Antenna device

Abstract

To provide an antenna device which can improve an isolation characteristic of two polarizations of a horizontal polarization and a vertical polarization.SOLUTION: An antenna device 10 comprises a plurality of antennas 12 formed by a plurality of first antennas 32 and a plurality of second antennas 52. The plurality of first antennas 32 contain two first predetermined antennas 32P arranged along a first straight line 42. Longitudinal directions of the two first predetermined antennas 32P cross each other. Thus, a horizontal surface (a X-Y flat surface) is regulated. Each of the first antennas 32 discharges a horizontal polarization parallel to a horizontal surface. Each of the second antennas 52 discharges a vertical polarization perpendicular to the horizontal surface. Each second antenna 52 contains two second predetermined antennas 52P arranged along a second straight line 62. When projecting the first straight line 42 and the second straight line 62 in a horizontal surface, the first straight line 42 and the second straight line 62 cross alternately.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an antenna device having a plurality of antennas. [Background technology]

[0002] This type of antenna device is disclosed in, for example, Patent Document 1.

[0003] 14, Patent Document 1 discloses an antenna device 90 including a plurality of dipole antennas 92. The dipole antennas 92 are divided into a plurality of antenna groups 94 and a plurality of antenna groups 96 and arranged on a horizontal plane 91. That is, the antenna device 90 includes the antenna group 94 and the antenna group 96.

[0004] As can be seen from the arrangement of the dipole antennas 92 in FIG. 14, each dipole antenna 92 ​​corresponds to a polarized wave whose electric field oscillates parallel to a horizontal plane 91. In particular, the dipole antennas 92 of the antenna group 96 correspond to a first horizontally polarized wave whose electric field oscillates horizontally in FIG. 14 (horizontal polarization according to Patent Document 1). On the other hand, the dipole antennas 92 of the antenna group 94 correspond to a second horizontally polarized wave whose electric field oscillates vertically in FIG. 14 (vertical polarization according to Patent Document 1). The antenna groups 94 and 96 are arranged alternately. This arrangement reduces interference between the first horizontally polarized wave and the second horizontally polarized wave, thereby achieving good isolation characteristics. In other words, the technology of Patent Document 1 achieves good isolation characteristics in an antenna device 90 that transmits and receives two horizontally polarized waves in two directions parallel to a horizontal plane and perpendicular to each other. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 6-260835 Summary of the Invention [Problem to be solved by the invention]

[0006] Improved isolation characteristics are also required for antenna devices that transmit and receive two polarized waves: horizontally polarized waves in which the electric field oscillates in a direction parallel to the horizontal plane, and vertically polarized waves in which the electric field oscillates in a direction perpendicular to the horizontal plane.

[0007] Therefore, an object of the present invention is to provide an antenna device that can improve the isolation characteristics for two polarized waves, horizontally polarized wave and vertically polarized wave. [Means for solving the problem]

[0008] The present invention provides a first antenna device, An antenna device having a plurality of antennas, the antenna comprises a plurality of first antennas forming a first array and a plurality of second antennas forming a second array; the first antenna includes two first predetermined antennas; a longitudinal direction of one of the first predetermined antennas intersects with a longitudinal direction of the other of the first predetermined antennas, thereby defining a horizontal plane; each of the first antennas mainly radiates horizontally polarized waves parallel to the horizontal plane; each of the second antennas mainly radiates vertically polarized waves orthogonal to the horizontal plane; the second antenna includes two second predetermined antennas; the two first predetermined antennas are arranged along a first straight line; the two second predetermined antennas are arranged along a second straight line; When the first straight line and the second straight line are projected onto the horizontal plane along a direction perpendicular to the horizontal plane, the first straight line and the second straight line intersect with each other. An antenna device is provided.

[0009] The present invention provides a second antenna device, which is the first antenna device, one of the two first predetermined antennas is located between the two second predetermined antennas when viewed along a direction perpendicular to the second straight line and parallel to the horizontal plane; One of the two second predetermined antennas is located between the two first predetermined antennas when viewed along a direction perpendicular to the first straight line and parallel to the horizontal plane. An antenna device is provided.

[0010] The present invention provides a third antenna device, which is the first or second antenna device, When the two first predetermined antennas and the two second predetermined antennas are viewed in a direction perpendicular to the horizontal plane, the two first predetermined antennas are located within an imaginary circle having one of the two second predetermined antennas as a center and the other of the two second predetermined antennas arranged on the circumference. An antenna device is provided.

[0011] The present invention provides a fourth antenna device, which is any one of the first to third antenna devices, two adjacent first antennas in the first array are arranged to assume different attitudes from each other; Two adjacent second antennas in the second array are arranged to assume different attitudes from each other. An antenna device is provided.

[0012] The present invention provides a fifth antenna device, which is any one of the first to fourth antenna devices, the antenna device includes a reflector; The reflector is disposed along the horizontal plane, Each of the second antennas is located at least partially between the first array and the reflector in a direction perpendicular to the horizontal plane. An antenna device is provided.

[0013] The present invention provides a sixth antenna device, which is any one of the first to fifth antenna devices, the antenna device includes a shield plate; The shield plate is located between each of the first antennas and the second antenna adjacent to the first antenna. An antenna device is provided.

[0014] The present invention provides a seventh antenna device, which is any one of the first to sixth antenna devices, At least one of the first array and the second array includes at least three of the antennas arranged on a plane parallel to the horizontal plane. An antenna device is provided.

[0015] The present invention provides an eighth antenna device, which is any one of the first to seventh antenna devices, the first antenna is disposed on a plane parallel to the horizontal plane, The second antenna is disposed on a plane parallel to the horizontal plane. An antenna device is provided.

[0016] The present invention provides a ninth antenna device, which is any one of the first to eighth antenna devices, Each of the antennas forming one of the first array and the second array is located between any two of the antennas forming the other of the first array and the second array that are adjacent to each other. An antenna device is provided.

[0017] The present invention provides a tenth antenna device, which is any one of the first to ninth antenna devices, A predetermined straight line along the longitudinal direction of one of the two first predetermined antennas intersects with the other of the two first predetermined antennas. An antenna device is provided.

[0018] The present invention provides an eleventh antenna device, which is any one of the first to tenth antenna devices, the number of first antennas is four; the first antennas are arranged at four corners of an imaginary first rectangle on a plane parallel to the horizontal plane, the number of second antennas is four; the second antennas are arranged at four corners of an imaginary second rectangle on a plane parallel to the horizontal plane, The direction in which each of the four sides of the first rectangle extends intersects with the direction in which two other sides of the second rectangle that are closer than the other two sides extend. An antenna device is provided. [Effects of the Invention]

[0019] According to the present invention, when a first line connecting two first antennas radiating horizontally polarized waves and a second line connecting two second antennas radiating vertically polarized waves are projected onto a horizontal plane along a direction perpendicular to the horizontal plane, the first line and the second line intersect with each other. By arranging the two antennas radiating horizontally polarized waves so that they intersect with the two antennas radiating vertically polarized waves, it is possible to prevent each antenna from receiving radio waves radiated from the other antenna. As a result, radio wave interference (electromagnetic coupling) between the two antennas can be reduced, and good isolation characteristics can be achieved. In other words, according to the present invention, an antenna device can be provided that can improve isolation characteristics for two polarized waves, horizontally polarized waves and vertically polarized waves. [Brief explanation of the drawings]

[0020] [Figure 1] 1 is a perspective view showing an antenna device according to an embodiment of the present invention, in which the shape of the antenna is schematically drawn. [Figure 2] FIG. 2 is a plan view showing the antenna device of FIG. [Figure 3] 3 is a plan view showing the arrangement of antennas in the antenna device of FIG. 2. FIG. [Figure 4] FIG. 2 is a front view showing the antenna device of FIG. [Figure 5] FIG. 5 is a side view showing a modified example of the antenna device of FIG. [Figure 6] 5 is a front view showing another modified example of the antenna device of FIG. 4. FIG. [Figure 7] FIG. 2 is a perspective view showing a modified example of the first antenna of FIG. [Figure 8] FIG. 2 is a perspective view showing a modified example of the second antenna of FIG. [Figure 9] 2 is a perspective view showing a modified example of the antenna device of FIG. 1. The outlines of the first antenna and the second antenna are drawn with dashed lines. [Figure 10] 10 is a plan view showing the antenna device of Fig. 9, with the support member not depicted. [Figure 11] FIG. 10 is a perspective view showing a modified example of the antenna device of FIG. [Figure 12] 10 is a plan view showing another modified example of the antenna device of FIG. 9, in which the support member is not drawn. [Figure 13] 10 is a plan view showing yet another modified example of the antenna device of FIG. 9, in which the support member is not drawn. [Figure 14] FIG. 1 is a plan view showing the antenna device of Patent Document 1. DETAILED DESCRIPTION OF THE INVENTION

[0021] 1, 2 and 4, an antenna device 10 according to an embodiment of the present invention includes a plurality of antennas 12 and a support member 80 made of an insulating material. Antenna device 10 of the present embodiment is used by being incorporated into a wireless communication device (not shown) such as a wireless LAN device.

[0022] The antenna device 10 of this embodiment includes only the antenna 12 and the support member 80. However, the present invention is not limited to this. For example, the antenna device 10 may include other members in addition to the antenna 12 and the support member 80. Furthermore, the support member 80 may be provided as needed.

[0023] 1, the support member 80 of this embodiment has a base 82 and a protruding portion 84. The base 82 and the protruding portion 84 each have a rectangular shape in a horizontal plane (XY plane) defined by the front-rear direction and the left-right direction. The protruding portion 84 is located at the middle of the base 82 in the horizontal plane, and protrudes upward from the base 82 in the up-down direction perpendicular to the horizontal plane.

[0024] In this embodiment, the front-to-back direction is the X direction. In this embodiment, the front is the +X direction and the rear is the -X direction. In this embodiment, the left-to-right direction is the Y direction. In this embodiment, the right is the +Y direction and the left is the -Y direction. In this embodiment, the up-to-down direction is the Z direction. In this embodiment, the up is the +Z direction and the down is the -Z direction.

[0025] The protruding portion 84 has a first support portion 86. The first support portion 86 is the upper surface of the protruding portion 84. The base portion 82 has a second support portion 88. The second support portion 88 is the upper surface of the base portion 82. In this embodiment, the first support portion 86 and the second support portion 88 are each flat surfaces parallel to the horizontal plane with no irregularities. However, the present invention is not limited to this. For example, the first support portion 86 and the second support portion 88 may each have irregularities. The first support portion 86 and the second support portion 88 may each be a flat surface with a step or a slope with a step. Furthermore, the first support portion 86 and the second support portion 88 may each be a curved surface that is parallel to the horizontal plane as a whole.

[0026] The antennas 12 of this embodiment have the same linear shape. More specifically, each of the antennas 12 is a dipole antenna. Each of the antennas 12 has a power feed portion 122. The power feed portion 122 of each of the antennas 12 is connected to a transmitter / receiver (not shown) via a feed line (not shown). Each of the antennas 12 transmits radio waves based on a signal fed from the transmitter / receiver via the feed line, and transmits a signal based on the received radio waves to the transmitter / receiver via the feed line.

[0027] As described above, each of the antennas 12 in this embodiment is a single rod-shaped dipole antenna having a linear shape. However, the present invention is not limited to this. For example, each of the antennas 12 may be a linear inverted-L antenna or a linear inverted-F antenna. Each of the antennas 12 may be a multipole antenna having multiple rod-shaped portions. Furthermore, each of the antennas 12 may be a planar patch antenna or a planar inverted-F antenna.

[0028] The antenna 12 comprises a plurality of first antennas 32 forming the first array 30 and a plurality of second antennas 52 forming the second array 50. In other words, all of the first antennas 32 form the first array 30, and all of the second antennas 52 form the second array 50. The first array 30 of this embodiment includes four first antennas 32. The second array 50 of this embodiment includes four second antennas 52. However, the present invention is not limited to this. For example, the first array 30 may include two or more first antennas 32. The second array 50 may include two or more second antennas 52. That is, the number of first antennas 32 may be two, and the number of second antennas 52 may be two. The number of first antennas 32 may be five or more, and the number of second antennas 52 may be five or more.

[0029] 1, 2, and 4, the first array 30 of this embodiment is disposed on the first support portion 86 of the support member 80. More specifically, each of the first antennas 32 is located on the first support portion 86 and extends along the first support portion 86. That is, the longitudinal direction of each of the first antennas 32 extends parallel to the horizontal plane. Referring to FIG. 2, each of the first antennas 32 disposed in this manner can transmit and receive horizontally polarized waves in which the electric field EF oscillates in a direction parallel to the horizontal plane. In other words, each of the first antennas 32 mainly radiates horizontally polarized waves parallel to the horizontal plane.

[0030] 1, 2, and 4, the second array 50 of this embodiment is disposed on the second support portion 88 of the support member 80. More specifically, each of the second antennas 52 is located on the second support portion 88 and extends upward from the second support portion 88. That is, the longitudinal direction of each of the second antennas 52 extends along the up-down direction. Referring to FIG. 4, each of the second antennas 52 disposed in this manner is capable of transmitting and receiving vertically polarized waves in which the electric field EF oscillates in a direction perpendicular to the horizontal plane. In other words, each of the second antennas 52 mainly radiates vertically polarized waves perpendicular to the horizontal plane.

[0031] Since each of the antennas 12 in this embodiment has a linear shape, the longitudinal direction is the direction in which the antenna 12 extends. On the other hand, if each of the antennas 12 has a plurality of rod-shaped portions or has a planar shape, the longitudinal direction may be defined as the direction in which the long side of an imaginary rectangle circumscribing the antenna 12 extends.

[0032] 1 and 4, each of the first antennas 32 of this embodiment is supported by a single first support portion 86, and thus positioned on a common plane parallel to the horizontal plane. Also, each of the second antennas 52 of this embodiment is supported by a single second support portion 88, and thus the lower ends of each of the second antennas 52 are positioned on a common plane parallel to the horizontal plane.

[0033] However, the present invention is not limited to this embodiment. For example, the first antennas 32 may be supported by different support parts, and the second antennas 52 may be supported by different support parts. More specifically, the first antennas 32 and the second antennas 52 may be supported by eight separate support members instead of a single support member 80. The first antennas 32 may be located at different positions in the vertical direction. The lower ends of the second antennas 52 may be located at different positions in the vertical direction.

[0034] 1, 2, and 4, the first antenna 32 includes two first predetermined antennas 32P. The longitudinal direction of one of the first predetermined antennas 32P intersects with the longitudinal direction of the other of the first predetermined antennas 32P, thereby defining a horizontal plane.

[0035] Specifically, when the two first predetermined antennas 32P of this embodiment are extended along their longitudinal directions, they intersect at right angles on a common plane parallel to the horizontal. However, the present invention is not limited to this. For example, when the two first predetermined antennas 32P are extended along their longitudinal directions, they may intersect obliquely on a common plane parallel to the horizontal. The positions of the two first predetermined antennas 32P in the vertical direction may be different from each other. That is, the two first predetermined antennas 32P may be skewed relative to each other. Furthermore, the longitudinal directions of the two first predetermined antennas 32P may intersect on a plane (predetermined plane) that intersects with the horizontal plane of this embodiment. In this case, this predetermined plane may be defined as the horizontal plane instead of the horizontal plane of this embodiment.

[0036] The second antenna 52 includes two second predetermined antennas 52P. In this embodiment, the longitudinal directions of the two second predetermined antennas 52P extend parallel to each other along the vertical direction. However, the present invention is not limited to this. For example, the longitudinal directions of the two second predetermined antennas 52P may intersect each other when viewed along a horizontal plane.

[0037] 1 and 2, the two first predetermined antennas 32P are arranged along a first straight line 42. The two second predetermined antennas 52P are arranged along a second straight line 62. In this embodiment, the first straight line 42 extends through the power feed portions 122 of the two first predetermined antennas 32P. In this embodiment, the second straight line 62 extends through the power feed portions 122 of the two second predetermined antennas 52P. However, the present invention is not limited to this. For example, if each of the first antennas 32 has multiple rod-shaped portions or a planar shape, the first straight line 42 may be defined as a line passing through the center of gravity of each of the figures obtained by projecting the two first predetermined antennas 32P onto a horizontal plane along the vertical direction. Similarly, the second straight line 62 may be defined as a line passing through the center of gravity of each of the figures obtained by projecting the two second predetermined antennas 52P onto a horizontal plane along the vertical direction.

[0038] In this embodiment, the first straight line 42 and the second straight line 62 each extend parallel to a horizontal plane. However, the present invention is not limited to this. For example, the first straight line 42 and the second straight line 62 each may intersect with the horizontal plane.

[0039] 2, when the first line 42 and the second line 62 are projected onto a horizontal plane along the up-down direction perpendicular to the horizontal plane, the first line 42 and the second line 62 intersect with each other. In other words, when the first line 42 connecting the two first antennas 32 that radiate horizontally polarized waves and the second line 62 connecting the two second antennas 52 that radiate vertically polarized waves are projected onto the horizontal plane along the direction perpendicular to the horizontal plane, the first line 42 and the second line 62 intersect with each other.

[0040] As described above, the two antennas 12 (two first predetermined antennas 32P) that radiate horizontally polarized waves are arranged so that their longitudinal directions intersect with each other. In addition, the two first predetermined antennas 32P that radiate horizontally polarized waves are arranged so that they intersect with the two antennas 12 (two second predetermined antennas 52P) that radiate vertically polarized waves. Hereinafter, the above-described arrangement will be referred to as a "cross arrangement."

[0041] The above-described crossed arrangement can reduce radio wave interference (electromagnetic coupling) between the two first antennas 32 that radiate horizontally polarized waves. In addition, it can reduce radio wave interference between the first antenna 32 that radiates horizontally polarized waves and the second antenna 52 that radiates vertically polarized waves. As a result, good isolation characteristics can be obtained. As described above, the antenna device 10 of this embodiment can improve the isolation characteristics between horizontally polarized waves and between horizontally polarized waves and vertically polarized waves. In other words, this embodiment can provide an antenna device 10 that can improve the isolation characteristics for two polarized waves, horizontally polarized waves and vertically polarized waves.

[0042] According to this embodiment, every two adjacent first antennas 32 are arranged crosswise with respect to any two adjacent second antennas 52. In other words, every two adjacent first antennas 32 can be defined as two first predetermined antennas 32P. Furthermore, two second antennas 52 arranged crosswise with respect to the first predetermined antennas 32P can be defined as two second predetermined antennas 52P. According to this embodiment, better isolation characteristics can be obtained. However, the present invention is not limited to this. For example, only two of the first antennas 32 may be arranged crosswise with respect to only two of the second antennas 52. In other words, only two of the first antennas 32 may be first predetermined antennas 32P, and only two of the second antennas 52 may be second predetermined antennas 52P.

[0043] 3, according to this embodiment, when the two first predetermined antennas 32P and the two second predetermined antennas 52P are viewed in the up-down direction perpendicular to the horizontal plane, the two first predetermined antennas 32P are located within an imaginary circle 20 having one of the two second predetermined antennas 52P at the center and the other of the two second predetermined antennas 52P disposed on the circumference. In other words, the distance between one of the second predetermined antennas 52P and each of the first predetermined antennas 32P is smaller than the radius CR of the imaginary circle 20. In other words, the two first predetermined antennas 32P are disposed close to the two second predetermined antennas 52P (hereinafter referred to as "closely disposed").

[0044] In this embodiment, the first predetermined antenna 32P is disposed crosswise relative to the second predetermined antenna 52P. Therefore, even if the first predetermined antenna 32P is disposed close to the second predetermined antenna 52P, the polarized waves of the first predetermined antenna 32P and the polarized waves of the second predetermined antenna 52P can be prevented from interfering with each other, thereby improving isolation characteristics. For example, even if multiple antennas 12 are disposed close to each other inside a wireless communication device (not shown), radio wave interference between the antennas 12 disposed crosswise can be reduced. However, the present invention is not limited to this. For example, the two first predetermined antennas 32P may be located outside the imaginary circle 20.

[0045] Referring to FIG. 4, the first array 30 of this embodiment is located above the second array 50. Because the first array 30 is spaced apart from the second array 50 in the vertical direction, radio wave interference between the first antenna 32 that radiates horizontally polarized waves and the second antenna 52 that radiates vertically polarized waves can be further reduced. However, the present invention is not limited to this. For example, the first array 30 may be located at the same position as the second array 50 in the vertical direction. On the other hand, the first array 30 may be located further above the first array 30 depicted in FIG. 4 or below the second array 50.

[0046] Explaining Fig. 5 more specifically while comparing it with Fig. 1, the illustrated antenna device 10A is a modified example of the antenna device 10. The antenna device 10A has a similar structure to the antenna device 10, except that it includes a support member 80A instead of the support member 80. The support member 80A has a support portion 88A. The support portion 88A is the upper surface of the support member 80A and is a plane that extends parallel to the horizontal plane.

[0047] The antenna device 10A has the same four first antennas 32 and four second antennas 52 as the antenna device 10. The horizontal arrangement of the first antennas 32 and second antennas 52 is the same as that of the antenna device 10. Meanwhile, the first antennas 32 and second antennas 52 are supported by a common support part 88A. That is, the first array 30 is in the same position as the second array 50 in the vertical direction. This modification also enables the isolation characteristics to be improved, similar to the antenna device 10.

[0048] The aforementioned close arrangement of the first predetermined antenna 32P and the second predetermined antenna 52P can be explained from another perspective. More specifically, with reference to Fig. 4 in conjunction with Fig. 2, one of the two first predetermined antennas 32P is located between the two second predetermined antennas 52P when viewed along a direction perpendicular to the second straight line 62 and parallel to the horizontal plane. With reference to Fig. 5 in conjunction with Fig. 2, one of the two second predetermined antennas 52P is located between the two first predetermined antennas 32P when viewed along a direction perpendicular to the first straight line 42 and parallel to the horizontal plane.

[0049] In this embodiment, the first predetermined antennas 32P and the second predetermined antennas 52P are arranged as described above. However, the present invention is not limited to this. For example, when viewed along a direction perpendicular to the second straight line 62 and parallel to the horizontal plane, two first predetermined antennas 32P may be located between two second predetermined antennas 52P. When viewed along a direction perpendicular to the first straight line 42 and parallel to the horizontal plane, two second predetermined antennas 52P may be located between two first predetermined antennas 32P.

[0050] Referring to FIG. 1 , the four first antennas 32 of this embodiment are arranged on a plane parallel to the horizontal plane. In other words, the first array 30 of this embodiment includes four first antennas 32 arranged on a plane parallel to the horizontal plane. Furthermore, the four second antennas 52 of this embodiment are arranged on a plane parallel to the horizontal plane. In other words, the second array 50 of this embodiment includes four second antennas 52 arranged on a plane parallel to the horizontal plane. However, the present invention is not limited to this. For example, only three of the first antennas 32 may be arranged on a common plane parallel to the horizontal plane, or only three of the second antennas 52 may be arranged on a common plane parallel to the horizontal plane. That is, at least one of the first array 30 and the second array 50 may include at least three antennas 12 arranged on a plane parallel to the horizontal plane.

[0051] The arrangement of the first antenna 32 and the second antenna 52 according to this embodiment for improving the isolation characteristics will be further described below from various viewpoints.

[0052] Referring to FIG. 2 , each of the antennas 12 (first antennas 32) forming the first array 30 of the present embodiment is located between any two adjacent antennas 12 (second antennas 52) of the antennas 12 (second antennas 52) forming the second array 50. For example, the front first antenna 32 is located between the two front second antennas 52. However, the present invention is not limited to this. For example, each of the second antennas 52 forming the second array 50 may be located between any two adjacent first antennas 32 of the first antennas 32 forming the first array 30. In other words, each of the antennas 12 forming one of the first array 30 and the second array 50 may be located between any two adjacent antennas 12 of the antennas 12 forming the other of the first array 30 and the second array 50.

[0053] 3, according to this embodiment, a predetermined straight line 48 along the longitudinal direction of one of the two first predetermined antennas 32P intersects with the other of the two first predetermined antennas 32P. However, the present invention is not limited to this, and the predetermined straight line 48 may be spaced apart to some extent from the other of the two first predetermined antennas 32P.

[0054] According to this embodiment, the number of first antennas 32 is four, and the number of second antennas 52 is four. The first antennas 32 are arranged at the four corners of an imaginary first rectangle 44 on a plane parallel to the horizontal plane. The second antennas 52 are arranged at the four corners of an imaginary second rectangle 64 on a plane parallel to the horizontal plane.

[0055] According to this embodiment, when the first rectangle 44 and the second rectangle 64 are viewed in the up-down direction, the center position of the first rectangle 44 in the horizontal plane coincides with the center position of the second rectangle 64 in the horizontal plane. Furthermore, the first rectangle 44 is inclined at a predetermined angle with respect to the second rectangle 64. The four vertices of the first rectangle 44 are outside the second rectangle 64, and the four vertices of the second rectangle 64 are outside the first rectangle 44. As a result, the extension direction of each of the four sides 46 of the first rectangle 44 intersects with the extension direction of two of the four sides 66 of the second rectangle 64 that are closer than two of the four sides 66. In particular, according to this embodiment, each of the four sides 46 of the first rectangle 44 intersects with the extension direction of two of the four sides 66 of the second rectangle 64 that are closer than two of the four sides 66.

[0056] In this embodiment, the first antenna 32 and the second antenna 52 are arranged as described above. However, the present invention is not limited to this. For example, when the first rectangle 44 and the second rectangle 64 are viewed in the up-down direction, the first rectangle 44 may be located inside the second rectangle 64, or the second rectangle 64 may be located inside the first rectangle 44. The first rectangle 44 and the second rectangle 64 may partially overlap each other.

[0057] In addition to the modifications already described, this embodiment can be further modified in various ways. Modifications of this embodiment will be described below.

[0058] Comparing Fig. 6 with Fig. 4, the antenna device 10B according to the modified example includes a reflector 16B that is not provided in the antenna device 10. Furthermore, the antenna device 10B includes four second antennas 52B instead of the second antenna 52 of the antenna device 10. Except for the above-mentioned differences, the antenna device 10B has the same structure as the antenna device 10. However, the present invention is not limited to this. For example, the support member 80 may be provided as needed.

[0059] 6, the reflector 16B of this modified example is a flat metal plate. The reflector 16B is located on the second support portion 88 of the support member 80. The reflector 16B extends along a horizontal plane. That is, the reflector 16B is disposed parallel to the horizontal plane.

[0060] The second antennas 52B of this modification have the same linear shape. More specifically, each of the second antennas 52B is a monopole antenna. Each of the second antennas 52B has a power feeder 122. The lower end of the power feeder 122 is connected to the reflector 16B. Each of the second antennas 52B is disposed on the reflector 16B and extends upward in the vertical direction from the reflector 16B. That is, the longitudinal direction of each of the second antennas 52B extends in the vertical direction. As described above, each of the second antennas 52B disposed on the metal reflector 16B can transmit and receive vertically polarized waves in which the electric field EF oscillates in a direction perpendicular to the horizontal plane. In other words, each of the second antennas 52B mainly radiates vertically polarized waves perpendicular to the horizontal plane.

[0061] 6 together with Fig. 1, the first antenna 32 and the second antenna 52B of this modification are arranged in the same manner as the first antenna 32 and the second antenna 52 of the antenna device 10. According to this modification, it is possible to provide an antenna device 10B that can improve the isolation characteristics for two polarized waves, horizontally polarized wave and vertically polarized wave.

[0062] Referring to FIG. 6 , each of the second antennas 52B of this modified example is located completely between the first array 30 and the reflector 16B in the vertical direction perpendicular to the horizontal plane. That is, the second array 50 of this modified example is located closer to the reflector 16B than the first array 30. This arrangement can improve isolation characteristics. However, the present invention is not limited to this. For example, the height of the antenna device 10B may be reduced by reducing the vertical size of the protrusion 84. For example, the first array 30 may be located on the upper surface of the protrusion 84, which is flush with the upper surface of the reflector 16B. Each of the second antennas 52B may be located at least partially between the first array 30 and the reflector 16B in the direction perpendicular to the horizontal plane.

[0063] Comparing Fig. 9 with Fig. 1, antenna device 10C according to another modification has different components from antenna device 10. On the other hand, as will be described below, antenna device 10C has a similar structure to antenna device 10 and can be modified in the same way as antenna device 10.

[0064] Referring to FIG. 9, the antenna device 10C includes multiple antennas 12C, a metal reflector 16C, and a support member 80C made of an insulator. The reflector 16C may be made of any metal. For example, the reflector 16C may be a metal plate such as sheet metal or die-cast metal. Alternatively, the antenna device 10C may be provided with a substrate (not shown) of a size similar to the illustrated reflector 16C, and the ground of this substrate may be used as the reflector 16C. The antenna 12C includes multiple first antennas 32C forming a first array 30 and multiple second antennas 52C forming a second array 50. The reflector 16C extends along a horizontal plane. That is, the reflector 16C is disposed parallel to the horizontal plane. The support member 80C protrudes upward from the reflector 16C. The support member 80C has an upper surface extending parallel to the horizontal plane.

[0065] The first antenna 32C and the second antenna 52C are each disposed above the reflector 16C. More specifically, the second antennas 52C are each disposed directly on the reflector 16C. Meanwhile, the first antennas 32C are each disposed on the upper surface of the support member 80C. That is, the first antennas 32C are each disposed at a distance from the reflector 16C.

[0066] The antenna device 10C of this modified example includes the above-described components. However, the present invention is not limited to this. For example, the reflector 16C may be provided as needed. Furthermore, the reflector 16C may be provided only in a portion corresponding to the second antenna 52C.

[0067] In this modified example, the first antennas 32C are located on a common plane parallel to the horizontal plane. The second antennas 52C are located on a common plane parallel to the horizontal plane. However, the present invention is not limited to this. For example, the positions of the four first antennas 32C and the four second antennas 52C in the vertical direction may be different from each other. Each second antenna 52C may be located at least partially between the first array 30 and the reflector 16C in the vertical direction perpendicular to the horizontal plane.

[0068] 7, each of the first antennas 32C of this modification is an antenna having a split ring resonant structure. Each of the first antennas 32C includes a metal conductor 322C and a rectangular substrate 328C. The substrate 328C is made of a material such as glass epoxy. A ground (not shown) and a pattern (not shown) made of a conductive metal such as copper are formed on the substrate 328C. The conductor 322C is mounted on the substrate 328C and connected to the pattern and the ground.

[0069] The conductor portion 322C has splits 324C with an interdigital structure. That is, the conductor portion 322C functions as a split ring resonator. Each of the conductor portions 322C is mounted on a substrate 328C so as to extend along a horizontal plane as a whole. Each of the first antennas 32C is connected to a transceiver unit (not shown), for example, via a feeder line (not shown) provided on the substrate 328C. Each of the first antennas 32C arranged as described above mainly radiates horizontally polarized waves parallel to the horizontal plane.

[0070] When first antenna 32C is viewed in the vertical direction, the center of gravity of first antenna 32C is located near the center of the horizontal plane of rectangular substrate 328C. The longitudinal direction of first antenna 32C is the direction in which the long sides of substrate 328C extend. The longitudinal direction of first antenna 32C shown in FIG. 7 extends along the left-right direction.

[0071] According to the first antenna 32C of this modification, various components such as inductor components, capacitor components, and resistor components can be mounted on the substrate 328C. The impedance of the first antenna 32C can be adjusted by the mounted inductor components, capacitor components, and resistor components. In other words, a first antenna 32C can be obtained that can be adjusted to have a predetermined impedance for a predetermined frequency as needed.

[0072] Referring to FIG. 8, each of the second antennas 52C of this modification is an antenna having a split ring resonant structure. Each of the second antennas 52C includes a metal conductor 522C and a rectangular substrate 528C. The substrate 528C is made of a material such as glass epoxy. A ground (not shown) and a pattern (not shown) made of a conductive metal such as copper are formed on the substrate 528C. The conductor 522C is mounted on the substrate 528C and connected to the pattern and the ground. When each of the second antennas 52C is placed on a reflector 16C (see FIG. 9), the ground of the substrate 528C is connected to the reflector 16C. On the other hand, if the ground (not shown) of the substrate (not shown) is used as the reflector 16C as described above, the conductor 522C may be mounted on the substrate and directly connected to the ground of the substrate.

[0073] A split 524C is formed in the conductor portion 522C. That is, the conductor portion 522C functions as a split ring resonator. Each of the conductor portions 522C is mounted on the substrate 528C so as to extend along a plane perpendicular to the horizontal plane as a whole. Each of the second antennas 52C is connected to a transceiver unit (not shown), for example, via a feeder line (not shown) provided on the substrate 528C. Each of the second antennas 52C arranged as described above mainly radiates vertically polarized waves perpendicular to the horizontal plane.

[0074] When the second antenna 52C is viewed in the vertical direction, the center of gravity of the second antenna 52C is located near the center of the horizontal plane of the substrate 528C. The longitudinal direction of the second antenna 52C is the direction in which the long sides of the substrate 528C extend. The longitudinal direction of the second antenna 52C shown in FIG. 8 extends along the left-right direction.

[0075] According to the second antenna 52C of this modification, various components such as inductor components, capacitor components, and resistor components can be mounted on the substrate 528C. The impedance of the second antenna 52C can be adjusted by the mounted inductor components, capacitor components, and resistor components. In other words, a second antenna 52C can be obtained that can be adjusted to have a predetermined impedance for a predetermined frequency as needed.

[0076] Referring to Fig. 7, an antenna such as the first antenna 32C is disclosed in Japanese Patent Application Laid-Open No. 2020-145541 and WO2019 / 198588A1. Referring to Fig. 8, an antenna such as the second antenna 52C is disclosed in Japanese Patent Application Laid-Open No. 2021-004233.

[0077] 10, the first antenna 32C of the antenna device 10C includes two first predetermined antennas 32P. The second antenna 52C of the antenna device 10C includes two second predetermined antennas 52P. The longitudinal direction of one of the first predetermined antennas 32P intersects with the longitudinal direction of the other of the first predetermined antennas 32P, thereby defining a horizontal plane.

[0078] The two first predetermined antennas 32P are arranged along a first straight line 42. The two second predetermined antennas 52P are arranged along a second straight line 62. When the first straight line 42 and the second straight line 62 are projected onto a horizontal plane along the up-down direction perpendicular to the horizontal plane, the first straight line 42 and the second straight line 62 intersect with each other. That is, the first predetermined antenna 32P is arranged to intersect with the second predetermined antenna 52P, similar to the antenna device 10 (see FIG. 1). This modification can provide an antenna device 10C that can improve the isolation characteristics for two polarized waves, horizontally polarized and vertically polarized.

[0079] 10, the first antennas 32C of this modified example have the same shape. The second antennas 52C of this modified example have the same shape. Two adjacent first antennas 32C in the first array 30 are arranged to assume different postures. Two adjacent second antennas 52C in the second array 50 are arranged to assume different postures. Specifically, two adjacent second antennas 52C are arranged so that their longitudinal directions intersect with each other.

[0080] The four first antennas 32C of this modified example are arranged so that the same portion (the rear end of the conductor portion 322C in FIG. 7) faces in directions that intersect with each other at an angle close to 90°. The four second antennas 52C of this modified example are arranged so that the same portion (the front surface of the conductor portion 522C in FIG. 8) faces in directions that intersect with each other at an angle close to 90°. In particular, the four first antennas 32C of this modified example are arranged with four-fold symmetry in the horizontal plane. The second antennas 52C of this modified example are arranged with four-fold symmetry in the horizontal plane.

[0081] According to the antenna device 10C of this modified example, radio wave interference between the antennas 12C can be further reduced. However, the present invention is not limited to this. For example, the first antennas 32C may be arranged so that they have the same orientation. The second antennas 52C may be arranged so that they have the same orientation. The four first antennas 32C may be arranged so that the same portions face directions that intersect at a predetermined angle, or may be arranged asymmetrically in the horizontal plane. The second antennas 52C may be arranged so that the same portions face directions that intersect at a predetermined angle, or may be arranged asymmetrically in the horizontal plane.

[0082] The first antenna 32C including the first predetermined antenna 32P and the second antenna 52C including the second predetermined antenna 52P are arranged in the same manner as in the antenna device 10 (see FIG. 1). The arrangement of the first antenna 32C and the second antenna 52C can be modified in the same manner as in the antenna device 10. The arrangement of the first antenna 32C and the second antenna 52C in this modified example will be described below.

[0083] 10, one of the two first predetermined antennas 32P is located between the two second predetermined antennas 52P when viewed along a direction orthogonal to the second straight line 62 and parallel to the horizontal plane. One of the two second predetermined antennas 52P is located between the two first predetermined antennas 32P when viewed along a direction orthogonal to the first straight line 42 and parallel to the horizontal plane.

[0084] When the two first predetermined antennas 32P and the two second predetermined antennas 52P are viewed in the vertical direction perpendicular to the horizontal plane, the two first predetermined antennas 32P are located within an imaginary circle 20 with one of the two second predetermined antennas 52P at the center and the other of the two second predetermined antennas 52P arranged on the circumference.

[0085] The first antenna 32C is arranged on a plane parallel to the horizontal plane. The second antenna 52C is arranged on a plane parallel to the horizontal plane. In other words, the first array 30 includes four antennas 12C (first antennas 32C) arranged on a plane parallel to the horizontal plane. The second array 50 includes four antennas 12C (second antennas 52C) arranged on a plane parallel to the horizontal plane. That is, at least one of the first array 30 and the second array 50 includes at least three antennas 12C arranged on a plane parallel to the horizontal plane.

[0086] Each of the antennas 12C (first antennas 32C) forming the first array 30 is located between any two adjacent antennas 12C of the antennas 12C (second antennas 52C) forming the second array 50. In other words, each of the antennas 12C forming one of the first array 30 and the second array 50 is located between any two adjacent antennas 12C of the antennas 12C forming the other of the first array 30 and the second array 50.

[0087] According to this modification, the predetermined straight line 48 along the longitudinal direction of one of the two first predetermined antennas 32P is spaced apart from the other of the two first predetermined antennas 32P. However, the present invention is not limited to this. For example, each of the first antennas 32C may be disposed at the position indicated by the dashed dotted line in FIG. 10. In this case, the predetermined straight line 48 intersects with the other of the two first predetermined antennas 32P.

[0088] There are four first antennas 32C and four second antennas 52C. The first antennas 32C are arranged at the four corners of an imaginary first rectangle 44 on a plane parallel to the horizontal plane. The first rectangle 44 is a rectangle that circumscribes the four first antennas 32C and does not coincide with the outline of the support member 80C (see FIG. 9). The second antennas 52C are arranged at the four corners of an imaginary second rectangle 64 on a plane parallel to the horizontal plane. The second rectangle 64 is a rectangle that circumscribes the four second antennas 52C and does not coincide with the outline of the reflector 16C. The direction in which each of the four sides 46 of the first rectangle 44 extends is the same as the direction in which two of the four sides 66 of the second rectangle 64 extend. 66 The other two sides are closer than 66 The directions intersect with the direction in which the lines extend.

[0089] Comparing Fig. 11 with Fig. 9, antenna device 10D, which is a variation of antenna device 10C, includes multiple shield plates 18D that are not included in antenna device 10C. Apart from this difference, antenna device 10D has the same structure as antenna device 10C.

[0090] The shield plates 18D of this modified example are provided corresponding to the first antennas 32C, respectively. Each of the shield plates 18D is a metal plate. Each of the shield plates 18D is connected to the reflector 16C. The shield plates 18D are located between each of the first antennas 32C and the second antenna 52C located closest to (near) the first antenna 32C. More specifically, each of the shield plates 18D is located between the corresponding first antenna 32C and the second antenna 52C located closest to (near) the corresponding first antenna 32C. By providing the shield plates 18D, the isolation characteristics can be further improved.

[0091] The shield plates 18D of this modified example surround each second antenna 52C and are provided so as to shield the second antenna 52C from the interior of the area above the reflector 16C. Each of the shield plates 18D is provided only on the upper surface of the reflector 16C. Each of the shield plates 18D extends upward from the reflector 16C. Each of the shield plates 18D has a protruding portion 182D. The protruding portion 182D is located at the upper end of the shield plate 18D and protrudes toward the second antenna 52C. Each of the shield plates 18D of this modified example has the structure described above. However, the present invention is not limited to this. For example, the structure and arrangement of each of the shield plates 18D can be modified as needed.

[0092] Each of the shield plates 18D in this modified example is directly fixed to the upper surface of the reflector 16C. However, the present invention is not limited to this. For example, as shown in the enlarged view of FIG. 11 , each of the shield plates 18D may be fixed to the upper surface of the reflector 16C via a gap member 188D made of an insulating material. In other words, a gap may be formed between each of the shield plates 18D and the reflector 16C in the vertical direction.

[0093] Comparing Figure 12 with Figure 11, antenna device 10E according to another modification includes a shield plate 18E that is different from shield plate 18D of antenna device 10D. Furthermore, the arrangement of first antenna 32C of antenna device 10E is slightly different from that of antenna device 10D. Except for the above-mentioned differences, antenna device 10E has a similar structure to antenna device 10D and functions similarly to antenna device 10D. This modification provides antenna device 10E that can improve the isolation characteristics for two polarized waves, horizontally polarized and vertically polarized.

[0094] Referring to FIG. 12, the shield plate 18E of this modification is fixed to the upper surface of the reflector 16C via a gap member 188D (see FIG. 11) made of an insulator, similar to the shield plate 18D (see FIG. 11). Similarly to the shield plate 18D, the shield plate 18E extends upward from the reflector 16C. The shield plate 18E is located between each of the first antennas 32C and the second antenna 52C that is closest to the first antenna 32C. According to this modification, two separate shield plates 18E are disposed between the first antenna 32C and the second antenna 52C. However, the present invention is not limited to this. For example, three or more separate shield plates 18E may be disposed between the first antenna 32C and the second antenna 52C. Each of the shield plates 18E may be directly fixed to the reflector 16C without the gap member 188D.

[0095] Comparing Figure 13 with Figure 11, an antenna device 10F according to yet another modification includes a shield plate 18F that is different from the shield plate 18D of the antenna device 10D. Furthermore, the arrangement of the first antenna 32C of the antenna device 10F is slightly different from that of the antenna device 10D. Except for the above-mentioned differences, the antenna device 10F has a similar structure to the antenna device 10D and functions similarly to the antenna device 10D. This modification provides an antenna device 10F that can improve the isolation characteristics for two polarized waves, horizontally polarized and vertically polarized.

[0096] Referring to FIG. 13, the shield plate 18F of this modification, like the shield plate 18D (see FIG. 11), is fixed to the upper surface of the reflector 16C via a gap member 188D (see FIG. 11) made of an insulator. Like the shield plate 18D, the shield plate 18F extends upward from the reflector 16C. The shield plate 18F is located between each of the first antennas 32C and the second antenna 52C located closest to (near) the first antenna 32C. According to this modification, the first antenna 32C and the second antenna 52C are separated from each other by a single shield plate 18F. However, the present invention is not limited to this. For example, the first antenna 32C and the second antenna 52C may be separated from each other by two separate shield plates 18F. Each of the shield plates 18F may be directly fixed to the reflector 16C without the gap member 188D. [Explanation of symbols]

[0097] 10, 10A, 10B, 10C, 10D, 10E, 10F Antenna device 12,12C Antenna 122 Power supply unit 16B,16C Reflector 18D, 18E, 18F Shield plate 182D Overhang 188D Gap member 20 Virtual Circle 30 1st Array 32,32C First antenna 322C Conductor 324C Split 328C board 32P First designated antenna 42 1st straight line 44 1st rectangle 46 sides 48 Predetermined straight line 50 Second Array 52, 52B, 52C Second antenna 522C Conductor 524C Split 528C board 52P Second designated antenna 62 Second straight line 64 2nd rectangle 66 sides 80, 80A, 80C Support member 82 Base 84 Protrusion 86 1st support part 88 Second support part 88A Support part EF electric field

Claims

1. An antenna device having a plurality of antennas, the antenna comprises a plurality of first antennas forming a first array and a plurality of second antennas forming a second array; the first antenna includes two first predetermined antennas; a longitudinal direction of one of the first predetermined antennas intersects with a longitudinal direction of the other of the first predetermined antennas, thereby defining a horizontal plane; each of the first antennas mainly radiates horizontally polarized waves parallel to the horizontal plane; each of the second antennas mainly radiates vertically polarized waves orthogonal to the horizontal plane; the second antenna includes two second predetermined antennas; the two first predetermined antennas are arranged along a first straight line; the two second predetermined antennas are arranged along a second straight line; When the first straight line and the second straight line are projected onto the horizontal plane along a direction perpendicular to the horizontal plane, the first straight line and the second straight line intersect with each other, Each of the first antennas is an antenna having a split ring resonant structure, and includes a rectangular first substrate parallel to the horizontal plane and a first conductor portion mounted on the first substrate, Each of the second antennas is an antenna having a split ring resonant structure, and includes a rectangular second substrate parallel to the horizontal plane and a second conductor portion mounted on the second substrate. Antenna device.

2. 2. The antenna device according to claim 1, one of the two first predetermined antennas is located between the two second predetermined antennas when viewed along a direction perpendicular to the second straight line and parallel to the horizontal plane; One of the two second predetermined antennas is located between the two first predetermined antennas when viewed along a direction perpendicular to the first straight line and parallel to the horizontal plane. Antenna device.

3. 3. The antenna device according to claim 1, When the two first predetermined antennas and the two second predetermined antennas are viewed in a direction perpendicular to the horizontal plane, the two first predetermined antennas are located within an imaginary circle having one of the two second predetermined antennas as a center and the other of the two second predetermined antennas arranged on the circumference. Antenna device.

4. The antenna device according to any one of claims 1 to 3, two adjacent first antennas in the first array are arranged to assume different attitudes from each other; Two adjacent second antennas in the second array are arranged to assume different attitudes from each other. Antenna device.

5. The antenna device according to any one of claims 1 to 4, the antenna device includes a reflector; The reflector is disposed along the horizontal plane, Each of the second antennas is located at least partially between the first array and the reflector in a direction perpendicular to the horizontal plane. Antenna device.

6. 6. The antenna device according to claim 1, the antenna device includes a shield plate; The shield plate is located between each of the first antennas and the second antenna adjacent to the first antenna. Antenna device.

7. 7. The antenna device according to claim 1, At least one of the first array and the second array includes at least three of the antennas arranged on a plane parallel to the horizontal plane. Antenna device.

8. An antenna device according to any one of claims 1 to 7, the first antenna is disposed on a plane parallel to the horizontal plane, The second antenna is disposed on a plane parallel to the horizontal plane. Antenna device.

9. An antenna device according to any one of claims 1 to 8, Each of the antennas forming one of the first array and the second array is located between any two of the antennas forming the other of the first array and the second array that are adjacent to each other. Antenna device.

10. 10. The antenna device according to claim 1, A predetermined straight line along the longitudinal direction of one of the two first predetermined antennas intersects with the other of the two first predetermined antennas. Antenna device.

11. An antenna device according to any one of claims 1 to 10, the number of first antennas is four; the first antennas are arranged at four corners of an imaginary first rectangle on a plane parallel to the horizontal plane, the number of second antennas is four; the second antennas are arranged at four corners of an imaginary second rectangle on a plane parallel to the horizontal plane, The direction in which each of the four sides of the first rectangle extends intersects with the direction in which two other sides of the second rectangle that are closer than the other two sides extend. Antenna device.

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