Antenna device, antenna module, and communication device

Abstract

The utility model provides an antenna device, an antenna module and a communication device. An antenna device (120) is provided with a base plate (10) on which a ground electrode (GND) is formed, and a plurality of split substrates (20) attached to the base plate (10). Each of the plurality of split substrates (20) has a dielectric substrate (23) and a plurality of antenna elements (21), and each of the plurality of antenna elements (21) radiates a radio wave having an X-axis direction as a polarization direction and a radio wave having a Y-axis direction as a polarization direction. In each of the plurality of split substrates (20), the plurality of antenna elements (21) are arranged on the dielectric substrate (23) so as to be arranged in the X-axis direction and in the Y-axis direction.

Description

Technical Field

[0001] The present disclosure relates to an antenna device including a first substrate having a ground formed thereon and a plurality of second substrates each having a plurality of antenna elements mounted thereon, an antenna module including the antenna device, and a communication device. Background Art

[0002] In the specification of U.S. Patent Application Publication No. 2021 / 0091017 (Patent Document 1), an array antenna composed of a plurality of antenna elements is disclosed. In the array antenna, a plurality of split substrates (second substrate) composed of dielectrics are mounted on a substrate (first substrate). One antenna element is arranged on each of the plurality of split substrates.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: U.S. Patent Application Publication No. 2021 / 0091017 Utility Model Content

[0006] Problems to be solved by utility models

[0007] In an array antenna, it is generally desirable to set the distance between adjacent antenna elements to be less than a specified value (a value smaller than the wavelength of the radiated radio wave). Therefore, when one antenna element is arranged on each of a plurality of split substrates as in Patent Document 1, the size of each split substrate is considerably limited in order to avoid interference between adjacent split substrates. As a result, it is not possible to fully secure the area of ​​the split substrate (dielectric substrate) for each antenna element, and there is a concern that the frequency bandwidth with good reflection loss may be narrowed due to this influence.

[0008] The present disclosure has been made to solve such a problem, and an object of the present disclosure is to expand a frequency bandwidth with good reflection loss in an antenna device including a plurality of second substrates each having an antenna element mounted on a first substrate having a ground.

[0009] Solutions for solving problems

[0010] An antenna device according to a first aspect of the present disclosure comprises: a first substrate having a ground formed thereon; and a plurality of second substrates mounted on the first substrate, wherein each of the plurality of second substrates comprises: a dielectric substrate; and a plurality of antenna elements, each of the plurality of antenna elements radiating radio waves polarized in a first direction, wherein in each of the plurality of second substrates, the plurality of antenna elements are arranged on the dielectric substrate in an array in the first direction.

[0011] Preferably, when the wavelength of the radio waves radiated by each of the multiple antenna elements in free space is set to λ, in each of the multiple second substrates, the shortest distance between each of the multiple antenna elements and the end face of the dielectric substrate in the first direction is greater than λ / 8.

[0012] Preferably, in each of the plurality of second substrates, the shortest distance between each of the plurality of antenna elements and an end surface of the dielectric substrate in the first direction is equal to or less than λ / 4.

[0013] Preferably, each of the multiple antenna elements, in addition to radiating radio waves with the first direction as polarization direction, also radiates radio waves with a second direction different from the first direction as polarization direction, and in each of the multiple second substrates, the multiple antenna elements are configured on the dielectric substrate in a manner arranged in the first direction and in the second direction.

[0014] Preferably, in each of the plurality of second substrates, the shortest distance between each of the plurality of antenna elements and the end surface of the dielectric substrate in the first direction and the shortest distance in the second direction are both greater than λ / 8.

[0015] Preferably, in each of the plurality of second substrates, the number of antenna elements arranged so as to be aligned in the first direction is the same as the number of antenna elements arranged so as to be aligned in the second direction.

[0016] An antenna module according to a second aspect of the present disclosure includes: the antenna device described above; and a feed circuit configured to supply a high-frequency signal to the plurality of antenna elements.

[0017] A communication device according to a third aspect of the present disclosure is equipped with the above-mentioned antenna module.

[0018] The antenna device of the fourth aspect of the present disclosure comprises: a first substrate having a ground formed thereon; and a plurality of second substrates mounted on the first substrate, wherein each of the plurality of second substrates comprises: a dielectric substrate; and a plurality of antenna elements, the plurality of antenna elements respectively radiating radio waves having a polarization direction in a direction inclined relative to a first direction, and in each of the plurality of second substrates, the plurality of antenna elements are arranged on the dielectric substrate in an array in the first direction.

[0019] An antenna module according to a fifth aspect of the present disclosure includes the above-mentioned antenna device; and a feeding circuit configured to supply a high-frequency signal to the plurality of antenna elements.

[0020] A communication device according to a sixth aspect of the present disclosure is equipped with the above-mentioned antenna module.

[0021] Effect of utility model

[0022] According to the present disclosure, a plurality of antenna elements are arranged on each of a plurality of split substrates, rather than one antenna element. Moreover, a plurality of antenna elements are arranged on a dielectric substrate in a manner arranged in a first direction (polarization direction). Thus, compared with a case where one antenna element is arranged on each of a plurality of split substrates, a large area of ​​the dielectric substrate in the first direction (polarization direction) can be ensured for each of the plurality of antenna elements. As a result, in an antenna device in which a plurality of second substrates each having antenna elements are mounted on a first substrate having a ground, the bandwidth with good reflection loss can be expanded. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is an example of a block diagram of a communication device to which the antenna device is applied.

[0024] Figure 2 This is a diagram showing the frequency characteristics of the reflection loss when one antenna element is arranged on one separate substrate.

[0025] Figure 3 This is a diagram showing an example of the structure of an antenna device (part 1).

[0026] Figure 4 is a perspective view of an antenna device.

[0027] Figure 5 yes Figure 4 VV cross-sectional view of the antenna device in FIG.

[0028] Figure 6 is a diagram schematically showing electric lines of force generated between an antenna element and a ground electrode.

[0029] Figure 7 This is a diagram for explaining antenna characteristics of an antenna device (part 1).

[0030] Figure 8 This is a diagram showing an example of the structure of an antenna device (part 2).

[0031] Fig. 9 This is a diagram showing an example of arrangement of antenna elements (part 1).

[0032] Fig.10 This is a diagram showing an example of arrangement of antenna elements (part 2).

[0033] Fig.11 This is a diagram for explaining antenna characteristics of the antenna device (part 2).

[0034] Fig.12 This is a diagram showing an example of the structure of an antenna device (part 3).

[0035] Fig.13 This is a diagram (part 4) showing an example of the structure of an antenna device.

[0036] Fig.14 This is a diagram showing an example of the structure of an antenna device (part 5).

[0037] Fig.15 This is a diagram (part 6) showing an example of the structure of an antenna device. DETAILED DESCRIPTION

[0038] Hereinafter, the embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In addition, the same reference numerals are given to the same or corresponding parts in the drawings, and their description will not be repeated.

[0039] (Basic structure of communication device)

[0040] Figure 1 This is an example of a block diagram of a communication device 1 to which the antenna device 120 of the present embodiment is applied. The communication device 1 is, for example, a portable terminal such as a mobile phone, a smartphone, or a tablet, or a personal computer having a communication function.

[0041] Reference Figure 1 The communication device 1 includes an antenna module 100 and a BBIC 200 constituting a baseband signal processing circuit. The antenna module 100 includes an antenna device 120 and an RFIC 110 as an example of a feeding circuit. The communication device 1 up-converts a signal transmitted from the BBIC 200 to the antenna module 100 into a high-frequency signal and radiates the signal from the antenna device 120, and down-converts a high-frequency signal received by the antenna device 120 and processes the signal in the BBIC 200.

[0042] The antenna device 120 includes a plurality of antenna elements 121. In the present embodiment, the antenna element 121 is a patch antenna having a substantially square flat plate shape.

[0043] The RFIC 110 is connected between the antenna device 120 and the BBIC 200. Figure 1 In the figure, for ease of explanation, only the structures corresponding to the four antenna elements 121 in the structure of the RFIC 110 are shown, and the structures corresponding to the other antenna elements 121 having the same structure are omitted.

[0044] The antenna device 120 of this embodiment is a so-called dual-polarization type array antenna that can radiate two radio waves having mutually different polarization directions from each antenna element 121 as described later. Therefore, a high-frequency signal for the first polarization and a high-frequency signal for the second polarization are supplied from the RFIC 110 to each antenna element 121. Figure 1 In the figure, for ease of explanation, only the structure of the RFIC 110 corresponding to the high-frequency signal for the first polarization is shown, and the structure corresponding to the high-frequency signal for the second polarization having the same structure is omitted.

[0045] RFIC 110 includes switches 111A to 111D, 113A to 113D, and 117 , power amplifiers 112AT to 112DT, low noise amplifiers 112AR to 112DR, attenuators 114A to 114D, phase shifters 115A to 115D, a signal synthesizer / demultiplexer 116 , a mixer 118 , and an amplifier circuit 119 .

[0046] When transmitting a high-frequency signal, switches 111A to 111D and 113A to 113D are switched to the power amplifiers 112AT to 112DT, and switch 117 is connected to the transmitting-side amplifier of amplifier circuit 119. When receiving a high-frequency signal, switches 111A to 111D and 113A to 113D are switched to the low-noise amplifiers 112AR to 112DR, and switch 117 is connected to the receiving-side amplifier of amplifier circuit 119.

[0047] The signal transmitted from the BBIC 200 is amplified by the amplifier circuit 119 and up-converted by the mixer 118. The high-frequency signal obtained by the up-conversion, i.e., the transmission signal, is divided into four waves by the signal synthesizer / demultiplexer 116, and after passing through four signal paths, they are fed to different antenna elements 121. At this time, the directivity of the antenna device 120 can be adjusted by individually adjusting the phase shift degree of the phase shifters 115A to 115D arranged in each signal path.

[0048] The high frequency signals, i.e., reception signals received by the antenna elements 121 are combined by the signal combiner / demultiplexer 116 via four different signal paths. The combined reception signals are down-converted by the mixer 118 and amplified by the amplifier circuit 119 before being transmitted to the BBIC 200.

[0049] RFIC 110 is formed, for example, as a single-chip integrated circuit component including the above-mentioned circuit structure. Alternatively, the devices (switches, power amplifiers, low-noise amplifiers, attenuators, phase shifters) corresponding to each antenna element 121 in RFIC 110 can also be formed as a single-chip integrated circuit component for each corresponding antenna element 121.

[0050] (Structure of antenna device)

[0051] In the antenna device 120 of the present embodiment, a plurality of separate substrates are mounted on a base substrate having a ground, and an antenna element 121 is arranged on each separate substrate. By arranging the ground and the antenna element on different substrates, the degree of freedom in design is increased compared to the case where the ground and the antenna element are arranged on the same substrate. Therefore, for example, it is easy to take measures such as limiting the location where a relatively expensive high dielectric material is used to reduce the material cost of the substrate.

[0052] When the antenna elements are arranged on the separate substrates as described above, if one antenna element is arranged on one separate substrate, there is a concern that the frequency bandwidth in which the reflection loss is good will be narrowed.

[0053] Figure 2 FIG. 2 is a graph showing the frequency characteristics of the reflection loss when one antenna element is arranged on one separate substrate. Figure 2 In FIG. 1 , the horizontal axis shows the frequency (GHz), and the vertical axis shows the reflection loss as the attenuation amount.

[0054] Here, the reflection loss is a loss obtained by expressing the ratio of the reflected power to the power input to the antenna device in decibels (dB). In the case of total reflection (reflectivity is 100%), the reflection loss value is 0dB, and the less the reflection, the greater the reflection loss value. In other words, the greater the reflection loss value, the smaller the power loss itself caused by reflection, and the better the reflection loss.

[0055] exist Figure 2 , the reflection characteristics S1 to S5 are shown when the length of one side of the split substrate (= L1 = L2) is changed on the basis of configuring an antenna element in the center of a square-shaped split substrate. Reflection characteristic S1 is the characteristic when the length of one side of the split substrate is set to 5 mm. Reflection characteristic S2 is the characteristic when the length of one side of the split substrate is set to 6 mm. Reflection characteristic S3 is the characteristic when the length of one side of the split substrate is set to 7 mm. Reflection characteristic S4 is the characteristic when the length of one side of the split substrate is set to 8 mm. Reflection characteristic S5 is the characteristic when the length of one side of the split substrate is set to 9 mm.

[0056] In addition, Figure 2 In the example, when the length of one side of the split substrate is set to 7 mm, the shortest distance between the antenna element and the end surface of the split substrate (= D1 = D2) is approximately λ / 4. Here, "λ" is the wavelength of the radio wave radiated by the antenna element in free space.

[0057] from Figure 2It can be seen that the longer the length of one side of the split substrate is, the greater the reflection loss is. Moreover, when the reference value of the reflection loss is set to 17 dB, for example, the longer the length of one side of the split substrate is, the wider the frequency range (bandwidth with good reflection loss) where the reflection loss is above the reference value is.

[0058] However, in an array antenna, it is generally desirable to set the distance between adjacent antenna elements to be less than λ (e.g., λ / 2). Therefore, if the length of one side of the split substrate is increased, the adjacent split substrates will abut against each other, so the length of one side of the split substrate cannot be sufficiently increased. In other words, when one antenna element is configured on each of the multiple split substrates, the area of ​​the split substrate (dielectric substrate) cannot be sufficiently ensured for each antenna element, and there is a concern that the bandwidth with good reflection loss will be narrowed due to this influence.

[0059] Therefore, in the present embodiment, a plurality of antenna elements are arranged on each of the plurality of separate substrates, instead of arranging a single antenna element.

[0060] Figure 3 1 is a diagram showing an example of the structure of the antenna device 120 according to the present embodiment. Figure 3 On the left side of FIG. 1 , as a comparative example to be compared with the antenna device 120 of the present embodiment, a structure of an antenna device is shown in which 16 separate substrates are arranged in a two-dimensional form of 4×4 on a ground substrate and one antenna element is arranged on the separate substrates.

[0061] exist Figure 3 On the right side of FIG. 1 , as an example of the structure of the antenna device 120 according to the present embodiment, an example is shown in which four separate substrates 20 are arranged on the main surface of the ground substrate 10 and four antenna elements 21 are arranged on each of the four separate substrates 20 .

[0062] In addition, hereinafter, the normal direction of the main surface of the ground plate 10 is also referred to as the "Z-axis direction", and the directions perpendicular to the Z-axis direction and perpendicular to each other are also referred to as the "X-axis direction" and the "Y-axis direction", respectively. In addition, in the following, the positive direction of the Z-axis in each figure is sometimes set as the upper surface side, and the negative direction is set as the lower surface side for description.

[0063] The antenna elements 21 are dual-polarized antenna elements capable of radiating radio waves with the X-axis direction as the polarization direction and radio waves with the Y-axis direction as the polarization direction. Figure 3 The antenna element 21 shown corresponds to Figure 1 Antenna element 121 is shown.

[0064] like Figure 3As shown, in the antenna device 120 of the present embodiment, four separate substrates 20 are arranged on the main surface of the ground substrate 10, two of which are arranged in the X-axis direction and two in the Y-axis direction. In addition, four antenna elements 21 are arranged on each of the four separate substrates 20, two of which are arranged in the X-axis direction and two in the Y-axis direction.

[0065] That is, in the antenna device 120 of the present embodiment, a plurality of antenna elements 21 are arranged in a polarization direction (X-axis direction and Y-axis direction) on each of the plurality of split substrates 20. Thus, the size of each split substrate can be increased compared to a comparative example in which one antenna element is arranged on each of the plurality of split substrates. Thus, a large area of ​​the split substrate 20 (dielectric substrate) in the polarization direction can be ensured for each of the plurality of antenna elements 21. As a result, the frequency bandwidth with good reflection loss can be expanded.

[0066] Figure 4 is a perspective view of the antenna device 120 according to this embodiment. Figure 4 The structure of the antenna device 120 according to this embodiment will be described in further detail.

[0067] The antenna device 120 includes a ground substrate 10 and four separate substrates 20 . The four separate substrates 20 are arranged on the upper surface of the ground substrate 10 at predetermined intervals and two of each of the separate substrates 20 are arranged in the X-axis direction and the Y-axis direction.

[0068] Each of the separate substrates 20 includes four antenna elements 21 and a dielectric substrate 23. The dielectric substrate 23 is formed in a substantially square shape when viewed from above in the Z-axis direction. The four antenna elements 21 are arranged on the dielectric substrate 23 in such a manner that two antenna elements 21 are arranged in the X-axis direction and two antenna elements are arranged in the Y-axis direction.

[0069] Thus, the antenna device 120 of the present embodiment is an array antenna having a total of 16 antenna elements 21 arranged by mounting four separate substrates 20 each having four antenna elements 21 on the ground substrate 10. In addition, in the present embodiment, the distance between adjacent antenna elements (the distance between the center of the surface (the intersection of the diagonal lines) of adjacent antenna elements 21) is set to approximately λ / 2.

[0070] Figure 5 yes Figure 4 FIG. 1 is a cross-sectional view of the antenna device 120 in FIG. Figure 5 In the figure, part of the cross-sectional shape is omitted.

[0071] The ground substrate 10 includes a dielectric 11 and a ground electrode GND arranged in a layer inside the dielectric 11. The ground electrode GND has a flat plate shape extending in the Y-axis direction and the X-axis direction.

[0072] The dielectric substrate 23 of the separate substrate 20 has an upper surface 23a and a lower surface 23b facing the upper surface 23a. On the upper surface 23a of the dielectric substrate 23, two antenna elements 21 are arranged in the Y-axis direction at a predetermined interval.

[0073] Mounting terminal portions 24 for mounting the dielectric substrate 23 on the upper surface (main surface) 10a of the ground substrate 10 are arranged on the lower surface 23b of the dielectric substrate 23. The mounting terminal portions 24 are formed of a plurality of conductive bodies such as solder bumps.

[0074] Thus, in the antenna device 120 of the present embodiment, the number of antenna elements 21 arranged in the Y-axis direction of one separate substrate 20 is set to two (a plurality) instead of one. Thus, the size of each separate substrate 20 in the Y-axis direction can be increased compared to the case where one antenna element 21 is arranged in the Y-axis direction of one separate substrate 20. As a result, the area of ​​the dielectric substrate 23 in the Y-axis direction (polarization direction) can be sufficiently ensured for each antenna element 21.

[0075] Figure 6 Schematically shows the electric lines of force generated between the antenna element 21 and the ground electrode GND when each antenna element 21 radiates an electric wave with the Y-axis direction as the polarization direction. In this embodiment, as described above, the area of ​​the dielectric substrate 23 in the Y-axis direction can be sufficiently ensured for each antenna element 21. Therefore, the electric lines of force generated between the antenna element 21 and the ground electrode GND can be received inside the dielectric substrate 23, and an ideal electric field state can be formed. As a result, the frequency bandwidth with good reflection loss for the electric wave with the Y-axis direction as the polarization direction can be expanded.

[0076] In the antenna device 120 of the present embodiment, two (plural) antenna elements 21 are arranged on one separate substrate 20 in a manner arranged in the X-axis direction. Thus, the area of ​​the dielectric substrate 23 in the X-axis direction can be sufficiently ensured for each antenna element 21. Therefore, when each antenna element 21 radiates radio waves with the X-axis direction as the polarization direction, an ideal electric field state can be formed. As a result, the frequency bandwidth with good reflection loss of radio waves with the X-axis direction as the polarization direction can be expanded.

[0077] In the antenna device 120 of the present embodiment, the number of antenna elements 21 arranged in the X-axis direction and the number of antenna elements 21 arranged in the Y-axis direction are the same value (2) in each of the plurality of separate substrates 20. Thus, compared with the case where the number of antenna elements 21 arranged in the X-axis direction and the number of antenna elements 21 arranged in the Y-axis direction are different values, the shape of each separate substrate 20 can be made closer to a square, so the symmetry of each separate substrate 20 can be improved. Therefore, each separate substrate 20 can be easily mounted on the ground substrate 10.

[0078] Figure 7 is a diagram for explaining the antenna characteristics of the antenna device 120 according to this embodiment. Figure 7 The upper side shows Figure 3 The characteristics of the antenna device of the comparative example structure (a structure in which one antenna element is arranged on each separate substrate) are shown. Figure 7 The lower side of shows the characteristics of the antenna device 120 according to this embodiment.

[0079] In addition, Figure 7 In FIG. 1 , the structure of the antenna device and the graph of the reflection loss are shown in order from the left. The graph of the reflection loss shows the two antenna elements on the upper left of each antenna device (in Figure 7 , which is a graph of the reflection loss in the X-axis direction and a graph of the reflection loss in the Y-axis direction of the antenna (in the structure, there are two antenna elements surrounded by a frame).

[0080] In the antenna device of the comparative example, the frequency bandwidth with good reflection loss (the frequency range in which the reflection loss is 17 dB or more as a reference value) is narrowed. It is believed that the main reason for this is that since one antenna element is arranged on each separate substrate, it is not possible to ensure a sufficient area of ​​the separate substrate (dielectric substrate) in the polarization direction for each antenna element.

[0081] In contrast, in the antenna device 120 of the present embodiment, the frequency bandwidth with good reflection loss is wider than that of the comparative example. This is considered to be mainly because, since a plurality of antenna elements 21 are arranged in a polarization direction (X-axis direction and Y-axis direction) on each separate substrate 20, the area of ​​the separate substrate 20 (dielectric substrate 23) in the polarization direction can be sufficiently ensured for each antenna element.

[0082] As described above, the antenna device 120 of the present embodiment includes a ground substrate 10 having a ground electrode GND formed thereon and a plurality of split substrates 20 mounted on the ground substrate 10. Each of the plurality of split substrates 20 has a dielectric substrate 23 and a plurality of antenna elements 21, wherein the plurality of antenna elements 21 radiate radio waves with the X-axis direction as polarization direction and radio waves with the Y-axis direction as polarization direction, respectively. The plurality of antenna elements 21 are arranged on the dielectric substrate 23 in a manner arranged in the X-axis direction and in the Y-axis direction. Thus, compared with a case where one antenna element 21 is arranged on each of the plurality of split substrates 20, a large area of ​​the dielectric substrate 23 in the polarization direction (X-axis direction and Y-axis direction) can be ensured for each of the plurality of antenna elements 21. As a result, the frequency bandwidth with good reflection loss can be expanded.

[0083] Furthermore, the “ground substrate 10 ,” “separate substrate 20 ,” “dielectric substrate 23 ,” and “antenna element 21 ” of the present embodiment may correspond to the “first substrate,” “second substrate,” “dielectric substrate,” and “antenna element” of the present disclosure, respectively.

[0084] [Modification 1]

[0085] In the above embodiment, since a plurality of antenna elements 21 are arranged on one separate substrate 20 (dielectric substrate 23 ), each antenna element 21 is arranged at a position closer to the end surface than the center of the dielectric substrate 23 .

[0086] Here, the range of λ / 8 from the end face of the antenna element 21 is a region where electric lines of force are particularly concentrated, so it is desirable that the dielectric substrate 23 rather than the air layer exists in this region. Based on this, in each of the plurality of separate substrates 20, the shortest distance between each of the plurality of antenna elements 21 and the end face of the dielectric substrate 23 in the polarization direction (X-axis direction and Y-axis direction) may be set to be greater than λ / 8.

[0087] Figure 8 1 is a diagram showing an example of the structure of the antenna device 120A according to the first modification. Figure 8 As shown, in the antenna device 120A of the first modification, the shortest distance in the X-axis direction and the shortest distance in the Y-axis direction between each antenna element 21 and the end surface of the dielectric substrate 23 in each of the four separate substrates 20 are set to approximately λ / 8. As a result, the area where the electric lines of force generated between the antenna element 21 and the ground electrode GND are concentrated can be set to the dielectric substrate 23 instead of the air layer. Therefore, an ideal electric field state can be formed to appropriately expand the frequency bandwidth with good reflection loss.

[0088] In addition, the shortest distance in the polarization direction between each of the plurality of antenna elements 21 and the end surface of the dielectric substrate 23 may be set to be less than λ / 4 in each of the plurality of split substrates 20. In this way, the distance between the antenna elements 21 of two adjacent split substrates 20 in the polarization direction can be set to be less than λ / 2, thereby reducing unnecessary side lobes called gratings.

[0089] [Modification 2]

[0090] In the above embodiment, four separate substrates 20 are arranged in a 2×2 two-dimensional shape on the ground substrate 10, and four antenna elements 21 are arranged in a 2×2 two-dimensional shape on each of the four separate substrates 20, thereby forming an array antenna having a total of 16 antenna elements 21.

[0091] However, the total number of antenna elements 21 is not limited to 16. In addition, the arrangement of antenna elements 21 in each separate substrate 20 is not limited to 2×2.

[0092] Fig. 9 The diagram shows an example of arrangement of the antenna elements 21 in each of the separate substrates 20 when a total of 36 antenna elements 21 are arranged in a two-dimensional form of 6×6.

[0093] You can also Fig. 9 As shown in the lower left part of , nine separate substrates 20 are arranged on the ground substrate 10, and four antenna elements 21 are arranged in a two-dimensional form of 2×2 on each separate substrate 20.

[0094] Alternatively, you can Fig. 9 As shown in the lower center of , four separate substrates 20 are arranged on the ground substrate 10, and nine antenna elements 21 are arranged in a two-dimensional form of 3×3 on each separate substrate 20.

[0095] Alternatively, you can Fig. 9 As shown in the lower right side of , six split substrates 20 are arranged on the ground substrate 10, 16 antenna elements 21 are arranged in a 4×4 two-dimensional shape on one split substrate 20, and four antenna elements 21 are arranged in a 2×2 two-dimensional shape on each of the remaining five split substrates 20.

[0096] In either arrangement, a total of 36 antenna elements 21 can be arranged in a two-dimensional form of 6×6.

[0097] [Variation 3]

[0098] In the above-described embodiment, an example in which the antenna element 21 is a dual-polarization antenna element has been described, but the antenna element 21 may be a single-polarization antenna element.

[0099] Fig.10 1 is a diagram showing an example of arrangement of the antenna element 21 when the antenna element 21 is a single-polarization antenna element.

[0100] like Fig.10 As shown on the upper side of , when the antenna element 21 radiates radio waves with the X-axis direction as the polarization direction, it is sufficient to arrange a plurality of antenna elements 21 in the X-axis direction in one dimension on each of the separate substrates 20 .

[0101] In addition, if Fig.10 As shown in the lower side of , when the antenna element 21 radiates radio waves with the Y-axis direction as the polarization direction, it is sufficient to arrange a plurality of antenna elements 21 in the Y-axis direction in one dimension on each separate substrate 20 .

[0102] With such an arrangement, a large area of ​​the dielectric substrate 23 in the polarization direction (X-axis direction or Y-axis direction) can be ensured for each antenna element 21, so that the frequency bandwidth with good reflection loss can be expanded.

[0103] Fig.11 : is a diagram for explaining the antenna characteristics of the antenna device of this modification example 3. Fig.11 The upper side shows Figure 3 The characteristics of the antenna device of the comparative example structure (a structure in which one antenna element is arranged on each separate substrate) are shown. Fig.11 The lower side shows Fig.10 The characteristics of the structure shown on the upper side (a structure in which a plurality of antenna elements 21 that radiate radio waves with the X-axis direction as the polarization direction are arranged in the X-axis direction on each separate substrate).

[0104] from Fig.11 It can be seen that in the antenna device of this modification example 3, the frequency bandwidth with good reflection loss is wider than that of the comparative example. It is believed that the main reason for this is that since a plurality of antenna elements 21 are arranged in a polarization direction (X-axis direction) on each separate substrate 20, the area of ​​the separate substrate 20 (dielectric substrate 23) in the polarization direction can be sufficiently ensured for each antenna element 21.

[0105] As described above, when the antenna element 21 is a single-polarization antenna element, a plurality of antenna elements 21 may be arranged on each of the separate substrates 20 so as to be aligned in the polarization direction of the radiated radio waves.

[0106] [Variation 4]

[0107] In the above-described embodiment, an example is shown in which, when each antenna element 21 is viewed from above in the Z-axis direction, the four sides of each antenna element 21 are aligned with the direction in which the plurality of antenna elements 21 are arranged on the separate substrate 20 (in the Figure 3 In the example shown, the X-axis direction and the Y-axis direction (hereinafter also referred to as the "arrangement direction of the plurality of antenna elements") are parallel or orthogonal. However, when viewed from the Z-axis direction, the four sides of each antenna element may be inclined (intersecting at an acute angle or an obtuse angle) relative to the arrangement direction of the plurality of antenna elements (the X-axis direction and the Y-axis direction).

[0108] Fig.12 1 is a diagram showing an example of the configuration of an antenna device 120B according to Modification 4. In the antenna device 120B, the antenna element 21 of the antenna device 120 according to the above-described embodiment is changed to an antenna element 21B.

[0109] The antenna element 21B is arranged so that, when viewed from above in the Z-axis direction, the four sides of each antenna element 21B are inclined at approximately 45 degrees relative to the arrangement direction (X-axis direction and Y-axis direction) of the plurality of antenna elements 21B. In addition, the polarization direction of the antenna element 21B is the same as the polarization direction of the above-mentioned antenna element 21. Specifically, the antenna element 21B is configured to be able to radiate radio waves with the X-axis direction as the polarization direction and radio waves with the Y-axis direction as the polarization direction.

[0110] In this way, a plurality of antenna elements 21B, each of which has four sides inclined with respect to the X-axis direction and the Y-axis direction, can be arranged on the separate substrate 20 in a manner arranged in the X-axis direction and in the Y-axis direction. In such a structure, a large area of ​​the dielectric substrate 23 in the polarization direction (X-axis direction and Y-axis direction) of the antenna element 21B can be ensured for each of the plurality of antenna elements 21B, compared with a case where one antenna element 21B is arranged on each separate substrate 20. As a result, the frequency bandwidth with good reflection loss can be expanded.

[0111] [Variation 5]

[0112] In the above-mentioned embodiment, an example is shown in which, when each antenna element 21 is viewed from above in the Z-axis direction, the polarization direction of each antenna element 21 and the arrangement direction of the plurality of antenna elements 21 (in Figure 3 In the example shown, the X-axis direction and the Y-axis direction are parallel or orthogonal. However, when viewed from the Z-axis direction, the polarization direction of each antenna element may be inclined (intersecting at an acute angle or an obtuse angle) relative to the configuration direction of the plurality of antenna elements.

[0113] Fig.131 is a diagram showing an example of the configuration of an antenna device 120C according to Modification 5. In the antenna device 120C, the antenna element 21 of the antenna device 120 according to the above-described embodiment is replaced with an antenna element 21C.

[0114] The antenna element 21C is configured to be able to radiate radio waves with a polarization direction of a first tilted direction x1 tilted at approximately 45 degrees relative to the X-axis direction and a radio wave with a polarization direction of a second tilted direction y1 tilted at approximately 45 degrees relative to the Y-axis direction. In addition, the first tilted direction x1 and the second tilted direction y1 are substantially orthogonal to each other. In addition, similarly to the antenna device 120, the four sides of each antenna element 21C are arranged to be parallel or orthogonal to the arrangement direction (X-axis direction and Y-axis direction) of the plurality of antenna elements 21C.

[0115] In this way, when viewed from the Z-axis direction, the polarization direction (first oblique direction x1 and second oblique direction y1) of each antenna element 21C can also be inclined (intersected at an acute angle or an obtuse angle) relative to the arrangement direction (X-axis direction and Y-axis direction) of the plurality of antenna elements 21C. Compared with the case where one antenna element 21C is arranged on each separate substrate 20, in such a structure, it is possible to ensure that the area of ​​the dielectric substrate 23 in the polarization direction (first oblique direction x1 and second oblique direction y1) of the antenna element 21C is large for each of the plurality of antenna elements 21C. As a result, the frequency bandwidth with good reflection loss can be expanded.

[0116] [Variation 6]

[0117] A structure in which the structure of the above-mentioned modification example 4 and the structure of the modification example 5 are combined may be adopted.

[0118] Fig.14 1 is a diagram showing an example of the configuration of an antenna device 120D according to Modification 6. In the antenna device 120D, the antenna element 21 of the antenna device 120 according to the above-described embodiment is replaced with an antenna element 21D.

[0119] The antenna elements 21D are arranged so that, when viewed in plan from the Z-axis direction, four sides of each antenna element 21D are inclined at approximately 45 degrees with respect to the arrangement direction (X-axis direction and Y-axis direction) of the plurality of antenna elements 21D.

[0120] The antenna element 21D is configured to radiate radio waves polarized in a first tilted direction x1 tilted by approximately 45 degrees with respect to the X-axis direction and radio waves polarized in a second tilted direction y1 tilted by approximately 45 degrees with respect to the Y-axis direction.

[0121] In this way, a plurality of antenna elements 21D whose four sides and polarization directions are inclined with respect to the X-axis direction and the Y-axis direction can be arranged on the separate substrate 20 in a manner arranged in the X-axis direction and in the Y-axis direction. In such a structure, a large area of ​​the dielectric substrate 23 in the polarization direction (the first inclined direction x1 and the second inclined direction y1) of the antenna element 21D can be ensured for each of the plurality of antenna elements 21D, compared with a case where one antenna element 21D is arranged on each separate substrate 20. As a result, the frequency bandwidth with good reflection loss can be expanded.

[0122] [Variation 7]

[0123] In the above-mentioned embodiment, a so-called single-band type antenna device 120 is exemplified. However, the antenna device to which the present disclosure is applied is not limited to the single-band type, and may be a so-called dual-band type.

[0124] Fig.15 1 is a diagram showing an example of the configuration of an antenna device 120E according to Modification 7. The antenna device 120E is obtained by adding a plurality of antenna elements 21E to the antenna device 120 according to the above-described embodiment.

[0125] The plurality of antenna elements 21E are respectively arranged relative to the plurality of antenna elements 21. Each antenna element 21E is arranged at a predetermined interval in the Z-axis direction relative to the antenna element 21 corresponding to each antenna element 21E. When viewed from above in the Z-axis direction, each antenna element 21E is arranged at a position overlapping with the antenna element 21 corresponding to each antenna element 21E. In addition, when viewed from above in the Z-axis direction, the size of the antenna element 21E is smaller than the size of the antenna element 21. The antenna element 21E is configured to be able to radiate radio waves having a frequency higher than the frequency of the radio waves radiated by the antenna element 21. In addition, the polarization direction of the antenna element 21E can be either the polarization direction of the above-mentioned antenna element 21 (X-axis direction and Y-axis direction) or the polarization direction of the above-mentioned antenna element 21C (the first oblique direction x1 and the second oblique direction y1).

[0126] In this way, a so-called dual-band antenna device 120E may be adopted.

[0127] The embodiments disclosed this time should be considered as illustrative in all aspects and not restrictive. The scope of the present invention is indicated by the claims rather than the description of the embodiments described above, and is intended to include all modifications within the meaning and scope equivalent to the claims.

[0128] Description of Reference Numerals

[0129] 1: communication device; 10: ground substrate; 10a, 23a: upper surface; 11: dielectric; 20: split substrate; 21, 21B, 21C, 21D, 21E, 121: antenna element; 23: dielectric substrate; 23b: lower surface; 24: mounting terminal portion; 100: antenna module; 111A~111D, 113A~113D, 117: switch; 112AR~112DR: low noise amplifier; 112AT~112DT: power amplifier; 114A~114D: attenuator; 115A~115D: phase shifter; 116: signal synthesizer / demultiplexer; 118: mixer; 119: amplifier circuit; 120, 120A~120E: antenna device; GND: ground electrode.

Claims

1. An antenna device, characterized in that: have: A first substrate having a ground formed thereon; and a plurality of second substrates, wherein the plurality of second substrates are mounted on the first substrate, Wherein, each of the plurality of second substrates has: a dielectric substrate; and a plurality of antenna elements, each of which radiates radio waves with a first direction as a polarization direction; In each of the plurality of second substrates, the plurality of antenna elements are arranged on the dielectric substrate in a manner aligned in the first direction. When the wavelength of the radio wave radiated by each of the multiple antenna elements in free space is set to λ, in each of the multiple second substrates, the shortest distance between each of the multiple antenna elements and the end surface of the dielectric substrate in the first direction is greater than λ / 8.

2. The antenna device according to claim 1, characterized in that In each of the plurality of second substrates, the shortest distance between each of the plurality of antenna elements and an end surface of the dielectric substrate in the first direction is equal to or less than λ / 4.

3. The antenna device according to claim 2, characterized in that Each of the plurality of antenna elements radiates a radio wave polarized in a second direction different from the first direction in addition to radiating a radio wave polarized in the first direction. In each of the plurality of second substrates, the plurality of antenna elements are arranged on the dielectric substrate so as to be aligned in the first direction and aligned in the second direction.

4. The antenna device according to claim 3, characterized in that: In each of the plurality of second substrates, the shortest distance between each of the plurality of antenna elements and the end surface of the dielectric substrate in the first direction and the shortest distance in the second direction are both greater than λ / 8.

5. The antenna device according to claim 3 or 4, characterized in that: In each of the plurality of second substrates, the number of antenna elements arranged so as to be aligned in the first direction is the same as the number of antenna elements arranged so as to be aligned in the second direction.

6. An antenna module, characterized in that: have: The antenna device according to any one of claims 1 to 5; and The feeding circuit is configured to supply a high-frequency signal to the plurality of antenna elements.

7. A communication device, characterized in that: The antenna module according to claim 6 is mounted.

8. An antenna device, characterized in that: have: A first substrate having a ground formed thereon; and a plurality of second substrates, wherein the plurality of second substrates are mounted on the first substrate, Wherein, each of the plurality of second substrates has: a dielectric substrate; and a plurality of antenna elements, each of which radiates a radio wave having a polarization direction inclined relative to the first direction, In each of the plurality of second substrates, the plurality of antenna elements are arranged on the dielectric substrate so as to be aligned in the first direction.

9. An antenna module, characterized in that: have: The antenna device according to claim 8; and The feeding circuit is configured to supply a high-frequency signal to the plurality of antenna elements.

10. A communication device, characterized in that: The antenna module according to claim 9 is mounted.

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