JP2012085145A - Antenna device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To change the frequency characteristics to desired characteristics in an antenna device which feeds a high frequency signal to a radiation element via a slot.SOLUTION: The antenna device comprises a first dielectric layer 11 containing a variable dielectric constant material having a dielectric constant dependent on an electric field to be applied, a radiation element 2 provided on the first surface of the first dielectric layer 11, a ground conductor 4 provided on the second surface of the first dielectric layer 11 and having a slot formed at a position facing the radiation element 2, and a first electrode pattern 51 provided on the first surface of the first dielectric layer 11 so as not to overlap the radiation element 2 in the vertical direction and to which a variable voltage can be applied. In the antenna device, electric length of the radiation element 2 is changed by applying a predetermined electric field from the first electrode pattern 51 to the first dielectric layer 11 thereby changing the dielectric constant of the first dielectric layer 11.

Description

  The present invention relates to an antenna device, and more particularly to an antenna device capable of changing frequency characteristics.

  For millimeter-wave short-range radar, a standard has been established in which a bandwidth of about 4 GHz is frequency-divided into four channels. In order to cope with a plurality of channels that are frequency-divided by one resonance-type narrow band antenna typified by a patch antenna, it is necessary to change the frequency characteristics. The following technologies exist for antenna devices that can change frequency characteristics.

  Patent Document 1 discloses a technique related to a patch antenna device that can cover a wide frequency band or a plurality of frequencies with one antenna. FIG. 12 is a diagram showing a patch antenna device disclosed in Patent Document 1. As shown in FIG. As shown in FIG. 12, the patch antenna device disclosed in Patent Document 1 includes a glass substrate 104 provided with a patch portion 102 on the back surface, a ground substrate 103 set at an earth potential, and the back surface and ground of the glass substrate 104. A patch antenna including a liquid crystal layer 101 interposed between the substrate 103 and a variable electric field applying unit 105 for applying a variable electric field between the patch unit 102 and the ground substrate 103 is provided. Then, by changing the dielectric constant of the liquid crystal layer 101 by changing the magnitude and direction of the electric field applied to the liquid crystal layer 101 using the variable electric field applying means 105, a patch antenna that can cope with a plurality of frequencies is configured. ing.

  FIG. 13 is a diagram showing an antenna device disclosed in Patent Document 2. In FIG. As shown in FIG. 13, the antenna device disclosed in Patent Document 2 is provided with a radiating element 220 and a conductive line 220 ′ on an insulating layer 230. The insulating layer 230 is provided on the LCD including the transparent electrode 225, the upper dielectric plate 230 ′, the liquid crystal 250, the lower dielectric plate 255, and the lower electrode 260. The lower electrode 260 is connected to a common potential, for example, a ground potential. Transparent electrodes 225 can be individually coupled to potential 290. When the potential on any of the transparent electrodes 225 changes, the dielectric constant of the liquid crystal below the electrodes changes, and as a result, a phase change of the conductive line 220 ′ is induced. The phase change can be controlled by controlling the amount of voltage applied to the transparent electrode 225 and by controlling the number of electrodes to which the voltage is applied.

  Patent Document 3 discloses a technique related to a stripline transmission line that can change transmission characteristics by changing the dielectric constant of a substrate. Patent Document 4 discloses a technique related to a ferroelectric antenna and its adjustment method. Patent Document 5 discloses a technique related to an antenna device capable of widening the bandwidth by changing the antenna resonance frequency.

JP 2000-341027 A Special table 2009-538565 gazette International Publication No. 2008/007545 JP 2008-167474 A Japanese Patent Laid-Open No. 11-154821

  FIG. 14 is a diagram illustrating an example of a patch antenna device. The patch antenna device shown in FIG. 14 includes dielectric layers 309 and 313, a radiating element (patch portion) 302, a slot 303, a ground conductor 304, and a line conductor 307. In the patch antenna apparatus shown in FIG. 14, a high-frequency signal supplied from the RF transmitter 308 is fed to the radiating element 302 via the slot 303.

  On the other hand, in the patch antenna device according to Patent Document 1, a bias (DC voltage) is supplied to the patch portion 102 provided on the back surface of the glass substrate 104, and the dielectric constant of the liquid crystal layer 101 using an electric field applied by the bias. Is changing. As described above, by changing the dielectric constant of the liquid crystal layer 101, the patch antenna can correspond to a plurality of frequencies.

  However, since the patch antenna having the configuration shown in FIG. 14 feeds a high-frequency signal to the radiating element 302 via the slot 303, it is not possible to supply a bias (DC voltage) to the radiating element 302. For this reason, the configuration disclosed in Patent Document 1 shown in FIG. 12 is applied to a patch antenna having the configuration shown in FIG. 14, that is, a patch antenna that feeds a high-frequency signal to the radiating element via a slot. I can't.

  In the antenna device disclosed in Patent Document 2 shown in FIG. 13, a transparent electrode 225 is provided on the upper dielectric plate 230 ′. For this reason, the configuration disclosed in Patent Document 2 cannot be applied to the patch antenna shown in FIG. 14 that feeds a high-frequency signal to the radiating element 302 via the slot 303.

  In view of the above problems, an object of the present invention is to change a frequency characteristic to a desired characteristic in an antenna device that feeds a high-frequency signal to a radiating element through a slot.

  An antenna device according to the present invention includes a first dielectric layer including a variable dielectric constant material whose dielectric constant changes depending on an applied electric field, and a radiation element provided on a first surface of the first dielectric layer. And a ground conductor provided on the second surface of the first dielectric layer and having a slot formed at a position facing the radiating element, and the first surface side of the first dielectric layer And a first electrode pattern that can be applied with a variable voltage, so that a predetermined electric field is applied from the first electrode pattern to the first dielectric layer. When applied, the dielectric constant of the first dielectric layer is changed to change the electrical length of the radiating element.

  According to the present invention, in an antenna device that feeds a high-frequency signal to a radiating element through a slot, the frequency characteristic can be changed to a desired characteristic.

1 is a perspective view showing an antenna apparatus according to a first embodiment. 1 is a top view showing an antenna device according to a first embodiment; It is sectional drawing in AA of the antenna apparatus shown in FIG. FIG. 7 is a cross-sectional view showing another aspect of the antenna device according to the first embodiment. FIG. 7 is a cross-sectional view showing another aspect of the antenna device according to the first embodiment. FIG. 6 is a diagram showing another aspect of the antenna device according to the first exemplary embodiment. (A) is a perspective view which shows an antenna device, (b) is sectional drawing in BB of the antenna device shown to (a). FIG. 3 is a diagram illustrating an antenna device according to a second embodiment. (A) is a perspective view which shows an antenna device, (b) is sectional drawing in CC of the antenna device shown to (a). It is a figure which shows the other aspect of the antenna apparatus concerning Embodiment 2. FIG. (A) is a perspective view which shows an antenna device, (b) is sectional drawing in DD of the antenna device shown to (a). It is a figure which shows the result of the electrostatic field simulation of the antenna apparatus concerning Embodiment 2. FIG. It is a figure which shows the array antenna apparatus concerning Embodiment 3. FIG. It is a figure which shows the other aspect of the array antenna apparatus concerning Embodiment 3. FIG. It is a figure for demonstrating background art. It is a figure for demonstrating background art. It is a figure for demonstrating the subject of this invention.

Embodiment 1
Embodiment 1 of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing an antenna device according to the present embodiment. FIG. 2 is a top view showing the antenna device according to the present embodiment. 3 is a cross-sectional view taken along line AA of the antenna device shown in FIG.

  As shown in FIGS. 1 to 3, the antenna device according to the present embodiment includes a first dielectric layer 11 including a variable dielectric constant material whose dielectric constant changes depending on an applied electric field, and a first dielectric layer. 11 is formed on the lower surface (second surface) of the first dielectric layer 11 and the slot 3 is formed at a position facing the radiating element 2. And a first electrode pattern 51 that is provided on the upper surface side of the first dielectric layer 11 so as not to overlap the radiating element 2 in the vertical direction and to which a variable voltage can be applied. In the antenna apparatus according to the present embodiment, a predetermined electric field is applied from the first electrode pattern 51 to the first dielectric layer 11 to change the dielectric constant of the first dielectric layer 11, thereby radiating element 2. The electrical length is changed. Thereby, in the antenna device that feeds a high-frequency signal to the radiating element 2 via the slot 3, the frequency characteristic can be changed to a desired characteristic. Hereinafter, the antenna device according to the present embodiment will be described in detail.

  The first dielectric layer 11 is a dielectric layer including a variable dielectric constant material whose dielectric constant changes according to an applied electric field. Here, as the variable dielectric constant material, for example, a dielectric ceramic material such as barium titanate having an electric field dependence characteristic of a relative dielectric constant or a liquid crystal material can be used. As shown in FIG. 3, the patch-shaped radiation element 2 is provided on the upper surface of the first dielectric layer 11. A ground conductor 4 is provided on the lower surface of the first dielectric layer 11.

  As shown in FIG. 2, the radiating element 2 may be, for example, a square. However, the shape of the radiating element 2 is not limited to this, and may be any other shape. A slot 3 is formed in the ground conductor 4 at a position facing the radiating element 2. The shape of the slot 3 can be a cross shape, for example. However, the shape of the radiating element 2 is not limited to this, and may be any other shape. That is, the shape of the radiating element 2 and the slot 3 is not limited to the shape shown in FIG. 2, and may be any shape as long as it can radiate and transmit a high-frequency signal. The ground conductor 4 is connected to the ground potential 41.

  A second dielectric layer 12 may be further formed on the top surfaces of the first dielectric layer 11 and the radiating element 2. A normal dielectric material may be used for the second dielectric layer 12, and a variable dielectric constant material may be used similarly to the first dielectric layer 11. A first electrode pattern 51 is formed on the upper surface of the second dielectric layer 12. The shape of the first electrode pattern 51 is preferably a shape that does not overlap with the radiating element 2 in the vertical direction. That is, as shown in FIG. 2, when the antenna device according to the present embodiment is viewed from above, it is preferable that the radiating element 2 and the first electrode pattern 51 do not overlap each other.

  In the present embodiment, as shown in FIG. 2, the shape of the first electrode pattern 51 can be a shape having a square opening corresponding to the radiating element 2. The shape of the first electrode pattern 51 is not limited to the shape shown in FIG. Further, as described above, it is preferable that the first electrode pattern 51 does not cover the radiating element 2 so as not to disturb the radiated signal. However, when the influence on the radiated signal is small, the first electrode pattern 51 The shape of the pattern 51 may be a shape that slightly overlaps the radiation element 2 in the vertical direction.

  The first electrode pattern 51 is connected to a first DC power source (variable voltage DC power source) 61. The first DC power supply 61 can apply a DC voltage (variable) to the first electrode pattern 51. Here, the polarity of the first DC power supply 61 may be positive or negative. The first electrode pattern 51 is preferably grounded via a capacitor so as to be grounded for a high-frequency signal.

  Further, a third dielectric layer 13 may be provided on the lower surface of the first dielectric layer 11. In this case, the line conductor 7 is provided on the surface (lower surface) opposite to the first dielectric layer 11 of the third dielectric layer 13, and a high frequency signal is supplied to the line conductor 7 from the RF transmitter 8. The high frequency signal can be supplied to the slot 3.

  In the antenna device according to the present embodiment having the above-described configuration, a voltage is applied from the first DC power supply 61 to the first electrode pattern 51, so that the first electrode pattern 51 and the ground conductor 4 are interposed between each other. A predetermined electric field is applied. Here, the first dielectric layer 11 made of the radiating element 2 and the variable permittivity material exists between the first electrode pattern 51 and the ground conductor 4 (see FIG. 3). Therefore, the dielectric constant of the variable dielectric constant material immediately below the radiating element 2 changes due to the generated electric field. When the dielectric constant immediately below the radiating element 2 changes, the electrical length of the radiating element 2 changes, and the resonance frequency of the antenna device changes. Therefore, it is possible to change the frequency characteristic of the antenna device having a configuration in which a high-frequency signal is fed to the radiating element 2 through the slot 3.

  The configuration of the antenna device according to the present embodiment can be appropriately changed as follows. In the antenna device shown in FIGS. 1 to 3, the second dielectric layer 12 is formed on the upper surfaces of the first dielectric layer 11 and the radiating element 2, and the first dielectric layer 12 is formed on the upper surface of the second dielectric layer 12. The example which formed the electrode pattern 51 was shown. However, the arrangement and shape of the first electrode pattern 51 does not hinder the feeding of the high-frequency signal from the lower part, and an electric field is generated around the radiating element 2 so that the dielectric constant of the first dielectric layer 11 can be changed. If it is a structure, it is good also as a structure shown in FIG. That is, the first electrode pattern 51 may be formed on the upper surface of the first dielectric layer 11 (that is, on the same plane as the radiating element 2) without providing the second dielectric layer 12. At this time, if the first electrode pattern 51 connected to the first DC power supply 61 and the radiating element 2 are electrically connected, the radiation characteristics of the antenna are greatly affected. It is preferable that 51 and the radiating element 2 are not electrically connected.

  Further, since air is also a dielectric, as shown in FIG. 5, the second dielectric layer 12 is made of air, that is, the first electrode pattern 51 is separated from the radiating element 2 in the direction perpendicular to the radiating element 2. It is good also as a structure formed in the upper part. At this time, another support is required to fix the first electrode pattern 51. However, if the rigidity of the first electrode pattern 51 is high, it is not necessary to dispose the support near the radiating element 2.

  In the antenna apparatus shown in FIGS. 1 to 3, the line conductor 7 and the third dielectric layer 13 connected to the RF transmitter 8 are provided to feed a high-frequency signal to the slot 3. However, the method for supplying power to the slot 3 is not limited to this, and a slot line 31 is provided in the ground conductor 4 as shown in FIGS. 6A and 6B, and power is supplied using the slot line 31. May be. In addition to connecting to the RF transmitter 8, for example, it may be connected to a receiver, an amplifier, a coupler, or the like. 6A and 6B, the second dielectric layer 12 is provided on the upper surface of the first dielectric layer 11, and the first electrode pattern 51 is provided on the upper surface of the second dielectric layer 12. An example was provided. However, also in the antenna device shown in FIGS. 6A and 6B, the configuration in which the second dielectric layer 12 is air as shown in FIG. 5, that is, the first electrode pattern 51 is used as the radiating element 2. It is good also as a structure formed in the upper part of the radiation | emission element 2 spaced apart in the perpendicular direction.

  Next, an example of a method for manufacturing the antenna device according to the present embodiment will be described. For example, when a variable dielectric constant material such as liquid crystal that cannot keep its shape alone is used as the first dielectric layer 11, it is configured as follows. A rigid dielectric substrate (corresponding to the third dielectric layer 13) on which the ground conductor 4 provided with the slot 3 is formed, and a rigid dielectric substrate (second dielectric layer) on which the radiation element 2 and the electrode pattern 51 are formed. 12), the variable dielectric constant material is sandwiched. The periphery of these rigid dielectric substrates is covered with a rigid dielectric.

  When a variable dielectric constant material such as a highly rigid ferroelectric is used, a ground conductor 4 having a slot 3 provided on the back surface of a substrate 11 (corresponding to the first dielectric layer 11) made of a variable dielectric constant material is provided. It can be manufactured by forming and forming the radiation element 2 and the electrode pattern 51 on the surface of the substrate 11. Alternatively, the dielectric substrate 12 having the electrode pattern 51 formed on the variable dielectric constant substrate 11 (corresponding to the first dielectric layer 11) on which the radiating element 2 to be fed using the slot 3 is formed (the second substrate). It can also be manufactured by laminating (corresponding to the dielectric layer 12). Further, the entire substrate 11 may be covered with the electrode pattern 51.

  The 1st electrode pattern 51 can be made into the same shape as the metal case used for antenna protection. At this time, the structure of the antenna device according to the present embodiment includes a first metal case covering a variable dielectric constant substrate 11 (corresponding to the first dielectric layer 11) on which the radiating element 2 and the ground conductor 4 are formed. A DC power supply 61 is connected. The air layer between the variable dielectric constant substrate 11 and the metal case corresponds to the second dielectric layer 12.

  As with the first electrode pattern 51, a metal case having an opening directly above the radiating element is used as the metal case used for antenna protection in order not to inhibit radiation. For protective applications, connect the metal case to ground potential. However, in the antenna device according to the present embodiment, a variable dielectric constant substrate 11 (first electrode) on which the radiating element 2 and the ground conductor 4 are formed by applying a variable potential to the metal case using the first DC power supply 61. 1 corresponding to the dielectric layer 11) can be changed.

  As described above, in the antenna device according to the present embodiment, by applying a voltage from the first DC power supply 61 to the first electrode pattern 51, the first electrode pattern 51 and the ground conductor 4 can be connected. A predetermined electric field is applied between them. Therefore, the dielectric constant of the variable dielectric constant material immediately below the radiating element 2 changes due to the generated electric field. When the dielectric constant immediately below the radiating element 2 changes, the electrical length of the radiating element 2 changes, and the resonance frequency of the antenna device changes. Therefore, it is possible to change the frequency characteristic of the antenna device having a configuration in which a high-frequency signal is fed to the radiating element 2 through the slot 3.

  In addition, according to the invention according to the present embodiment, it is possible to provide an antenna device that can handle a plurality of channels with one antenna device in a frequency band having frequency-divided channels. That is, since it is not necessary to prepare an antenna device for each channel, the cost and size of the entire antenna device can be reduced. Further, since it is a resonance type narrow band antenna device, it is difficult to be influenced by signals in other frequency bands including adjacent channels. For this reason, the signal of a desired channel can be acquired efficiently.

Embodiment 2
Next, a second embodiment of the present invention will be described. Fig.7 (a) is a perspective view which shows the antenna apparatus concerning this Embodiment. FIG.7 (b) is sectional drawing in CC of the antenna device shown to Fig.7 (a). Compared with the antenna device according to the first embodiment, the antenna device according to the present embodiment has a configuration for changing the electrical length of the slot 3, the fourth dielectric layer 14, the second electrode pattern 52. , And a second DC power source 62. Other than this, it is the same as that of the antenna device according to the first embodiment. Therefore, the same components are denoted by the same reference numerals, and redundant description is omitted.

  That is, like the radiating element 2, the slot 3 used for feeding a high-frequency signal also has a frequency characteristic depending on its electrical length. Further, it is difficult to change the frequency characteristic of the slot 3 together with the frequency characteristic of the radiating element 2 with only the first DC power supply 61. For this reason, in order to change the frequency characteristics of the slot 3, it is preferable to change the dielectric constant in the slot 3 independently. By changing the frequency characteristics of the slot 3 together with the frequency characteristics of the radiating element 2, good RF transmission characteristics can be obtained at various frequencies.

  The antenna device according to the present embodiment shown in FIGS. 7A and 7B is connected to the ground in addition to the components of the antenna device according to FIGS. 6A and 6B described in the first embodiment. A fourth dielectric layer 14 including a variable dielectric constant material provided on the lower surface of the conductor 4 and the first dielectric layer 11 (that is, the lower surface side of the first dielectric layer 11), and a fourth dielectric A second electrode pattern 52 provided on the surface of the layer 14 opposite to the first dielectric layer 11 and capable of applying a variable voltage. A second DC power source (variable voltage DC power source) 62 capable of applying a variable voltage is connected to the second electrode pattern 52. For the fourth dielectric layer 14, for example, a dielectric ceramic material such as barium titanate having electric field dependence characteristics of a relative dielectric constant can be used. Here, in the antenna device shown in FIGS. 7A and 7B, power can be supplied using the slot line 31 provided in the ground conductor 4.

  In the antenna device according to the present embodiment shown in FIGS. 7A and 7B, an electric field is generated in the vicinity of the slot 3 by applying a predetermined electric field from the second electrode pattern 52. Here, the first dielectric layer 11 and the fourth dielectric layer 14 made of a variable dielectric constant material exist in the vicinity of the slot 3. Therefore, the dielectric constant of the dielectric in the slot 3 changes due to the electric field generated in the vicinity of the slot 3. When the dielectric constant in the slot 3 changes, the electrical length of the slot 3 changes, so the frequency characteristic of the slot 3 changes.

  Moreover, Fig.8 (a), (b) is a figure which shows the other aspect of the antenna apparatus concerning this Embodiment. FIG. 8A is a perspective view showing the antenna device, and FIG. 8B is a cross-sectional view taken along the line DD of the antenna device shown in FIG. The antenna device according to the present embodiment shown in FIGS. 8A and 8B includes a third dielectric in addition to the components of the antenna device shown in FIGS. 1 to 3 described in the first embodiment. A fourth dielectric layer 14 provided on the lower surface of the layer 13 and the line conductor 7 (that is, the surface of the third dielectric layer 13 opposite to the first dielectric layer 11), and a fourth dielectric A second electrode pattern 52 provided on the surface of the layer 14 opposite to the third dielectric layer 13 and capable of applying a variable voltage. In the present embodiment, the third dielectric layer 13 includes a variable dielectric constant material. A second DC power source 62 capable of applying a variable voltage is connected to the second electrode pattern 52. Here, in the antenna device shown in FIGS. 8A and 8B, a high frequency signal can be supplied to the slot 3 by supplying a high frequency signal from the RF transmitter 8 to the line conductor 7.

  Also in the antenna device according to the present embodiment shown in FIGS. 8A and 8B, an electric field is generated in the vicinity of the slot 3 by applying a predetermined electric field from the second electrode pattern 52. Here, a first dielectric layer 11 and a third dielectric layer 13 made of a variable dielectric constant material exist in the vicinity of the slot 3. Therefore, the dielectric constant of the dielectric in the slot 3 changes due to the electric field generated in the vicinity of the slot 3. When the dielectric constant in the slot 3 changes, the electrical length of the slot 3 changes, so the frequency characteristic of the slot 3 changes.

  The fourth dielectric layer 14 may be made of a variable dielectric constant material like the second dielectric layer 12, or may be made of a general dielectric such as air. When the fourth dielectric layer 14 is composed of air, the second electrode pattern 52 is provided apart from the third dielectric layer 13. The second electrode pattern 52 may be provided on the same plane as the line conductor 7.

  When the high-frequency signal is fed using the line conductor 7 provided on the lower surface of the third dielectric layer 13 as in the antenna device shown in FIGS. 8A and 8B, the line conductor 7 The RF transmitter 8 and the second DC power source 62 are connected to each other, a high frequency signal is applied from the RF transmitter 8, and a DC voltage (bias) is applied to the line conductor 7 while being superimposed on the line conductor 7. Also good. Thereby, the line conductor 7 can be used as the second electrode pattern 52 while maintaining the function of transmitting a high-frequency signal.

  Moreover, it is preferable to apply a voltage having a polarity opposite to the polarity of the voltage applied to the first electrode pattern 51 to the second electrode pattern 52. This is because an electric field can be effectively generated in the slot 3 by the potential difference between the first and second electrode patterns 51 and 52.

  9 shows a cross section including the line conductor 7 when the first electrode pattern 51 is applied with a potential of −20 V, the second electrode pattern 52 is +20 V, and the ground conductor 4 is 0 V in the antenna device shown in FIG. It is a simulation result of the electric flux density of the electrostatic field in. As shown in FIG. 9, due to the effect of the first electrode pattern 51 to which a potential is applied, an electric field can be generated directly below the radiating element 2 without directly applying a potential to the radiating element 2.

  Therefore, the resonance frequency of the radiating element 2 is changed by adjusting the potential applied to the electrode pattern 51 using the first DC power supply 61 in consideration of the characteristics of the variable dielectric constant material used for the first dielectric layer 11. The operating frequency of the antenna device can be changed to a predetermined frequency.

  An electric field can also be generated inside the slot 3 by the effect of the second electrode pattern 52 to which a potential is applied. Based on the characteristics of the variable dielectric constant materials used for the first and third dielectric layers 11 and 13, the potentials applied to the first and second electrode patterns 51 and 52 are set to the first and second DC power supplies 61 and 62, respectively. By adjusting using, the signal reflected at a predetermined frequency can be minimized, and the best radiation efficiency can be obtained.

  The antenna device according to the present embodiment can also be manufactured using the same method as in the first embodiment. In the structure in which the second electrode pattern 52 is provided, a metal case can be used as in the case of the first embodiment. In this case, an upper surface 51 (corresponding to the first electrode pattern 51) of the metal case covering the variable dielectric constant substrate 11 (corresponding to the first dielectric layer 11) on which the radiating element 2 and the ground conductor 4 are formed. The lower surface 52 (corresponding to the second electrode pattern 52) is insulated, and the first DC power source 61 is connected to the upper surface 51, and the second DC power source 62 is connected to the lower surface 52. At this time, the air layer between the substrate 11 and the metal case corresponds to the second dielectric layer 12 and the fourth dielectric layer 14.

Embodiment 3
Next, a third embodiment of the present invention will be described. The third embodiment of the present invention is an array antenna device in which the antenna devices described in the first and second embodiments are arranged in an array. The characteristics of the array antenna device are required to be equal to the frequency characteristics of each antenna device.

  FIG. 10 is a diagram showing an array antenna apparatus configured by arranging a plurality of antenna apparatuses (see, for example, FIGS. 1 to 3) having the structure described in the first embodiment and the second embodiment. When there are variations in the manufacturing dimensions of the radiating elements 2 of the respective antenna devices, voltages corresponding to the respective radiating elements 2 are connected to the respective first electrode patterns 51 as shown in FIG. The first DC power supply 61 is used. Thus, by adjusting the electrical length of the radiating element 2 of each antenna device, the frequency characteristics of each antenna device can be matched, and the performance as an array antenna device can be improved. That is, according to the invention of this embodiment, when an antenna device is used at a specific frequency, the variation in characteristics of each antenna device that occurs during the manufacturing process is determined by applying the voltage applied to the first electrode pattern 51 of each antenna device. It can be compensated by adjusting.

  FIG. 11 is a diagram showing an array antenna apparatus configured by arranging a plurality of antenna apparatuses (see, for example, FIGS. 1 to 3) having the structure described in the first embodiment and the second embodiment. In the array antenna apparatus shown in FIG. 11, the first electrode patterns 51 of the respective antenna apparatuses are respectively coupled. When all the radiating elements 2 constituting the array antenna device have the same size and the first electrode pattern 51 is similarly arranged with respect to each radiating element 2, the frequency characteristics of each antenna device are similarly changed. The voltage for this is the same. Therefore, as shown in FIG. 11, the first electrode patterns 51 of the respective antenna devices can be combined to have the same potential, and the first DC power supply 61 is combined into one and the frequency characteristics of the entire array antenna. Can be changed. When a plurality of antenna devices described in the second embodiment including the second electrode pattern 52 are arranged, the second electrode pattern 52 can also be combined, and the second DC power supply 62 can be combined into one. it can. Note that the arrangement direction and the interval of the array antenna device are not limited to the configurations shown in FIGS.

  Although the present invention has been described with reference to the above embodiment, the present invention is not limited to the configuration of the above embodiment, and can be made by those skilled in the art within the scope of the invention of the claims of the claims of the present application. It goes without saying that various modifications, corrections, and combinations are included.

2 Radiation element 3 Slot 4 Ground conductor 7 Line conductor 8 RF transmitter 11 First dielectric layer 12 Second dielectric layer 13 Third dielectric layer 14 Fourth dielectric layer 31 Slot line 51 First Electrode pattern 52 Second electrode pattern 61 First DC power supply 62 Second DC power supply

Claims (10)

A first dielectric layer comprising a variable dielectric constant material whose dielectric constant varies with the applied electric field;
A radiating element provided on a first surface of the first dielectric layer;
A ground conductor provided on the second surface of the first dielectric layer and having a slot formed at a position facing the radiating element;
A first electrode pattern provided on the first surface side of the first dielectric layer so as not to overlap with the radiating element in a vertical direction and capable of applying a variable voltage;
Applying a predetermined electric field from the first electrode pattern to the first dielectric layer to change a dielectric constant of the first dielectric layer to change an electrical length of the radiating element;
Antenna device.   The first dielectric layer further includes a second dielectric layer containing a variable dielectric constant material on the first surface, and the first electrode pattern is provided via the second dielectric layer. The antenna device according to claim 1.   The antenna device according to claim 1, wherein the first electrode pattern is provided on the first surface of the first dielectric layer.   2. The antenna device according to claim 1, wherein the first electrode pattern is spaced apart from the first surface of the first dielectric layer via air.   The antenna device according to claim 1, wherein the ground conductor includes a slot line for feeding a high-frequency signal to the slot. A third dielectric layer provided on a surface opposite to the first dielectric layer of the ground conductor;
A line conductor that is provided on a surface of the third dielectric layer opposite to the ground conductor and feeds a high-frequency signal to the slot;
The antenna device according to claim 1. A fourth dielectric layer including a variable dielectric constant material provided on a surface of the ground conductor opposite to the first dielectric layer;
A second electrode pattern provided on the surface of the fourth dielectric layer opposite to the ground conductor and capable of applying a variable voltage;
Changing a dielectric constant in the slot by applying a predetermined electric field from the second electrode pattern;
The antenna device according to claim 1. A fourth dielectric layer provided on a surface of the third dielectric layer opposite to the ground conductor;
A second electrode pattern provided on a surface of the fourth dielectric layer opposite to the third dielectric layer and capable of applying a variable voltage;
The third dielectric layer includes a variable dielectric constant material, and changes a dielectric constant in the slot by applying a predetermined electric field from the second electrode pattern.
The antenna device according to claim 6.   The antenna device according to claim 7 or 8, wherein a polarity of a voltage applied from the second electrode pattern is a polarity opposite to a polarity of a voltage applied from the first electrode pattern.   9. An array antenna device in which a plurality of antenna devices according to claim 1 are arranged.

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