Antenna device and communication device equipped with same

Abstract

Provided are: an antenna device which can be miniaturized even when two types of antennas are combined, and which can suppress a decrease in radiation gain; and a communication device equipped with the antenna device. An antenna device (100) is provided with a dielectric substrate (130), a power feed element (121), a grounding electrode (GND), and peripheral electrodes (150a to 150d). The power feed element (121) radiates radio waves in a first polarization direction. The grounding electrode (GND) is disposed opposing the power feed element (121). The peripheral electrodes (150a to 150d) are formed in a plurality of layers between the power feed element (121) and the grounding electrode (GND), and are electrically connected to the grounding electrode (GND). The peripheral electrodes (150a to 150d) are disposed in positions that are symmetrical with respect to at least one of a first direction parallel to the first polarization direction and a second direction orthogonal to the first polarization direction. At least one of the peripheral electrodes (150a to 150d) constitutes a horn antenna.

Description

Antenna device and communication device equipped with same

[0001] The present disclosure relates to an antenna device and a communication device equipped with the same.

[0002] U.S. Patent Application Publication No. 2023 / 0114757 (Patent Document 1) discloses an antenna device that combines a planar antenna in which multiple flat radiating elements (patch antennas) are formed on a rectangular substrate with a side-emitting antenna of a waveguide antenna.

[0003] US Patent Application Publication No. 2023 / 0114757

[0004] The antenna device disclosed in U.S. Patent Application Publication No. 2023 / 0114757 (Patent Document 1) is configured by combining two types of antennas independently, resulting in a large board size. The large board size makes it difficult to use the antenna device in mobile terminals such as mobile phones or smartphones, which have strict requirements for miniaturization and thinness. Furthermore, the large board size may reduce the radiation gain of the planar antenna.

[0005] The present disclosure has been made to solve such problems, and its purpose is to provide an antenna device that can be miniaturized even when two types of antennas are combined, and that can suppress a decrease in radiation gain, and a communication device equipped with the same.

[0006] The antenna device according to the present disclosure includes a dielectric substrate having a plurality of dielectric layers laminated thereon, a radiating element formed on the dielectric substrate and radiating radio waves in a first polarization direction, a ground electrode disposed opposite the radiating element, and a peripheral electrode formed on a plurality of layers between the radiating element and the ground electrode and electrically connected to the ground electrode. The peripheral electrode is disposed symmetrically with respect to at least one of a first direction parallel to the first polarization direction and a second direction orthogonal to the first polarization direction, and the disposed at least one peripheral electrode constitutes a horn antenna.

[0007] According to the antenna device of the present disclosure, at least one peripheral electrode arranged symmetrically with respect to at least one of a first direction parallel to the polarization direction of the radiating element and a second direction orthogonal to the first direction constitutes a horn antenna. By arranging the peripheral electrode symmetrically with respect to the radiating element in this way, the electric field lines generated in the radiating element are made uniform, thereby suppressing a decrease in radiation gain. By configuring the peripheral electrode as a horn antenna, it is possible to add different types of antennas while miniaturizing the device.

[0008] 1 is a perspective view of an antenna device according to a first embodiment. FIG. 2 is a block diagram of a communication device including the antenna device. FIG. 3 is a plan view of the antenna device according to the first embodiment. FIG. 4 is a diagram illustrating the antenna gain of the antenna device according to the first embodiment. FIG. 5 is a perspective view of an antenna device according to a second embodiment. FIG. 6 is a side perspective view of the antenna device of FIG. 5. FIG. 7 is a diagram illustrating an example of the shape of a horn antenna. FIG. 8 is a diagram illustrating an example of a wall portion of a horn antenna. FIG. 9 is a perspective view of an antenna device according to a third embodiment. FIG. 10 is a perspective view of an antenna device according to a modification of the third embodiment. FIG. 11 is a perspective view of an antenna device according to a fourth embodiment. FIG. 12 is a perspective view of an antenna device according to a first modification of the fourth embodiment. FIG. 13 is a perspective view of an antenna device according to a second modification of the fourth embodiment.

[0009] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are designated by the same reference numerals, and description thereof will not be repeated.

[0010] [First Embodiment] Fig. 1 is a perspective view of antenna device 100 according to the first embodiment. Fig. 2 is a block diagram of communication device 300 including antenna device 100. Fig. 3 is a plan view of antenna device 100 according to the first embodiment. Communication device 300 to which antenna device 100 according to the first embodiment is applied is, for example, a mobile terminal such as a mobile phone, a smartphone, or a tablet, or a personal computer with a communication function. An example of the frequency band of radio waves used in antenna device 100 according to the present embodiment is millimeter-wave radio waves with center frequencies of 28 GHz, 39 GHz, and 60 GHz, but radio waves in other frequency bands are also applicable.

[0011] 2 , the communication device 300 includes the antenna device 100, an RFIC 110 which is an example of a power supply circuit, and a BBIC 200 which constitutes a baseband signal processing circuit. The RFIC 110 and the antenna device 100 constitute an antenna module. The communication device 300 upconverts a signal transmitted from the BBIC 200 to the antenna device 100 in the RFIC 110 to a high-frequency signal and radiates the signal from the antenna device 100. The communication device 300 also transmits a high-frequency signal received by the antenna device 100 to the RFIC 110, downconverts the signal, and processes it in the BBIC 200.

[0012] 1, for ease of explanation, one feed element 121 (radiating element) constituting the antenna device 100 is shown. Note that the antenna device 100 may be a one-dimensional array antenna in which a plurality of feed elements 121 are arranged in a line, or a two-dimensional array antenna in which a plurality of feed elements 121 are arranged in a two-dimensional array. In this embodiment, the feed element 121 is a patch antenna having a flat plate shape.

[0013] Next, the configuration of the antenna device 100 according to the first embodiment will be described in detail with reference to Figures 1 and 3. The antenna device 100 includes a feed element 121, a dielectric substrate 130, a feed wiring 140, peripheral electrodes 150a to 150d, and a ground electrode GND. In the following description, the normal direction of the dielectric substrate 130 (the main radiation direction of the patch antenna) is defined as the Z-axis direction, and planes perpendicular to the Z-axis direction are defined as the X-axis and the Y-axis. In each figure, the positive direction of the Z-axis may be referred to as the upper side, and the negative direction may be referred to as the lower side.

[0014] The dielectric substrate 130 is, for example, a low temperature co-fired ceramics (LTCC) multilayer substrate, a multilayer resin substrate formed by stacking multiple resin layers made of resin such as epoxy or polyimide, a multilayer resin substrate formed by stacking multiple resin layers made of liquid crystal polymer (LCP) having a lower dielectric constant, a multilayer resin substrate formed by stacking multiple resin layers made of fluorine-based resin, or a ceramic multilayer substrate other than LTCC.

[0015] The dielectric substrate 130 has a substantially rectangular shape, and the feeding element 121 is disposed on a layer (upper layer) close to its top surface 131 (the surface in the positive direction of the Z axis). The feeding element 121 may be exposed on the surface of the dielectric substrate 130, or may be disposed on an internal layer of the dielectric substrate 130 as in the example of FIG. 1.

[0016] A flat ground electrode GND is arranged facing the feed element 121 on a layer (lower layer) of the dielectric substrate 130 that is closer to the bottom surface 132 (the surface in the negative direction of the Z axis) than the feed element 121. A high-frequency signal is supplied to a feed point (not shown) of the feed element 121 from the RFIC 110 via a feed wiring 140 (first feed wiring). The feed wiring 140 rises from directly below the feed element 121, penetrates the ground electrode GND, and is connected to the feed point of the feed element 121. Note that radio waves are radiated with a polarization direction perpendicular to each side of the rectangular feed element 121 (the direction of the dashed line CL in FIG. 3 ).

[0017] Peripheral electrodes 150a to 150d are formed on multiple dielectric layers between feed element 121 and ground electrode GND at the end of dielectric substrate 130. In antenna device 100, peripheral electrodes 150a to 150d are arranged at positions corresponding to each side of rectangular feed element 121 when viewed in a plan view from the normal direction of dielectric substrate 130 (positive direction of the Z axis). Peripheral electrodes 150a to 150d arranged at positions corresponding to each side are arranged symmetrically with respect to the polarization direction of feed element 121 (the direction of dashed line CL in FIG. 3 ) and the direction perpendicular to the polarization direction.

[0018] The peripheral electrodes 150a to 150d are stacked in the normal direction of the dielectric substrate 130. Therefore, the peripheral electrodes 150a to 150d form conductor walls along each side of the feed element 121. Adjacent electrodes of the peripheral electrodes 150a to 150d in the stacking direction are electrically connected to each other by multiple via conductors or plate-shaped conductors. Furthermore, the electrode located in the bottom layer of the peripheral electrodes 150a to 150d is electrically connected to the ground electrode GND. In other words, the peripheral electrodes 150a to 150d are essentially configured equivalently to a configuration in which the end of the ground electrode GND is extended in the stacking direction.

[0019] In a patch antenna having such a flat-plate-shaped feed element 121, radio waves are radiated by electromagnetic field coupling between the feed element 121 and the ground electrode GND. To achieve a desired radiation gain, it is necessary to arrange a ground electrode GND having a sufficiently large area relative to the feed element 121.

[0020] However, when the antenna device is placed in a limited space inside the housing, such as in a mobile terminal, it may not be possible to make the ground electrode GND sufficiently wide relative to the feed element 121. If the area of ​​the ground electrode GND is not sufficient, some of the electric field lines from the feed element 121 may wrap around the back surface of the ground electrode GND. This may increase the proportion of radio waves radiated to the back surface of the antenna device, disrupting the directivity and potentially degrading the antenna gain in the desired direction, narrowing the frequency bandwidth, or causing fluctuations in the polarization direction, such as circular polarization.

[0021] Therefore, in the antenna device 100 of the first embodiment, as shown in FIGS. 1 and 3, peripheral electrodes 150a to 150d electrically connected to the ground electrode GND are arranged in a layer between the feed element 121 and the ground electrode GND. Because the distance between the peripheral electrodes 150a to 150d and the feed element 121 is shorter than the distance between the ground electrode GND and the feed element 121, the degree of electromagnetic coupling between the feed element 121 and the peripheral electrodes 150a to 150d is stronger than that between the feed element 121 and the ground electrode GND. As a result, some of the electric field lines from the feed element 121 do not wrap around to the back side of the ground electrode GND, but are generated between the peripheral electrodes 150a to 150d. This suppresses radio wave radiation to the back side of the antenna device 100, thereby suppressing a decrease in radiation gain, such as gain.

[0022] The peripheral electrodes 150a to 150d are arranged symmetrically with respect to the polarization direction of the radio wave and / or the direction perpendicular to the polarization direction, which improves the symmetry of the electric field lines generated between the feed element 121 and the ground electrode GND, thereby suppressing fluctuations in the polarization direction.

[0023] Furthermore, in the antenna device 100 of the first embodiment, the peripheral electrode 150a forms a horn antenna. The antenna device 100 does not simply combine two types of antennas, a patch antenna and a horn antenna, on the dielectric substrate 130, but rather forms a horn antenna using the peripheral electrode 150a of the patch antenna including the feed element 121. Therefore, the antenna device 100 can be made smaller than when two types of antennas are simply combined. Furthermore, in the antenna device 100, the peripheral electrode 150a, which is a horn antenna, prevents radio waves from being emitted to the back side, thereby suppressing a decrease in radiation gain, such as gain.

[0024] The peripheral electrode 150a includes a waveguide 151a formed in a cylindrical shape by electrodes formed in multiple layers, and a horn portion 152a connected to the waveguide 151a and formed in a cone shape by electrodes formed in multiple layers. The horn antenna of the peripheral electrode 150a has a via conductor provided in the waveguide 151a (not shown), and power is supplied from the RFIC 110 to the via conductor via a power supply wiring 141 (second power supply wiring) electrically connected to the via conductor, and a high-frequency signal is supplied in this order to the waveguide 151a and the horn portion 152a. Note that a via conductor need not be provided in the waveguide 151a as long as a high-frequency signal can be supplied to the waveguide 151a.

[0025] The horn antenna of peripheral electrode 150a radiates radio waves from the opening of horn portion 152a. The opening of horn portion 152a is located on the X-axis-Z-axis plane of dielectric substrate 130 and faces the positive direction of the Y-axis. Therefore, the horn antenna of peripheral electrode 150a has a main radiation direction in the positive direction of the Y-axis, which is different from the main radiation direction of the patch antenna including feed element 121, whose main radiation direction is the positive direction of the Z-axis.

[0026] As shown in FIG. 1 , the opening of horn portion 152a is longer than waveguide 151a in the horizontal direction of dielectric substrate 130. That is, horn portion 152a has a cone shape that widens in the horizontal direction of dielectric substrate 130 as it progresses in the positive direction of the Y axis. This increases the radiation gain of the horn antenna of peripheral electrode 150a. Note that the horn antenna of peripheral electrode 150a may include multiple dielectric layers of dielectric substrate 130 inside waveguide 151a and horn portion 152a, or may have a gap where multiple dielectric layers of dielectric substrate 130 have been removed.

[0027] In antenna device 100 according to the first embodiment, not only can radio waves be radiated in the normal direction (Z-axis direction) of dielectric substrate 130 by the patch antenna including feed element 121, but also in the horizontal direction (Y-axis direction) of dielectric substrate 130 by the horn antenna of peripheral electrode 150a. Fig. 4 is a diagram showing the antenna gain of antenna device 100 according to the first embodiment. The antenna gain shown in Fig. 4 is shown as the peak gain at each angle from the radiation direction (Z-axis direction) in an X-Y plane with the center of the surface of feed element 121 as the origin.

[0028] Antenna gain A indicates the antenna gain of antenna device 100 including a patch antenna including feed element 121 and a horn antenna of peripheral electrode 150a. On the other hand, antenna gain B indicates the antenna gain of an antenna device (antenna device of the comparative example) that includes only a patch antenna including a feed element. While the antenna device of the comparative example has no gain in the range of -90° to 90°, including -180°, antenna device 100 also has gain in the range of -90° to 90°, including -180°. In other words, it can be seen that the horn antenna of peripheral electrode 150a radiates radio waves in the range of -90° to 90°, including -180°.

[0029] [Embodiment 2] In the antenna device 100 of embodiment 1, only the peripheral electrode 150a of the four peripheral electrodes 150a to 150d is configured as a horn antenna. However, in the antenna device according to the present disclosure, it is sufficient that at least one of the four peripheral electrodes 150a to 150d is configured as a horn antenna. In embodiment 2, an antenna device in which all four peripheral electrodes are configured as horn antennas will be described as an example. FIG. 5 is a perspective view of the antenna device 100A according to embodiment 2. FIG. 6 is a side perspective view of the antenna device 100A of FIG. 5. Note that in the antenna device 100A shown in FIGS. 5 and 6, the same components as those in the antenna device 100 shown in FIGS. 1 to 3 are designated by the same reference numerals, and detailed description thereof will be omitted.

[0030] The antenna device 100A can be provided in the communication device 300 shown in FIG. 2 in place of the antenna device 100. The antenna device 100A includes a feed element 121, a dielectric substrate 130, a feed line 140, peripheral electrodes 150a to 150d, and a ground electrode GND. A high-frequency signal is supplied to a feed point (not shown) of the feed element 121 from the RFIC 110 via two feed lines 140a and 140b. The feed lines 140a and 140b rise from directly below the feed element 121, penetrate the ground electrode GND, and are connected to the feed point of the feed element 121. The feed line 140a is a feed line for vertically polarized waves, and the feed line 140b is a feed line for horizontally polarized waves.

[0031] Peripheral electrodes 150a to 150d are formed on multiple dielectric layers between feed element 121 and ground electrode GND at the end of dielectric substrate 130. In antenna device 100A, peripheral electrodes 150a to 150d are arranged at positions corresponding to each side of rectangular feed element 121 when viewed in a plan view from the normal direction of dielectric substrate 130 (positive direction of the Z axis). Peripheral electrodes 150a to 150d arranged at positions corresponding to each side are arranged symmetrically with respect to the polarization direction of feed element 121 and the direction orthogonal to the polarization direction.

[0032] Each of the peripheral electrodes 150a to 150d constitutes a horn antenna. Each of the peripheral electrodes 150a to 150d includes a waveguide 151a to 151d formed in a cylindrical shape by electrodes formed in multiple layers, and a horn portion 152a to 152d connected to each of the waveguides 151a to 151d and formed in a conical shape by electrodes formed in multiple layers.

[0033] The horn antenna of peripheral electrode 150a radiates radio waves from the opening of horn portion 152a. The opening of horn portion 152a is provided on the X-axis-Z plane of dielectric substrate 130 and faces the positive direction of the Y-axis. The horn antenna of peripheral electrode 150b radiates radio waves from the opening of horn portion 152b. The opening of horn portion 152b is provided on the X-axis-Z plane of dielectric substrate 130 at a position different from the opening of horn portion 152a and faces the positive direction of the Y-axis. Therefore, the horn antennas of each of peripheral electrodes 150a-150b have a primary radiation direction in the positive direction of the Y-axis, which is different from the primary radiation direction of the patch antenna including feed element 121, which has a primary radiation direction in the positive direction of the Z-axis.

[0034] The horn antenna of peripheral electrode 150c radiates radio waves from the opening of horn portion 152c. The opening of horn portion 152c is provided on the X-axis-Z plane of dielectric substrate 130 and faces the negative direction of the Y-axis. The horn antenna of peripheral electrode 150d radiates radio waves from the opening of horn portion 152d. The opening of horn portion 152d is provided on the X-axis-Z plane of dielectric substrate 130 at a position different from the opening of horn portion 152c and faces the negative direction of the Y-axis. Therefore, the horn antennas of peripheral electrodes 150c-150d have a primary radiation direction in the negative direction of the Y-axis, which differs from the primary radiation direction of the patch antenna including feed element 121, which has a primary radiation direction in the positive direction of the Z-axis, and the horn antennas of peripheral electrodes 150a-150b, which have a primary radiation direction in the positive direction of the Y-axis.

[0035] 5, waveguide 151a and waveguide 151d are connected, and waveguide 151b and waveguide 151c are connected. A wall separating waveguide 151a and waveguide 151d may or may not be provided at the portion where waveguide 151a and waveguide 151d are connected. Also, a wall separating waveguide 151b and waveguide 151c may or may not be provided at the portion where waveguide 151b and waveguide 151c are connected.

[0036] Furthermore, as shown in FIG. 6 , peripheral electrodes 150a and 150b are further formed on multiple dielectric layers on the side opposite the side where power supply element 121 and ground electrode GND face each other. Therefore, portions of the horn antennas of peripheral electrodes 150a and 150b are formed on multiple dielectric layers on the side opposite the side where power supply element 121 and ground electrode GND face each other. That is, portions of the horn antennas of peripheral electrodes 150a and 150b are embedded in the negative direction of the Z axis relative to ground electrode GND, as shown in FIG. 6 . Similarly, although not shown, portions of the horn antennas of peripheral electrodes 150c and 150d are embedded in the negative direction of the Z axis relative to ground electrode GND. Since portions of the horn antennas of peripheral electrodes 150c to 150d are embedded in the negative direction of the Z axis relative to ground electrode GND, the radiation gain of each horn antenna of peripheral electrodes 150c to 150d is increased.

[0037] 6 is provided in a waveguide 151a constituting the horn antenna of the peripheral electrode 150a. Although not shown, the via conductor 145a is electrically connected to the power supply wiring 141 (second power supply wiring), and is fed with power from the RFIC 110 via the power supply wiring 141. When power is fed from the RFIC 110 to the via conductor 145a, the horn antenna of the peripheral electrode 150a is supplied with a high-frequency signal in this order from the waveguide 151a to the horn portion 152a, and radio waves are emitted from the opening of the horn portion 152a.

[0038] The horn antenna of peripheral electrode 150b has via conductor 145b (shown in FIG. 6 ) provided in waveguide 151b. Although not shown, via conductor 145b is electrically connected to feeder wiring 141 (second feeder wiring) and receives power from RFIC 110 via feeder wiring 141. When power is supplied from RFIC 110 to via conductor 145b, a high-frequency signal is supplied to waveguide 151b and then horn portion 152b of horn antenna of peripheral electrode 150b, and radio waves are emitted from the opening of horn portion 152b. Similarly, although not shown, via conductors are provided in each of the horn antennas of peripheral electrode 150c and peripheral electrode 150d. When power is supplied to the via conductor from RFIC 110 via feeder wiring 141, radio waves are emitted from the opening of horn portion 152c and horn portion 152d.

[0039] Here, the shape of the openings of the horn portions 152a to 152d will be described. In the antenna device 100A shown in FIG. 5, the shape of the openings of the horn portions 152a to 152d is longer than the length of the waveguide 151a in the horizontal direction of the dielectric substrate 130. However, the shape of the openings of the horn portions 152a to 152d is not limited to this. FIG. 7 is a diagram illustrating an example of the shape of the horn antenna. Note that while FIG. 7 describes the shape of the horn antenna of the peripheral electrode 150a, similar shapes can also be applied to the shapes of the horn antennas of the other peripheral electrodes 150b to 150d.

[0040] First, in the shape of the horn antenna of peripheral electrode 150a shown in Figure 7(a), the length (height H2) of the opening of horn portion 152a in the Z-axis direction (vertical direction of dielectric substrate 130) is longer than the length of waveguide 151a in the Z-axis direction (height H1 < H2). The length (width L2) of the opening of horn portion 152a in the X-axis direction (horizontal direction of dielectric substrate 130) is approximately the same as the length of waveguide 151a in the X-axis direction (width L1 = L2). Furthermore, in the shape of the horn antenna of peripheral electrode 150a shown in Figure 7(a), width L2 is shorter than height H2 (> L2).

[0041] First, regarding the shape of the horn antenna of the peripheral electrode 150a shown in FIG. 7(b), the length in the Z-axis direction (height H2) of the opening of the horn portion 152a is longer than the length in the Z-axis direction (height H1 < H2) of the waveguide 151a, and the length in the X-axis direction (width L2) of the opening of the horn portion 152a is longer than the length in the X-axis direction (width L1 < L2) of the waveguide 151a. Also, regarding the shape of the horn antenna of the peripheral electrode 150a shown in FIG. 7(b), the width L2 is longer than the height H2 (< L2). By changing the shape of the horn antenna of the peripheral electrode 150a as shown in FIGS. 7(a) and 7(b), the radiation gain of the horn antenna can be increased.

[0042] The shape of the horn antennas of the peripheral electrodes 150a to 150d is not limited to being all the same shape. The shape of each horn antenna of the peripheral electrodes 150a to 150d may be different. Note that the shape of the horn antennas of the peripheral electrodes 150a to 150d described in this embodiment can be similarly applied to the antenna device according to other embodiments.

[0043] Next, the configuration of the wall portion of the side surface (X-axis - Z-axis plane, Y-axis - Z-axis plane) of the horn antenna of the peripheral electrode 150a will be described. The wall portion of the side surface of the horn antenna of the peripheral electrode 150a shown in FIG. 5 is formed of a metal plate. However, it is not limited to this, and the wall portion of the side surface of the horn antenna of the peripheral electrode 150a may be composed of a plurality of via conductors. FIG. 8 is a diagram for explaining an example of the wall portion of the horn antenna. Note that in FIG. 8, the wall portion of the horn antenna of the peripheral electrode 150a is described, but the same configuration can be applied to the wall portions of the horn antennas of the other peripheral electrodes 150b to 150d.

[0044] The wall of the horn antenna of the peripheral electrode 150a is composed of multiple via conductors 157a-157d connecting electrode 155 and electrode 156, which are part of the peripheral electrode 150a. The diameter of each of the via conductors 157a-157d and the pitch of the via conductors 157a-157d may be any value as long as they function as the wall of the horn antenna. By configuring the wall of the horn antenna of the peripheral electrode 150a with multiple via conductors 157a-157d, the structure is similar to that of a dielectric substrate integrated waveguide (SIW), making it easy to manufacture. Note that the wall configuration of the peripheral electrodes 150a-150d described in FIG. 8 can also be applied to antenna devices according to other embodiments.

[0045] [Embodiment 3] In antenna device 100A according to embodiment 2, all four peripheral electrodes 150a to 150d are configured as horn antennas, with waveguide 151a connected to waveguide 151d and waveguide 151b connected to waveguide 151c. However, the configuration of the horn antennas of peripheral electrodes 150a to 150d in the antenna device according to the present disclosure is not limited to this configuration. Figure 9 is a perspective view of antenna device 100B according to embodiment 2. Note that in antenna device 100B shown in Figure 9, the same components as those in antenna device 100 shown in Figures 1 to 3 and antenna device 100A shown in Figure 5 are designated by the same reference numerals, and detailed description thereof will be omitted.

[0046] The antenna device 100B can be provided in the communication device 300 shown in Fig. 2 in place of the antenna device 100. The antenna device 100B includes a feed element 121, a dielectric substrate 130, a feed wiring 140, peripheral electrodes 150a to 150d, and a ground electrode GND.

[0047] Peripheral electrodes 150a to 150d are formed on multiple dielectric layers between feed element 121 and ground electrode GND at the end of dielectric substrate 130. In antenna device 100B, peripheral electrodes 150a to 150d are arranged at positions corresponding to each side of rectangular feed element 121 when viewed in a plan view from the normal direction of dielectric substrate 130 (positive direction of the Z axis). Peripheral electrodes 150a to 150d arranged at positions corresponding to each side are arranged symmetrically with respect to the polarization direction of feed element 121 and the direction orthogonal to the polarization direction.

[0048] Each of the peripheral electrodes 150a to 150d constitutes a horn antenna. Each of the peripheral electrodes 150a to 150d includes a waveguide 151a to 151d formed in a cylindrical shape by electrodes formed in multiple layers, and a horn portion 152a to 152d connected to each of the waveguides 151a to 151d and formed in a conical shape by electrodes formed in multiple layers.

[0049] 9, waveguide 151a and waveguide 151d are arranged at a distance L3 apart, and waveguide 151b and waveguide 151c are arranged at a similar distance. In other words, the horn antennas of peripheral electrodes 150a to 150d are each arranged independently in the horizontal direction of dielectric substrate 130. Therefore, antenna device 100B allows each of the horn antennas of peripheral electrodes 150a to 150d to be freely arranged in the horizontal direction of dielectric substrate 130, increasing the degree of freedom in the structure.

[0050] Furthermore, in the antenna device 100B, the height H3 from the ground electrode GND to the feed element 121 is longer than the height H1 of the waveguide 151a. Therefore, the antenna device 100B can reduce the size of the patch antenna including the feed element 121 and increase the radiation gain. Furthermore, in the antenna device 100B, it is preferable that the length L4 of one side of the feed element 121 is approximately the same as the width L1 of the waveguide 151a. Note that the length L4 of one side of the feed element 121 is considered to be approximately the same if it is within the range of 70% to 130% of the width L1 of the waveguide 151a. By making the length L4 of one side of the feed element 121 approximately the same as the width L1 of the waveguide 151a, the operating frequency band of the patch antenna including the feed element 121 and the operating frequency band of the horn antenna with the peripheral electrode 150a are approximately the same.

[0051] In the antenna device 100B shown in FIG. 9, the shape of the horn antenna of the peripheral electrode 150a is such that the height H1 of the waveguide 151a is shorter than the width L1 of the waveguide 151a. The shapes of the horn antennas of the other peripheral electrodes 150b to 150d are similar. However, the shape of the horn antenna of the peripheral electrode 150a is not limited to this shape, and the height H1 of the waveguide 151a may be longer than the width L1 of the waveguide 151a. FIG. 10 is a perspective view of an antenna device 100C according to a modification of the third embodiment. In the antenna device 100C shown in FIG. 10, the same components as those in the antenna device 100 shown in FIGS. 1 to 3 are designated by the same reference numerals, and detailed description thereof will be omitted.

[0052] The antenna device 100C can be provided in the communication device 300 shown in FIG. 2 in place of the antenna device 100. The antenna device 100C includes a feed element 121, a dielectric substrate 130, a feed wiring 140, peripheral electrodes 150a to 150d, and a ground electrode GND. In the antenna device 100C, the horn antenna of the peripheral electrode 150a is shaped such that the height H1 of the waveguide is longer than the width L1 of the waveguide. By shaping the horn antenna of the peripheral electrode 150a such that the height H1 of the waveguide is longer than the width L1 of the waveguide, the polarization direction of the horn antenna of the peripheral electrode 150a can be rotated by approximately 90° with respect to the horn antenna of the peripheral electrode 150a shown in FIG.

[0053] [Fourth Embodiment] In the antenna device 100A of the second embodiment and the antenna devices 100B and 100C of the second embodiment, a configuration in which a modification is made to the peripheral electrode horn antenna has been described. In the fourth embodiment, a configuration in which a modification is made to the patch antenna including a feed element will be described. Fig. 11 is a perspective view of an antenna device 100D according to the fourth embodiment. Note that in the antenna device 100D shown in Fig. 11, the same components as those in the antenna device 100 shown in Figs. 1 to 3 are designated by the same reference numerals, and detailed description thereof will be omitted.

[0054] The antenna device 100D can be provided in the communication device 300 shown in Fig. 2 in place of the antenna device 100. The antenna device 100D includes a feed element 121, a dielectric substrate 130, a feed wiring 140, peripheral electrodes 150a to 150d, and a ground electrode GND. The antenna device 100D further includes parasitic elements 122 and 123 disposed around the feed element 121. By disposing the parasitic elements 122 and 123 around the feed element 121, which is a patch antenna, the frequency range supported by the patch antenna can be broadened.

[0055] The parasitic elements arranged around the feed element 121 are not limited to the two parasitic elements 122 and 123, but one or three or more parasitic elements may be arranged around the feed element 121. Furthermore, the shape of the parasitic elements arranged around the feed element 121 is not limited to the shape of the parasitic elements 122 and 123 shown in Fig. 11. The configuration of the parasitic elements 122 and 123 described in Fig. 11 can be similarly applied to antenna apparatuses according to other embodiments.

[0056] Next, Fig. 12 is a perspective view of an antenna device 100E according to a first modification of the fourth embodiment. In the antenna device 100E shown in Fig. 12, the same components as those in the antenna device 100 shown in Figs. 1 to 3 are denoted by the same reference numerals, and detailed description thereof will be omitted.

[0057] The antenna device 100E can be provided in the communication device 300 shown in Fig. 2 in place of the antenna device 100. The antenna device 100E is an array antenna in which a plurality of feed elements 121a to 121d are arranged in an array as shown in Fig. 12. In particular, the antenna device 100E is a one-dimensional array antenna in which a plurality of feed elements 121a to 121d are arranged in a line.

[0058] In the antenna device 100E, peripheral electrodes 150a-150d constituting the horn antenna are arranged at positions symmetrical with respect to the polarization direction of radio waves of the feed element 121a and / or a direction perpendicular to the polarization direction. A high-frequency signal is supplied to a feed point (not shown) of the feed element 121a from the RFIC 110 via two feed lines 140a and 140b. The feed line 140a is a feed line for vertically polarized waves of the feed element 121a, and the feed line 140b is a feed line for horizontally polarized waves of the feed element 121a. Furthermore, peripheral electrodes 150b, 150c, 150e, and 150j constituting the horn antenna are arranged at positions symmetrical with respect to the polarization direction of radio waves of the feed element 121b and / or a direction perpendicular to the polarization direction. A high-frequency signal is supplied to a feed point (not shown) of the feed element 121b via two feed lines 140c and 140d from the RFIC 110. The feed line 140c is a feed line for vertically polarized waves of the feed element 121b, and the feed line 140d is a feed line for horizontally polarized waves of the feed element 121b.

[0059] Peripheral electrodes 150e, 150f, 150i, and 150j constituting the horn antenna are arranged at positions symmetrical to the polarization direction of radio waves of feed element 121c and / or a direction perpendicular to the polarization direction. A high-frequency signal is supplied to a feed point (not shown) of feed element 121c from RFIC 110 via two feed lines 140e and 140f. Feed line 140e is a feed line for vertically polarized waves of feed element 121c, and feed line 140f is a feed line for horizontally polarized waves of feed element 121c. Furthermore, peripheral electrodes 150f, 150g, 150h, and 150i constituting the horn antenna are arranged at positions symmetrical to the polarization direction of radio waves of feed element 121d and / or a direction perpendicular to the polarization direction. A high-frequency signal is supplied to a feed point (not shown) of the feed element 121d via two feed lines 140g and 140h from the RFIC 110. The feed line 140g is a feed line for vertically polarized waves of the feed element 121d, and the feed line 140h is a feed line for horizontally polarized waves of the feed element 121d.

[0060] In the antenna device 100E, a plurality of feed elements 121a to 121d are arranged in a line to form a one-dimensional array antenna, which increases the radiation gain of the antenna and enables beamforming that improves the directivity of radio waves in a predetermined direction. Note that the configuration of the parasitic elements 122 and 123 described in Fig. 12 can also be applied to the antenna devices according to the other embodiments.

[0061] Next, Fig. 13 is a perspective view of an antenna device 100F according to a second modification of the fourth embodiment. In the antenna device 100F shown in Fig. 13, the same components as those in the antenna device 100 shown in Figs. 1 to 3 are denoted by the same reference numerals, and detailed description thereof will be omitted.

[0062] The antenna device 100F can be provided in the communication device 300 shown in FIG. 2 in place of the antenna device 100. The antenna device 100F is a stacked patch antenna in which a feed element 124 is further provided on the upper surface 131 side of the feed element 121, as shown in FIG. 13 . A high-frequency signal is supplied to a feed point (not shown) of the feed element 121 from the RFIC 110 via two feed lines 140a and 140b. Furthermore, a high-frequency signal is supplied to a feed point (not shown) of the feed element 124 from the RFIC 110 via two feed lines 140c and 140d. The feed line 140a is a feed line for vertically polarized waves of the feed element 121, and the feed line 140b is a feed line for horizontally polarized waves of the feed element 121. The feed line 140c is a feed line for vertically polarized waves of the feed element 124, and the feed line 140d is a feed line for horizontally polarized waves of the feed element 124.

[0063] The antenna device 100F can accommodate more frequency bands by further providing a feed element 124. It is preferable that the length L5 of one side of the feed element 124 is approximately the same as the width L1 of the waveguide 151a. The length L5 of one side of the feed element 124 is considered to be approximately the same as long as it is within a range of 70% to 130% of the width L1 of the waveguide 151a. By making the length L5 of one side of the feed element 124 approximately the same as the width L1 of the waveguide 151a, the operating frequency band of the patch antenna including the feed element 124 and the operating frequency band of the horn antenna of the peripheral electrode 150a become approximately the same.

[0064] In the antenna device 100F, the length L5 of one side of the feed element 124 and the width L1 of the waveguide 151a may be made substantially the same, but the length L4 of one side of the feed element 121 and the width L1 of the waveguide 151a may be made substantially the same. The configuration of the feed element 124 described in Fig. 13 can also be similarly applied to antenna devices according to other embodiments.

[0065] <Aspects> (1) An antenna device according to the present disclosure comprises a dielectric substrate on which a plurality of dielectric layers are stacked; a radiating element formed on the dielectric substrate and radiating radio waves in a first polarization direction; a ground electrode arranged opposite the radiating element; and a peripheral electrode formed on a plurality of layers between the radiating element and the ground electrode and electrically connected to the ground electrode, wherein the peripheral electrode is arranged in a position symmetrical with respect to at least one of a first direction parallel to the first polarization direction and a second direction orthogonal to the first polarization direction, and at least one of the arranged peripheral electrodes forms a horn antenna.

[0066] (2) In the antenna device described in (1), the main radiation direction of the horn antenna is different from the main radiation direction of the radiating element.

[0067] (3) In the antenna device described in (1) or (2), the peripheral electrode is further formed on a plurality of dielectric layers on the side opposite to the side where the radiating element and the ground electrode face each other, and a part of the horn antenna is composed of the peripheral electrode formed on a plurality of dielectric layers on the side opposite to the side where the radiating element and the ground electrode face each other.

[0068] (4) In the antenna device described in any one of (1) to (3), the horn antenna is formed in multiple layers and the peripheral electrodes are connected by multiple via conductors, thereby forming a wall portion perpendicular to the dielectric substrate.

[0069] (5) In the antenna device described in any one of (1) to (4), the horn antenna includes a waveguide formed in a plurality of layers and configured in a cylindrical shape by the peripheral electrode, and a horn portion connected to the waveguide, formed in a plurality of layers, and configured in a conical shape by the peripheral electrode.

[0070] (6) In the antenna device described in (5), the inside of the waveguide and the horn portion includes a plurality of dielectric layers of the dielectric substrate.

[0071] (7) In the antenna device described in (5), the inside of the waveguide and the horn portion is an air gap formed by removing a plurality of dielectric layers of the dielectric substrate.

[0072] (8) The antenna device described in any one of (5) to (7) further includes a power supply circuit configured to supply a high-frequency signal, wherein the radiating element is electrically connected to a first power supply wiring and is supplied with power from the power supply circuit via the first power supply wiring, and the horn antenna is supplied with power from the power supply circuit into the waveguide via a second power supply wiring, and power is supplied to the waveguide and then the horn portion in that order.

[0073] (9) In the antenna device described in any one of (5) to (8), the opening of the horn portion is longer than the length of the waveguide in the horizontal direction of the dielectric substrate.

[0074] (10) In the antenna device described in any one of (5) to (9), the opening of the horn portion is longer than the length of the waveguide in the direction perpendicular to the dielectric substrate.

[0075] (11) In the antenna device described in any one of (5) to (10), the opening of the horn portion has a width greater than a height, where the width is the length in the horizontal direction of the dielectric substrate and the height is the length in the vertical direction of the dielectric substrate.

[0076] (12) In the antenna device described in any one of (5) to (10), the opening of the horn portion has a width that is shorter than the height, where the width is the length in the horizontal direction of the dielectric substrate and the height is the length in the vertical direction of the dielectric substrate.

[0077] (13) The antenna device according to any one of (1) to (12), further comprising a parasitic element on the layer on which the radiating element is formed, the parasitic element being disposed around the radiating element.

[0078] (14) In the antenna device according to any one of (1) to (13), the radiating elements are arranged in an array.

[0079] (15) A communication device equipped with the antenna device according to any one of (1) to (14).

[0080] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present disclosure is defined by the claims, not by the description of the above embodiments, and is intended to include all modifications within the meaning and scope of the claims.

[0081] 100, 100A to 100F Antenna device, 121, 121a to 121d, 124 Feed element, 122, 123 Parasitic element, 130 Dielectric substrate, 140, 141 Feed wiring, 145a, 145b, 157a to 157d Via conductor, 150a to 150j Peripheral electrode, 151a to 151d Waveguide, 152a to 152d Horn portion, 300 Communication device.

Claims

1. An antenna device comprising: a dielectric substrate on which a plurality of dielectric layers are laminated; a radiating element formed on the dielectric substrate and radiating radio waves in a first polarization direction; a ground electrode arranged opposite the radiating element; and a peripheral electrode formed on a plurality of layers between the radiating element and the ground electrode and electrically connected to the ground electrode, wherein the peripheral electrode is arranged in a position symmetrical with respect to at least one of a first direction parallel to the first polarization direction and a second direction orthogonal to the first polarization direction, and at least one of the arranged peripheral electrodes forms a horn antenna.

2. The antenna device according to claim 1, wherein the main radiation direction of said horn antenna is different from the main radiation direction of said radiating element.

3. An antenna device as described in claim 1 or claim 2, wherein the peripheral electrode is further formed on a plurality of dielectric layers on the side opposite to the side where the radiating element and the ground electrode face each other, and a portion of the horn antenna is composed of the peripheral electrode formed on a plurality of dielectric layers on the side opposite to the side where the radiating element and the ground electrode face each other.

4. An antenna device according to any one of claims 1 to 3, wherein the horn antenna is formed on multiple layers and the peripheral electrodes are connected by multiple via conductors, thereby forming a wall portion perpendicular to the dielectric substrate.

5. An antenna device according to any one of claims 1 to 4, wherein the horn antenna includes a waveguide formed in multiple layers and configured in a cylindrical shape by the peripheral electrodes, and a horn portion connected to the waveguide, formed in multiple layers and configured in a conical shape by the peripheral electrodes.

6. The antenna device according to claim 5, wherein the inside of said waveguide and said horn portion includes a plurality of dielectric layers of said dielectric substrate.

7. The antenna device according to claim 5, wherein the inside of said waveguide and said horn portion is an air gap formed by removing a plurality of dielectric layers of said dielectric substrate.

8. An antenna device according to any one of claims 5 to 7, further comprising a power supply circuit configured to supply a high frequency signal, wherein the radiating element is electrically connected to a first power supply wiring and is supplied with power from the power supply circuit via the first power supply wiring, and the horn antenna is supplied with power from the power supply circuit via a second power supply wiring into the waveguide, so that power is supplied to the waveguide and then to the horn portion.

9. The antenna device according to any one of claims 5 to 8, wherein the opening of the horn portion is longer than the length of the waveguide in the horizontal direction of the dielectric substrate.

10. An antenna device according to any one of claims 5 to 9, wherein the opening of the horn portion is longer than the length of the waveguide in the direction perpendicular to the dielectric substrate.

11. An antenna device according to any one of claims 5 to 10, wherein the opening of the horn portion has a width greater than a height, where the width is the length in the horizontal direction of the dielectric substrate and the height is the length in the vertical direction of the dielectric substrate.

12. An antenna device as claimed in any one of claims 5 to 10, wherein the opening of the horn portion has a width that is shorter than its height, where the width is the length in the horizontal direction of the dielectric substrate and the height is the length in the vertical direction of the dielectric substrate.

13. The antenna device according to any one of claims 1 to 12, further comprising a parasitic element around the radiating element on the layer on which the radiating element is formed.

14. The antenna device according to any one of claims 1 to 13, wherein the radiating elements are arranged in an array.

15. A communication device equipped with the antenna device according to any one of claims 1 to 14.

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