Antenna device and communication device

Abstract

A second substrate is connected to a first substrate. First antenna elements that emit radio waves in a first direction are disposed on the first substrate. Second antenna elements that emit radio waves in a direction different from the first direction are disposed on the second substrate. Dielectric members are disposed in the region of the surface of the second substrate that includes at least the region in which the second antenna elements are disposed.

Description

[Technical Field]

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

[0002] An antenna device having antenna elements facing in three different directions is known (Patent Document 1). This antenna device includes two rigid substrates and a flexible substrate connecting the two. The flexible substrate is curved to make the surfaces of the two rigid substrates face in different directions. An antenna element is disposed on each of the two rigid substrates, and an antenna element is also disposed on the curved surface of the flexible substrate. This configuration realizes an antenna device with three antenna elements facing in three different directions. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] U.S. Patent Application Publication No. 2020 / 0021015 Summary of the Invention [Problem to be solved by the invention]

[0004] It is desirable to further broaden the bandwidth of antenna devices. An object of the present invention is to provide an antenna device that includes antenna elements facing at least two different directions and that can achieve a broader bandwidth. [Means for solving the problem]

[0005] According to one aspect of the present invention, a first substrate; connected to the first substrate Including curved parts A second substrate; a first antenna element disposed on the first substrate and configured to radiate radio waves in a first direction; a first substrate; a space to which the outer peripheral surface of the curved portion facesa second antenna element for radiating radio waves to the The second antenna element is disposed on the surface of the second substrate in an area including at least the area where the second antenna element is disposed. The surface opposite to the surface facing the second substrate is curved according to the curved shape of the curved portion. A dielectric member An antenna device is provided, comprising:

[0006] According to another aspect of the present invention, the antenna device; a high-frequency integrated circuit that supplies high-frequency signals to the first antenna element and the second antenna element of the antenna device; A communication device is provided, comprising: [Effects of the Invention]

[0007] By disposing the dielectric member, it is possible to broaden the bandwidth of the second antenna element. [Brief explanation of the drawings]

[0008] [Figure 1] 1A and 1B are a perspective view and a cross-sectional view, respectively, of an antenna device according to a first preferred embodiment. [Figure 2] FIG. 2 is a cross-sectional view of an antenna device according to a second embodiment. [Figure 3] FIG. 3 is a cross-sectional view of an antenna device according to a third embodiment. [Figure 4] FIG. 4 is a cross-sectional view of an antenna device according to a fourth preferred embodiment. [Figure 5] FIG. 5 is a cross-sectional view of an antenna device according to a modification of the fourth preferred embodiment. [Figure 6] 6A and 6B are a perspective view and a cross-sectional view, respectively, of an antenna device according to a fifth preferred embodiment of the present invention. [Figure 7] FIG. 7A is a cross-sectional view of an antenna device according to a sixth preferred embodiment, and FIGS. 7B and 7C are cross-sectional views of antenna devices according to modifications of the sixth preferred embodiment. [Figure 8] FIG. 8 is a cross-sectional view of an antenna device according to the seventh preferred embodiment. [Figure 9]FIG. 9 is a block diagram of a communication device according to the eighth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] [First Example] An antenna device according to a first embodiment will be described with reference to FIGS. 1A and 1B. 1A and 1B are a perspective view and a cross-sectional view, respectively, of an antenna device according to a first embodiment. A curved second substrate 21 is connected to a flat first substrate 11. Furthermore, a flat third substrate 31 is connected to the second substrate 21 at a position away from the first substrate 11 in the curvature direction D2 of the second substrate 21. In this specification, a structure in which "substrates are connected" includes both a structure in which separate substrates are connected and a structure in which a single substrate made of the same material is formed continuously.

[0010] The first substrate 11, the second substrate 21, and the third substrate 31 are formed from the same continuous material, and the thickness of the second substrate 21 is thinner than the thicknesses of the first substrate 11 and the third substrate 31. Here, the "thickness of the substrate" refers to the dimension of a substrate having a two-dimensional surface in the direction perpendicular to the two-dimensional surface. Note that the "two-dimensional surface" does not need to be flat and may be curved. The thicknesses of the first substrate 11 and the third substrate 31 are approximately the same. For example, the substrate shown in FIG. 1A is fabricated by thinning the area of a single dielectric substrate corresponding to the second substrate 21 and then curving the thinned second substrate 21. For example, laser processing, router processing, etc. can be used to thin the substrate.

[0011] Of the surfaces of the first substrate 11 and the third substrate 31, the surfaces facing the same space as the outer peripheral surface of the curved portion of the second substrate 21 will be referred to as the first surface 13 and the third surface 33, respectively. The outer peripheral surface of the curved portion of the second substrate 21 will be referred to as the second surface 23. The direction parallel to the intersection line 48 between the imaginary plane including the first surface 13 and the imaginary plane including the third surface 33 will be referred to as the intersection line direction D1.

[0012] A step is formed at the boundary between the first surface 13 and the second surface 23 and at the boundary between the second surface 23 and the third surface 33, making the second surface 23 relatively lower. The opposite surfaces of the first substrate 11, the second substrate 21, and the third substrate 31 are smoothly connected. The step formed at the boundary between the first surface 13 and the second surface 23 can be considered as an end face 15 of the first substrate 11. The step formed at the boundary between the second surface 23 and the third surface 33 can be considered as an end face 35 of the third substrate 31. The end face 15 of the first substrate 11 and the end face 35 of the third substrate 31 extend in a direction parallel to the intersecting direction D1. The first substrate 11 is connected to the second substrate 21 over the entire range of the end face 15 in the intersecting direction D1. Similarly, the third substrate 31 is connected to the second substrate 21 over the entire range of the end face 35 in the intersecting direction D1.

[0013] A plurality of first antenna elements 12 and a plurality of third antenna elements 32 are arranged on the first substrate 11 and the third substrate 31, respectively. The first antenna elements 12 and the third antenna elements 32 radiate radio waves into the space on the same side as the second surface 23 of the second substrate 21. The plurality of first antenna elements 12 are arranged, for example, in a matrix with the row direction parallel to the intersecting direction D1. The plurality of third antenna elements 32 are arranged, for example, in a row parallel to the intersecting direction D1. For example, patch antennas are used as the first antenna elements 12 and the third antenna elements 32.

[0014] A plurality of second antenna elements 22 are arranged on the second substrate 21. The plurality of second antenna elements 22 are arranged in a row parallel to the intersecting direction D1. The second antenna elements 22 radiate radio waves into the space on the second surface 23 side. For example, a dipole antenna is used as the second antenna element 22. The dipole antenna is arranged, for example, in a long orientation in the intersecting direction D1.

[0015] A dielectric member 40 is disposed on the second surface 23 of the second substrate 21, and is in close contact with the second surface 23 of the second substrate 21. The dielectric member 40 is also in close contact with the end faces 15, 35 of the first substrate 11 and the third substrate 31, which are connected to the second surface 23. The surface of the dielectric member 40 opposite to the surface in close contact with the second surface 23 is formed as a curved surface that is curved according to the curved shape of the second surface 23.

[0016] The dielectric member 40 can be formed, for example, by applying a resin precursor to the second surface 23 of the second substrate 21 and then curing the resin precursor. Alternatively, the dielectric member 40 may be formed in advance and then bonded to the second surface 23 with an adhesive.

[0017] A radio frequency integrated circuit (RFIC) 60 is mounted on the surface of the first substrate 11 opposite to the first surface 13. The radio frequency integrated circuit 60 is provided within the first substrate 11 and supplies a radio frequency signal to the first antenna element 12 via a feed line 14 capable of feeding power to the first antenna element 12. Furthermore, the radio frequency integrated circuit 60 supplies a radio frequency signal to the second antenna element 22 via the feed line 14 provided on the first substrate 11 and the feed line 24 provided on the second substrate 21, i.e., the feed lines 14 and 24 capable of feeding power to the second antenna element 22. Furthermore, the radio frequency integrated circuit 60 supplies a radio frequency signal to the third antenna element 32 via the feed line 14 provided on the first substrate 11, the feed line 24 provided on the second substrate 21, and the feed line 34 provided on the third substrate 31, i.e., the feed lines 14 and 24 capable of feeding power to the third antenna element 32.

[0018] In addition to the feeders 14, 24, and 34, a ground plane 16 and the like are also arranged on the first substrate 11 and the third substrate 31. The ground plane 16 is arranged at a position deeper than the first antenna element 12 and the third antenna element 32, with respect to the first surface 13 and the third surface 33, respectively.

[0019] Next, the excellent effects of the first embodiment will be described. In the first embodiment, the first antenna element 12, the second antenna element 22, and the third antenna element 32 face in three different directions in space on the second surface 23 side of the second substrate 21, thereby enabling the coverage of the antenna device to be expanded.

[0020] Furthermore, since the dielectric member 40 is disposed on the second surface 23 of the second substrate 21, the change in the electric field distribution reduces the Q value of the second antenna element 22, resulting in an excellent effect of broadening the bandwidth of the second antenna element 22. Examples of the dielectric member 40 that can be used include sealing resin, adhesive material, substrate material, housing material, tape material, and resist material. Examples of sealing resin include epoxy resin and phenolic resin. Examples of adhesive material include acrylic resin, silicone resin, and polyimide resin. Examples of substrate material include ceramic, liquid crystal polymer, glass epoxy, polytetrafluoroethylene (PTFE), and polyimide resin. Examples of housing material include ABS resin, glass, and acrylic resin. Examples of tape material include polyethylene terephthalate (PET) resin. Examples of resist material include epoxy resin.

[0021] Furthermore, in the first embodiment, the dielectric member 40 is adhered to the second surface 23 of the thinned second substrate 21, thereby increasing the mechanical strength of the second substrate 21. This provides the excellent effect of fixing the curved shape of the second substrate 21 and facilitating the installation work on the housing. Furthermore, because the substrates consisting of the first substrate 11, the second substrate 21, and the third substrate 31 are manufactured from a single substrate, the number of parts can be reduced compared to a method in which these substrates are prepared separately.

[0022] The dielectric member 40 may be adhered to the second substrate 21 either after or before bending the second substrate 21. When employing a procedure for adhering the dielectric member 40 after bending the second substrate 21, it is preferable to apply a liquid or semi-cured resin material to the outer peripheral surface of the curved second substrate 21, and then harden the resin material. When employing a procedure for adhering the dielectric member 40 before bending the second substrate 21, it is preferable to apply a liquid or semi-cured resin material to the surface of the flat second substrate 21, and then harden the resin material.

[0023] Next, a modification of the first embodiment will be described. In the first embodiment, multiple first antenna elements 12, multiple second antenna elements 22, and multiple third antenna elements 32 are arranged, but any one or all of the first antenna element 12, the second antenna element 22, and the third antenna element 32 may be arranged as one.

[0024] In the first embodiment, patch antennas are used as the first antenna element 12 and the third antenna element 32, and a dipole antenna is used as the second antenna element 22, but other antennas may be used. For example, linear antennas such as dipole antennas may be used as the first antenna element 12 and the third antenna element 32. A patch antenna may be used as the second antenna element 22.

[0025] 1A and 1B, the second substrate 21 is bent at a substantially right angle, but the angle of the bend is not limited to a right angle. The angle of the bend can be determined depending on the shape of the housing that houses the antenna device, the characteristics required of the antenna device, and the like.

[0026] In the first embodiment, the dielectric member 40 is disposed so as to cover the entire second surface 23 of the second substrate 21, but in order to broaden the bandwidth of the second antenna element 22, it is not necessarily necessary to dispose the dielectric member 40 over the entire second surface 23. It is sufficient to dispose the dielectric member 40 in an area of the second surface 23 of the second substrate 21 that includes at least the area where the second antenna element 22 is disposed.

[0027] In the first embodiment, the second substrate 21 has a curved shape, but may have other shapes. In this case, the first antenna element 12 arranged on the first substrate 11 radiates radio waves in a first direction, and the second antenna element 22 arranged on the second substrate 21 radiates radio waves in a direction different from the first direction.

[0028] Here, "the first direction in which the first antenna element 12 radiates radio waves" means the direction in which the main beam of the first antenna element 12 faces. "The second antenna element 22 radiates radio waves in a direction different from the first direction" means that the direction in which the main beam of the second antenna element 22 faces is different from the first direction. Here, "the direction in which the main beam faces" does not mean the direction in which the main beam faces when multiple antenna elements operate as an array antenna, but the direction in which the main beam faces when an antenna element operates independently.

[0029] For example, the coverage range of the first antenna element 12 includes the normal direction of the first substrate 11. Furthermore, the coverage range of the second antenna element 22 includes the normal direction of the second substrate 21 at the location where the second antenna element 22 is arranged. Although a portion of the coverage range of the first antenna element 12 and a portion of the coverage range of the second antenna element 22 may overlap with each other, in the sense described above, it can be said that the second antenna element 22 radiates radio waves in a direction different from the first direction in which the first antenna element 12 radiates radio waves.

[0030] [Second Example] Next, an antenna device according to a second embodiment will be described with reference to Fig. 2. Below, a description of the configuration common to the antenna device according to the first embodiment (Figs. 1A and 1B) will be omitted.

[0031] 2 is a cross-sectional view of an antenna device according to a second embodiment. In the antenna device according to the first embodiment (FIGS. 1A and 1B), a dielectric member 40 is disposed on the second surface 23 of the second substrate 21, and the dielectric member 40 is not disposed on the first surface 13 of the first substrate 11 or the third surface 33 of the third substrate 31. In contrast, in the second embodiment, the dielectric member 40 is disposed so as to extend onto the first surface 13 of the first substrate 11 and the third surface 33 of the third substrate 31.

[0032] The dielectric member 40 can be formed, for example, by applying a resin precursor to the first surface 13, the second surface 23, and the third surface 33, and then curing the resin precursor. Alternatively, the dielectric member 40 may be molded in advance and then bonded to the first surface 13, the second surface 23, and the third surface 33 with an adhesive. Alternatively, as shown in FIG. 1B , the dielectric member 40 may be placed only on the second surface 23, and then other dielectric members may be placed on the surface of this dielectric member, the first surface 13, and the third surface 33.

[0033] Next, the excellent effects of the second embodiment will be described. In the second embodiment, as in the first embodiment, the coverage of the antenna device can be expanded. In the antenna device according to the second embodiment, the dielectric member 40 is disposed on the first antenna element 12 and the third antenna element 32, so that the bandwidth of not only the second antenna element 22 but also the first antenna element 12 and the third antenna element 32 can be broadened. Furthermore, the mechanical strength of the entire antenna device can be increased. Also, an adhesive can be used as the dielectric member 40, and the antenna device can be bonded to the inner surface of the housing using this adhesive.

[0034] [Third Example] Next, an antenna device according to a third embodiment will be described with reference to Fig. 3. Below, a description of the configuration common to the antenna device according to the second embodiment (Fig. 2) will be omitted.

[0035] 3 is a cross-sectional view of an antenna device according to a third embodiment. In the second embodiment (FIG. 2), steps are formed at the boundary between the first surface 13 and the second surface 23 and at the boundary between the second surface 23 and the third surface 33. In contrast, in the third embodiment, the first surface 13, the second surface 23, and the third surface 33 are smoothly connected. Instead, steps are formed on the opposite surfaces of the first substrate 11, the second substrate 21, and the third substrate 31. As in the second embodiment, the dielectric member 40 is disposed on the first surface 13, the second surface 23, and the third surface 33.

[0036] Next, the excellent effects of the third embodiment will be described. In the third embodiment, as in the second embodiment, it is possible to expand the coverage of the antenna device, broaden the bandwidth of the antenna device, and improve the mechanical strength of the antenna device. Furthermore, in the third embodiment, the base surface of the dielectric member 40 is smooth, which has the excellent effect of making it easy to mold the dielectric member 40.

[0037] Next, a modification of the third embodiment will be described. In the third embodiment, the dielectric member 40 is disposed on the first surface 13, the second surface 23, and the third surface 33, but another dielectric member may also be disposed on the surface of the second substrate 21 opposite the second surface 23. This configuration provides the excellent effect of further increasing the mechanical strength. Alternatively, the dielectric member 40 may not be disposed on the first surface 13, the second surface 23, and the third surface 33, and a dielectric member may be adhered only to the surface of the second substrate 21 opposite the second surface 23. In this case as well, the excellent effect of increasing the mechanical strength is obtained.

[0038] [Fourth Example] Next, an antenna device according to a fourth embodiment will be described with reference to Fig. 4. Below, a description of the configuration common to the antenna device according to the first embodiment (Figs. 1A and 1B) will be omitted.

[0039] FIG. 4 is a cross-sectional view of an antenna device according to a fourth embodiment. In the antenna device according to the first embodiment (FIGS. 1A and 1B), the first substrate 11, the second substrate 21, and the third substrate 31 are formed of the same continuous material. In contrast, in the fourth embodiment, flat rigid substrates are used for the first substrate 11 and the third substrate 31, and a flexible substrate is used for the second substrate 21. Examples of rigid substrates include glass epoxy substrates, low-temperature co-fired ceramic (LTCC) substrates, and liquid crystal polymer substrates. Examples of flexible substrates include polyimide substrates, PET substrates, and liquid crystal polymer substrates. Liquid crystal polymer substrates can be used as either rigid or flexible substrates depending on their thickness.

[0040] The second substrate 21 is connected to the surface of the first substrate 11 opposite to the first surface 13 via a connecting member 46 such as a connector or solder, and the second substrate 21 is connected to the surface of the third substrate 31 opposite to the third surface 33 via a connecting member 46 such as solder. The power feed line 14 in the first substrate 11 and the power feed line 24 in the second substrate 21 are electrically connected via the connecting member 46, and the power feed line 24 in the second substrate 21 and the power feed line 34 in the third substrate 31 are electrically connected via the connecting member 46.

[0041] A dielectric member 40 is disposed on the second surface 23, which is the outer peripheral surface of the curved portion of the second substrate 21. The dielectric member 40 is in close contact with the second surface 23 of the second substrate 21 and the end faces 15, 35 of the first substrate 11 and the third substrate 31.

[0042] Next, the excellent effects of the fourth embodiment will be described. In the fourth embodiment, as in the first embodiment, it is possible to expand the coverage of the antenna device, widen the bandwidth of the second antenna element 22, and improve the mechanical strength.

[0043] Next, an antenna device according to a modification of the fourth embodiment will be described with reference to FIG. Fig. 5 is a cross-sectional view of an antenna device according to a modification of the fourth embodiment. In the antenna device according to the fourth embodiment (Fig. 4), the dielectric member 40 is in close contact with the entire second surface 23 of the second substrate 21. In contrast, in the modification shown in Fig. 5, the dielectric member 40 is in close contact with only a partial area of the second surface 23. More specifically, the dielectric member 40 is disposed on an area of the second surface 23 that includes the second antenna element 22. Gaps are secured between the dielectric member 40 and the first substrate 11, and between the dielectric member 40 and the third substrate 31.

[0044] Such a structure can be produced, for example, by adhering the dielectric member 40, which has been formed into a predetermined shape, to the second substrate 21 with an adhesive member such as adhesive or double-sided tape.

[0045] 5, it is also possible to broaden the bandwidth of the second antenna element 22. Furthermore, the mechanical strength of a portion of the second substrate 21 can be increased.

[0046] Next, another modification of the fourth embodiment will be described. In the fourth embodiment, solder is used as the connection member 46. Alternatively, a connector may be used as the connection member 46.

[0047] [Fifth Example] Next, an antenna device according to a fifth embodiment will be described with reference to Figures 6A and 6B. Below, a description of the configuration common to the antenna device according to the first embodiment (Figures 1A and 1B) will be omitted.

[0048] 6A and 6B are a perspective view and a cross-sectional view, respectively, of an antenna device according to the fifth embodiment. As in the first embodiment (FIGS. 1A and 1B), the direction parallel to the intersection line 48 between an imaginary plane including the first surface 13 of the first substrate 11 and an imaginary plane including the third surface 33 of the third substrate 31 is referred to as the intersection direction D1.

[0049] In the first embodiment (FIG. 1A), the first substrate 11 and the third substrate 31 are connected to the second substrate 21 over the entire range in the intersecting direction D1. In contrast, in the fifth embodiment, the third substrate 31 is connected to the second substrate 21 at an end surface 35 over only a portion of the range in the intersecting direction D1. The end surfaces 35 connected to the second substrate 21 are arranged at multiple locations spaced apart in the intersecting direction D1.

[0050] The third substrate 31 has a plurality of protrusions 31P that protrude further than the end face 35 toward the intersection line 48 in a range not connected to the second substrate 21 in the intersection direction D1. The third surface 33 of the protrusions 31P is located in the same imaginary plane as the third surface 33 at locations other than the protrusions 31P. Such a substrate structure can be fabricated using, for example, the method described in the specification of WO 2020 / 170722.

[0051] The plurality of third antenna elements 32 are arranged in a range in which the protruding portion 31P is provided with respect to the intersecting direction D1. At least a portion of each of the plurality of third antenna elements 32 is arranged on the protruding portion 31P.

[0052] The second antenna element 22 is disposed on the second substrate 21 between two adjacent protrusions 31P in the intersecting direction D1. The dielectric member 40 is disposed on the second surface 23 of the second substrate 21 between two adjacent protrusions 31P in the intersecting direction D1. In Fig. 6A, the dielectric member 40 is indicated by a dashed line.

[0053] Next, the excellent effects of the fifth embodiment will be described. As in the first embodiment, the fifth embodiment can also expand the coverage of the antenna device, broaden the bandwidth of second antenna element 22, and improve the mechanical strength. Furthermore, by providing protrusion 31P on third substrate 31 and locating a portion of third antenna element 32 on protrusion 31P, the dimensions of the antenna device in the direction perpendicular to first surface 13 can be reduced.

[0054] [Sixth Example] Next, an antenna device according to a sixth embodiment will be described with reference to Fig. 7A. Below, a description of the configuration common to the antenna device according to the first embodiment (Figs. 1A and 1B) will be omitted.

[0055] 7A is a cross-sectional view of an antenna device according to a sixth embodiment. In the antenna device according to the first embodiment, a third substrate 31 is connected to a second substrate 21 at a distance from the first substrate 11 in the curved direction D2. In contrast, in the sixth embodiment, the third substrate 31 is not connected to the second substrate 21, and instead the second substrate 21 has a shape that is longer in the curved direction D2 than the second substrate 21 of the first embodiment. The second substrate 21 is connected to the first substrate 11 via a connecting member 46, similar to the antenna device according to the fourth embodiment (FIG. 4). A flexible substrate is used as the second substrate 21.

[0056] The second substrate 21 includes a curved portion 21A connected to the first substrate 11 and a flat portion 21B continuous with the curved portion 21A. The flat portion 21B is connected to the first substrate 11 via the curved portion 21A. A second antenna element 22A is arranged on the curved portion 21A, and another second antenna element 22B is arranged on the flat portion 21B. A dielectric member 40 is in close contact with a second surface 23A on the outer periphery of the curved portion 21A and a second surface 23B of the flat portion 21B continuous therewith.

[0057] A high-frequency integrated circuit 60 is mounted on the surface of the first substrate 11 opposite to the first surface 13. The second antenna elements 22A and 22B are connected to the high-frequency integrated circuit 60 via a feeder line 24 and a connecting member 46 arranged on the second substrate 21, and a feeder line 14 arranged on the first substrate 11.

[0058] Next, the excellent effects of the sixth embodiment will be described. In the sixth embodiment, as in the first embodiment, it is possible to expand the coverage of the antenna device, widen the bandwidth of the second antenna elements 22A and 22B, and improve the mechanical strength. Furthermore, in the sixth embodiment, the flat portion 21B of the second substrate 21, which is a flexible substrate, is used instead of the flat third substrate 31 of the first embodiment (FIGS. 1A and 1B). This makes it possible to flexibly adapt to the shape of the space inside the housing.

[0059] Next, an antenna device according to a modified example of the sixth embodiment will be described with reference to Figures 7B and 7C. In the sixth embodiment (Figure 7A), second antenna elements 22A and 22B are arranged on curved portion 21A and flat portion 21B of second substrate 21, respectively.

[0060] 7B, the second antenna element 22A is disposed on the curved portion 21A of the second substrate 21, but no antenna element is disposed on the flat portion 21B. The dielectric member 40 is in close contact with the area of the second surface 23A that includes the second antenna element 22A, but no dielectric member is disposed on the second surface 23B of the flat portion 21B. The dielectric member 40 is also in close contact with the end surface 15 of the first substrate 11. In this modification, the bandwidth of the second antenna element 22A disposed on the curved portion 21A of the second substrate 21 can be broadened.

[0061] 7C , on the other hand, second antenna element 22B is arranged on flat portion 21B of second substrate 21, but no antenna element is arranged on curved portion 21A. Dielectric member 40 is in close contact with the area of second surface 23A that includes second antenna element 22B, but no dielectric member is arranged on second surface 23A of curved portion 21A. In this modification, the bandwidth of second antenna element 22A arranged on flat portion 21B of second substrate 21 can be broadened.

[0062] As in the modified example of the sixth embodiment shown in Figures 7B and 7C, the second antenna element 22A may be arranged only on the curved portion 21A of the second substrate 21, or the second antenna element 22B may be arranged only on the flat portion 21B.

[0063] [Seventh Example] Next, an antenna device according to a seventh embodiment will be described with reference to Fig. 8. Below, a description of the configuration common to the antenna device according to the first embodiment (Figs. 1A and 1B) will be omitted.

[0064] 8 is a cross-sectional view of an antenna device according to a seventh embodiment. The configurations of the first substrate 11, the second substrate 21, the third substrate 31, the first antenna element 12, the second antenna element 22, the third antenna element 32, and the dielectric member 40 are the same as those of the antenna device according to the first embodiment (FIGS. 1A and 1B). In the seventh embodiment, the first substrate 11, the first antenna element 12, etc. are housed in a housing 50.

[0065] The inner surface of the housing 50 includes a first region 56A and a second region 56B connected via a straight corner 55 formed by the intersection of two planes. The corner 55 does not necessarily have to be a sharp corner formed by the intersection of two planes. For example, the first region 56A and the second region 56B may be connected via a curved surface having a certain curvature, or may be connected via a plane oblique to both the first region 56A and the second region 56B. The first surface 13 of the first substrate 11 and the third surface 33 of the third substrate 31 are bonded to the first region 56A and the second region 56B of the housing 50, respectively, with adhesive layers 45 such as adhesive or double-sided tape. The first antenna element 12 faces the first region 56A, and the third antenna element 32 faces the second region 56B.

[0066] The housing 50 includes a first transparent window 51, a second transparent window 52, and a third transparent window 53, and a metal wall 54 surrounding these transparent windows. When the first region 56A is viewed from above, the first transparent window 51 encloses the first antenna element 12, and when the second region 56B is viewed from above, the third transparent window 53 encloses the third antenna element 32. Radio waves radiated from the first antenna element 12 and the third antenna element 32 pass through the first transparent window 51 and the third transparent window 53, respectively, and are radiated to the outside of the housing 50.

[0067] The second transparent window 52 is disposed in the corner portion 55. The first substrate 11, the second substrate 21, and the third substrate 31 are housed in the housing 50, with at least a portion of the second substrate 21 spaced apart from the inner surface of the housing 50. More specifically, the second surface 23, which is the surface on the outer periphery of the curved portion of the second substrate 21, faces the inner surface of the corner portion 55 via the dielectric member 40, with the second surface 23 spaced apart from the inner surface of the housing 50. The radio waves radiated from the second antenna element 22 pass through the dielectric member 40 and the second transparent window 52 and are radiated to the outside of the housing 50.

[0068] The first antenna element 12, the second antenna element 22, and the third antenna element 32 act as primary wave sources, and the first transmission window 51, the second transmission window 52, and the third transmission window 53 act as secondary wave sources for the first antenna element 12, the second antenna element 22, and the third antenna element 32, respectively. In other words, each point on the outer surface of the first transmission window 51, the second transmission window 52, and the third transmission window 53 acts as a wave source of a secondary wave based on the Huygens-Fresnel principle.

[0069] Next, the excellent effects of the seventh embodiment will be described. The dielectric member 40 is in close contact with the second substrate 21, thereby achieving a broadband of the second antenna element 22. Furthermore, the shape of the second substrate 21 is stable, which has the excellent effect of facilitating the work of attaching the first substrate 11, the second substrate 21, and the third substrate 31 to the housing 50.

[0070] In a configuration that does not have the second antenna element 22 and the second transmission window 52, the distance G3 between the first transmission window 51 and the third transmission window 53 corresponds to the distance between the secondary wave sources. In contrast, in the antenna device according to the seventh embodiment, the distance G1 between the second transmission window 52 provided at the corner 55 and the first transmission window 51, and the distance G2 between the second transmission window 52 and the third transmission window 53 correspond to the distance between the secondary wave sources. By providing the second transmission window 52 at the corner 55 and arranging the second antenna element 22 facing it, the distance between the secondary wave sources is narrowed. Therefore, when the first antenna element 12, the second antenna element 22, and the third antenna element 32 are operated as an array antenna, side lobes and grating lobes can be suppressed.

[0071] It is preferable that the spacings G1 and G2 be less than the free space wavelength corresponding to the lowest frequency in the operating frequency band of the first antenna element 12, the second antenna element 22, and the third antenna element 32. This configuration makes it possible to suppress side lobes and grating lobes near the lowest frequency in the operating frequency band. It is even more preferable that the spacings G1 and G2 be less than the free space wavelength corresponding to the highest frequency in the operating frequency band. This configuration makes it possible to suppress side lobes and grating lobes over almost the entire operating frequency band.

[0072] [Eighth Example] Next, a communication device according to an eighth embodiment will be described with reference to Fig. 9. The communication device according to the eighth embodiment includes an antenna device according to any one of the first to seventh embodiments or a modification thereof.

[0073] FIG. 9 is a block diagram of a communication device according to the eighth embodiment. The communication device according to the eighth embodiment includes a baseband integrated circuit (BBIC) 80, a radio frequency integrated circuit (RFIC) 60, and an antenna device 57. The antenna device 57 may be an antenna device according to any one of the first to seventh embodiments or a modification thereof. The antenna device 57 includes a plurality of antenna elements 58. The plurality of antenna elements 58 may include, for example, the first antenna element 12, the second antenna element 22, the third antenna element 32, etc., of the first embodiment ( FIG. 1A ).

[0074] The baseband integrated circuit 80 and the high-frequency integrated circuit 60 are housed in a housing 50 (FIG. 8) that is common to the housing 50 of the antenna device 57. For example, the high-frequency integrated circuit 60 is mounted on the first substrate 11 of the antenna device (FIG. 6) according to the sixth embodiment shown in FIG.

[0075] The high-frequency integrated circuit 60 includes an intermediate frequency amplifier 61, an up / down conversion mixer 62, a transmit / receive switch 63, a power divider 64, a plurality of phase shifters 65, a plurality of attenuators 66, a plurality of transmit / receive switches 67, a plurality of power amplifiers 68, a plurality of low-noise amplifiers 69, and a plurality of transmit / receive switches 70.

[0076] First, the transmission function will be described. An intermediate frequency signal is input from the baseband integrated circuit 80 to the up / down conversion mixer 62 via the intermediate frequency amplifier 61. The up / down conversion mixer 62 upconverts the intermediate frequency signal to generate a high frequency signal. The generated high frequency signal is input to the power divider 64 via the transmit / receive switch 63. Each of the high frequency signals divided by the power divider 64 is input to the antenna element 58 via the phase shifter 65, the attenuator 66, the transmit / receive switch 67, the power amplifier 68, and the transmit / receive switch 70.

[0077] Next, the receiving function will be described. High-frequency signals received by each of the multiple antenna elements 58 are input to a power divider 64 via a transmit / receive switch 70, a low-noise amplifier 69, a transmit / receive switch 67, an attenuator 66, and a phase shifter 65. The high-frequency signal combined by the power divider 64 is input to an up / down conversion mixer 62 via a transmit / receive switch 63. The up / down conversion mixer 62 down-converts the high-frequency signal to generate an intermediate-frequency signal. The generated intermediate-frequency signal is input to a baseband integrated circuit 80 via an intermediate-frequency amplifier 61. Note that a direct conversion system in which the up / down conversion mixer 62 directly down-converts the high-frequency signal to a baseband signal may also be employed.

[0078] Next, the excellent effects of the eighth embodiment will be described. As the antenna device 57 included in the communication device according to the eighth embodiment, an antenna device according to any one of the first to seventh embodiments or a modified version thereof is used, thereby making it possible to achieve a wider bandwidth and expand the range of beamforming.

[0079] The above-described embodiments are merely examples, and it goes without saying that partial substitution or combination of the configurations shown in different embodiments is possible. Similar effects resulting from similar configurations of multiple embodiments will not be mentioned sequentially for each embodiment. Furthermore, the present invention is not limited to the above-described embodiments. For example, it will be obvious to those skilled in the art that various modifications, improvements, combinations, etc. are possible. [Explanation of symbols]

[0080] 11 First board 12 First antenna element 13 1st surface 14 Power line 15 End face of first substrate 16 Ground Plane 21 Second board 21A Curved portion of second board 21B Flat portion of second substrate 22 Second antenna element 22A Second antenna element at curved section 22B Second antenna element on flat section 23 Second surface (surface on the outer periphery of the curved portion) 23A: Second surface of curved portion of second substrate 23B Second surface of flat portion of second substrate 24 Feed line 31 Third board 31P protrusion 32 Third antenna element 33 Third surface 34 Feed line 35 End face of third substrate 40 Dielectric material 45 Adhesive layer 46 Connecting member 48 Intersection line between an imaginary plane including the first surface and an imaginary plane including the third surface 50 cabinets 51 First transparent window 52 Second transparent window 53 Third transparent window 54 metal wall 55 Corner 56A First area of the inner surface of the housing 56B Second area of the inner surface of the housing 57 Antenna equipment 58 Antenna Elements 60 Radio Frequency Integrated Circuits (RFIC) 61 Intermediate frequency amplifier 62 Up / down conversion mixer 63 Transmit / Receive Switch 64 Power Divider 65 Phase shifter 66 Attenuator 67 Transmit / Receive Switch 68 Power Amplifier 69 Low Noise Amplifier 70 Transmit / Receive Switch 80 Baseband Integrated Circuit

Claims

1. a first substrate; a second substrate including a curved portion connected to the first substrate; a first antenna element disposed on the first substrate and configured to radiate radio waves in a first direction; a second antenna element disposed on the second substrate and configured to radiate radio waves in a direction different from the first direction toward a space to which an outer peripheral surface of the curved portion faces; a dielectric member that is disposed in an area of the surface of the second substrate that includes at least an area in which the second antenna element is disposed, and whose surface opposite to the surface facing the second substrate is curved according to the curved shape of the curved portion; An antenna device comprising:

2. a third substrate connected to the second substrate; a third antenna element disposed on the third substrate and configured to radiate radio waves in a direction different from the first direction; The antenna device of claim 1 further comprising:

3. 3. The antenna device according to claim 1, wherein the first substrate and the second substrate are formed continuously, and the second substrate is thinner than the first substrate.

4. 3. The antenna device according to claim 1, wherein the first substrate and the second substrate are made of the same material, and the second substrate is thinner than the first substrate.

5. the first substrate is a rigid substrate, 3. The antenna device according to claim 1, wherein the second substrate is a flexible substrate.

6. A power feeder capable of feeding power to the second antenna element is arranged on each of the first substrate and the second substrate, and the power feeder of the first substrate and the power feeder of the second substrate are connected via a connecting member.

6. The antenna device according to claim 5, wherein the antenna is connected to the ground.

7. A first substrate; a second substrate connected to the first substrate; a first antenna element disposed on the first substrate and configured to radiate radio waves in a first direction; a second antenna element disposed on the second substrate and configured to radiate radio waves in a direction different from the first direction; a dielectric member disposed on a surface of the second substrate in an area including at least an area in which the second antenna element is disposed; Equipped with The antenna device is configured such that the dielectric member extends onto the surface of the first substrate.

8. the first substrate and the third substrate have end faces extending in a direction parallel to an intersection line between an imaginary plane including a flat surface of the first substrate and an imaginary plane including a flat surface of the third substrate, the third substrate is connected to the second substrate at an end surface extending in the intersecting line direction within a partial range in the intersecting line direction, the third substrate includes a protruding portion that protrudes beyond an end surface connected to the second substrate in a range other than a range connected to the second substrate in the direction of the intersection line, The antenna device according to claim 2 , wherein at least a portion of the third antenna element is disposed on the protruding portion.

9. A first substrate; a second substrate connected to the first substrate; a first antenna element disposed on the first substrate and configured to radiate radio waves in a first direction; a second antenna element disposed on the second substrate and configured to radiate radio waves in a direction different from the first direction; a dielectric member disposed on a surface of the second substrate in an area including at least an area in which the second antenna element is disposed; a housing that houses the first substrate and the second substrate; Equipped with the first substrate and the second substrate are housed in the housing with at least a portion of the second substrate spaced apart from the inner surface of the housing; The housing includes: a first transmission window through which radio waves radiated from the first antenna element can pass; a second transmission window through which radio waves radiated from the second antenna element can pass; Including, An antenna device in which the distance between the first and second transmission windows at their closest points is less than a free space wavelength corresponding to the lowest frequency in the operating frequency band of the first antenna element and the second antenna element.

10. the second substrate further includes a flat portion connected to the curved portion; 3. The antenna device according to claim 1, wherein a plurality of the second antenna elements are arranged on the second substrate, and the second antenna elements are arranged on each of the curved portion and the flat portion.

11. the second substrate further includes a flat portion connected to the curved portion, The antenna device according to claim 1 , wherein the second antenna element is disposed on one of the curved portion and the flat portion.

12. An antenna device as described in claim 1 or 2, wherein the first surface of the first substrate, which is the surface facing the space on the same side as the outer peripheral surface of the curved portion, and the second surface, which is the surface on the outer peripheral side of the curved portion, have an end surface of the first substrate that forms a step at the boundary between the first surface and the second surface such that the second surface is relatively lower, and the dielectric member is in close contact with the end surface of the first substrate.

13. The antenna device according to claim 1 or 2; a high-frequency integrated circuit that supplies high-frequency signals to the first antenna element and the second antenna element of the antenna device; A communication device comprising:

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