Antenna Device

Abstract

To provide an antenna device capable of implementing a circularly polarized wave in a small size.SOLUTION: An antenna device 1 comprises: a ground part 10 that contains a liner-shaped part 13 for connecting a first point 11 and a second point 12 along a first direction A, and is formed so as to ground a conductive part of a substrate 2 on one side of a second direction B; a power supply part 20 that is provided to a first range D1 containing the first point 11 from the first range D1, a second range D2, and a third range D3 which are obtained by dividing the liner-shaped part 13 in the ground part 10 into three ranges along the first direction A; and an element part 30 that is supplied from the power supply part 20, and is formed in the conductive part insulated from the ground part 10 in a state of being projected to the other side of the second direction B from the liner-shaped part 13 from the first range D1. The element part 30 includes: a first element part 31 projected to the other side of the second direction B from the first range D1; and a second element part 32 extended toward a direction of the second point 12 along the first direction A from the first element part 31.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an antenna device. [Background technology]

[0002] Conventionally, antenna devices are used for transmitting and receiving radio waves. Technologies relating to such antenna devices are described in, for example, Patent Documents 1 to 3, the sources of which are shown below.

[0003] Patent Document 1 discloses a circularly polarized composite monopole antenna. This circularly polarized composite monopole antenna has a ground plate formed of a plate-shaped conductor, and a feed element and a parasitic element formed by bending the ground plate into an inverted L shape are provided on the ground plate. The feed element and the parasitic element are provided so that the rising edge of the feed element and the rising edge of the parasitic element are inserted through a through hole provided in a dielectric on the ground plate and stand upright from the ground plate.

[0004] Patent Document 2 discloses a wideband circularly polarized antenna. This wideband circularly polarized antenna is configured by arranging a first antenna element and a second antenna element, both of which are trapezoidal, in point symmetry with respect to a power feeder.

[0005] Patent Document 3 discloses a monopole antenna. This monopole antenna is configured to include a circular disk-shaped coplanar waveguide transmission line. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2009-225068 A [Patent Document 2] JP 2016-116016 A [Patent Document 3] International Publication No. 2017 / 138800 Summary of the Invention [Problem to be solved by the invention]

[0007] The technology described in Patent Document 1 has a three-dimensional shape because the feed element and the parasitic element are configured in a state of standing from the ground plate via a dielectric. Therefore, it may not be possible to use it when there is a height limit in the area in which the antenna device is arranged. In addition, the technology described in Patent Document 2 is a so-called parallel type antenna device, so a pair of antenna elements is required. Therefore, the area occupied by the antenna device increases. Thus, the technologies described in Patent Documents 1 and 2 have room for improvement in terms of miniaturizing the antenna device.

[0008] In addition, although there are various types of polarized radio waves, such as horizontally polarized waves, vertically polarized waves, and circularly polarized waves, the technology described in Patent Document 3 is related to a monopole antenna and can therefore only be used for transmitting and receiving vertically polarized radio waves or horizontally polarized radio waves, and therefore cannot be used for transmitting and receiving circularly polarized radio waves.

[0009] Therefore, there is a demand for a small antenna device capable of circularly polarizing waves. [Means for solving the problem]

[0010] A characteristic configuration of the antenna device according to the present invention includes a ground section including a linear portion connecting a first point and a second point along a predetermined first direction parallel to a surface of the substrate, and formed by grounding a conductor portion of the substrate on one side of a second direction perpendicular to the first direction and parallel to the surface of the substrate; a power supply section provided in a first range including the first point among a first range, a second range, and a third range obtained by dividing the linear portion of the ground section into three equal parts along the first direction; and an element section fed by the power supply section, formed in a conductor portion of the substrate insulated from the ground section in a state where the element section protrudes from the first range to the other side in the second direction beyond the linear portion, and the element section has a first element section protruding from the first range to the other side in the second direction, and a second element section extending from the first element section along the first direction toward the second point.The ground portion has a protruding portion that protrudes from the second point side of the linear portion to the other side in the second direction by a predetermined width, and the second element portion extends from the first element portion toward the protruding portion. The point is to

[0011] With this characteristic configuration, the wire portion is adjusted in accordance with the phase of the power fed from the power feeding portion. In the ground portion, which is a conductor portion of the substrate and is provided on one side in the second direction, The charge distribution in the element part consisting of the other conductor part of the substrate is compared with the charge distribution in the element part consisting of the other conductor part of the substrate. and generating a difference between the charge distributions, and based on the difference in the charge distribution, It is possible to generate an electric field that rotates around an axis along a direction perpendicular to both of the second directions. Therefore, a small antenna device that can be used to transmit and receive circularly polarized radio waves can be constructed. It becomes possible. Furthermore, when there is a difference between the charge distribution in the ground section provided on one side of the second direction including the linear section and the charge distribution in the element section depending on the phase of the power supplied by the power supply section, an electric field can be generated between the ground section provided on one side of the second direction including the linear section and the element section. Furthermore, when there is a difference between the charge distribution in the protruding section and the charge distribution in the element section depending on the phase of the power supplied by the power supply section, an electric field can be generated between the protruding section and the element section. Therefore, it is possible to more easily transmit and receive circularly polarized radio waves with the direction perpendicular to both the first direction and the second direction as the axis.

[0012] Also, Another characteristic configuration of the antenna device according to the present invention includes a ground section including a linear portion connecting a first point and a second point along a predetermined first direction parallel to a surface of the substrate, and formed by grounding a conductor portion of the substrate on one side of a second direction perpendicular to the first direction and parallel to the surface of the substrate; a power supply section provided in a first range, which is obtained by dividing the linear portion of the ground section into three equal parts along the first direction, the first range including the first point, and an element section that is fed by the power supply section and is formed in a conductor portion of the substrate that is insulated from the ground section and protrudes from the first range to the other side in the second direction beyond the linear portion, and the element section has a first element section that protrudes from the first range to the other side in the second direction, and a second element section that extends from the first element section along the first direction toward the second point, The ground portion has a protruding portion that protrudes from the second point side of the linear portion to the other side in the second direction by a predetermined width, and the second element portion extends from the first element portion toward the protruding portion. The ground portion has a length in the second direction longer than a length in the first direction. be.

[0013] With this characteristic configuration, a difference can be generated between the charge distribution in the ground section made of a conductor part of the substrate and provided on one side of the second direction including the linear section and the charge distribution in the element section made of another conductor part of the substrate, depending on the phase of the power supplied by the power supply section, and an electric field can be generated that rotates about an axis that is perpendicular to both the first direction and the second direction parallel to the surface of the substrate, based on the difference in charge distribution. Therefore, it is possible to configure a small antenna device that can be used to transmit and receive circularly polarized radio waves. Furthermore, when there is a difference between the charge distribution in the ground section provided on one side of the second direction including the linear section and the charge distribution in the element section depending on the phase of the power supplied by the power supply section, an electric field can be generated between the ground section provided on one side of the second direction including the linear section and the element section. Furthermore, when there is a difference between the charge distribution in the protruding section and the charge distribution in the element section depending on the phase of the power supplied by the power supply section, an electric field can be generated between the protruding section and the element section. Therefore, it is possible to more easily transmit and receive circularly polarized radio waves with the direction perpendicular to both the first direction and the second direction as the axis. Furthermore, it is possible to easily generate a difference between the charge distribution in the ground portion provided on one side of the second direction including the linear portion and the charge distribution in the protruding portion according to the phase of the power supplied by the power supply portion. Therefore, it is possible to generate an electric field between the ground portion provided on one side of the second direction including the linear portion and the element portion, and between the protruding portion and the element portion according to the phase of the power supplied by the power supply portion, and to more easily transmit and receive circularly polarized radio waves with the direction perpendicular to both the first direction and the second direction as the axis.

[0014] Also, Another characteristic configuration of the antenna device according to the present invention is a ground section including a linear portion connecting a first point and a second point along a predetermined first direction parallel to a surface of the substrate, and formed by grounding a conductor portion of the substrate on one side of a second direction perpendicular to the first direction and parallel to the surface of the substrate; a power supply section provided in a first range including the first point among a first range, a second range, and a third range obtained by dividing the linear portion of the ground section into three equal parts along the first direction; and an element section that is fed by the power supply section and is formed in a conductor portion of the substrate that is insulated from the ground section while protruding from the first range to the other side in the second direction beyond the linear portion, the element section having a first element section protruding from the first range to the other side in the second direction, and a second element section extending from the first element section along the first direction toward the second point, the second element section being formed so as to be gradually separated from the linear portion as it approaches the second point from the first element section. be.

[0015] With this characteristic configuration, a difference can be generated between the charge distribution in the ground section made of a conductor part of the substrate and provided on one side of the second direction including the linear section and the charge distribution in the element section made of another conductor part of the substrate, depending on the phase of the power supplied by the power supply section, and an electric field can be generated that rotates about an axis that is perpendicular to both the first direction and the second direction parallel to the surface of the substrate, based on the difference in charge distribution. Therefore, it is possible to configure a small antenna device that can be used to transmit and receive circularly polarized radio waves. In addition, the effect of the charge distribution in the ground portion provided on one side in the second direction including the linear portion on the charge distribution in the element portion can be reduced, making it easier to generate an electric field between the ground portion provided on one side in the second direction including the linear portion and the element portion.

[0016] Also, Another characteristic configuration of the antenna device according to the present invention includes a ground section including a linear portion connecting a first point and a second point along a predetermined first direction parallel to a surface of the substrate, and formed by grounding a conductor portion of the substrate on one side of a second direction perpendicular to the first direction and parallel to the surface of the substrate; a power supply section provided in a first range that includes the first point, among a first range, a second range, and a third range that divide the linear portion of the ground section into three equal parts along the first direction; and a power supply section provided in the first range that includes the first point, the power supply section being fed from the power supply section and protruding from the first range to the other side in the second direction beyond the linear portion. and an element portion formed in an insulated conductor portion, the element portion having a first element portion protruding from the first range to the other side in the second direction, and a second element portion extending from the first element portion along the first direction toward the second point, the second element portion being formed so as to be gradually spaced apart from the linear portion as it approaches the second point from the first element portion, and having a reduced width portion whose width in a direction perpendicular to the extension direction extending from the first element portion gradually narrows as it approaches the second point from the first element portion. be.

[0017] With this characteristic configuration, a difference can be generated between the charge distribution in the ground section made of a conductor part of the substrate and provided on one side of the second direction including the linear section and the charge distribution in the element section made of another conductor part of the substrate, depending on the phase of the power supplied by the power supply section, and an electric field can be generated that rotates about an axis that is perpendicular to both the first direction and the second direction parallel to the surface of the substrate, based on the difference in charge distribution. Therefore, it is possible to configure a small antenna device that can be used to transmit and receive circularly polarized radio waves. In addition, the effect of the charge distribution in the ground portion provided on one side in the second direction including the linear portion on the charge distribution in the element portion can be reduced, making it easier to generate an electric field between the ground portion provided on one side in the second direction including the linear portion and the element portion. Furthermore, it is possible to more easily reduce the influence of the charge distribution in the ground section provided on one side in the second direction including the linear section on the charge distribution in the element section. Also, it is possible to provide variation in the antenna length formed between the power feed point in the element section where power is fed by the power feed section and the tip section in the second element section that is closest to the second point. Therefore, it is possible to widen the band of radio waves that can be transmitted and received.

[0018] Also, Another characteristic configuration of the antenna device according to the present invention includes a ground section including a linear portion connecting a first point and a second point along a predetermined first direction parallel to a surface of the substrate, the ground section being formed by grounding a conductor portion of the substrate on one side of a second direction perpendicular to the first direction and parallel to the surface of the substrate; a power supply section provided in a first range, which includes the first point, among a first range, a second range, and a third range obtained by dividing the linear portion of the ground section into three equal parts along the first direction; and an element section, which is supplied with power from the power supply section and is formed in a conductor portion of the substrate that is insulated from the ground section, in a state where the element section protrudes from the first range to the other side in the second direction beyond the linear portion; the element portion has a first element portion protruding from the first range to the other side in the second direction, and a second element portion extending from the first element portion along the first direction toward the second point, the second element portion being formed so as to be gradually separated from the linear portion as it approaches the second point from the first element portion, and having a reduced width portion whose width in a direction perpendicular to the extension direction from the first element portion gradually narrows as it approaches the second point from the first element portion, and further having a constant width portion which is provided on the second point side of the reduced width portion and is electrically connected to the reduced width portion, and has a constant width. be.

[0019] With this characteristic configuration, a difference can be generated between the charge distribution in the ground section made of a conductor part of the substrate and provided on one side of the second direction including the linear section and the charge distribution in the element section made of another conductor part of the substrate, depending on the phase of the power supplied by the power supply section, and an electric field can be generated that rotates about an axis that is perpendicular to both the first direction and the second direction parallel to the surface of the substrate, based on the difference in charge distribution. Therefore, it is possible to configure a small antenna device that can be used to transmit and receive circularly polarized radio waves. In addition, the effect of the charge distribution in the ground portion provided on one side in the second direction including the linear portion on the charge distribution in the element portion can be reduced, making it easier to generate an electric field between the ground portion provided on one side in the second direction including the linear portion and the element portion. Furthermore, it is possible to more easily reduce the influence of the charge distribution in the ground section provided on one side in the second direction including the linear section on the charge distribution in the element section. Also, it is possible to provide variation in the antenna length formed between the power feed point in the element section where power is fed by the power feed section and the tip section in the second element section that is closest to the second point. Therefore, it is possible to widen the band of radio waves that can be transmitted and received. It is also possible to provide variation in the length of the antenna formed between the feeding point in the element section, where power is fed by the feeding section, and the tip section in the second element section that is closest to the second point.

[0020] The length of the ground portion along the second direction may be equal to or less than half of the length of the ground portion along the first direction.

[0021] Even with this configuration, a difference can be generated between the charge distribution in the ground section provided on one side in the second direction including the linear section and the charge distribution in the element section based on the power supply from the power supply section, and an electric field can be generated between the ground section provided on one side in the second direction including the linear section and the element section. Therefore, it is possible to further miniaturize the antenna device capable of transmitting and receiving circularly polarized radio waves.

[0022] It is also preferable that the second element portion is formed so as to be gradually spaced apart from the linear portion as it approaches the second point from the first element portion.

[0023] With this configuration, it is possible to reduce the effect of the charge distribution in the ground section provided on one side in the second direction including the linear section on the charge distribution in the element section, thereby making it easier to generate an electric field between the ground section provided on one side in the second direction including the linear section and the element section.

[0024] It is also preferable that the second element portion has a quadrangular shape in a plan view.

[0025] With this configuration, the element portion can be easily processed. [Brief description of the drawings]

[0026] [Figure 1] FIG. 2 is a plan view of a substrate on which the antenna device is provided. [Diagram 2] FIG. 2 is an enlarged view of the antenna device. [Diagram 3] FIG. 4 is a diagram showing the charge distribution of the antenna device. [Figure 4] 1A and 1B are diagrams illustrating radio waves radiated by an antenna device. [Diagram 5] This is the VSWR data for the antenna device. [Figure 6] FIG. 11 is a plan view of an antenna device according to another embodiment. [Figure 7] FIG. 11 is a plan view of an antenna device according to another embodiment. [Figure 8] 13A and 13B are diagrams illustrating radio waves radiated by an antenna device according to another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] The antenna device according to the present invention is configured to be capable of transmitting and receiving circularly polarized radio waves. An antenna device 1 according to the present embodiment will be described below.

[0028] The antenna device 1 is provided on a substrate 2. FIG. 1 shows a plan view of the substrate 2. FIG. 2 shows an enlarged view of the vicinity of the power supply unit 20. In the following description, a predetermined direction parallel to the surface of the substrate 2 is defined as a first direction A, and a direction perpendicular to the first direction A and parallel to the surface of the substrate 2 is defined as a second direction B. In this embodiment, the substrate 2 is formed in a rectangular shape with chamfered corners. In this embodiment, the first direction A is a direction along the direction in which the short side of the rectangular substrate 2 extends (hereinafter referred to as the "short direction"), and the second direction B is a direction along the direction in which the long side of the rectangular substrate 2 extends (hereinafter referred to as the "longitudinal direction"). If the wavelength corresponding to the highest frequency among the frequency bands used in the antenna device 1 is λ, in this embodiment, the substrate 2 is configured to have a length of 0.48λ along the first direction A and a length of 2.3λ ​​along the second direction B of the substrate 2.

[0029] As shown in FIG. 1, the antenna device 1 includes a ground section 10, a power supply section 20, and an element section 30.

[0030] 2, the ground portion 10 includes a linear portion 13 connecting a first point 11 and a second point 12 along the first direction A, and is formed by grounding a conductor portion of the substrate 2 on one side in the second direction B. The linear portion 13 connecting the first point 11 and the second point 12 along the first direction A means that the linear portion 13 is parallel to the first direction A, and the first point 11 and the second point 12 are on the linear portion 13. In this embodiment, the first point 11 is set at a position spaced apart from an outer edge portion 2A on one side of the substrate 2 in the first direction A toward the center of the substrate 2 along the first direction A, and the second point 12 is set at a position spaced apart from an outer edge portion 2B on the other side of the substrate 2 in the first direction A toward the center of the substrate 2 along the first direction A. Therefore, the first point 11 and the second point 12 are set at positions inward from the outer edge 2A and the outer edge 2B, respectively, toward the center of the substrate 2 along the first direction A. The linear portion 13 corresponds to a line virtually connecting the first point 11 and the second point 12. Note that the first point 11 and the second point 12 are not provided as points actually drawn on the substrate 2, but are defined to make the linear portion 13 easier to understand.

[0031] One side in the second direction B is one of the two longitudinal end portions of the substrate 2. That is, in the example of Fig. 1, it is one of the outer edge portions 2C and 2D of the substrate 2. In this embodiment, one side in the second direction B is the outer edge portion 2D side of the outer edge portions 2C and 2D of the substrate 2.

[0032] Here, the substrate 2 is formed by laminating a conductor and a dielectric. The conductor portion of the substrate 2 corresponds to a conductor that is laminated with such a dielectric to constitute the substrate 2. The ground portion 10 is formed by patterning such a conductor portion of the substrate 2 to include a linear portion 13 that virtually connects a first point 11 set at a position spaced from an outer edge portion 2A on one side of the substrate 2 in the first direction A toward the center of the substrate 2 along the first direction A, and a second point 12 set at a position spaced from an outer edge portion 2B on the other side of the substrate 2 in the first direction A toward the center of the substrate 2 along the first direction A, and is grounded.

[0033] In this embodiment, the ground portion 10 has a protruding portion 17 that protrudes by a predetermined width from the second point 12 side of the linear portion 13 to the other side in the second direction B. The second point 12 side of the linear portion 13 means a side of the linear portion 13 closer to the second point 12 than the center between the first point 11 and the second point 12.

[0034] Here, as described above, the linear portion 13 is provided between the first point 11 and the second point 12, and the linear portion 13 is divided into three equal parts along the first direction A, and the three equal parts are defined as a first range D1, a second range D2, and a third range D3. In this case, two points are required between the first point 11 and the second point 12. If the point closer to the first point 11 of the two points is defined as the first auxiliary point 14, and the point closer to the second point 12 is defined as the second auxiliary point 15, then the area between the first point 11 and the first auxiliary point 14 in the linear portion 13 corresponds to the first range D1. Furthermore, the area between the first auxiliary point 14 and the second auxiliary point 15 in the linear portion 13 corresponds to the second range D2, and the area between the second auxiliary point 15 and the second point 12 in the linear portion 13 corresponds to the third range D3.

[0035] In this embodiment, a protrusion 17 is provided in a third range D3 between the second auxiliary point 15 and the second point 12, protruding to the other side in the second direction B with a predetermined width. The predetermined width is a width set according to the frequency of the radio waves transmitted and received by the antenna device 1. The other side in the second direction B is the outer edge 2C side when viewed from the linear part 13 along the first direction A. Therefore, the ground part 10 has a protrusion 17 that protrudes from the third range D3 between the second auxiliary point 15 and the second point 12 to the outer edge 2C side when viewed from the linear part 13 along the first direction A with a width set according to the frequency of the radio waves transmitted and received by the antenna device 1. In this embodiment, the protrusion 17 is configured in a rectangular shape with a side along the first direction A as the short side and a side along the second direction B as the long side. In addition, a corner of the shape of the protrusion 17 on the outer edge 2B side and on the outer edge 2D side is provided so as to coincide with the second point 12. Such a protrusion 17, like the ground section 10, is formed by patterning a conductor portion of the substrate 2, and is composed of a conductor that has the same DC potential as the portion of the ground section 10 that is formed on one side of the linear section 13 in the second direction B.

[0036] As shown in FIG. 1, in this embodiment, the ground section 10 is configured such that the length along the second direction B is longer than the length along the first direction A. The length along the second direction B is the length of the ground section 10 along the second direction B, and in this embodiment, it is the length L1 from the linear portion 13 to the end of the ground section 10 on the outer edge 2D side. The length along the first direction A is the length of the ground section 10 along the first direction A, and in this embodiment, it is the length L2 from the end of the ground section 10 on the outer edge 2A side to the end of the ground section 10 on the outer edge 2B side. In FIG. 1, the ground section 10 is formed so that the length of the linear portion 13 along the first direction A is shorter than the length L2, but the length of the linear portion 13 along the first direction A may be formed to be the length L2.

[0037] In this embodiment, the distance between the first point 11 and the second point 12 is 0.33λ, the length of the protrusion 17 along the first direction A is 0.03λ, and the length of the protrusion 17 along the second direction B is 0.11λ.

[0038] The power supply unit 20 is provided in the first range D1 including the first point 11 among a first range D1, a second range D2, and a third range D3 obtained by dividing the linear portion 13 of the ground portion 10 into three equal parts along the first direction A. The first range D1 is between the first point 11 and a first auxiliary point 14 on the linear portion 13. The power supply unit 20 is provided in this first range D1. The power supply unit 20 supplies power to the above-mentioned ground portion 10 and an element portion 30 described later so that the antenna device 1 transmits and receives radio waves propagating through the air. Specifically, the power supply unit 20 applies (grounds) a reference potential (0V) to the ground portion 10 from a power supply point 21N and applies AC power of a predetermined frequency to the element portion 30 from a power supply point 21L. Therefore, power feeding section 20 is provided in first range D1 between first point 11 and first auxiliary point 14 in linear section 13, applies a reference potential (0 V) to ground section 10 (ground), and applies AC power of a predetermined frequency to element section 30. In this embodiment, power feeding point 21N and power feeding point 21L are provided at a position 0.06λ away from first point 11.

[0039] The element unit 30 is fed with power from the power feed unit 20, and is formed in a conductor portion insulated from the ground unit 10 in the substrate 2 in a state where it protrudes from the linear unit 13 to the other side in the second direction B in the first range D1. Being fed with power from the power feed unit 20 means that power is supplied from the power feed unit 20, as described above. The first range D1 is a range from the first point 11 to the first auxiliary point 14 in the linear unit 13. The state where it protrudes from the linear unit 13 to the other side in the second direction B means that it protrudes from the linear unit 13 on the opposite side to the ground unit 10 provided on the outer edge 2D side of the substrate 2 from the linear unit 13, which is one side of the second direction B from the linear unit 13, that is, on the outer edge 2C side of the substrate 2 from the linear unit 13. The conductor portion insulated from the ground unit 10 in the substrate 2 refers to a conductor portion formed by patterning so as to be separated from the ground unit 10 formed by patterning the conductor portion of the substrate 2 with a predetermined insulation distance. Therefore, power is supplied from the power supply section 20 to the power supply point 21L, and the element section 30 is formed in a conductor section that is patterned so as to be separated from the ground section 10, which is formed by patterning the conductor section of the substrate 2, with a predetermined insulation distance, in a state where the element section 30 protrudes further than the linear section 13 from the range from the first point 11 to the first auxiliary point 14 on the linear section 13 toward the outer edge section 2C of the substrate 2 than the linear section 13.

[0040] In this embodiment, the power supply point 21L through which power is supplied from the power supply unit 20 to the element unit 30 is provided on the linear unit 13, but the element unit 30 is configured to have a portion that protrudes from the power supply point 21L to one side in the second direction B. Therefore, the ground unit 10 is formed by cutting out so as to surround a portion of the element unit 30 that includes the power supply point 21L. That is, the ground unit 10 has a cutout portion 16 in the first range D1. Note that, in the element unit 30, the power supply point 21L through which power is supplied from the power supply unit 20 may be provided on the other side of the linear unit 13 in the second direction B, or may be provided on one side of the linear unit 13 in the second direction B.

[0041] The element portion 30 has a first element portion 31 and a second element portion 32. The first element portion 31 protrudes from a first range D1 to the other side in the second direction B. The first range D1 is a range between the first point 11 and the first auxiliary point 14 in the linear portion 13, and a power supply point 21L to which power is supplied from the power supply portion 20 in the element portion 30 is provided in this first range D1. The other side in the second direction B is the outer edge portion 2C side of the substrate 2 as viewed from the linear portion 13. Therefore, the first element portion 31 is provided with the power supply point 21L to which power is supplied from the power supply portion 20, and is provided so as to protrude from the first range D1, which is a range between the first point 11 and the first auxiliary point 14 in the linear portion 13, to the outer edge portion 2C side of the substrate 2 as viewed from the linear portion 13. In this embodiment, as shown in FIG. 2, the first element portion 31 has a width corresponding to the cutout portion 16 and is configured in a rectangular shape with the side along the first direction A as the short side and the side along the second direction B as the long side.

[0042] The second element part 32 extends from the first element part 31 along the first direction A toward the second point 12. As described above, the first element part 31 is provided so as to protrude from the first range D1 toward the outer edge part 2C side of the substrate 2 as viewed from the linear part 13. "Along the first direction A" means "so as to have a portion parallel to the linear part 13." "Toward the direction of the second point 12" means, as viewed from the first element part 31, toward the outer edge part 2B side of the substrate 2. Therefore, the second element part 32 is provided so as to extend from the first element part 31 provided so as to protrude from the first range D1 toward the outer edge part 2C side of the substrate 2 as viewed from the linear part 13 toward the outer edge part 2B side of the substrate 2 as viewed from the first element part 31, so as to have a portion parallel to the linear part 13. Therefore, the second element portion 32 is provided so as to extend from a portion 41 of the rectangular first element portion 31 along the second direction B on the outer edge portion 2B side.

[0043] In this embodiment, the ground portion 10 has a protrusion 17. In addition, as shown in Fig. 2, an outer edge 51 of the protrusion 17 on the outer edge 2C side is configured to be closer to the outer edge 2C of the substrate 2 in the second direction B than an outer edge 52 of the second element portion 32 on the outer edge 2C side. In this embodiment, the second element portion 32 extends from the first element portion 31 toward the protrusion 17.

[0044] Such first element portion 31 and second element portion 32 are formed by patterning one conductor portion. Therefore, first element portion 31 and second element portion 32 are composed of conductors that have the same direct current potential.

[0045] In this embodiment, the second element portion 32 is formed so as to gradually move away from the linear portion 13 as it approaches the second point 12 from the first element portion 31. In this embodiment, "as it approaches the second point 12 from the first element portion 31" means "as it approaches the protruding portion 17 from the first element portion 31." "Gradually moving away from the linear portion 13" means that the distance between the outer edge portion 33 and the linear portion 13 of the second element portion 32 on the linear portion 13 side gradually increases from the boundary portion 34 with the first element portion 31 along the first direction A to the closest portion 35 of the second element portion 32 that is closest to the protruding portion 17. Therefore, the second element portion 32 is formed such that as it approaches the protrusion 17 from the first element portion 31, the outer edge portion 33 on the linear portion 13 side of the second element portion 32 gradually becomes wider in distance between the outer edge portion 33 and the linear portion 13.

[0046] In this embodiment, the second element part 32 is formed in the shape of a right-angled triangle, and the right-angled corner of the second element part 32 coincides with the corner of the rectangular first element part 31 on the outer edge part 2B side and on the outer edge part 2C side, one of the two sides of the right-angled triangle sandwiching the corner coincides with the side (part 41) on the outer edge part 2B side of the first element part 31, and the other of the two sides of the right-angled triangle sandwiching the corner is parallel to the linear part 13. Therefore, the hypotenuse of the right-angled triangle (corresponding to the above-mentioned "outer edge part 33") is provided so as to face the linear part 13 side. This makes it possible to form the second element part 32 so that the interval between the outer edge part 33 and the linear part 13 gradually becomes wider as the second element part 32 approaches the protruding part 17 from the first element part 31, as described above.

[0047] In other words, the second element portion 32 has a reduced width portion 18 in which the width along the orthogonal direction perpendicular to the extension direction from the first element portion 31 gradually narrows as it approaches the second point 12 from the first element portion 31. The extension direction from the first element portion 31 is the first direction A. Therefore, the orthogonal direction perpendicular to the extension direction from the first element portion 31 corresponds to the second direction B perpendicular to the first direction A. Therefore, the second element portion 32 is configured such that the width along the second direction B gradually narrows as it approaches the second point 12 from the first element portion 31. Such a portion can also be referred to as a reduced width portion 18.

[0048] In this embodiment, the length of the element portion 30 along the first direction A is 0.17λ, and the length of the element portion 30 along the second direction B is 0.1λ. In addition, the distance X between the end portion (closest portion 35) of the reduced width portion 18 closest to the protrusion 17 and the linear portion 13 is preferably 0.04λ or more (preferably 0.06λ or more).

[0049] FIG. 3 shows the charge distribution generated between the ground section 10 and the element section 30 when power is supplied to the ground section 10 and the element section 30 in the antenna device 1 thus formed.

[0050] As described above, the power supply unit 20 grounds the ground unit 10 and supplies AC power to the element unit 30. FIG. 3A shows the charge distribution when the phase of the AC power is 60 degrees. In this case, the portion of the ground unit 10 opposite to the side where the element unit 30 protrudes from the linear unit 13 (referred to as the "ground main body 10A") is positively charged, and the protrusion 17 and the element unit 30 are negatively charged. In FIG. 3, the positively charged state is shown as "E+" and the negatively charged state is shown as "E-". Therefore, an electric field is generated between the ground main body 10A and the element unit 30 in the direction from the ground main body 10A to the element unit 30, as shown by the arrow C.

[0051] 3B shows the charge distribution when the phase of the AC power is 150 degrees. In this case, the protrusion 17 is positively charged, and the ground body 10A and the element 30 are negatively charged. As a result, an electric field is generated between the protrusion 17 and the element 30 in the direction from the protrusion 17 to the element 30, as shown by the arrow C.

[0052] 3C shows the charge distribution when the phase of the AC power is 240 degrees. In this case, the protrusion 17 and the element 30 are positively charged, and the gland body 10A is negatively charged. As a result, an electric field is generated between the gland body 10A and the element 30 in the direction from the element 30 to the gland body 10A, as shown by the arrow C.

[0053] 3D shows the charge distribution when the phase of the AC power is 330 degrees. In this case, the gland main body 10A and the element 30 are positively charged, and the protrusion 17 is negatively charged. As a result, an electric field is generated between the protrusion 17 and the element 30 in the direction from the element 30 to the protrusion 17, as shown by the arrow C.

[0054] By continuing to supply such AC power, it is possible to generate an electric field from the substrate 2 that rotates around an axis perpendicular to both the first direction A and the second direction B. Therefore, by providing the substrate 2 in an upright position, it is possible to transmit and receive radio waves by circular polarization as shown in FIG. 4A. In addition, when the present antenna device 1 is used as a receiving antenna device, it is possible to receive radio waves by vertical polarization as shown in FIG. 4B, and it is possible to receive radio waves by horizontal polarization as shown in FIG. 4C. In addition, when the present antenna device 1 is used as a transmitting antenna device, an antenna device capable of receiving only radio waves by vertical polarization as shown in FIG. 4B can receive radio waves transmitted from the antenna device 1, and an antenna device capable of receiving only radio waves by horizontal polarization as shown in FIG. 4C can receive radio waves transmitted from the antenna device 1.

[0055] Fig. 5 shows the VSWR characteristic of the present antenna device 1. In Fig. 5, the vertical axis represents the VSWR value, and the horizontal axis represents the frequency. In general, it is desirable for an antenna device to have a VSWR value of 3 or less. By configuring as described above, it is possible to realize the present antenna device 1 having a VSWR value of 3 or less over a wide frequency range, as shown in Fig. 5.

[0056] Other embodiments In the above embodiment, the element portion 30 has been described as being composed of the first element portion 31 having a rectangular shape in a plan view and the second element portion 32 having a right-angled triangular shape in a plan view. For example, as shown in Fig. 6(A), the first element portion 31 may be composed of a first portion 37 having a rectangular shape in a plan view and a second portion 38 having a triangular shape in a plan view. In this case, it is preferable to configure the first portion so that an edge portion 37A on the outer edge portion 2A side coincides with an edge portion 38A on the outer edge portion 2B side in the second portion.

[0057] Also, the second element portion 32 can be configured to have an elliptical shape with a central angle of 90 degrees in a plan view, as shown in Fig. 6(B). In this case, it is preferable that the arc-shaped portion is provided so as to face the linear portion 13. Furthermore, the convex arc-shaped portion in Fig. 6(B) can be configured to have a concave shape, as shown in Fig. 6(C).

[0058] Furthermore, the second element portion 32 may be configured to have a rectangular shape in plan view. In this case, as shown in Fig. 6(D), it is preferable to configure the first element portion 31 to extend from the outer edge portion 2C side of the substrate 2 along the first direction A toward the protruding portion 17. Also, as shown in Fig. 6(E), the length of the first element portion 31 along the second direction B may be approximately the same as above the linear portion 13, and the second element portion 32 may be configured to have a rectangular shape in plan view from there toward the protruding portion 17 side.

[0059] 6(F), the second element portion 32 may have a constant width portion 19, which is electrically connected to the reduced width portion 18 on the second point 12 side of the reduced width portion 18 and has a constant width. The reduced width portion 18 is a portion whose width along the second direction B gradually narrows as it approaches the second point 12 from the first element portion 31. The constant width portion 19, whose length along the second direction B is constant, may be provided on the opposite side of the reduced width portion 18 to the first element portion 31 along the first direction A, i.e., on the side closer to the protruding portion 17 along the first direction A.

[0060] In the above embodiment, the protrusion 17 is described as being provided so that the corner on the outer edge 2B side and the outer edge 2D side coincides with the second point 12. However, it is also possible to provide the corner of the protrusion 17 on the outer edge 2B side and the outer edge 2D side of the substrate 2 not coinciding with the second point 12. In this case, as shown in FIG. 6G, the corner of the protrusion 17 on the outer edge 2B side and the outer edge 2D side of the substrate 2 can be provided apart from the second point 12 to the first point 11 along the first direction A of the linear portion 13. However, it is preferable that the protrusion 17 is within the third range D3. Furthermore, as shown in FIG. 6H, the ground portion 10 can be configured so that the outer edge 2D side of the protrusion 17 has a portion 60 cut out along the width of the protrusion 17. Even in this case, it is preferable that the protrusion 17 is within the third range D3.

[0061] In the above embodiment, the ground section 10 has been described as being configured such that the length along the second direction B is longer than the length along the first direction A. However, as shown in Fig. 7, the length along the second direction B of the ground section 10 may be equal to or less than half the length along the first direction A. For example, if the wavelength corresponding to the highest frequency in the frequency band used by the antenna device 1 is λ, and the length T of the ground section 10 along the second direction B is 0.17λ, it is sufficient that the length S along the first direction A is 0.34λ or more. In this case, the ground section 10 does not need to include the protrusion 17.

[0062] FIG. 8 shows the charge distribution generated between the ground section 10 and the element section 30 when power is supplied to the ground section 10 and the element section 30 in the antenna device 1 thus formed.

[0063] 8A shows the charge distribution when the phase of the AC power is 60 degrees. In this case, the entire ground section 10 is positively charged, and the element section 30 is negatively charged. As a result, an electric field is generated between the ground section 10 and the element section 30 in the direction from the ground section 10 to the element section 30, as indicated by the arrow C.

[0064] 8B shows the charge distribution when the phase of the AC power is 150 degrees. In this case, the part of the ground section 10 farther from the power supply section 20 (the second point 12 side) is positively charged, and the part of the ground section 10 closer to the power supply section 20 (the first point 11 side) and the element section 30 are negatively charged. As a result, an electric field is generated between the part of the ground section 10 farther from the power supply section 20 and the element section 30, in the direction from the part of the ground section 10 farther from the power supply section 20 (the second point 12 side) toward the element section 30, as shown by arrow C.

[0065] 8C shows the charge distribution when the phase of the AC power is 240 degrees. In this case, the element section 30 is positively charged, and the entire ground section 10 is negatively charged. As a result, an electric field is generated between the element section 30 and the ground section 10 in the direction from the element section 30 to the ground section 10, as indicated by the arrow C.

[0066] FIG. 8D shows the charge distribution when the phase of the AC power is 330 degrees. In this case, the part of the ground section 10 closer to the power supply section 20 (first point 11 side) and the element section 30 are positively charged, and the part of the ground section 10 farther from the power supply section 20 (second point 12 side) is negatively charged. As a result, an electric field is generated between the element section 30 and the part of the ground section 10 farther from the power supply section 20, as shown by arrow C, in a direction from the element section 30 to the part of the ground section 10 farther from the power supply section 20 (second point 12 side). By continuing to supply AC power in this manner, an electric field can be generated from the board 2 that rotates around an axis perpendicular to both the first direction A and the second direction B, making it possible to transmit and receive radio waves by circular polarization as shown in FIG. 4A.

[0067] In the above embodiment, each size of the antenna device 1 has been described using a wavelength λ corresponding to the highest frequency in the frequency band used by the antenna device 1, but this is merely an example and other values ​​can also be set.

[0068] In the above embodiment, the length of the protrusion 17 along the first direction A is 0.03λ, and the length of the protrusion 17 along the second direction B is 0.11λ. For example, the length of the protrusion 17 along the first direction A may be 0.03λ, and the length of the protrusion 17 along the second direction B may be 0.23λ, or the length of the protrusion 17 along the first direction A may be 0.085λ, and the length of the protrusion 17 along the second direction B may be 0.23λ. In this case, the distance between the protrusion 17 and the element portion 30 may be 0.2λ or less (preferably 0.02 to 0.07λ).

[0069] The present invention can be used in an antenna device. [Explanation of symbols]

[0070] 1: Antenna device 2: Substrate 10: Ground section 11: 1st point 12:Second point 13: Linear section 17:Protrusion 18: Reduced width part 19: Constant width part 20: Power supply unit 30: Element section 31: First element section 32: Second element section A: 1st direction B:Second direction D1: First range D2: Second range D3: Third range

Claims

1. a ground portion including a linear portion connecting a first point and a second point along a predetermined first direction parallel to a surface of the substrate, the ground portion being formed by grounding a conductor portion of the substrate on one side of a second direction perpendicular to the first direction and parallel to the surface of the substrate; a power supply portion provided in a first range that includes the first point, among a first range, a second range, and a third range that are obtained by dividing the linear portion of the ground portion into three equal parts along the first direction; an element portion that is fed with power from the power feeding portion and that is formed in a conductor portion of the substrate insulated from the ground portion in a state where the element portion protrudes from the first range to the other side in the second direction beyond the linear portion, the element portion has a first element portion protruding from the first range to the other side in the second direction, and a second element portion extending from the first element portion along the first direction toward the second point, the ground portion has a protruding portion that protrudes to the other side in the second direction by a predetermined width from the second point side of the linear portion, The second element portion extends from the first element portion toward the protrusion portion.

2. A ground portion including a linear portion connecting a first point and a second point along a predetermined first direction parallel to a surface of the substrate, the ground portion being formed by grounding a conductor portion of the substrate on one side of a second direction perpendicular to the first direction and parallel to the surface of the substrate; a power supply portion provided in a first range that includes the first point, among a first range, a second range, and a third range that are obtained by dividing the linear portion of the ground portion into three equal parts along the first direction; an element portion that is fed with power from the power feeding portion and that is formed in a conductor portion of the substrate insulated from the ground portion in a state where the element portion protrudes from the first range to the other side in the second direction beyond the linear portion, the element portion has a first element portion protruding from the first range to the other side in the second direction, and a second element portion extending from the first element portion along the first direction toward the second point, the ground portion has a protruding portion that protrudes to the other side in the second direction by a predetermined width from the second point side of the linear portion, The second element portion extends from the first element portion toward the protruding portion, The antenna device, wherein the ground portion has a length along the second direction that is longer than a length along the first direction.

3. A ground portion including a linear portion connecting a first point and a second point along a predetermined first direction parallel to a surface of the substrate, the ground portion being formed by grounding a conductor portion of the substrate on one side of a second direction perpendicular to the first direction and parallel to the surface of the substrate; a power supply portion provided in a first range that includes the first point, among a first range, a second range, and a third range that are obtained by dividing the linear portion of the ground portion into three equal parts along the first direction; an element portion that is fed with power from the power feeding portion and that is formed in a conductor portion of the substrate insulated from the ground portion in a state where the element portion protrudes from the first range to the other side in the second direction beyond the linear portion, the element portion has a first element portion protruding from the first range to the other side in the second direction, and a second element portion extending from the first element portion along the first direction toward the second point, The antenna device, wherein the second element portion is formed so as to be gradually spaced apart from the linear portion as it approaches the second point from the first element portion.

4. A ground portion including a linear portion connecting a first point and a second point along a predetermined first direction parallel to a surface of the substrate, the ground portion being formed by grounding a conductor portion of the substrate on one side of a second direction perpendicular to the first direction and parallel to the surface of the substrate; a power supply portion provided in a first range that includes the first point, among a first range, a second range, and a third range that are obtained by dividing the linear portion of the ground portion into three equal parts along the first direction; an element portion that is fed with power from the power feeding portion and that is formed in a conductor portion of the substrate insulated from the ground portion in a state where the element portion protrudes from the first range to the other side in the second direction beyond the linear portion, the element portion has a first element portion protruding from the first range to the other side in the second direction, and a second element portion extending from the first element portion along the first direction toward the second point, The second element portion is formed so as to gradually move away from the linear portion as it approaches the second point from the first element portion, and has an antenna device having a narrowing portion whose width along a perpendicular direction perpendicular to the extension direction extending from the first element portion gradually narrows as it approaches the second point from the first element portion.

5. A ground portion including a linear portion connecting a first point and a second point along a predetermined first direction parallel to a surface of the substrate, the ground portion being formed by grounding a conductor portion of the substrate on one side of a second direction perpendicular to the first direction and parallel to the surface of the substrate; a power supply portion provided in a first range that includes the first point, among a first range, a second range, and a third range that are obtained by dividing the linear portion of the ground portion into three equal parts along the first direction; an element portion that is fed with power from the power feeding portion and that is formed in a conductor portion of the substrate insulated from the ground portion in a state where the element portion protrudes from the first range to the other side in the second direction beyond the linear portion, the element portion has a first element portion protruding from the first range to the other side in the second direction, and a second element portion extending from the first element portion along the first direction toward the second point, The second element portion is formed so as to gradually move away from the linear portion as it approaches the second point from the first element portion, and has a reduced width portion whose width along a perpendicular direction perpendicular to the extension direction extending from the first element portion gradually narrows as it approaches the second point from the first element portion, and the antenna device further has a constant width portion which is electrically connected to the reduced width portion on the second point side of the reduced width portion and has a constant width.

6. An antenna device described in any one of claims 3 to 5, wherein the length of the ground portion along the second direction is less than half of the length along the first direction.

7. An antenna device as described in claim 1 or 2, wherein the second element portion is formed so as to gradually move away from the linear portion as it approaches the second point from the first element portion.

8. The antenna device according to claim 1 , wherein the second element portion has a rectangular shape in a plan view.

Images