JP2006186969A - Antenna - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a simply manufactured antenna with high directivity capable of realizing good communication quality. <P>SOLUTION: On one surface of the dielectric board 3, antenna 1a is formed so that the 2nd conductor 3 and the 1st conductor 4 may be configured on the same plane. It is desirable that the 1st conductor 4 has a rectangular form with one paired side longer than another paired side, and the 2nd conductor 3 is prepared on the long side of the 1st conductor 4. Further, this 2nd conductor 3 may have notches 6a-6c on the second conductor 3. By carrying out insertion fabrication, the electric supply conductor 2 and is integrally manufactured with the dielectric board 3. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an antenna, and more particularly to an antenna capable of improving directivity in a high frequency band and more accurately forming a desired wide cutoff region.

  In recent years, portable information processing devices having a wireless communication function have been widely used. For wireless communication in such an information processing apparatus, it is essential to mount an antenna in the information processing apparatus. In particular, along with the reduction in size and weight of portable information processing apparatuses, there is a strong demand for development of a small antenna and technical development for improving the antenna performance.

  Until now, various antennas corresponding to the demand for miniaturization have been proposed. For example, there are a monopole antenna and the like that can easily reduce the height and promote miniaturization. The general structure of this monopole antenna is composed of a dielectric substrate standing on the ground plane and a radiation conductor provided on the surface of the dielectric substrate along the vertical direction. A power supply line such as a bull is connected to the lower end of the radiation conductor.

  The monopole antenna as described above can be used in a communication system such as a Broadband-PAN (Personal Area Network) using UWB (Ultra Wide Band) technology, and has a wide frequency band of 3.1 to 10.6 GHz. It can correspond to the radio wave of.

  Similarly to the above, there is an antenna (broadband antenna device) having a structure disclosed in Patent Document 1 as an antenna that can deal with broadband radio waves. Hereinafter, the broadband antenna device will be described with reference to FIG.

FIG. 28 is a perspective view showing a configuration of the broadband antenna device 100. In the broadband antenna device 100, a circular flat radiation conductor 11 is arranged so as to be substantially perpendicular to the surface of the conductor ground plane 12. A gap having an arbitrary height d is provided between the conductor ground plane 12 and the radiation conductor 11, and as shown in FIG. 28, a ground feeding point 12f to the conductor ground plane 12 and a signal feeding point 11f to the radiation conductor 11 are provided. Is provided. Furthermore, as shown in FIG. 28, the circular flat radiation conductor 11 is provided with rectangular cutouts (notches) 11N at two locations on the outer periphery thereof. The notch 11N is provided in the outer peripheral portion of the radiating conductor 11 so as to penetrate the radiating conductor 11, and has a shape having a release port in the outer direction of the outer periphery.
JP 2003-273638 A (published September 26, 2003)

  However, the broadband antenna apparatus 100 as shown in the above prior art has the following problems with respect to directivity. This problem will be described with reference to FIG.

  FIGS. 29A and 29B are diagrams showing a radiation characteristic analysis performed for examining the directivity of the broadband antenna apparatus 100. FIG. FIG. 29A is a diagram schematically showing a three-dimensional direction provided in the broadband antenna device 100 for performing the radiation characteristic analysis. FIG. 29B is a diagram showing a result of radiation characteristic analysis of the broadband antenna device 100 based on the three-dimensional direction shown in FIG. This radiation characteristic analysis is composed of the YZ plane composed of the Y axis and the Z axis, the XZ plane composed of the X axis and the Z axis, and the X axis and the Y axis shown in FIG. The following polarized waves (1) to (3) were used as radiated radio waves for the YZ plane, the XZ plane, and the XY plane. That is, (1) For the YZ plane, the polarization perpendicular to this plane (V polarization) and the horizontal polarization (H polarization), and (2) For the XZ plane, the polarization perpendicular to this plane ( V polarization), horizontal polarization (H polarization), and (3) XY plane radiates polarization perpendicular to this plane (V polarization) and horizontal polarization (H polarization). Used as radio waves. Furthermore, it performed using the radiation wave of 3 types of frequencies, 3GHz, 4GHz, and 6GHz per each surface. In the analysis result of FIG. 29B, the thin line indicates the H polarization analysis result, and the thick line indicates the V polarization analysis result.

  From FIG. 29 (b), it can be seen that in the above (1) YZ plane, the radiated radio wave is limited to H polarization. Similarly, also in the above (2) XY plane, the radiated radio wave is limited to H polarization. From this analysis result, it can be said that the broadband antenna apparatus 100 is likely to change the communication quality due to a change in the installation angle of the antenna.

  That is, it can be said that the broadband antenna device 100 has a limitation in the degree of freedom of installation.

  Furthermore, the analysis results at the frequency of 6 GHz on the above (1) YZ plane and (2) XY plane show that in these cases, radiation to the back surface of the conductor ground plane 12 is suppressed (FIG. 29B). ) Inside broken line). This is because of the conductor ground plane 12. Therefore, in the wideband antenna device 100 configured as described above, the radiation level to the conductor ground plane back surface is suppressed, particularly in the high frequency band, and a communication area in that direction cannot be secured. That is, it can be said that the wideband antenna device 100 has poor directivity and cannot achieve good communication quality.

  Further, as shown in FIGS. 28 and 29, the broadband antenna device 100 has a configuration in which the radiation conductor 11 stands up with respect to the conductor ground plane 12, so that the antenna itself inevitably has a three-dimensional shape and is large in size. , Sometimes unwieldy. Also in the production, it is difficult to make the radiation conductor 11 stand on the conductor ground plane 12, that is, to automatically mount the radiation conductor 11 on the conductor ground plane 12. Therefore, in order to erect the radiation conductor 11 on the conductor base plate 12, it has been necessary to perform soldering manually. Therefore, since such a complicated process is required, the broadband antenna device 100 lacks mass productivity.

  Therefore, the present invention has been made in view of the above-described problems, and an object of the present invention is to provide an antenna that has good directivity, can realize good communication quality, and can be easily manufactured. It is to provide.

  In order to solve the above problems, an antenna according to the present invention includes a first conductor and a second conductor having different shapes, and a power feeding unit that feeds power to the first conductor and the second conductor. The one conductor and the second conductor are arranged so that their surfaces are parallel to each other.

  According to said structure, the 1st conductor and the 2nd conductor are comprised in parallel. Thereby, compared with the prior art, directivity is better in the high frequency band. Therefore, the antenna of the present invention can improve the degree of freedom of installation and can maintain good communication quality even when the installation angle varies.

  When the configuration of the present invention is made to correspond to the configuration of the broadband antenna device in the prior art, the first conductor of the present invention can be a conductor ground plane in the prior art, and in this case, the second conductor is a circular shape in the prior art. Radiating conductors. In this case, the structure of the present invention is different from the structure of the prior art, and the first conductor (conductor ground plane) and the second conductor (circular radiation conductor) are configured on the same plane. Since the first conductor and the second conductor are configured on the same plane, detailed analysis results will be shown in an embodiment to be described later. To the back of the first conductor (conductor ground plane) that has been a problem in the prior art Therefore, it is possible to secure a communication area in the direction in which the radiation is conventionally suppressed.

  That is, it can be said that the antenna of the present invention has better directivity (approaches omnidirectionality) compared to the prior art.

  Therefore, the antenna of the present invention can improve the degree of freedom of installation as compared with the conventional broadband antenna device, and the effect that the communication quality is not easily changed even when the installation angle changes. Play.

  Further, according to the present invention, unlike the structure of the prior art, it is a planar structure, so that a reduction in thickness can be realized. In addition, since it can be thinned, it can be installed in a thin device such as a mobile device, or can be installed in a narrow gap of other devices. Furthermore, the substrate can be integrated with other circuits.

  In addition, the antenna of the present invention does not require a complicated process of standing up in the manufacturing process unlike the prior art. Therefore, mass productivity can be improved and a reduction in manufacturing cost can be realized.

  Moreover, it is preferable that the antenna according to the present invention is configured such that the first conductor and the second conductor are flush with each other via the feeding portion.

  The term “equal” includes a completely flush state and a substantially flush state.

  In the antenna according to the present invention, the first conductor and the second conductor are formed on a substrate, and a dielectric layer made of a dielectric material having a dielectric constant higher than that of the substrate is at least the above-mentioned It is preferable to be provided so as to cover the second conductor.

  By setting it as said structure, a board | substrate can be comprised from a general purpose dielectric constant material.

  That is, the substrate can be made of a general-purpose dielectric constant material by providing at least the second conductor with a dielectric made of a dielectric material having a dielectric constant higher than that of the substrate. Thereby, the antenna of the present invention can be realized at low cost.

  In addition, by covering the dielectric layer with a high dielectric constant in this way, the wavelength shortening effect can be utilized even when the substrate is made of a general-purpose dielectric constant material. Miniaturization can be realized. The wavelength shortening effect is an effect that the wavelength of the electromagnetic wave transmitted through the dielectric is shortened according to the value of the dielectric constant.

  In the antenna according to the present invention, the first conductor is formed on the surface of the first substrate, and the second conductor is configured to be flush with the surface of the first substrate. It is preferably formed on the surface of the second substrate made of a dielectric material having a dielectric constant higher than that of the first substrate.

  With the above configuration, only the portion of the substrate (second substrate) on which the second conductor is formed is formed of a dielectric made of a dielectric material having a high dielectric constant, and the other portion of the substrate (the first conductor is The first substrate to be formed can be made of a general dielectric constant material.

  Thereby, the antenna of the present invention can be realized at low cost.

  Moreover, since the wavelength shortening effect can be utilized by using a dielectric material having such a high dielectric constant, the antenna of the present invention can be miniaturized.

  In the antenna according to the present invention, the first conductor is formed on the surface of the first substrate, and the second conductor is configured to be flush with the surface of the first substrate. It is preferably formed on the surface of the second substrate made of a dielectric material having a dielectric constant higher than that of the first substrate.

  Thereby, in addition to the above effect, the first conductor and the first substrate, and the second conductor and the second substrate can be manufactured separately. Thereby, even if one configuration (for example, the shape of the first conductor) is changed, it is not necessary to change the production line greatly, and it is possible to cope with it efficiently.

  In the antenna according to the present invention, the first conductor is formed on the surface of the first substrate, and the second conductor has a smaller area than the first conductor and an area smaller than the first substrate. It is formed on the surface of a small second substrate, and the second substrate is higher than the dielectric constant of the first substrate laminated on the surface of the first substrate where the first conductor is not formed. It is preferably made of a dielectric material having a dielectric constant.

  Thereby, in addition to the above effect, the first conductor and the first substrate, and the second conductor and the second substrate can be manufactured separately. Thereby, even if one configuration (for example, the shape of the first conductor) is changed, it is not necessary to change the production line greatly, and it is possible to cope with it efficiently.

  Further, in the antenna according to the present invention, the first conductor has a rectangular shape in which one of the two adjacent sides is longer than the other side, and the power feeding portion is connected to the first conductor. It is preferable to be provided on one long side.

  Further, in the antenna according to the present invention, the area of the second conductor is smaller than that of the first conductor, and the power feeding unit is configured such that the second conductor is in one end region on one long side of the first conductor. It is preferable to be provided.

  With the above configuration, the second conductor is disposed in any one end region on the long side of the first conductor, that is, the second conductor is transverse to the center of the long side of the first conductor. Can be offset. Thereby, current distribution in the long side direction is generated on the first conductor, and not only the second conductor but also the first conductor can be operated as an antenna.

  Specifically, when a three-dimensional direction is schematically formed in the antenna of the present invention corresponding to the configuration of the broadband antenna device in the prior art, a polarization component perpendicular to the YZ plane is radiated omnidirectionally in the YZ plane. it can. This is a polarization component radiated by a current distribution generated in the long side direction on the first conductor. This polarization component is a polarization component that cannot be generated by the monopole antenna or the broadband antenna device described above.

  Therefore, by adopting such a configuration, it is possible to prevent extreme deterioration in communication quality when the antenna installation angle changes, and as a result, the degree of freedom of antenna installation can be further improved.

  In the antenna according to the present invention, it is preferable that the second conductor has a circular shape.

  By making the second conductor into a circular shape, the antenna of the present invention can obtain broadband characteristics.

  In the antenna according to the present invention, it is preferable that a cutout portion is provided in at least one of the first conductor and the second conductor.

  According to said structure, the antenna of this invention can adjust the frequency characteristic of the said antenna by controlling appropriately the flow of the high frequency current on a 1st conductor in addition to said effect. This reduces interference from unnecessary frequency bands and interference to undesired frequency bands.

  That is, according to the above configuration, unnecessary frequency bands and unintended frequency bands can be blocked.

  Specifically, as described above, in the case of a communication method such as UWB, coexistence with other radio systems is necessary, and consideration is given to interference received from other radio systems and interference given to other radio systems. is required.

  In order to reduce such interference and interference, a general antenna requires some filter means such as a band elimination filter and a bandpass filter after the antenna. However, adding a filter contradicts the demand for downsizing and cost reduction of wireless communication devices. In addition, degradation of characteristics such as a decrease in reception sensitivity is caused by in-band insertion loss of the inserted filter itself. Therefore, according to the antenna of the present invention, since the notch portion is provided in at least one of the first conductor and the second conductor, it is adjusted to the target frequency characteristic, and from an unnecessary frequency band. It is possible to reduce interference and interference with an unintended frequency band.

  In addition, since the frequency characteristics can be adjusted to the target characteristics, it is possible to eliminate the need for the band limiting filter or to relax the required specifications for the band limiting filter, and to implement the antenna of the present invention. Miniaturization, price reduction, and high performance of a wireless communication device can be realized.

  In the antenna according to the present invention, it is preferable that the notch has a circular shape.

  With the above configuration, a wide range of frequency bands can be blocked.

  Specifically, in the UWB standard, in addition to a method of performing communication using all bands (full band) of 3.1 GHz to 10.6 GHz, a band already used in a 5 GHz wireless LAN is used. Avoiding the communication by dividing the band into 3.1 GHz to 4.9 GHz (Low Band) and 5.8 GHz to 10.6 GHz (High Band). .

  When performing UWB communication in the low band, the antenna has a characteristic that the pass band is 3 to 5 GHz, and the other band is the cut-off band, and the antenna rises sharply in the vicinity of 3 GHz and 5 GHz, which are the boundaries between the pass band and the cut-off band It is desirable to have characteristics.

  In low-band communication, signals other than those in the 3.1 GHz to 4.9 GHz band become noise, and therefore, it is necessary to filter and eliminate entry into the receiving circuit.

  When a full-band (3 to 10 GHz) antenna is used, it is necessary to insert a filter in the receiving circuit. However, according to the antenna having the above characteristics, the antenna itself has a filter rig function. There is no need to insert a member, and there is an advantage that simplifies the configuration of the high-frequency module and reduces the cost.

  In the prior art wideband antenna device, for example, it has been shown that a specific frequency (depending on the length of the cutout rectangle) can be cut off by providing a rectangular cutout in a circular radiating conductor having wideband characteristics. . However, since the band that can be cut off by this method is narrow, it is practically difficult to form a wide cut-off area (about 5 to 10 GHz) necessary as a low-band antenna.

  In contrast, the inventors of the present application have found that the cut-off area can be widened by making the notch circular.

  Moreover, it is preferable that the antenna which concerns on this invention is provided with several said notch parts from which an area mutually differs.

  By adopting the above configuration, in addition to the above effects, a desired wide cutoff region can be formed more accurately.

  Specifically, when performing UWB communication in the low band as described above, the signal in the band other than 3.1 GHz to 4.9 GHz becomes noise, so that it is necessary to accurately set this as a cut-off area. So, according to said structure, since the antenna of this invention is provided with the said some notch part from which an area differs, it can interrupt | block the signal of bands other than 3-5 GHz reliably. Therefore, a target frequency band can be accurately provided to a wireless device or the like on which an antenna is mounted.

  As described above, the antenna of the present invention includes the first conductor and the second conductor having different shapes, and the power feeding unit that feeds power to the first conductor and the second conductor. The second conductor is characterized in that each surface is arranged in parallel to each other.

  According to said structure, the 1st conductor and the 2nd conductor are comprised in parallel with each other. As a result, there is provided an antenna capable of improving directivity even in a high-frequency band, improving the degree of freedom of installation, and maintaining good communication quality even when the installation angle varies. be able to.

[Embodiment 1]
The embodiment according to the present invention will be described below with reference to FIGS.

  In the following, for convenience of explanation, the antenna characteristics and the like will be described assuming that electromagnetic waves are transmitted using the antenna 1a. However, these characteristics and the like are almost the same even when the electromagnetic waves are received using the antenna 1a. The same holds true. That is, the antenna 1a can be used for both electromagnetic wave transmission and reception.

  FIG. 1 is a perspective view showing a configuration of an antenna 1a in the present embodiment. As shown in FIG. 1, the antenna 1a has a flat plate shape.

  In this specification, the ratio of the dielectric constant ε1 of the dielectric substrate (substrate) 2 to the dielectric constant ε0 of the space (external space, usually the air layer) in which electromagnetic waves are radiated from the antenna 1a, that is, ε1 / ε0. Is defined as the relative dielectric constant of the dielectric substrate 2.

  The configuration of the antenna 1a will be specifically described with reference to FIG.

  As shown in FIG. 1, the antenna 1 a according to the present embodiment includes a dielectric substrate 2, a second conductor 3, a first conductor 4, and a feeding terminal region (feeding portion) 5.

  The second conductor 3 and the first conductor 4 are formed on one surface of the dielectric substrate 2 so as to be configured on the same plane.

  The dielectric substrate 2 is made of a dielectric, and the outer shape defines the size of the antenna 1a. As shown in FIG. 1, the dielectric substrate 2 (antenna 1a) of the present embodiment has a rectangular flat plate shape.

  In addition, as a material used for the dielectric substrate 2, for example, there is a material having a high dielectric constant such as a relative dielectric constant εr = 15. By using a material having a high dielectric constant as the dielectric substrate 2, a wavelength shortening effect can be obtained. This wavelength shortening effect is an effect that the wavelength of the electromagnetic wave transmitted through the dielectric is shortened according to the value of the dielectric constant. If this effect is used, when considering an antenna operating at the same frequency, an antenna having a higher substrate dielectric constant can be made smaller than an antenna having a lower dielectric constant. Therefore, the antenna 1a using a high dielectric constant material can be reduced in size.

  Moreover, the dielectric substrate 2 can be formed from resin, for example. Examples of the resin include polyethersulfone (PPS), liquid crystal polymer (LCP), syndiotactic polystyrene (SPS), polycarbonate (PC), polyethylene terephthalate (PET), epoxy resin (EP), polyimide resin (PI), poly Etherimide resin (PEI), phenol resin (PF), or the like can be used. When the dielectric substrate 2 is made of a high dielectric constant material having a relative dielectric constant εr = 15, it is preferable to use a material having a high dielectric constant such as PPS or LCP.

  The first conductor 4 is an electrode made of a conductor. The first conductor 4 has a so-called rectangular shape in which one of the two pairs of opposite sides is longer than the other. A region 4 </ b> V connected to the power supply terminal region 5 is provided at one central portion of the longer side (hereinafter, referred to as a long side) of the first conductor 4. The first conductor 4 can be configured using, for example, a metal material.

  The second conductor 3 is an electrode made of a conductor and has a circular shape. The second conductor 3 is connected to the power supply terminal region 5 provided at the center of one of the long sides of the first conductor 4 in the region 3V. Since the second conductor 3 has a circular shape, the antenna 1a can have broadband characteristics. For example, a metal material can be used as the second conductor 3.

  In the second conductor 3 and the first conductor 4, a current distribution corresponding to each shape and size is generated on each conductor, and a radio wave having a pattern determined by the current distribution is irradiated.

  FIG. 2 is a cross-sectional view taken along the line A-A ′ in FIG. 1, showing the antenna 1 a as viewed from the direction of the arrow. As shown in FIG. 2, the feeding terminal area 5 is provided between the area 3 </ b> V of the second conductor 3 and the area 4 </ b> V of the first conductor 4. The power supply terminal area 5 is connected to a power supply terminal and a power supply line (not shown).

  As described above, in the antenna 1a, as shown in FIGS. 1 and 2, the second conductor 3 and the first conductor 4 are formed on the same surface on the dielectric substrate 2. Thus, unlike the conventional wideband antenna and monopole antenna, the flat (flat) structure is used, so that the thickness can be reduced.

  In addition, since it can be thinned, it can be installed in a thin device such as a mobile device, or can be installed in a narrow gap of other devices. Furthermore, the substrate can be integrated with other circuits.

  Next, the directivity of the antenna 1a in the present embodiment will be described based on FIGS. 3 (a) and 3 (b).

  FIGS. 3A and 3B are diagrams showing the analysis results of the radiation characteristic analysis performed for examining the directivity of the antenna 1a having the above-described configuration.

  FIG. 3A is a perspective view schematically showing a three-dimensional direction provided in the antenna 1a when performing the radiation characteristic analysis. As shown in FIG. 3A, the Y axis is formed in the diameter direction of the second conductor 3 with the feeding terminal region 5 as the starting point, and the X axis is set in the long side direction of the first conductor 4 with the feeding terminal region 5 as the starting point. The Z axis is formed in the vertical direction from the XY plane composed of the Y axis and the X axis.

  FIG. 3B is a diagram showing an analysis result of the radiation characteristic analysis of the antenna 1a based on the three-dimensional direction shown in FIG. In this radiation characteristic analysis, the YZ plane constituted by the Y axis and the Z axis, the XZ plane constituted by the X axis and the Z axis, and the X axis and the Y axis shown in FIG. The following polarized waves (1) to (3) were used as radiated radio waves for the YZ plane, the XZ plane, and the XY plane. That is, (1) For the YZ plane, the polarization perpendicular to this plane (V polarization) and the horizontal polarization (H polarization), and (2) For the XZ plane, the polarization perpendicular to this plane ( V polarization), horizontal polarization (H polarization), and (3) XY plane radiates polarization perpendicular to this plane (V polarization) and horizontal polarization (H polarization). Used as radio waves. Furthermore, it performed using the radiation wave of 3 types of frequencies, 3GHz, 4GHz, and 6GHz per each surface. In the analysis result of FIG. 3B, the thin line indicates the H polarization analysis result, and the thick line indicates the V polarization analysis result.

  From the analysis result of FIG. 3B, it can be seen that suppression of radio wave radiation, which has been a problem in the conventional broadband antenna device shown in FIG. 29B, has not occurred. That is, as described above, in the case of the above prior art, among the analysis results shown in FIG. 29 (b), when (1) YZ plane and (2) radiated radio waves having a frequency of 6 GHz on the XY plane are used. Since there is the conductor ground plane 12 (FIG. 28), the radiation to the back surface of the conductor ground plane 12 is suppressed (inside the broken line in FIG. 29B). Therefore, in the wideband antenna device 100 configured as described above, the radiation level to the back surface of the conductor base plate 12 is suppressed particularly in the high frequency band, and a communication area in that direction cannot be secured. Then, when the same radiation characteristic analysis as the prior art was performed using the antenna 1a of the present embodiment, as shown in FIG. 3B, a high frequency of 6 GHz on the (1) YZ plane and (3) XY plane. Even in the band, the radio wave is radiated in the direction in which the radiation is suppressed in the conventional broadband antenna device.

  Thereby, the antenna of this invention can ensure the communication area | region to the direction where radiation was suppressed conventionally. That is, it can be said that the antenna of the present invention has better directivity (approaches omnidirectionality) than the prior art.

  In addition, conventionally, as shown in FIG. 29B, it can be seen that the radiated radio wave is limited to the horizontally polarized wave on the (1) YZ plane. Similarly, for the above (3) XY plane, the radiated radio wave is limited to horizontal polarization. Thereby, it can be said that the broadband antenna device 100 (FIG. 28) is likely to change the communication quality due to a change in the installation angle of the antenna. That is, the wideband antenna device 100 has a limitation in the degree of freedom of installation. On the other hand, in the antenna 1 of this embodiment, for example, as seen in (3) XY plane, the radiated radio wave differs from the conventional one, and vertically polarized waves are also radiated.

  From the above, the antenna 1a in the present embodiment can improve the degree of freedom of installation as compared with the conventional broadband antenna device 100 (FIG. 28), and the installation angle varies. In addition, the communication quality can be maintained well.

  In order to manufacture such an antenna 1a, a process of forming the dielectric substrate 2 into a predetermined shape, a step of plating, a step of masking, a step of electrolytic plating, a step of removing the mask, and a step of etching are performed. Conventional manufacturing techniques can be used.

  Therefore, in the conventional broadband antenna device 100 (FIG. 28), a complicated process such as a manual soldering process when the radiating conductor 11 is erected on the conductor base plate 12 as described above is necessary. On the other hand, since the antenna of the present invention has a planar structure, it can be easily manufactured without using the complicated steps described above. Therefore, mass productivity can be improved, and accordingly, manufacturing cost can be reduced.

  Note that the antenna 1a described above has a configuration in which only the second conductor 3, the first conductor 4, and the feeding terminal region 5 are provided on the dielectric substrate 2 for convenience of explanation, but the present invention is not limited thereto. For example, a protective layer that protects the second conductor 3, the first conductor 4, and the power supply terminal region 5 may be provided.

[Embodiment 2]
Another embodiment of the antenna according to the present invention will be described below with reference to FIGS.

  In the present embodiment, in order to explain the difference from the first embodiment, for convenience of explanation, members having the same functions as those described in the first embodiment are denoted by the same reference numerals, The description is omitted.

  FIG. 4 is a perspective view showing the configuration of the antenna 1b in the present embodiment. In the first embodiment, the feeding terminal region 5 is provided at the center of the long side of the first conductor 4. That is, the second conductor 3 is disposed at the center of the long side of the first conductor 4. On the other hand, in the antenna 1b of the present embodiment shown in FIG. 4, the feeding terminal region 5 is provided in one of the end regions from the center of the long side of the first conductor 4, and the feeding terminal region 5 In addition, the second conductor 3 is connected. That is, the antenna 1b according to the present embodiment has a configuration in which the second conductor 3 is shifted from the center of the long side of the first conductor 4 to any one end region.

  By arranging the second conductor 3 so as to be shifted from the center of the long side of the first conductor 4 to one of the end regions, a current distribution in the long side direction can be generated on the first conductor 4. And radiated radio waves caused by this current can be generated. That is, not only the second conductor 3 but also the first conductor 4 can be operated as an antenna.

  Next, the directivity of the antenna 1b according to the present embodiment will be described with reference to FIGS.

  FIGS. 5A and 5B are diagrams showing the results of the radiation characteristic analysis performed for examining the directivity of the antenna 1b having the above-described configuration.

  FIG. 5A is a perspective view schematically showing a three-dimensional direction provided in the antenna 1b when performing the radiation characteristic analysis. As in the first embodiment, the Y-axis is formed in the diameter direction of the second conductor 3 starting from the center of the long side of the first conductor 4, and the first conductor starting from the center of the long side of the first conductor 4. The X axis is formed in the long side direction of 4, and the Z axis is formed in the vertical direction from the XY plane composed of the Y axis and the X axis.

  FIG. 5B is a diagram showing an analysis result of the radiation characteristic analysis of the antenna 1b based on the three-dimensional direction shown in FIG.

  In this radiation characteristic analysis, the YZ plane composed of the Y axis and the Z axis, the XZ plane composed of the X axis and the Z axis, and the XY composed of the X axis and the Y axis shown in FIG. The following polarized waves (1) to (3) were used as radiated radio waves for the YZ plane, the XZ plane, and the XY plane. That is, (1) For the YZ plane, the polarization perpendicular to this plane (V polarization) and the horizontal polarization (H polarization), and (2) For the XZ plane, the polarization perpendicular to this plane ( V polarization), horizontal polarization (H polarization), and (3) XY plane radiates polarization perpendicular to this plane (V polarization) and horizontal polarization (H polarization). Used as radio waves. Furthermore, it performed using the radiation wave of 3 types of frequencies, 3GHz, 4GHz, and 6GHz per each surface. In the analysis result of FIG. 5B, the thin line indicates the H polarization analysis result, and the thick line indicates the V polarization analysis result.

  From the analysis result of FIG. 5B, compared with the analysis result shown in FIG. 3B of the first embodiment, (1) the vertical polarization component in the YZ plane is omnidirectional in the YZ plane. It can be seen that This radiation is a polarization component radiated by the current distribution generated in the long side direction on the first conductor 4. This polarization component is a polarization component that cannot be generated by the conventional monopole antenna or the broadband antenna device described above.

  Here, the antenna shown in FIGS. 6A and 6B will be described as a comparison with the antenna 1b. While the feeding terminal region 5 and the second conductor 3 in the first embodiment (FIG. 1) and the present embodiment (FIG. 4) are provided on the long side of the first conductor 4, FIG. In the perspective view of the antenna shown in a), the feeding terminal region 50 and the second conductor 30 are provided on the short side (hereinafter referred to as the short side) of the first conductor 40. FIG. 6B is a diagram showing the result of the radiation characteristic analysis performed for examining the directivity of the antenna shown in FIG. 6A, similarly to FIG. 5B. From the analysis results, the component of the vertically polarized wave on the (1) YZ plane in FIG. 6B is smaller than that in FIG. 5B. Therefore, as shown in FIG. When the second conductor 3 is formed on the short side of the conductor 4, a sufficient current distribution does not occur in the X-axis direction shown in FIG. 6A, and the polarization component caused by this current is also shown in FIG. (1) It can be seen that it is smaller than the vertically polarized component of the YZ plane.

  That is, in order to generate a sufficient current distribution in the X-axis direction and to generate a polarization component caused by this current, which cannot be generated by the monopole antenna or the broadband antenna device described above, as shown in FIG. In addition, the second conductor 3 may be configured to be shifted to any one end region from the center of the long side of the first conductor 4.

  With this configuration, the above-described polarization component can be generated, and the presence of this polarization component can prevent extreme deterioration in communication quality when the antenna installation angle changes. Become. Therefore, as a result, the degree of freedom of antenna installation can be further improved.

  The size of the antenna 1b in this embodiment can be set as appropriate based on the relationship with the device to be mounted. An example is shown in FIG. As shown in FIG. 7, the outer shape of the antenna 1b (dielectric substrate 2) can be 20 mm × 30 mm, and the thickness of the dielectric substrate 2 can be 1 mm. In this case, it is preferable that the diameter of the second conductor 3 is 10 mm, and the center of the second conductor 3 is arranged about 5 mm from the 20 mm side of the antenna 1b.

  In addition, by making the second conductor 3 circular, it is possible to realize a wide band of the antenna 1b as in the first embodiment. However, in the present embodiment, the shape of the second conductor 3 is circular, but the present invention is not limited to this. For example, it may have an elliptical shape as shown in FIG. 8 (a), or may have a shape as shown in FIGS. 8 (b) to (o). For convenience of explanation, the power supply terminal portion is not provided in FIG. In addition, the radiation conductor of the shape shown to Fig.8 (a)-(o) is applicable also to the radiation conductor in the said Embodiment 1. FIG. In FIGS. 8A to 8O, only the member numbers of the second conductors 3 are given for convenience of explanation.

  Further, the first conductor 4 also has a rectangular shape in the present embodiment, but as described above, a current distribution in the long side direction is generated on the first conductor 4 and is caused by this current. There is no limitation on the shape of the radiation wave if it can be generated. Therefore, for example, the first conductor 4 having a shape as shown in FIGS. In addition, in FIG. 9 (a)-(i), the member number only of the 1st conductor 4 is attached | subjected for convenience of explanation.

[Embodiment 3]
Another embodiment of the antenna according to the present invention will be described below with reference to FIGS. 10 and 17.

  In the present embodiment, in order to explain the difference from the first embodiment, for convenience of explanation, members having the same functions as those described in the first embodiment are denoted by the same reference numerals, The description is omitted.

  FIG. 10 is a perspective view showing the shape of the antenna 1c in the present embodiment. In the first embodiment and the second embodiment, the second conductor 3 is a flat plate having a circular shape. On the other hand, in the antenna 1c of the present embodiment shown in FIG. 10, the feeding terminal region 5 is offset from the center of the long side of the first conductor 4, and further, a notch is formed in the second conductor 3 ″. 6a-6c are provided.

  The notches 6a to 6c have a circular shape. Further, the notch 6a, the notch 6b, and the notch 6c have different diameters.

  Next, the S11 characteristic of the antenna 1c in the present embodiment will be described with reference to FIG. FIG. 11 is a graph showing a result of measuring the S11 characteristic of the antenna 1c in the present embodiment.

  S11 is the input reflection coefficient of the antenna. The smaller S11 (−∞), the smaller the reflection from the antenna input end, and the less power is transmitted to the antenna without any loss. Conversely, S11 is 0 dB. In this case, it means that it is completely reflected at the antenna input end and is not transmitted to the antenna. If S11 is smaller than −10 dB, it can be said that the antenna functions as a large obstacle.

  From the result of FIG. 11, in the antenna 1c of the present embodiment, S11 is −10 dB or less in the band near the frequency of 3.0 GHz to 5.0. That is, it can be said that the antenna 1c according to the present embodiment can function without significant trouble as an antenna in this band. In other words, in the antenna 1c of this embodiment, reflection occurs at the antenna input end in a band other than the vicinity of the frequency of 3.0 GHz to 5.0. That is, the antenna 1c according to the present embodiment blocks a band other than the frequency near 3.0 GHz to near 5.0.

  As in the first embodiment, for example, a material having a high dielectric constant such as a relative dielectric constant εr = 15 can be used for the second conductor 3 ″.

  Each of the notches 6a to 6c will be specifically described below with reference to FIGS. 12 (a) and 12 (b) to 14 (a) and (b).

  12A is a perspective view showing a configuration in which the second conductor 3 ″ is offset from the center of the long side of the first conductor 4 and only the notch 6a is provided. 12 (b) is a diagram showing a result of measurement on the S11 characteristic of the antenna 1c of FIG. 12 (a). Also, FIG. 13 (a) shows that the second conductor 3 ″ is the length of the first conductor 4. It is the perspective view which showed the structure offset only from the center of a side and having only the notch part 6b. FIG. 13B is a diagram showing a result of measuring the S11 characteristic of the antenna 1c of FIG. From FIG. 12 (b), in the antenna 1c provided with the second conductor 3 ″ provided with only the notch 6a, S11 is −10 dB or more in the frequency band from about 5.0 GHz to about 7.0. That is, the antenna 1c of the present embodiment is that reflection occurs at the antenna input end in this band, and it can be said that this band is cut off. In the antenna 1c provided with the second conductor 3 ″ provided with only the notch 6b, S11 is −10 dB or more in a frequency band of about 8.0 GHz to 10.0 GHz. That is, the antenna 1c of the present embodiment is that reflection occurs at the antenna input end in this band, and it can be said that this band is cut off. FIG. 14A shows a case where the second conductor 3 ″ is offset from the center of the long side of the first conductor 4 and has a notch 6a and a notch 6b. The S11 characteristic of the antenna 1c is measured. Fig. 14 (b) is a diagram showing the S11 characteristic measurement result of the antenna 1c including the notch 6a and the second conductor 3 "provided with the notch 6b. is there. From FIG.14 (b), in the antenna 1c shown to Fig.14 (a), S11 is -10 dB or more in the zone | band of frequency 5.0 GHz or more. That is, the antenna 1c of the present embodiment is that reflection occurs at the antenna input end in this band, and it can be said that this band is cut off.

  Here, there is a band P in which the S11 characteristic is reduced in the vicinity of 5.5 GHz in FIG. As shown in FIG. 11, if the antenna 1c of the present embodiment also includes the notch 6c, there is no decrease in the band P.

  As described above, the antenna 1c according to the present embodiment can cut off the band other than the frequency band near 3.0 GHz to 5.0.

  In the case of a communication system such as UWB, it is necessary to coexist with other radio systems, and it is necessary to consider interference received from other radio systems and interference given to other radio systems.

  In order to reduce such interference and interference, a general antenna requires some filter means such as a band elimination filter and a bandpass filter after the antenna. However, adding a filter contradicts the demand for downsizing and cost reduction of wireless communication devices. In addition, degradation of characteristics such as a decrease in reception sensitivity is caused by in-band insertion loss of the inserted filter itself. Therefore, according to the antenna of the present embodiment, since a specific band can be cut off, it is necessary to coexist with other wireless systems when the antenna 1c is used for a communication method such as UWB. Even in this case, it is possible to suppress the interference received from other radio systems and the interference given to other radio systems.

  By the way, in recent years, as described above, in addition to a method of performing communication using all bands (full band) of 3.1 GHz to 10.6 GHz, it is already used in a 5.0 GHz wireless LAN. It is also considered to perform communication by dividing the band into 3.1 GHz to 4.9 GHz band (Low Band) and 5.8 GHz to 10.6 GHz (High Band) avoiding the band. ing.

  Therefore, when the antenna 1c of the present embodiment is used, when performing UWB communication in a low band, the antenna can pass from 3.1 GHz to 4.9 GHz, and other bands can be used as a cutoff band. it can.

  Furthermore, in antenna 1c of the present embodiment, as shown in FIG. 11, S11 rises steeply in the vicinity of 3.0 GHz and 5.0 GHz, which are the boundaries between the passband and the cut-off zone. As described above, when performing UWB communication in a low band, noise (signals in a band other than 3.1 GHz to 4.9 GHz) to the receiving circuit is obtained by having a steep rise characteristic in the vicinity of 3.1 GHz and 4.9 GHz. ) Can be accurately blocked, so that communication quality can be improved.

  As described above, according to the antenna 1c, since the notch is provided in the second conductor 3 ″, it is adjusted to the target frequency characteristics, interfered from unnecessary frequency bands, and undesired frequencies. The interference to the band can be reduced.

  In addition, since the frequency characteristics can be adjusted to the desired characteristics, the band limiting filter can be made unnecessary, or the required specifications for the band limiting filter can be relaxed, and a radio communication apparatus mounted with an antenna It is possible to achieve downsizing, cost reduction, and high performance.

  Further, as shown in FIG. 10, in the antenna 1 c in the present embodiment, the second conductor 3 ″ provided with the notches 6 a to 6 c is offset from the center of the long side of the first conductor 4. As a result, a current distribution in the long side direction can be generated on the first conductor 4, and a radiated radio wave due to this current can also be generated.

  As shown in FIG. 10, in the antenna 1c in the present embodiment, the notches 6a to 6c have a circular shape, but the present invention is not limited to this. For example, it may be a notch having a shape as shown in FIGS. 15 (a) and 16 (a). 15A has hexagonal notches 6a 'to 6c', and FIG. 16A has elliptical notches 6a "to 6c". When the S11 characteristic of the antenna 1c in the case of having a cutout portion as shown in FIGS. 15A and 16A is measured, it is as shown in FIGS. 15B and 16B.

  From FIG. 15B and FIG. 16B, it can be seen that S11 characteristics similar to those of the antenna 1c in the present embodiment provided with the cutout portions 6a to 6c having a circular shape are shown.

  Therefore, the shape of the cutout portion 6c of the antenna 1c is not limited as long as it can exhibit the same S11 characteristic as described above. In addition to the above, a notch having a shape as shown in FIG. FIG. 17A shows the shape of the notch, and the number of notches is not limited to one pair (two).

  In addition, the second conductor 3 is configured so as to be shifted from the center of the long side of the first conductor 4 to either one of the end regions, and a current distribution in the long side direction is generated on the first conductor 4. Since the radiated radio wave caused by this current can also be generated, the notches 6a to 6c may be provided in the first conductor 4 as shown in FIG.

  Further, by making the second conductor 3 ″ circular, it is possible to realize a wide band of the antenna 1c as in the first embodiment. However, as described in the second embodiment, the second embodiment. The shape of the second conductor 3 ″ can also be the shape shown in FIGS.

  In addition, the first conductor 4 of the present embodiment is not limited in shape as in the second embodiment, and is, for example, a conductor having a shape as shown in FIGS. Also good.

[Embodiment 4]
Another embodiment of the antenna according to the present invention will be described below with reference to FIGS. In the present embodiment, in order to explain the difference from the third embodiment, for the sake of convenience of explanation, members having the same functions as those described in the third embodiment are denoted by the same reference numerals, The description is omitted.

  In the third embodiment, a material having a high dielectric constant such as a relative dielectric constant εr = 15 is used as the dielectric substrate 2. However, such a high dielectric constant material is not general-purpose. Therefore, if a general-purpose material having a relative dielectric constant not so high is used, further cost reduction can be realized.

  Accordingly, the inventors of the present application measured each cut-off area due to the difference in relative permittivity of the dielectric substrate 2 as the S11 characteristic for the antenna 1c having the configuration in the third embodiment.

  FIG. 18 is a graph showing a result of measuring the cutoff region due to the difference in the dielectric constant of the dielectric substrate 2 as the S11 characteristic for the antenna 1c having the configuration in the third embodiment. In FIG. 18, the antenna 1c configured with a dielectric substrate having a relative permittivity εr = 15 is indicated by a solid line, the antenna 1c configured by a dielectric substrate having a relative permittivity εr = 12 is indicated by a broken line, and the relative permittivity εr = 8 shows an antenna 1c formed of a dielectric substrate by a one-dot chain line. From FIG. 18, when the relative dielectric constant of the dielectric substrate is lowered (when the relative dielectric constant εr = 8), when performing UWB communication in the low band (3.1 GHz to 4.9 GHz), the band of 5.0 GHz or higher It turns out that cannot be cut off accurately.

  Therefore, the inventors of the present application perform UWB communication in the low band (3.1 GHz to 4.9 GHz) even when the dielectric substrate 2 made of a general-purpose material (εr = about 4) is used. The antenna 1d capable of excellent communication was examined. In the antenna of the configuration of the third embodiment, the cutoff region in the case where a general-purpose material (εr = about 4) is used for the dielectric substrate 2 is measured as the S11 characteristic, and the measurement result is shown in FIG. . As shown in FIG. 19, in the configuration of the third embodiment, in the antenna provided with the dielectric substrate 2 made of a general-purpose material (εr = about 4), the S11 characteristic is −10 dB or more in the band of 5 to 7 GHz. However, reflection is not completely performed at the antenna input end, that is, it cannot be said that this band is completely blocked. In addition, in the band of 7 to 7.5 GHz, it can be seen that the S11 characteristic is −10 dB or less, that is, a pass band. With an antenna having such S11 characteristics, it becomes impossible to obtain the S11 characteristics (3.1 GHz to 4.9 GHz are the pass band, otherwise the cut-off band) necessary for low-band communication.

  FIG. 20 shows the configuration of antenna 1d in the present embodiment. FIG. 20 is a perspective view showing a configuration of the antenna 1d in the present embodiment, and a part thereof is a perspective view.

  As shown in FIG. 20, the antenna 1d includes a resin layer (dielectric layer) 7 in addition to the configuration of the third embodiment. As in the third embodiment, the antenna 1d is configured such that the second conductor 3 and the first conductor 4 are on the same plane on the dielectric substrate 2, and the second conductor 3 is further connected to the antenna 1d. A resin layer 7 is disposed so as to cover the surface.

  The dielectric substrate 2 is made of FR4 (relative permittivity εr = 4.7) which is a general-purpose material. Thus, unlike the third embodiment, by using such a general-purpose material, it is possible to reduce the cost of the antenna as compared with the third embodiment.

  The resin layer 7 is made of a high dielectric constant material having a relative dielectric constant εr = 15.

  The S11 characteristic in the antenna 1d of the present embodiment having the above configuration is measured. The measurement results are shown in the graph of FIG.

  From FIG. 21, it can be seen that the antenna 1d of the present embodiment has a characteristic equivalent to the S11 characteristic shown in FIG. 11 in the third embodiment.

  Thereby, even when the general-purpose material as described above is used as the dielectric substrate 2, the antenna 1d capable of performing good communication when performing UWB communication in a low band (3.1 GHz to 4.9 GHz). Can be provided.

  Further, with this configuration, the same wavelength shortening effect as that obtained in the dielectric substrate made of a material having a high relative dielectric constant in the first to third embodiments can be obtained. Therefore, an antenna having a relatively small size as shown in FIG. 7 can be provided.

  Furthermore, since other circuits are also generally used materials (for example, FR4), they and the antenna in this embodiment can be formed on the same substrate.

  The resin layer 7 may be disposed so as to cover at least the second conductor 3. If the resin layer 7 is disposed only on the second conductor 3 portion, the amount of the resin layer 7 used can be suppressed, and the cost can be reduced.

  Examples of the resin layer 7 include polyethersulfone (PPS), liquid crystal polymer (LCP), syndiotactic polystyrene (SPS), polycarbonate (PC), polyethylene terephthalate (PET), epoxy resin (EP), and polyimide resin. (PI), polyetherimide resin (PEI), phenol resin (PF), and the like can be used, but PPS or LCP is particularly preferable because it can have a high dielectric constant among the resins.

  Also in the present embodiment, the shape of the notches 6a to 6c is not limited to a circle as in the third embodiment, and FIG. 15 (a), FIG. 16 (a), and FIG. The shape as shown in FIG.

  Further, by making the second conductor 3 ″ circular, it is possible to realize a wide band of the antenna 1c as in the first to third embodiments. As described in the second embodiment, the present embodiment is implemented. The shape of the second conductor 3 ″ in the form of can also be the shape shown in FIGS.

  Further, the shape of the first conductor 4 of the present embodiment is not limited as in the second embodiment. For example, the first conductor 4 having the shapes as shown in FIGS. There may be.

  In addition, this Embodiment and the said Embodiment 1-3 can be manufactured by the manufacturing process including the etching process etc. which were demonstrated in the said Embodiment 1, and a 1st conductor and a 2nd conductor are previously prepared. It is also possible to manufacture it by forming it and integrally forming it together with a resin to be a dielectric substrate.

  Further, in the present embodiment and the first to third embodiments, the resin constituting the dielectric substrate 2 is not limited to one type, and may be composed of a plurality of types of resins. The relative dielectric constants of these resins may be the same or different.

[Embodiment 5]
Another embodiment of the antenna according to the present invention will be described below with reference to FIGS. In the present embodiment, the difference between the third and fourth embodiments will be described. For convenience of explanation, members having the same functions as those described in the third embodiment are denoted by the same reference numerals. The description is omitted.

  In the third embodiment, a material having a high dielectric constant such as a relative dielectric constant εr = 15 is used as the dielectric substrate 2. However, such a high dielectric constant material is not general-purpose. Therefore, if a general-purpose material having a relative dielectric constant not so high is used, further cost reduction can be realized.

  Here, in the fourth embodiment, as shown in FIG. 20, the second conductor 3 ″ and the first conductor 4 are configured to be on the same plane on the dielectric substrate 2. A resin layer 7 is disposed so as to cover the two conductors 3 ″. With this configuration, a non-generic high dielectric constant material is used only for the resin layer 7 covering the second conductor 3 ″, so that the amount used can be reduced and the cost can be reduced.

  Therefore, the antenna 1e in the present embodiment will be described in another form in which the usage amount of a material having a high dielectric constant that is not versatile is suppressed.

  FIG. 22 is a perspective view showing a configuration of the antenna 1e in the present embodiment, and a part thereof is a perspective view.

  As shown in FIG. 22, the antenna 1e includes an L-shaped dielectric substrate 2 ', and includes a resin substrate 9 in the same layer as the dielectric substrate 2'. That is, the surfaces of the dielectric substrate 2 ′ and the resin substrate 9 are flush with each other. Here, “the surfaces are flush with each other” includes not only the case where they are completely flush, but also the case where they are substantially flush. In the antenna 1e, the second conductor 3 ″ is provided on the surface of the resin substrate 9, and the second conductor 3 and the first conductor 4 provided on the dielectric substrate 2 ′ are in the same plane. It is comprised so that it may become.

  The dielectric substrate 2 ′ is made of FR4 (relative permittivity εr = 4.7) which is a general-purpose material. Thus, unlike the third embodiment, by using such a general-purpose material, it is possible to reduce the cost of the antenna as compared with the third embodiment.

  The resin substrate 9 is made of a high dielectric constant material having a relative dielectric constant εr = 15.

  The antenna 1e of the present embodiment having the above-described configuration can be manufactured with the dielectric substrate 2 'and the resin substrate 9 as separate bodies. Specifically, as shown in FIG. 23, the antenna 1e includes a dielectric substrate 2 ′ on which the first conductor 4 is formed and a resin substrate 9 on which the second conductor 3 ″ is formed from independent structures. 23, the power supply terminal 3 ″ a of the second conductor 3 ″ is disposed outside the resin substrate 9. Therefore, the dielectric substrate 2 on which the first conductor 4 is formed. 22 and the resin substrate 9 on which the second conductor 3 ″ is formed, respectively, and the power supply terminal 3 ″ a is connected to the power supply terminal region 5 provided on the dielectric substrate 2 ′ as shown in FIG. Thus, the antenna 1e of this embodiment can be manufactured, for example, when the notches 6a 'to 6c' and 6a "to 6c" shown in Fig. 15 (a) and Fig. 16 (a) are provided. Even in the production line, the second conductor 3 ″ and the resin substrate 9 are manufactured. It is possible only dealt with changing the lines, it is possible to efficiently produce an antenna having various shapes.

  The S11 characteristic of the antenna 1e of the present embodiment having the above configuration is measured. The measurement results are shown in the graph of FIG.

  From FIG. 24, it can be seen that the antenna 1e of the present embodiment has a characteristic equivalent to the S11 characteristic shown in FIG. 11 in the third embodiment.

  Thereby, even if it is the structure of this embodiment, the antenna which can perform favorable communication can be provided when performing UWB communication in a low band (3.1 GHz-4.9 GHz).

[Embodiment 6]
Another embodiment of the antenna according to the present invention will be described below with reference to FIGS. In the present embodiment, the difference between the third and fourth embodiments will be described. For convenience of explanation, members having the same functions as those described in the fourth embodiment are denoted by the same reference numerals. The description is omitted.

  In the fourth embodiment, as shown in FIG. 20, the second conductor 3 and the first conductor 4 are configured to be on the same plane on the dielectric substrate 2. A resin layer 7 is disposed so as to cover the surface. On the other hand, in the antenna 1 f in the present embodiment, the laminated substrate 10 is laminated on the dielectric substrate 2, and the second conductor 3 is formed on the laminated substrate 10. That is, the 2nd conductor 3 and the 1st conductor 4 are arrange | positioned so that each surface may become mutually parallel. Here, “each surface is parallel to each other” means “substantially parallel” that deviates from the state of being completely parallel in manufacturing in addition to the case where each surface is completely parallel. Is also included.

  FIG. 25 is a perspective view showing a configuration of the antenna 1f in the present embodiment, and a part thereof is a perspective view.

  The laminated substrate 10 is provided on the dielectric substrate 2 so as to be sandwiched between the second conductor 3 and the dielectric substrate 2 as shown in FIG. The laminated substrate 10 is made of a high dielectric constant material having a relative dielectric constant εr = 15. The magnitude | size (surface area) of the laminated substrate 10 should just be a magnitude | size by which the 2nd conductor 3 is arrange | positioned at the surface of the laminated substrate 10 at least.

  FIG. 26 shows a state where the configuration of the antenna 1f is disassembled. FIG. 26 is a perspective view showing configurations of the second conductor 3 and the laminated substrate 10, and a part thereof is a perspective view. As shown in FIG. 26, the power supply terminal 3 ″ b of the second conductor 3 is disposed outside the multilayer substrate 10. Accordingly, the dielectric substrate 2 ′ on which the first conductor 4 is formed, and the second conductor The antenna 1f can be manufactured by manufacturing the laminated substrate 10 on which 3 ″ is formed and connecting the feeding terminal 3 ″ b to the feeding terminal region 5 provided on the dielectric substrate 2. Thus, for example, even when the notches 6a ′ to 6c ′ and 6a ″ to 6c ″ shown in FIGS. 15A and 16A are provided, the second conductor 3 ″ in the production line is provided. In addition, since it is possible to cope with the problem by simply changing the line for manufacturing the laminated substrate 10, it is possible to efficiently manufacture antennas having various shapes.

  The dielectric substrate 2 is made of FR4 (relative permittivity εr = 4.7) which is a general-purpose material. Thus, unlike the third embodiment, by using such a general-purpose material, it is possible to reduce the cost of the antenna as compared with the third embodiment.

  As described above, the antenna 1f according to the present embodiment uses a high dielectric constant material only in a limited area of the laminated substrate 10, and thus realizes cost reduction of the antenna as compared with the third embodiment. be able to.

  The S11 characteristic of the antenna 1f of the present embodiment having the above configuration is measured. The measurement results are shown in the graph of FIG.

  From FIG. 27, it can be seen that the antenna 1f of the present embodiment has a characteristic equivalent to the S11 characteristic shown in FIG. 11 in the third embodiment.

  Thereby, even if it is the structure of this embodiment, the antenna which can perform favorable communication can be provided when performing UWB communication in a low band (3.1 GHz-4.9 GHz).

  In addition, the thickness of the laminated substrate 10 is a range in which the S11 characteristic is −10 dB or less in the 3.0 to 5.0 GHz band when the antenna 1f performs UWB communication in the low band (3.1 GHz to 4.9 GHz). Can be set as appropriate. For example, the outer shape of the antenna 1f (dielectric substrate 2) is 20 mm × 30 mm × thickness 1 mm, the diameter of the second conductor 3 ″ is 10 mm, and the center of the second conductor 3 ″ is from the 20 mm side of the antenna 1f. When it is configured to be disposed at about 5 mm, the S11 characteristic can be set to −10 dB or less by setting the thickness of the laminated substrate 10 to 0.5 to 2.0 mm.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims, and obtained by appropriately combining technical means disclosed in different embodiments. Such embodiments are also included in the technical scope of the present invention.

The antenna according to the present invention can block a wide band by configuring the radiation conductor and the rectangular conductor on the same plane. Therefore, avoiding the band already used in the 5.0 GHz wireless LAN, the band of 3.1 GHz to 4.9 GHz (Low Band), or 5.8 GHz to 10.6 GHz (High Band) ), The band other than the intended band can be accurately cut off. Furthermore, it is possible to provide an antenna having good directivity and realizing good communication quality. Therefore, for example, information terminals such as mobile phones and PDAs, PC card type radios, CF (compact flash (registered) (Trademark)) type radio equipment, IEEE 1394 type radio equipment and the like, and can be widely applied.

It is the perspective view which showed the structure of the antenna in embodiment which concerns on this invention. FIG. 2 is a cross-sectional view taken along the line AA ′ of the antenna shown in FIG. 1. It is the figure which analyzed about the directivity of the antenna shown in FIG. 1, (a) is the perspective view which showed typically the three-dimensional direction provided in the antenna in performing a radiation characteristic analysis, (b) is ( It is the figure which showed the analysis result of the radiation characteristic analysis of the antenna based on the three-dimensional direction shown in a). It is the perspective view which showed the structure of the antenna in other embodiment which concerns on this invention. FIG. 5 is a diagram in which the directivity of the antenna shown in FIG. 4 is analyzed, (a) is a perspective view schematically showing a three-dimensional direction provided in the antenna in performing the radiation characteristic analysis, and (b) is a diagram (a). It is the figure which showed the analysis result of the radiation characteristic analysis of the antenna based on the three-dimensional direction shown in FIG. It is the figure which showed the modification of an antenna, (a) is the perspective view which showed typically the three-dimensional direction provided in the said antenna in performing a radiation characteristic analysis, (b) was shown in (a). It is the figure which showed the analysis result of the radiation characteristic analysis of the antenna based on a three-dimensional direction. It is the perspective view which showed an example of the size of the antenna shown in FIG. (A)-(o) is the perspective view which showed the modification of the radiation conductor provided in the antenna shown in FIG. (A)-(i) is the perspective view which showed the modification of the rectangular conductor provided in the antenna shown in FIG. It is the perspective view which showed the structure of the antenna in other embodiment which concerns on this invention. It is a graph which shows the result measured about the S11 characteristic of the antenna shown in FIG. It is the figure which analyzed the characteristic of the notch part of the antenna shown in FIG. 10, (a) is the perspective view which showed arrangement | positioning of a notch part, (b) is the S11 characteristic of the antenna shown in (a). It is the graph which showed the result measured about. It is the figure which analyzed the characteristic of the notch part of the antenna shown in FIG. 10, (a) is the perspective view which showed arrangement | positioning of a notch part, (b) is S11 of the antenna shown in (a). It is the graph which showed the result measured about the characteristic. It is the figure which analyzed the characteristic of the notch part of the antenna shown in FIG. 10, (a) is the perspective view which showed arrangement | positioning of a notch part, (b) is the S11 characteristic of the antenna shown in (a). It is the graph which showed the result measured about. (A) is the perspective view which showed the modification of the notch part of the antenna shown in FIG. 10, (b) is the graph which showed the result measured about the S11 characteristic of the antenna shown in (a). (A) is the perspective view which showed the modification of the notch part of the antenna shown in FIG. 10, (b) is the graph which showed the result measured about the S11 characteristic of the antenna shown in (a). (A) And (b) is the perspective view which showed the modification of the notch part of the antenna shown in FIG. 11 is a graph showing the results of measuring the respective S11 characteristics when the dielectric substrate has different dielectric constants in the antenna shown in FIG. FIG. 11 is a graph showing a result of measuring S11 characteristics when a general-purpose material is used for the dielectric substrate in the antenna shown in FIG. 10. It is the perspective view which showed the structure of the antenna in other embodiment which concerns on this invention. It is a graph which shows the result of having measured the S11 characteristic of the antenna shown in FIG. It is the perspective view which showed the structure of the antenna in other embodiment which concerns on this invention. It is the perspective view which decomposed | disassembled the structure of the antenna shown in FIG. It is a graph which shows the result of having measured the S11 characteristic of the antenna shown in FIG. It is the perspective view which showed the structure of the antenna in other embodiment which concerns on this invention. It is the perspective view which decomposed | disassembled the structure of the antenna shown in FIG. It is a graph which shows the result of having measured the S11 characteristic of the antenna shown in FIG. It is a perspective view which shows the structure of the conventional broadband antenna apparatus. It is the figure which analyzed about the directivity of the conventional broadband antenna apparatus, (a) is the perspective view which showed typically the three-dimensional direction provided in the broadband antenna apparatus in performing radiation characteristic analysis, (b), It is the figure which showed the analysis result of the radiation characteristic analysis of the wideband antenna apparatus based on the three-dimensional direction shown in (a).

Explanation of symbols

1a to 1f1 antenna 2, 2 ′ dielectric substrate 3, 3 ″ second conductor 3 ″ a, 3 ″ b feeding terminal 4 first conductor 5 feeding terminal region (feeding portion)
6a-6c, 6a'-6c ', 6a "-6c" Notch 7 Resin layer (dielectric layer)
9 Resin substrate 10 Multilayer substrate

Claims (11)

  A first conductor and a second conductor having different shapes, and a power feeding section that feeds power to the first conductor and the second conductor, and the surfaces of the first conductor and the second conductor are parallel to each other. An antenna characterized by being arranged as follows.   2. The antenna according to claim 1, wherein the first conductor and the second conductor are configured to be flush with each other via the power feeding portion. The first conductor and the second conductor are formed on a substrate,
The antenna according to claim 1 or 2, wherein a dielectric layer made of a dielectric material having a dielectric constant higher than that of the substrate is provided so as to cover at least the second conductor. The first conductor is formed on the surface of the first substrate,
The second conductor is formed on a surface of a second substrate made of a dielectric material having a dielectric constant higher than that of the first substrate, which is configured to be flush with the surface of the first substrate. The antenna according to claim 1, wherein the antenna is provided. The first conductor is formed on the surface of the first substrate,
The second conductor has a smaller area than the first conductor and is formed on the surface of the second substrate having a smaller area than the first substrate.
The second substrate is made of a dielectric material having a dielectric constant higher than that of the first substrate, which is laminated on the surface of the first substrate where the first conductor is not formed. The antenna according to claim 1. The first conductor has a rectangular shape in which one of two adjacent sides is longer than the other side;
The antenna according to any one of claims 1 to 5, wherein the feeding portion is provided on one long side of the first conductor. The second conductor has a smaller area than the first conductor,
The antenna according to any one of claims 1 to 6, wherein in the power feeding unit, the second conductor is provided in one end region on one long side of the first conductor.   The antenna according to any one of claims 1 to 7, wherein the second conductor has a circular shape.   The antenna according to any one of claims 1 to 8, wherein a cutout portion is provided in at least one of the first conductor and the second conductor.   The antenna according to claim 9, wherein the notch has a circular shape.   The antenna according to claim 9 or 10, wherein a plurality of the cutout portions having different areas are provided.

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