversibility of transmission and reception of the antenna device, deflects the radio waves transmitted from the planar antennas 18 and 20 described later, and transmits the radio waves to a distant place as plane waves. That is,
The regions 12a and 12b form a radio wave focusing / deflecting portion in the present invention, and serve as a so-called Fresnel zone plate. Here, the Fresnel zone is a region where the phase difference of the diffracted radio waves reaching the transmitting / receiving portions of the planar antennas 18 and 20 is an integral multiple of 180 °, or the propagation path difference of the passing radio waves is an integral multiple of a half wavelength. Good ("Introduction to Optical Engineering"
Riki Ogawa, Moriaki Wakaki, Jikkyo Shuppan, pages 26-27),
The Fresnel zone plate refers to a plate provided on a radio wave propagation path so as to form this region.

In this embodiment, radio wave transmitting portions 14a and 16a and radio wave non-transmitting portions 14b and 16b are alternately provided concentrically in regions 12a and 12b of the window glass plate 12 to form a circular orbicular zone. However, in the present invention, an elliptical orbicular zone may be formed by deforming a circular orbicular zone depending on the direction in which radio waves arrive or the position where radio waves are focused. For example, in the case of an elliptical orbicular zone,
When the radio wave focusing / deflecting portion formed on the window glass plate 12 is inclined with respect to the normal direction of the surface, it is preferable to form an elliptical ring having a long axis in the inclined direction. Further, when the position where the radio wave is focused is shifted from the center position of the radio wave focusing / deflecting portion formed on the window glass plate 12, an elliptical annular zone having a long axis in the shifted direction is formed. Good.

As an example, such a window glass plate 12 is formed on an indium oxide (In ₂ O ₃ ) conductive film formed by a sputtering method as a heat-reflective conductive film.
A heat ray reflective glass plate having an undercoat and an overcoat as a protective layer is used to improve adhesion to glass. Alternatively, a metal thin film may be formed on a glass surface. Cr, T as metal thin film
A metal conductive film having a single-layer structure of a thin metal layer such as i, Ag, Au, Al, Cu, or Ni may be used. Further, an oxide semiconductor thin film such as a transparent tin oxide (SnO ₂ ) conductive film may be used instead of the metal thin film. In addition, TiO ₂ / Ag / T
A metal conductive film having a plurality of structures, such as iO ₂ , ZnO / Ag / ZnO, in which thin metal layers are stacked in a sandwich manner with transparent dielectric layers from above and below may be formed on the glass surface. The thin film such as the above-mentioned thin metal layer, metal conductive film, and oxide semiconductor thin film only needs to have radio wave reflection performance, and the lower the conductivity, the better. Such a thin film is formed by a method other than the sputtering method.
It may be performed by a spray method, a dipping method, a CVD method, or the like,
The concentric circular zone is formed by a method of decomposing and removing a predetermined portion such as a heat ray reflective glass plate, or a method of using masking or photoresist.

The radio wave focusing / deflecting portion in the present invention is not limited to the radio wave non-transmissive portion 20 of the window glass plate, which is not limited to a Fresnel zone plate formed of a metal thin film or a metal oxide thin film. A shielding film may be used. In addition, the radio wave focusing / deflecting unit of the present embodiment is obtained by patterning a metal thin film or a metal oxide thin film formed on a window glass plate into a predetermined shape. May be any radio wave focusing / deflecting unit provided on a flat substrate. For example, a separate flat Fresnel zone plate is attached to a window glass plate or the like, or
A Fresnel zone plate may be installed and fixed at a predetermined distance from the window glass plate. In addition, as a window glass plate, using a known laminated glass plate in which a plurality of glasses are bonded with a synthetic resin film or an acrylic resin interposed therebetween, on the bonding surface of the laminated glass plate, or on the laminated glass plate. A radio wave focusing / deflecting unit may be provided outside.

Such a Fresnel zone plate makes the phase difference of the arriving radio waves an integer of 180 ° by making the propagation path difference of the radio waves arriving at the transmission / reception units such as the planar antennas 18 and 20 an integral multiple of half a wavelength. Instead of the Fresnel zone plate of the above-described embodiment, the application and exposure of the photoresist are performed a plurality of times, and a concentric annular zone having the same photoresist thickness, or the same photoresist thickness is used. By forming a plurality of elliptical annular zones in a stepwise manner and changing the phase of the radio waves in a stepwise manner, the radio waves are focused to increase the energy density,
Alternatively, a phase correction type Fresnel zone plate that deflects a radio wave transmitted from an antenna may be used. Also,
The above-mentioned metal thin film or metal oxide thin film or window glass plate having no electromagnetic wave shielding film is subjected to stepwise cutting with a grindstone or the like, and a concentric annular zone having the same thickness of the window glass plate, or A stepwise shape of a plurality of elliptical orbicular zones having the same windowpane thickness is used, and the phase of radio waves changes stepwise according to the concentric or elliptical orbicular zones. The phase correction type Fresnel zone plate may be used. Further, it may be a phase correction type Fresnel zone plate in which a dipole row whose length is adjusted is formed on a window glass plate.

As shown in FIG. 1B, the board circuit 22 has, on the board, in addition to the planar antennas 18 and 20, amplification circuits 24 and 26, a power distribution / combination circuit 28, and a transmission / reception circuit 30. It is composed. The amplifying circuits 24 and 26 are parts that amplify received signals of radio waves transmitted from the planar antennas 18 and 20 or amplify input transmission signals and supply the amplified signals to the planar antennas 18 and 20, respectively.
The power distribution / combination circuit 28 is a part that combines the reception signals amplified by the amplification circuits 24 and 26 or distributes the transmission signal supplied from the transceiver 30 at a predetermined ratio. The transmission / reception circuit 30 obtains the signal information of the IF band and the baseband from the reception signal synthesized by the power distribution / combination circuit 28, outputs the signal S _out, and outputs the signal S _{out
When “in”} is supplied, this section generates a transmission signal using the carrier signal and supplies the transmission signal to the power distribution / combination circuit 28.

In the substrate circuit 22, as shown in FIG. 1C, the transmission lines from the amplifier circuit 24 'to the antennas 18 and 20 may be branched from the same transmission path. In this case, the transmission of the radio wave is a one-point power supply system in which the antenna 18 and 20 are branched from the same transmission line to supply power. On the other hand, in the case of radio wave reception, the antennas 18 and 20
Are combined by the transmission line to form one received signal. In such a system, the planar antenna 1
The line length of the feed line is adjusted so that the phases of the received signals received from 8, 20 have a desired relationship with each other.

As shown in FIG. 2, the planar antennas 18 and 20 are two microstrip antennas having a three-layer structure of patch radiators 18a and 20a, a dielectric substrate 32 and a ground substrate 34, and are array microstrips. An antenna 36 is formed. The patch radiator 18a of this array microstrip antenna 36 is
It is arranged at a predetermined distance from the window glass plate 12 so as to be installed at a position (focal position) where the radio wave 11 is focused by the Fresnel zone plate provided in the second region 12a. The patch radiator 20a is also provided on the window glass plate 12.
Is arranged at a predetermined distance from the window glass plate 12 so as to be installed at a position (focal position) where the radio wave 11 is focused by the Fresnel zone plate provided in the region 12b. Here, the microstrip antenna is an antenna having a patch radiator (strip) made of a conductive film having a rectangular, circular, or elliptical shape on a dielectric substrate with a ground substrate. Resonance occurs when the length of the antenna is half the wavelength in consideration of the effect of the dielectric of the dielectric substrate, and has directivity of transmission or reception in a direction perpendicular to the surface of the conductive film of the antenna.

Patch radiator 18a and patch radiator 20a
Have the same shape. The patch radiator 18a (20
The shape will be described with reference to FIG. 2A. As shown in FIG. 2, the protrusions 18c and 18d (20) are formed on the rectangular patch 18b (20b).
c, 20d), and the projections 18c, 18d (20c,
The feeder line 18e (20e) is drawn out from the intermediate position of 20d), and a copper foil formed in a substantially T shape is formed on the dielectric substrate 3.
It is attached to 2. The feed lines 18e and 20e are connected to amplifier circuits 24 and 26, respectively. The dielectric substrate 32 is made of a material such as ceramic or sapphire in addition to a resin material, and concentrates electric field energy on the patch radiators 18a and 20a. The ground substrate 34 is a dielectric substrate 32
Is formed of copper foil and grounded so that an electric field is generated. In the above example, the patch radiators 18a and 20a are formed of copper foil, but may be formed of a conductive film made of silver, gold, or the like.

Array microstrip antenna 36
Is manufactured by removing a copper foil on one side of a printed wiring board having copper foils on both sides so as to have a predetermined shape and processing the shape, and using the copper foil on the opposite side as a ground conductor. For example, the patch radiator 1 of the microstrip antenna 36
8a and 18b are manufactured by partially shaping and removing a copper foil used for a printed wiring board. At this time, in order to improve the physical strength of the printed wiring board, a glass fiber fabric is solidified with a resin such as an epoxy resin to form a dielectric substrate 32. In particular, it is preferable to use polytetrafluoroethylene (PTFE) or a butadiene / styrene resin in order to improve the high frequency characteristics of microwaves and millimeter waves. When the dielectric substrate 32 is a ceramic substrate, a conductive metal powder such as silver or silver-palladium, a paste material including an inorganic binder and an organic vehicle are formed on the ceramic substrate using a forming method such as screen printing, By drying and firing the formed paste material, the patch radiators 18a and 18b are made of a conductive film made of silver, silver-palladium, or the like.

Further, the array microstrip antenna 36 is a monolithic microwave integrated circuit (MMI).
C), that is, using active elements such as diodes and transistors and passive elements such as capacitors,
The transmission circuit, the modulation circuit, the amplification circuit, the detection circuit and the like may be integrally formed on one semiconductor substrate. By forming the array microstrip antenna 36 into one chip together with other circuits, a more compact configuration can be achieved.

In such an antenna device of the present embodiment,
Is an antenna device 1 shown in FIGS. 3A and 3B, for example.
At 0, b₁~ B₁₁Concentric circle group B having a diameter of₁~ B₁₁To
Radio wave transmission part R defined by₁~ R₆Consists of
The plane antenna 22 is positioned at the center of the concentric circle of the window glass plate 10.
From the focal length f in the vertical direction of the window glass plate 12._ThreeDistant
It is located at the focal position. For example, the height in FIG.
H = 0.177 m, width W = 0.208 m of 0.708 m
^TwoB on the window glass plate 12₁= 90.2mm, b_Two= 1
29.0 mm, b_Three= 159.6 mm, b_Four= 186.
2mm, b_Five= 210.3 mm, b₆= 232.6m
m, b₇= 253.7 mm, b₈= 273.8 mm, b
₉= 293.1 mm, b_Ten= 311.8 mm, b₁₁= 3
30.0 mm, radio wave transmitting part R ₁~ R₆Formed
In the case, focus on radio waves of frequency 22.605 GHz
Distance f_ThreeIs 0.15 m, and the planar antennas 18 and 20
Is placed 0.15 m away from the window glass plate 12
be able to.

On the other hand, a window glass plate 100 having the same area
Is the b shown in FIGS. 4 (a) and 4 (b).₁’-B₁₇’Diameter
Concentric circle group B₁’-B₁₇′
Excessive part R₁’-R₉′.
Is the planar antenna 102 on the surface of the window glass plate 100?
Focal length f_FourIf placed at a distant focal point,
For example, height H = 0.5 m and width W = 0.5 in FIG.
0.25m in m^TwoB on the window glass plate 100₁’=
103.9 mm, b_Two'= 148.1 mm, b _Three’= 1
82.9 mm, b_Four'= 212.8 mm, b_Five’= 23
9.8 mm, b ₆'= 264.7 mm, b₇’= 28
8.0 mm, b₈′ = 310.2 mm, b ₉’= 33
1.4 mm, b_Ten'= 351.8 mm, b₁₁’= 37
1.6 mm, b ₁₂’= 390.9 mm, b₁₃’= 40
9.6 mm, b₁₄'= 428.0 mm, b ₁₅’= 44
6.0 mm, b₁₆'= 463.6 mm, b₁₇’= 48
1.0 mm, the radio wave transmitting part R₁’-R₉’
Then, focus on the radio wave of frequency 22.605 GHz
Distance f_FourIs 0.2 m, and the planar antenna 102 is
It will be placed 0.2 m away from the lath plate 100,
Focused by the radio wave focusing / deflecting unit of the window glass plate 100 at that time.
The gain of the received radio wave is 24 dB.

Therefore, in the antenna device 10 of the present embodiment shown in FIGS. 3A and 3B, the area of the window glass plate is equal, and the area of the radio wave focusing / deflecting section is substantially equal.
Compared with the antenna device having one radio wave focusing / deflecting unit shown in (a) and (b), the installation position of the planar antenna can be closer to the window glass plate, and the antenna device can be made thinner. . Moreover, the gain of the radio waves focused by each of the two radio wave focusing / deflecting units of the window glass plate 12 is 2
Therefore, the gain of the radio wave focused by the two radio wave focusing / deflecting units is 26.5 dB.

In such an antenna device 10, the radio wave 12 arriving at the window glass plate 14 passes through the radio wave transmitting portion 18 in the area 14a, and the width and interval of the radio wave transmitting portion 18 are substantially equal to the wavelength of the radio wave. Due to the dimensions, diffraction occurs, and the energy density increases at the position where the planar antennas 18 and 20 are installed. On the other hand, in the microstrip antenna 23, an electric field is formed on the dielectric substrate 26 between the patch radiator 24 and the ground substrate 28 by a radio wave having an increased energy density, and a received signal accompanying the electric field is supplied to the feed lines 18e, 2e.
0e is electrically extracted.

On the other hand, the patch radiator 24 and the ground substrate 2 are transmitted by the transmission signals supplied from the feed lines 18e and 20e.
An electric field is formed on the dielectric substrate 26 between the points 8 and 8, and a radio wave is radiated from the patch radiator 24 in the vertical direction along with the electric field. The radiated radio wave is radiated toward the window glass plate 14, passes through the radio wave transmitting portion 18 in the area 14a, is deflected by diffraction, and becomes a plane wave traveling in a desired direction.

As described above, in the antenna device 10, the window glass plate 12 is provided with a plurality of radio wave focusing / deflecting portions having the function of a Fresnel zone plate, so that the area of the radio wave focusing / deflecting portion is reduced. The focal position where the radio wave is focused becomes shorter. Therefore, the installation position of the array microstrip antenna 36 for receiving or transmitting radio waves can also be close to the window glass plate 12, and a thin antenna device can be configured. Therefore, it can be installed easily without taking up space in the room.

The planar antennas 18 and 2 of the present embodiment
0 is an array microscopy with a patch on the plate surface.
Although the trip antenna 36 is formed, the antenna in the present invention is formed.
The antenna is not limited to this, and the dielectric
Wavelength λ considering wavelength shortening rate _gAbout a quarter of the length of
Are arranged linearly or at a certain angle.
Dipole printed with copper foil etc. on a flat surface
Antennas are arranged two-dimensionally as array antenna elements
Array antennas, directors and reflectors
It is placed before and after to enhance transmission and reception efficiency,
Yagi Uda antenna well-known as a receiving antenna for Levi broadcasting
Also, the qu which printed the deformed configuration on a flat plate surface
asi-Yagi Uda antenna as array antenna element
An array antenna arranged two-dimensionally may be used.

An antenna having such a linear element is
Microwaves and millimeter-wave radio waves have short wavelengths and require high-precision dimensional accuracy. However, they can be manufactured with high precision by linearly processing the shape from a printed wiring board. Further, a slot antenna opposed to a dipole antenna, in which a copper foil conductor of a linear element of the dipole antenna is removed to form a gap, and a conductor such as copper foil is provided around the gap, may be used. Each of these antennas can be reduced in weight and thickness and has high transmission and reception efficiency.

These array antennas are manufactured by manufacturing a printed array antenna obtained by removing a copper foil or the like by etching or the like so that a conductor such as a copper foil or the like is printed on a flat plate surface in a predetermined shape. Although it is preferable in terms of simplicity and dimensional accuracy of the present invention, the present invention is not limited to a print array antenna, and may be one in which a conductive film such as a copper foil is separately provided on the dielectric substrate 32.

In the present embodiment, the planar antennas 18 and 20 correspond to the two radio wave focusing / deflecting units formed in the regions 12a and 12b of the window glass plate 12, respectively.
8 and 20 are provided, but the radio wave focusing / deflecting portions are set so that the focal positions of the two radio wave focusing / deflecting portions are close to each other, and even if the arrangement positions of the planar antennas 18 and 20 are brought close to each other. Good. When the arrangement positions of the planar antennas 18 and 20 are close to each other, the lengths of the feed lines 18e and 20e required for combining and distributing signals from each other can be reduced, and the transmission loss of the feed lines 18e and 20e can be reduced. It is because it can suppress.

For example, in the antenna device of the present invention, FIG.
The configuration of the antenna device 10 'shown in (c) and (d) may be used. In the antenna device 10 ', the window glass plate 12'
Of the radio wave focusing / deflecting unit provided in the
It has the same configuration and arrangement except that the arrangement positions of 8 'and 20' are different. The antenna device 10 'is configured as shown in FIG.
A radio wave focusing / deflecting unit composed of elliptical rings formed by _seven ellipses S _{1 to} S ₇ on a window glass plate 12 ′ having the same shape and the same area as the window glass plate shown in FIG. Are formed symmetrically with respect to the center line of the window glass plate 12. In addition, since the focal positions of these two radio wave focusing / deflecting units are set so as to pass on the plane perpendicular to the plane of the window glass plate 12 'through the center line of the window glass plate 12', the planar antenna Reference numerals 18 'and 20' are arranged at positions separated from the center position of the sheet glass window 12 'by a predetermined distance in the vertical direction of the surface of the window crow plate 12'.

That is, the two radio wave focusing / deflecting units are provided with
It comprises a radio wave transmitting portion composed of an elliptical annular zone formed by two ellipses S _{1 to} S ₇ ,
0 'is placed in the focal position vicinity apart focal length f ₅ in the vertical direction from the center position of the concentric circles of the window glass sheet 10. For example, height H = 0.177 m and width W in FIG.
= 0.708 m on a 0.25 m ² windowpane 12 ′
An ellipse defined by the following equation (1) represented by the xy coordinate system shown in the figure is converted into parameters r _x , r
_When the radio wave transmitting portion is formed by using _y and y ₀ , the focal length f ₅ of the two radio wave focusing / deflecting portions is 0.15 for the radio wave of frequency 22.605 GHz.
m, and the focal position can be made closer to the window glass plate 12 'surface side. Therefore, the installation position of the planar antenna can be closer to the window glass plate than in the case of one radio wave focusing / deflecting unit shown in FIG. For example, the center-to-center distance between the plane antenna 18 and the plane antenna 20 shown in FIG. 3B is 0.354 m, but the center-to-center distance between the plane antenna 18 ′ and the plane antenna 20 ′ in FIG. 0.0
It can be about 1 m. Moreover, the window glass plate 1
The gain of the radio wave focused by each of the two radio wave focusing / deflecting units 2 ′ is 17.5 dB, and accordingly, the two radio wave focusing / deflecting units
The gain of the radio wave focused by the deflection unit is 23.5 dB. Furthermore, compared to the case of FIGS. 4A and 4B, since the two planar antennas 18 ′ and 20 ′ are closer,
The feed lines can be shortened by the planar antennas 18 ′ and 20 ′, and the transmission loss of the feed lines in the antenna device 10 ′ can be reduced.

X ² / r _x ² + (y−y ₀ ) ² / r _y ² = 1 (1)

[0037]

[Table 1]

FIG. 3A, FIG. 3B or FIG.
The embodiment of (d) has an array antenna in which two planar antennas are arranged, but the focal positions of two radio wave focusing / deflecting units such as the antenna device 12 'shown in FIGS. 3 (c) and 3 (d). Are substantially at the same position, FIG.
As shown in FIG. 3B, the antenna device can be configured by the same window glass plate 12 ′ as in FIGS. 3C and 3D and one planar antenna 21. This eliminates the need for the feed line 58 necessary for combining with the received signal, and can suppress transmission loss of the feed line as compared to FIGS.

As shown in FIGS. 3A to 3D,
When a planar antenna is provided corresponding to each of the two radio wave focusing / deflecting units formed in a predetermined area of the window glass plate, FIG. 2 connected to the amplifier circuits 24 and 26 shown in FIG. The lengths of the feeding lines 18e and 20e shown may be variously changed. In other words, by changing the lengths of the feed lines 18e and 20e, the mutual operation phase relationship between the array antenna elements can be variously changed, and thereby, the directivity of transmission and reception of radio waves of the array antenna can be changed. is there.

For example, if the operations of the array antenna elements are in phase with each other, the most sensitive directivity can be obtained in the front direction of the array antenna, and the operation of the adjacent array antenna elements can be 180 degrees (π radians). If the phase relation is shifted, that is, the anti-phase operation characteristic is set for the adjacent array antenna element, it is possible to obtain the directivity having the lowest sensitivity in the front direction of the array antenna and the high sensitivity in the direction deviating from the front direction. it can. The directivity can be changed by changing the operation phase relationship of the array antenna element in the case where radio waves are radiated from the planar antennas 18 and 20 shown in FIG. The radio wave radiated from the planar antenna 18 in FIG. 3A mainly passes through the radio wave focusing / deflecting unit on the left side in FIG. 3A, and the radio wave radiated from the planar antenna 20 in FIG. This is mainly because the light passes through the radio wave focusing / deflecting unit on the right side of FIG. 3A and is diffracted by the respective radio wave focusing / deflecting units. Therefore, the directivity of each array antenna can be changed by adjusting the operation phase relationship of the array antenna elements. The anti-phase operation characteristic has a phase relationship of exactly 180 degrees, but the anti-phase operation characteristic may have a phase relationship of 160 degrees or more and 200 degrees or less, and more preferably 170 degrees or more and 190 degrees or less. It is better to be in the range below degrees. In the present embodiment, one of the lengths of the transmission lines from the power distribution / combination circuit 28 to the planar antennas 18 and 20 is divided by two times the wavelength of the radio wave in consideration of the wavelength reduction ratio due to the dielectric of the dielectric substrate 32. It can be achieved by providing the length of the transmission path by lengthening or shortening by an integral multiple of the length of 1.

FIGS. 3A and 3B and FIG.
In the embodiments of (c) and (d), two radio wave focusing / deflecting units are provided, but the number of installed radio wave focusing / deflecting units is not limited, and three, four, five, etc. There may be.

FIG. 6A shows a case where the radio wave 50 is focused and
Alternatively, five radio wave focusing / deflecting units 52a to 52a to deflect are used.
2e shows an antenna device 56 having an array antenna 54 composed of array antenna elements 54a to 54e, which are planar antennas corresponding to each of them. In this case, as shown in FIGS. 3C and 3D, the focal positions of the radio wave focusing / deflecting units 52a to 52e can be close to each other or coincide with each other.
Is, as shown in FIG. 6B, the array antenna element 54
The arrangement positions of “a” to “54e” gradually approach each other, and finally one planar antenna 57 can be formed. As described above, by bringing a plurality of planar antennas close to each other or integrating them into one planar antenna, FIGS.
As in the antenna devices shown in FIGS. 3A and 3B, the feed line 58 required to combine the received signals received by the respective planar antennas into one received signal is shortened to suppress transmission loss. Can be.

In the antenna device 10, the window glass plate configured with the planar antenna is not limited to a building window glass plate installed in a building or the like, and may be a vehicle window glass plate. That is, an antenna device using a window glass of a vehicle may be used.

[Embodiment 1] FIG. 7 shows an embodiment of the present invention.
It will be described based on. As antennas, planar antennas 18 and 20 which are microstrip antennas shown in FIG.
It was used. A window glass plate 12 having a soret type (a type in which metal films are arranged concentrically) Fresnel zone plate was used as a radio wave focusing / deflecting unit. The substrates used as the planar antennas 18 and 20 as the microstrip antennas were a 50 mm square, 0.472 mm thick double-sided copper foil substrate trade name 25N (manufactured by ARLON, USA). The dimensions of the planar antennas 18, 20 are as follows. L
1 = 3.3 mm, L2 = 3.9 mm, L3 = 4.0 m
m, L4 = 0.3 mm, L5 = 1.0 mm, L6 = 1.
0 mm, L7 = 1.2 mm, L8 = 40 mm, L9 = 5
0 mm, L10 = 12 mm.

Each of the planar antennas 18 and 20 has
A reverse-phase high-frequency transmission signal having a phase shift of 180 degrees (π radians) was injected from the signal source. Planar antenna 1
Since the phases of the transmission signals sent to the antennas 8 and 20 are shifted by 180 degrees, the phases of the radio waves radiated from the planar antennas 18 and 20 are also shifted by 180 degrees. Therefore, as described above, the operation characteristics between adjacent array antenna elements become anti-phase operation characteristics, and the radio wave transmitted through the radio wave focusing / deflecting unit has low sensitivity in the front direction of the antenna and sensitivity in the direction deviated from the front direction. Will obtain high directivity. FIG.
FIG. 2 shows the result of the directivity of the antenna device. From FIG. 8, it was found that this antenna device has low sensitivity in the front direction of the antenna and high directivity with high sensitivity in the direction deviated from the front direction by 40 to 45 degrees. FIG.
The middle angle of 0 degree indicates a direction perpendicular to the plane of the planar antennas 18 and 20.

Thus, the length of the transmission line of the adjacent antenna is increased by an integral multiple of a half of the wavelength of the radio wave in consideration of the wavelength shortening ratio due to the dielectric of the dielectric substrate.
Alternatively, by shortening one of them, anti-phase operation characteristics can be provided, and the directivity having the lowest sensitivity in the front direction of the antenna and the high sensitivity in the direction deviating from the front direction can be obtained.
Further, the phase relationship between adjacent antennas can be changed by variously changing the length of the transmission line, and an antenna device having high directivity in a desired direction can be manufactured.

Then, the planar antennas 18 and 20 shown in FIG. 1 are installed in the anechoic chamber at a distance of 200 mm from the surface of the window glass plate 12 having the radio wave focusing / deflecting unit. A horn antenna is installed as a transmitting antenna at a position 1.2 m away from the installation positions of the planar antennas 18 and 20, and a signal having a frequency of 22.6 GHz and a power of 10 dBm is introduced from the signal oscillator to the horn antenna. A radio wave of 22.6 GHz was transmitted. As a result of the measurement, a gain of 10 dB was obtained.

Embodiment 2 An embodiment of the antenna device of the present invention will be described with reference to FIG. An array microstrip antenna was used as the antenna of the present invention. The array antenna was composed of two array antenna elements, and each element was composed of planar antennas 18 ″ and 20 ″, which are microstrip antennas, to provide a one-point feeding system. As the radio wave focusing / deflecting unit, a window glass plate 12 having a soret type (a type in which metal films are arranged concentrically) having a Fresnel zone plate was used. The substrate used for the array microstrip antenna is a 50 mm square, 0.472 mm thick double-sided copper foil substrate, 25N (ARLO, USA)
N company). The dimensions of the microstrip antenna were as follows. T1 = 3.3 mm, T2 =
3.9mm, T3 = 4.0mm, T4 = 0.3mm, T
5 = 1.0 mm, T6 = 1.0 mm, T7 = 1.2 m
m, T8 = 50 mm, T9 = 50 mm, T10 = 2.0
mm, T11 = 6.0 mm, T12 = 1.7 mm. Then, in the anechoic chamber, the planar antennas 18 ″, 20 ″
Is installed at a distance of 400 mm from the surface of the window glass plate 12 having the radio wave focusing / deflecting unit.
Plane antenna 18 '', 1.2m away from the plane
A horn antenna is installed as a transmitting antenna at a position opposite to the installation position of 0 '', and a frequency 2
A signal of 2.6 GHz and power of 10 dBm was introduced from a signal oscillator, and a radio wave of a frequency of 22.6 GHz was transmitted. As a result of the measurement, a gain of 10 dB was obtained.

As described above, while the transmission / reception gain of the antenna device is improved, a thin antenna device is formed, so that it is apparent that the antenna device can be installed in a room without taking up space.

Although the antenna device of the present invention has been described in detail above, the present invention is not limited to the above-described embodiment, and various improvements and modifications may be made without departing from the gist of the present invention. Of course.

[0051]

As described in detail above, the antenna device of the present invention constitutes a thin antenna device having the same performance as that of the antenna device having substantially the same area of the radio wave focusing / deflecting portion. It is possible to provide an antenna device that is less restricted and highly adaptable to a use environment.

[Brief description of the drawings]

FIG. 1A is a schematic perspective view of an embodiment of an antenna device according to the present invention, and FIG. 1B is a configuration diagram showing an example of a configuration of a substrate circuit constituting the embodiment shown in FIG. And (c) is a configuration diagram showing a configuration of another example of the substrate circuit configuring the embodiment of the present invention.

FIG. 2 is a schematic perspective view showing an example of a planar antenna included in the antenna device shown in FIG.

3A is a front view of a window glass plate of the antenna device shown in FIG. 1, FIG. 3B is a plan view of the antenna device shown in FIG. 1, viewed from above, and FIG. It is a front view of the window glass plate of the antenna device of other embodiment in the antenna device of this invention, (d) is the top view which looked at the antenna device shown to (c) from the upper part.

FIG. 4A is a front view of a window glass plate in an antenna device including one radio wave focusing / deflecting unit;
(B) is a plan view of the antenna device shown in (a).

FIG. 5A is a schematic perspective view of another embodiment of the antenna device of the present invention, and FIG. 5B is a plan view of the antenna device shown in FIG.

FIG. 6A is a schematic perspective view of another embodiment of the antenna device of the present invention, and FIG. 6B is a diagram illustrating an antenna in the antenna device shown in FIG.

FIG. 7 is a plan view showing an array microstrip antenna which is an example of an antenna in the antenna device of the present invention.

8 is a diagram showing the directivity of the array microstrip antenna shown in FIG.

FIG. 9 is a plan view showing an array microstrip antenna which is another example of the antenna in the antenna device of the present invention.

[Explanation of symbols]

10, 10 ', 100 Antenna device 11, 50 Radio wave 12, 12' Window glass plate 12a, 12b, 12a ', 12b' Region 14a, 16a Radio wave transmitting portion 14b, 16b Radio wave non-transmitting portion 18, 20, 18 ', 20 ', 18'',20'', 1
02, 21 Planar antenna 18a, 20a Patch radiator 18b, 20b Rectangular patch 18c, 18d, 20c, 20d Projection 18e, 20e Feeding line 22 Substrate circuit 24, 26, 24 'Amplifier circuit 28 Power distribution / combination circuit 30 Transmission / reception Circuit 32 Dielectric substrate 34 Ground substrate 36 Microstrip antenna 52a to 52e Radio wave focusing / deflecting unit 54 Array antenna 54a to 54e Array antenna element 56 Antenna device 57 Planar antenna 58 Feed line

 ────────────────────────────────────────────────── ─── Continued on the front page F term (reference) 5J020 AA01 BA06 BC13 CA04 DA02 5J021 AA02 AA09 AB06 BA03 GA08 HA05 JA02 5J045 AA02 AA05 DA10 EA07 FA02 HA03 NA01

Claims (3)

[Claims] 1. A plurality of radio wave converging / deflecting units for converging an incoming radio wave to increase energy density or deflecting an incoming radio wave, and radiating radio waves toward these radio wave converging / deflecting units. An antenna device comprising: an antenna having at least one of a radio wave transmitting function and a radio wave receiving function of receiving a radio wave focused by the radio wave focusing / deflecting unit. 2. The antenna device according to claim 1, wherein a plurality of said antennas are arranged corresponding to each of said plurality of radio wave focusing / deflecting units. 3. The antenna device according to claim 1, wherein one of the antennas is provided for the plurality of radio wave focusing / deflecting units.