Antenna module and communication device equipped with same

Abstract

The antenna module includes a dielectric substrate, a first ground electrode and a second ground electrode disposed on the dielectric substrate, a plurality of first antenna elements disposed along a first direction, the plurality of first antenna elements facing the first ground electrode in a second direction different from the first direction, and a second antenna element disposed along the second direction. The second antenna element faces the second ground electrode in the second direction, and is disposed between adjacent first antenna elements when viewed from a third direction orthogonal to the first direction and the second direction. Each of the adjacent first antenna elements includes a first radiating element and a second radiating element disposed between the first radiating element and the first ground electrode, the second antenna element includes a third radiating element, the first radiating element, the second radiating element, and the third radiating element have a flat plate shape, and in a third direction, the first radiating element is disposed between the first ground electrode and the second ground electrode. The size of the second radiating element is larger than the size of the first radiating element, and the facing distance between the third radiating element and the second ground electrode is shorter than the facing distance between the first radiating element and the first ground electrode.

Description

Technical Field

[0001] The present disclosure relates to an antenna module and a communication device equipped with the antenna module, and more particularly, to a technology for preventing antenna gain from decreasing. Background Art

[0002] Generally speaking, when multiple patch antennas are arranged in a row, the relationship between the wavelength of the patch antennas and the spacing (center-to-center distance) between adjacent patch antennas affects the antenna gain. Therefore, when multiple patch antennas are arranged in a row, it is desirable to achieve an optimal spacing that takes into account the wavelength of the patch antennas.

[0003] This also applies to the case where a plurality of stacked patch antennas are arranged in a row. However, stacked patch antennas are formed by stacking a plurality of patches of different wavelengths in order to support a plurality of frequency bands, and therefore it is difficult to optimize the spacing between adjacent stacked patch antennas.

[0004] The following antenna device is disclosed in the specification of U.S. Patent Application Publication No. 2021 / 0044028 (Patent Document 1): a plurality of stacked patch antennas formed by stacking a first patch supporting a first frequency and a second patch supporting a second frequency higher than the first frequency, and a second patch is added between adjacent stacked patch antennas. In the antenna device described in Patent Document 1, the second patch in the stacked patch antenna and the second patch added between adjacent stacked patch antennas are adjusted to be at the same height from the ground layer.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: U.S. Patent Application Publication No. 2021 / 0044028 Summary of the invention

[0008] Problem that the invention aims to solve

[0009] According to the antenna device described in Patent Document 1, by adjusting the spacing between the stacked patch antennas and the second patch added between the stacked patch antennas, it is possible to achieve an optimal spacing that takes into account the wavelengths of both the first patch and the second patch. However, in the antenna device described in Patent Document 1, since the facing distance between the second patch added between adjacent stacked patch antennas and the ground layer becomes longer, a high-order mode surface acoustic wave is generated at the added second patch. As a result, a problem occurs in which the antenna gain in the front of the radiation direction at the added second patch unit is reduced.

[0010] The present disclosure is completed to solve the problem as mentioned above, and its purpose is to prevent the antenna gain from being reduced in an antenna module, in which a second antenna element including a third radiating element is configured between adjacent first antenna elements among a plurality of first antenna elements formed by stacking first radiating elements and second radiating elements of different sizes.

[0011] Solutions for solving problems

[0012] An antenna module according to a first aspect of the present disclosure includes: a dielectric substrate; a first ground electrode and a second ground electrode arranged on the dielectric substrate; a plurality of first antenna elements arranged along a first direction on the dielectric substrate; and a second antenna element arranged on the dielectric substrate, wherein the plurality of first antenna elements face the first ground electrode in a second direction different from the first direction, the second antenna element faces the second ground electrode in the second direction, the second antenna element is arranged between adjacent first antenna elements among the plurality of first antenna elements when viewed from a third direction orthogonal to the first direction and the second direction, the adjacent first antenna elements each include a first radiating element and a second radiating element arranged between the first radiating element and the first ground electrode, the second antenna element includes a third radiating element, the first radiating element, the second radiating element, and the third radiating element are in a flat plate shape, the size of the second radiating element is larger than the size of the first radiating element in the first direction, and the facing distance between the third radiating element and the second ground electrode is shorter than the facing distance between the first radiating element and the first ground electrode.

[0013] Effects of the Invention

[0014] According to the present disclosure, it is possible to prevent a decrease in antenna gain in an antenna module in which a second antenna element including a third radiating element is arranged between adjacent first antenna elements among a plurality of first antenna elements formed by stacking first and second radiating elements of different sizes. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a block diagram of a communication device to which the antenna module according to the first embodiment is applied.

[0016] Figure 2 yes Figure 1 A top view and a side perspective view of the antenna module.

[0017] Figure 3 1 and 2 are a plan view and a side perspective view of the antenna module according to the second embodiment.

[0018] Figure 4 1 and 2 are a plan view and a side perspective view of the antenna module according to the third embodiment.

[0019] Figure 51 and 2 are a plan view and a side perspective view of the antenna module according to the fourth embodiment.

[0020] Figure 6 It is a top view of the antenna module involved in Embodiment 5.

[0021] Figure 7 1 and 2 are a plan view and a side perspective view of the antenna module according to the sixth embodiment. DETAILED DESCRIPTION

[0022] Hereinafter, the embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In addition, in the drawings, the same reference numerals are given to the same or corresponding parts, and their description will not be repeated.

[0023] [Implementation Method 1]

[0024] (Basic structure of communication device)

[0025] Figure 1 This is an example of a block diagram of a communication device 10 to which the antenna module 100 according to Embodiment 1 is applied. The communication device 10 is, for example, a portable terminal such as a mobile phone, a smart phone, or a tablet computer, a personal computer with a communication function, etc. An example of a frequency band of radio waves used by the antenna module 100 according to Embodiment 1 is radio waves in the millimeter wave band with center frequencies such as 28 GHz and 60 GHz, but radio waves in frequency bands other than these can also be applied to the antenna module according to the present disclosure.

[0026] Reference Figure 1 The communication device 10 includes an antenna module 100 and a BBIC 200 constituting a baseband signal processing circuit. The antenna module 100 includes an RFIC 110 as an example of a feeding device, and an antenna device 120. The communication device 10 up-converts the signal transmitted from the BBIC 200 to the antenna module 100 into a high-frequency signal using the RFIC 110, and radiates the signal from the antenna device 120. In addition, the communication device 10 sends the high-frequency signal received by the antenna device 120 to the RFIC 110, performs down-conversion, and processes the signal in the BBIC 200.

[0027] The antenna module 100 is a so-called multi-band antenna module capable of radiating radio waves of two different frequency bands. The antenna device 120 includes antenna elements 151 and 152 .

[0028] Antenna element 151 includes radiating elements 121 and 122. Antenna element 152 includes radiating element 123. In Embodiment 1, radiating elements 121, 122, and 123 are all patch antennas having a flat plate shape. Radiating element 122 radiates radio waves in a first frequency band. Radiating elements 121 and 123 radiate radio waves in a second frequency band. For example, the first frequency band is 60 GHz and the second frequency band is 28 GHz.

[0029] The antenna element 151 is composed of a stacked patch antenna obtained by stacking the radiating element 121 and the radiating element 122. The antenna element 152 is composed of a single radiating element 123. The antenna element 151 and the antenna element 152 are formed on the dielectric substrate 130 (see FIG. 1 ) in the antenna device 120. Figure 2 ) are arranged alternately along one direction.

[0030] exist Figure 1 , an example is shown in which antenna elements 151 and 152 are arranged in a row to form a one-dimensional array. Instead of such an arrangement, antenna elements 151 and 152 may be arranged in a two-dimensional array.

[0031] The RFIC 110 has feeding circuits corresponding to the radiating elements 121 to 123. Specifically, the RFIC 110 includes a feeding circuit 110A corresponding to the radiating element 121, a feeding circuit 110B corresponding to the radiating element 122, and a feeding circuit 110C corresponding to the radiating element 123. In addition, a feeding circuit may be provided for each frequency band of the radiating element. For example, when the radiating element 122 radiates radio waves of a first frequency band (60 GHz) and the radiating elements 121 and 123 radiate radio waves of a second frequency band (28 GHz), one feeding circuit corresponding to the radiating element 122 and one feeding circuit corresponding to the radiating elements 121 and 123 may be provided.

[0032] The feed circuit 110A 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 multiplexer / demultiplexer 116 , a mixer 118 , and an amplifier circuit 119 .

[0033] 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.

[0034] The signal transmitted from the BBIC 200 is amplified by the amplifier circuit 119 and up-converted by the mixer 118. The transmission signal, which is a high-frequency signal after up-conversion, is divided into four by the signal multiplexer / demultiplexer 116 and fed to different radiating elements 121 through four signal paths. 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. In addition, the attenuators 114A to 114D adjust the strength of the transmission signal.

[0035] The reception signals as high frequency signals received by the radiation elements 121 are respectively transmitted through four different signal paths and are multiplexed by the signal multiplexer / demultiplexer 116. The multiplexed reception signals are down-converted by the mixer 118, amplified by the amplifier circuit 119, and transmitted to the BBIC 200.

[0036] The structures of the feed circuits 110B and 110C are the same as those of the feed circuit 110A. Figure 1 The detailed structure of the feeding circuits 110B and 110C is omitted in the figure.

[0037] The RFIC 110 is formed, for example, as a single-chip integrated circuit component including the above-mentioned circuit structure. Alternatively, it can also be formed as a separate integrated circuit component for each feeding circuit. Furthermore, regarding the devices corresponding to each radiating element (switch, power amplifier, low noise amplifier, attenuator, phase shifter), it can also be formed as a single-chip integrated circuit component for each corresponding radiating element.

[0038] (Structure of antenna module)

[0039] Next, use Figure 2 The structure of the antenna module 100 according to the first embodiment will be described in detail. Figure 2 is a diagram showing an antenna module 100 according to Embodiment 1. Figure 2 , the top portion shows a top view of the antenna module 100 ( Figure 2 (A)), the lower part shows a side perspective view ( Figure 2 (B)).

[0040] The antenna module 100 includes an antenna element 151 including the radiating elements 121 and 122 , an antenna element 152 including the radiating element 123 , and the RFIC 110 , and further includes a dielectric substrate 130 , feeder wirings 141 , 142 , and 143 , and ground electrodes GND1 and GND2 .

[0041] In the following description, the normal direction (radiation direction of radio waves) of the dielectric substrate 130 is defined as the Z-axis direction. In addition, in a plane perpendicular to the Z-axis direction, the arrangement direction of the antenna elements 151 and 152 is defined as the X-axis, and the direction orthogonal to the X-axis is defined as the Y-axis. In addition, the positive direction of the Z-axis in each figure is sometimes referred to as the upper side, and the negative direction is sometimes referred to as the lower side.

[0042] The dielectric substrate 130 is, for example, a low temperature co-fired ceramic (LTCC) multilayer substrate, a multilayer resin substrate formed by laminating a plurality of resin layers composed of epoxy, polyimide or other resins, a multilayer resin substrate formed by laminating a plurality of resin layers composed of liquid crystal polymer (LCP) having a lower dielectric constant, a multilayer resin substrate formed by laminating a plurality of resin layers composed of fluorine-based resins, a multilayer resin substrate formed by laminating a plurality of resin layers composed of PET (Polyethylene Terephthalate), or a ceramic multilayer substrate other than LTCC. In addition, the dielectric substrate 130 does not necessarily have to be a multilayer structure, and may be a single-layer substrate.

[0043] The dielectric substrate 130 has a rectangular shape when viewed from the normal direction (Z-axis direction). A ground electrode GND1 is arranged over the entire surface of the dielectric substrate 130 at a position close to the lower surface of the dielectric substrate 130. The ground electrode GND2 is connected to the ground electrode GND1 via a via conductor 170. In the Z-axis direction, the ground electrode GND1 and the ground electrode GND2 face each other. In the dielectric substrate 130, the antenna elements 151 and the antenna elements 152 are alternately arranged at a predetermined pitch in the X-axis direction.

[0044] The antenna element 151 is composed of a stacked patch antenna obtained by stacking the radiation elements 121 and 122 in the Z-axis direction. The antenna element 152 is composed of the radiation element 123. The radiation element 121 of the radiation elements 121 and 122 is arranged at a position close to the upper surface (the surface in the positive direction of the Z-axis) of the dielectric substrate 130. The radiation element 122 is arranged between the radiation element 121 and the ground electrode GND1. When the dielectric substrate 130 is viewed from the normal direction (Z-axis direction), the radiation element 122 overlaps with the radiation element 121. The radiation element 121 is arranged at a position facing the ground electrode GND1 at a distance Da.

[0045] In the first embodiment, when dielectric substrate 130 is viewed from the Z-axis direction, the center of antenna element 152 (radiating element 123 ) is located on a line connecting the centers of adjacent antenna elements 151 (centers of radiating elements 121 , 122 ).

[0046] In the dielectric substrate 130, the distance from the radiating element 123 to the lower surface of the dielectric substrate 130 is the same as the distance from the radiating element 121 to the lower surface of the dielectric substrate 130. In the dielectric substrate 130, the facing distance between the radiating element 121 and the ground electrode GND1 is the same as the facing distance between the radiating element 123 and the ground electrode GND1 (facing distance = Da). The radiating element 123 and the ground electrode GND2 face each other at a distance Db.

[0047] The radiation elements 121 and 123 may be disposed so as to be exposed on the surface of the dielectric substrate 130 , or may be disposed inside the dielectric substrate 130 .

[0048] The radiation elements 122, 121, and 123 are each a flat plate-shaped electrode having a rectangular shape. The size of the radiation element 121 is the same as the size of the radiation element 123. Therefore, the resonance frequency of the radiation element 121 is the same as the resonance frequency of the radiation element 123. The size of the radiation element 122 is larger than the sizes of the radiation elements 121 and 123. More specifically, in the X-axis direction and the Y-axis direction, the size of the radiation element 122 is more than twice the size of the radiation elements 121 and 123. Therefore, the resonance frequency of the radiation elements 121 and 123 is higher than the resonance frequency of the radiation element 122. That is, the frequency band of the radio waves radiated from the radiation elements 121 and 123 is higher than the frequency band of the radio waves radiated from the radiation element 122.

[0049] In the first embodiment, the center frequency of the frequency band of the radiating elements 121 and 123 is 28 GHz, and the center frequency of the frequency band of the radiating element 122 is 60 GHz.

[0050] The ground electrode GND2 is a flat plate-shaped electrode having a rectangular shape similarly to the radiation elements 121, 122, and 123. The size of the ground electrode GND2 in the X-axis direction is the same as the size of the radiation elements 121 and 123 in the X-axis direction. The size of the ground electrode GND2 in the Y-axis direction is larger than the size of the radiation elements 121 and 123 in the Y-axis direction, and is the same as the size of the radiation element 122 in the Y-axis direction.

[0051] High-frequency signals are supplied from the RFIC 110 to the radiating elements 121, 122, and 123 via the feed wirings 141, 142, and 143, respectively. The feed wiring 141 extends from the RFIC 110 through the ground electrode GND1 and the radiating element 122 to be connected to the feed point SP1 of the radiating element 121. The feed wiring 142 extends from the RFIC 110 through the ground electrode GND1 to be connected to the feed point SP2 of the radiating element 122. The feed wiring 143 extends from the RFIC 110 through the ground electrodes GND1 and GND2 to be connected to the feed point SP3 of the radiating element 123.

[0052] The feeding point SP1 is offset in the positive direction of the X-axis relative to the center of the radiating element 121. The feeding point SP2 is offset in the positive direction of the X-axis relative to the center of the radiating element 122. The feeding point SP3 is offset in the positive direction of the X-axis relative to the center of the radiating element 123. Thus, radio waves with the X-axis direction as the polarization direction are radiated from the radiating elements 122, 121, and 123, respectively.

[0053] The RFIC 110 is mounted on the lower surface of the dielectric substrate 130 via solder bumps 160. In addition, the RFIC 110 may also be connected to the dielectric substrate 130 using a multi-pole connector instead of using solder connection to connect to the dielectric substrate 130.

[0054] Generally, when a plurality of patch antennas are arranged to form an array, the optimal spacing (center-to-center distance) between the patch antennas is set to about 0.4 to 0.8 times the wavelength λ0 in space. If the patch antennas are arranged at a spacing that is not the optimal spacing, the antenna gain may be reduced or grating lobes may be generated, thereby reducing the antenna gain. Therefore, even when stacked patch antennas such as antenna element 151 are arranged in an array, it is important to achieve the optimal spacing.

[0055] However, in order to support multiple frequency bands, stacked patch antennas are formed by stacking multiple radiating elements of different sizes. The wavelength of the radio waves radiated by the relatively small radiating elements is shorter than the wavelength of the radio waves radiated by the relatively large radiating elements. Therefore, the spacing most suitable for the radiating elements with smaller sizes is inconsistent with the spacing most suitable for the radiating elements with larger sizes. Therefore, it is difficult to optimize the spacing between adjacent stacked patch antennas.

[0056] When the radiating element that radiates radio waves with relatively short wavelengths is called a high-frequency patch, and the radiating element that radiates radio waves with relatively long wavelengths is called a low-frequency patch, a significant reduction in antenna gain generally occurs in the area where "frequency of the high-frequency patch ≥ frequency of the low-frequency patch × 1.8" holds.

[0057] Therefore, in Embodiment 1, the antenna element 152 including the radiation element 123 is arranged between adjacent antenna elements 151. Figure 2 As shown in the figure, the following structure is realized: in the dielectric substrate 130, the radiating elements 121 and 123 constituting the high-frequency patch are alternately arranged at a pitch that is optimal for the high-frequency patch, and the radiating element 122 constituting the low-frequency patch is arranged at a pitch that is optimal for the low-frequency patch with the antenna element 152 (radiating element 123) sandwiched therebetween. According to this structure, it is possible to optimize the pitch between the radiating elements 121 and 123 constituting the high-frequency patch and optimize the pitch between the radiating elements 122 and 122 constituting the low-frequency patch.

[0058] Furthermore, in the first embodiment, the ground electrode GND2 is provided on the dielectric substrate 130 at a position closer to the radiating element 123 than the ground electrode GND1 so as to face the radiating element 123. That is, the facing distance Db between the radiating element 123 and the ground electrode GND2 is shorter than the facing distance Da between the radiating element 121 and the ground electrode GND1 (distance Db<distance Da). In the present embodiment, it can be said that a structure is adopted in which the position of the ground electrode facing the radiating element 123 is moved closer to the radiating element 123 side from the ground electrode GND1. Therefore, compared with a structure in which the radiating element 123 faces the ground electrode GND1 on the lower surface side of the dielectric substrate 130 without providing the ground electrode GND2, it is possible to prevent the generation of a high-order mode surface acoustic wave in the radiating element 123. As a result, it is possible to prevent the antenna gain of the entire antenna module 100 from being adversely affected by the reduction of the antenna gain in the front direction of the radiation direction of the radiating element 123.

[0059] In Embodiment 1, the facing distance between the radiating element 121 and the ground electrode GND1 is the same as the facing distance between the radiating element 123 and the ground electrode GND1. However, the facing distance between the radiating element 121 and the ground electrode GND1 may be different from the facing distance between the radiating element 123 and the ground electrode GND1. For example, one of the radiating element 121 and the radiating element 123 may be arranged at a position closer to the upper surface of the dielectric substrate 130 than the other. That is, when the dielectric substrate 130 is viewed from the Y-axis direction, the plurality of high-frequency patches composed of the radiating elements 121 and 123 may not be arranged on the same plane.

[0060] When the dielectric substrate 130 is viewed from the Y-axis direction, the radiating elements 121 may not be arranged on the same plane. When the dielectric substrate 130 is viewed from the Y-axis direction, the radiating elements 123 may not be arranged on the same plane.

[0061] In Embodiment 1, when the dielectric substrate 130 is viewed from the Y-axis direction, the facing distance between the radiating element 122 and the ground electrode GND1 is the same as the facing distance between the ground electrode GND2 and the ground electrode GND1. However, in the present disclosure, the facing distance between the radiating element 122 and the ground electrode GND1 may be greater than the facing distance between the ground electrode GND2 and the ground electrode GND1.

[0062] In the first embodiment, the ground electrode GND2 is connected to the ground electrode GND1 through the via conductor 170. However, the ground electrode GND2 may be formed by a portion of the ground electrode GND1 facing the radiation element 123. In this case, the portion of the ground electrode GND1 facing the radiation element 123 is made thicker in the Z-axis direction than other portions, thereby achieving Figure 2 The ground electrode GND2 and the radiation element 123 are shown to be at a facing distance Db.

[0063] In Embodiment 1, when dielectric substrate 130 is viewed from the Z-axis direction, the center of antenna element 152 (radiating element 123) is located on a line connecting the centers of adjacent antenna elements 151 (centers of radiating elements 121 and 122). This means that antenna element 152 is disposed between adjacent antenna elements 151.

[0064] However, in order to arrange the antenna element 152 between adjacent antenna elements 151, it is not necessary to position the center of the antenna element 152 (radiating element 123) on the line connecting the centers of the adjacent antenna elements 151 (centers of the radiating elements 121, 122). The center of the antenna element 152 (radiating element 123) may be located off the line. In the present disclosure, when viewed from the Y-axis direction, the antenna element 152 may be arranged between adjacent antenna elements 151 among the plurality of antenna elements 151.

[0065] In the first embodiment, the ground electrode GND1 is an example of a first ground electrode, the ground electrode GND2 is an example of a second ground electrode, the antenna element 151 is an example of a first antenna element, and the antenna element 152 is an example of a second antenna element.

[0066] In Embodiment 1, the X-axis direction is an example of the first direction, the Z-axis direction is an example of the second direction, and the Y-axis direction is an example of the third direction. In Embodiment 1, 28 GHz, which is the center frequency of the frequency band of the radiation element 122, is an example of the first frequency band, and 60 GHz, which is the center frequency of the frequency band of the radiation elements 121 and 123, is an example of the second frequency band on the high frequency side compared to the first frequency band.

[0067] [Implementation Method 2]

[0068] Figure 3 are the top view and side perspective view of the antenna module 100A according to Embodiment 2. In Figure 3 , the top view of the antenna module 100A is shown in the upper part ( Figure 3 (A) of Figure 3 ), and the side perspective view is shown in the lower part (

[0069] The antenna module 100A according to Embodiment 2 has a different shape of the ground electrode facing the radiation element 123 compared to the antenna module 100 according to Embodiment 1. In the antenna module 100A, the radiation element 123 faces the ground electrode GND21. The ground electrode GND21 of the antenna module 100A has a smaller size in the X-axis direction compared to the ground electrode GND2 of the antenna module 100. More specifically, in the X-axis direction, the size of the ground electrode GND21 is smaller than the size of the radiation element 123. As Figure 3 shown, when the size of the ground electrode GND21 in the X-axis direction is set as La1 and the size of the radiation element 123 in the X-axis direction is set as Lb1, the relationship La1 < Lb1 holds.

[0070] As Figure 3 shown, radiation elements 122 that form a part of the antenna element 151 are arranged on both sides of the ground electrode GND21. By making the size of the ground electrode GND21 in the X-axis direction smaller than the size of the ground electrode GND2 according to Embodiment 1 in the X-axis direction, the influence on the radio wave radiation of the radiation element 122 can be reduced. As a result, it is possible to suppress the following situation: the antenna gain of the radiation element 122 that functions as a low-frequency patch in the antenna element 151 is reduced due to the ground electrode GND21 provided between adjacent antenna elements 151.

[0071] The structure of the antenna module 100A is the same as the structure of the antenna module 100 except for the ground electrode GND21. Therefore, the detailed description of the other structures of the antenna module 100A will not be repeated here.

[0072] [Embodiment 3]

[0073] Figure 4 are the top view and side perspective view of the antenna module 100B according to Embodiment 3. In Figure 4 , the top view of the antenna module 100B is shown in the upper part ( Figure 4 (A) of Figure 4 ), and the side perspective view is shown in the lower part (

[0074] As described in Embodiment 2, by reducing the size of the ground electrode facing the radiating element 123 in the X-axis direction like the ground electrode GND21, it is possible to suppress the reduction in the antenna gain of the radiating element 122. However, the surface area of ​​the ground electrode GND21 when the dielectric substrate 130 is viewed from the Z-axis direction becomes smaller than the surface area of ​​the ground electrode GND2 when the dielectric substrate 130 is viewed from the Z-axis direction. As a result, the antenna gain of the radiating element 123 is reduced.

[0075] Therefore, similarly to the antenna module 100A according to the second embodiment, the antenna module 100B according to the third embodiment reduces the size of the ground electrode facing the radiating element 123 in the X-axis direction, while increasing the size of the ground electrode in the Y-axis direction. More specifically, when the size of the ground electrode GND22 in the Y-axis direction is La2 and the size of the radiating element 122 in the Y-axis direction is Lb2, the relationship La2>Lb2 holds. Thus, in the third embodiment, the size of the ground electrode GND22 facing the radiating element 123 in the Y-axis direction is larger than the size of the radiating element 122.

[0076] According to Embodiment 3, the antenna gain of the radiating element 123 can be improved by increasing the surface area of ​​the ground electrode GND22 compared to the surface area of ​​the ground electrode GND21 while suppressing the adverse effect of the ground electrode GND22 on the radio wave radiation of the radiating element 122 .

[0077] The structure of the antenna module 100B is the same as that of the antenna module 100 except for the ground electrode GND22. Therefore, detailed description of the other structures of the antenna module 100B will not be repeated here.

[0078] [Implementation Method 4]

[0079] Figure 5 1 is a top view and a side perspective view of an antenna module 100C according to Embodiment 4. Figure 5 , the top portion shows a top view of the antenna module 100C ( Figure 5 (A)), the lower part shows a side perspective view ( Figure 5 (B)). The antenna module 100C includes an RFIC 110 and an antenna device 120C.

[0080] The antenna module 100C according to the fourth embodiment is characterized in that the via conductor 170 connected to the ground electrode facing the radiating element 123 is located in the antenna module 100C as compared to the antenna module 100 according to the first embodiment. In the antenna module 100C, the radiating element 123 faces the ground electrode GND23. The ground electrode GND23 is connected to the via conductor 170 at the connection portion CP1.

[0081] like Figure 5 As shown, when the size of the radiation element 122 in the X-axis direction is a and the distance between the end of the ground electrode GND23 and the connection portion CP1 in the X-axis direction is b, there is a relationship of "b=a / 2" between the size a and the distance b.

[0082] In Embodiment 4, by configuring in this way, the isolation between the adjacent radiating elements (low-frequency patches) 122 via the radiating element 123 is ensured. When the radiating element 122 is excited by radio wave radiation, the ground electrode GND1 arranged opposite to the radiating element 122 is also excited, and an excitation signal is generated in the ground electrode GND1. This excitation signal affects the antenna gain of other radiating elements 122 opposite to the ground electrode GND1.

[0083] Therefore, in the fourth embodiment, the ground electrode GND23 disposed between adjacent radiating elements 122 functions as a shielding wall for shielding the excitation signal. Generally, an excitation signal having a waveform determined by the wavelength λ of the radio wave radiated from the radiating element 122 is generated in the ground electrode GND1 by the excitation of the radiating element 122. The excitation signal is transmitted from the connection portion CP1 to the ground electrode GND23 through the ground electrode GND1 and the via conductor 170. The excitation signal transmitted to the ground electrode GND23 is folded back at the end of the ground electrode GND23 in the X-axis direction and returns to the connection portion CP1. Therefore, in the ground electrode GND23, the excitation signal traveling from the connection portion CP1 to the end of the ground electrode GND23 interferes with the excitation signal returning from the end of the ground electrode GND23 to the connection portion CP1.

[0084] In the fourth embodiment, the distance b from the connection portion CP1 to the end of the ground electrode GND23 is set to "1 / 2" of the dimension a of the radiation element 122 in the X-axis direction. The wavelength of the radio wave radiated from the radiation element 122 is "1 / 2" of the dimension a of the radiation element 122. Therefore, the distance b from the connection portion CP1 to the end of the ground electrode GND23 is equivalent to "1 / 4" of the wavelength of the radio wave radiated from the radiation element 122.

[0085] When the distance from the connection portion CP1 to the end of the ground electrode GND23 is set in this way, the phase of the excitation signal returning from the end of the ground electrode GND23 to the connection portion CP1 becomes a phase obtained by inverting the phase of the excitation signal traveling from the connection portion CP1 to the end of the ground electrode GND23. Therefore, the excitation signal traveling from the connection portion CP1 to the end of the ground electrode GND23 and the excitation signal returning from the end of the ground electrode GND23 to the connection portion CP1 cancel each other. As a result, it is possible to prevent the excitation signal generated in the ground electrode GND1 due to the excitation of one of the adjacent radiation elements 122 across the ground electrode GND23 from being transmitted to the other radiation element 122.

[0086] Thus, in Embodiment 4, the ground electrode GND23 disposed between adjacent radiating elements 122 functions as a shielding wall for shielding the excitation signal. Thus, the isolation between adjacent radiating elements 122 sandwiching the radiating element 123 is ensured. As a result, the antenna gain of the radiating element 122 can be improved.

[0087] In addition, an example is described here in which the distance b between the end of the ground electrode GND23 and the connection portion CP1 in the X-axis direction is set to "1 / 2" of the dimension a of the radiation element 122 in the X-axis direction. In this case, the distance b is equivalent to "1 / 4" of the wavelength of the radio wave radiated from the radiation element 122. That is, in the fourth embodiment, by setting the distance b to "1 / 4" of the wavelength of the radio wave radiated from the radiation element 122, the excitation signal generated in the GND1 is cancelled.

[0088] However, the effect of canceling or reducing the excitation signal generated in GND1 is not obtained only when the distance b is set to "1 / 4" of the wavelength of the radio wave radiated from the radiation element 122. For example, when the distance b is set in the range of "1 / 8" or more and "3 / 8" or less of the wavelength of the radiation element 122, the effect of canceling or reducing the excitation signal generated in GND1 can be achieved. In other words, when the distance b is set in the range of "1 / 4" or more and "3 / 4" or less of the dimension a of the radiation element 122, the effect of canceling or reducing the excitation signal generated in GND1 can be achieved. Therefore, the distance b between the end of the ground electrode GND23 in the X-axis direction and the connection portion CP1 can be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be set to be

[0089] The structure of the antenna module 100C is the same as that of the antenna module 100 except for the ground electrode GND23. Therefore, detailed description of the other structures of the antenna module 100C will not be repeated here.

[0090] [Implementation method 5]

[0091] Figure 6 1 is a top view of an antenna module 100D according to Embodiment 5. The antenna module 100D includes an RFIC 110 and an antenna device 120D. Figure 6 In the figure, the illustration of RFIC 110 is omitted.

[0092] In the antenna module 100D according to the fifth embodiment, the antenna elements 151 and 152 are arranged in a two-dimensional array in the X-axis direction and the Y-axis direction. Thus, in the fifth embodiment, the adjacent antenna elements 151 and the antenna elements 152 arranged between the adjacent antenna elements 151 are arranged in an array along the X-axis direction and the Y-axis direction on the dielectric substrate 130. By arranging the antenna elements 151 and 152 in a two-dimensional array, the total amount of energy as an array antenna can be increased.

[0093] Furthermore, in the antenna module 100D, the ground electrode GND24 facing each radiating element 123 is integrally configured as supplementarily shown in the dotted-line frame. More specifically, the ground electrode GND24 extends from a position facing one of the radiating elements 123 adjacent in the X-axis direction to a position facing the other, and extends from a position facing one of the radiating elements 123 adjacent in the Y-axis direction to a position facing the other.

[0094] The antenna module 100D has the following structure: Figure 4 In the antenna module 100B shown, the antenna elements 151 and 152 are arranged in a two-dimensional array, and on this basis, each ground electrode GND22 is further extended in the longitudinal direction to connect each ground electrode GND22. Therefore, the surface area of ​​the ground electrode GND24 is further increased compared to the surface area of ​​the ground electrode GND22. As a result, according to the antenna module 100D involved in the fifth embodiment, the antenna gain of each radiating element 123 can be further improved.

[0095] Furthermore, when viewed from the Z-axis direction, the positions of the antenna elements 151 and 152 may be arranged in a checkered pattern. For example, in the first, second, third, ... columns in the X-axis direction, when the antenna elements 151 and 152 are alternately arranged at a certain pitch, the positions of the antenna elements 151 at the beginning of the odd-numbered columns in the Y-axis direction may be aligned, while the positions of the antenna elements 151 at the beginning of the even-numbered columns in the Y-axis direction may be offset from the positions of the antenna elements 151 at the beginning of the odd-numbered columns in the Y-axis direction.

[0096] The structure of the antenna module 100D is the same as that of the antenna module 100 except that the antenna elements 151 and 152 are arranged in a two-dimensional array and the ground electrode GND24. Therefore, detailed description of other structures of the antenna module 100D will not be repeated here.

[0097] [Implementation Method 6]

[0098] Figure 7 1 is a top view and a side perspective view of an antenna module 100E according to Embodiment 6. Figure 7 , the top portion shows a top view of the antenna module 100E ( Figure 7 (A)), the lower part shows a side perspective view ( Figure 7 (B)). The antenna module 100E includes an RFIC 110 and an antenna device 120E.

[0099] The antenna module 100E according to the sixth embodiment differs from the antenna module 100 according to the first embodiment in the number of radiating elements stacked in the antenna elements adjacent to each other across the antenna element 152. In the antenna module 100E, the antenna element 151A constituting a three-layer stacked patch antenna is used as the antenna element adjacent to each other across the antenna element 152.

[0100] like Figure 7 As shown, in the antenna element 151A, in addition to the radiation elements 121 and 122 stacked as in the antenna element 151 , a radiation element 124 having a size larger than that of the radiation element 122 is stacked.

[0101] A high-frequency signal is supplied from the RFIC 110 to the radiating element 124 via the feeding wiring 144. The feeding wiring 144 passes through the ground electrode GND1 from the RFIC 110 and is connected to the feeding point SP4 of the radiating element 124. The feeding point SP4 is offset in the positive direction of the X axis with respect to the center of the radiating element 124. The radiating element 124 radiates an electric wave having a polarization direction in the X axis direction and a frequency band lower than that of the radiating element 122.

[0102] According to the sixth embodiment, it is possible to provide an antenna module 100E supporting three bands.

[0103] In Embodiment 6, the radiation element 124 is an example of a fourth radiation element. Figure 7As shown, in the X-axis direction, the size of the radiating element 124 is larger than that of the radiating element 121 and is different from that of the radiating element 122. Here, as the antenna element 151A, an example in which the radiating element 124 is provided between the radiating elements 121 and 122 and the ground electrode GND1 is described. However, the antenna element 151A may be configured by providing a radiating element having a lower frequency band than the frequency band of the radiating element 121 and a higher frequency band than the frequency band of the radiating element 122 between the radiating element 121 and the radiating element 122. In addition, instead of the stacked patch antenna having a three-layer structure, a stacked patch antenna having a four-layer structure or more may be used as the antenna element 151A.

[0104] The structure of the antenna module 100E, except for the antenna element 151A, is the same as that of the antenna module 100. Therefore, detailed description of the other structures of the antenna module 100E will not be repeated here.

[0105] In the present disclosure, it is planned to arbitrarily combine any two or three or more of the embodiments described above.

[0106] [Way]

[0107] It will be understood by those skilled in the art that the above-mentioned embodiments are specific examples of the following aspects.

[0108] (Item 1) An antenna module according to one embodiment includes: a dielectric substrate; a first ground electrode and a second ground electrode arranged on the dielectric substrate; a plurality of first antenna elements arranged along a first direction on the dielectric substrate; and a second antenna element arranged on the dielectric substrate, wherein the plurality of first antenna elements face the first ground electrode in a second direction different from the first direction, the second antenna element faces the second ground electrode in the second direction, the second antenna element is arranged between adjacent first antenna elements among the plurality of first antenna elements when viewed from a third direction orthogonal to the first direction and the second direction, the adjacent first antenna elements each include a first radiating element and a second radiating element arranged between the first radiating element and the first ground electrode, the second antenna element includes a third radiating element, the first radiating element, the second radiating element, and the third radiating element are in a flat plate shape, the size of the second radiating element is larger than the size of the first radiating element in the first direction, and the facing distance between the third radiating element and the second ground electrode is shorter than the facing distance between the first radiating element and the first ground electrode.

[0109] (Second Item) In the antenna module of the first item, in the first direction, a size of the second ground electrode is smaller than a size of the third radiation element.

[0110] (Item 3) In the antenna module of Item 1 or Item 2, in the third direction, a size of the second ground electrode is larger than a size of the second radiation element.

[0111] (Item 4) In the antenna module of any one of items 1 to 3, in the second direction, the first ground electrode and the second ground electrode are facing each other, and when observed from the third direction, the facing distance between the second radiation element and the first ground electrode is greater than the facing distance between the second ground electrode and the first ground electrode.

[0112] (Item 5) In the antenna module of any one of Items 1 to 4, a plurality of second antenna elements are arranged on a dielectric substrate, and adjacent first antenna elements and second antenna elements arranged between adjacent first antenna elements are arranged in an array along a first direction on the dielectric substrate.

[0113] (Item 6) In the antenna module of any one of Items 1 to 4, a plurality of second antenna elements are arranged on a dielectric substrate, and adjacent first antenna elements and second antenna elements arranged between adjacent first antenna elements are arranged in an array along a third direction on the dielectric substrate.

[0114] (Item 7) In the antenna module of Item 5, adjacent first antenna elements and second antenna elements disposed between adjacent first antenna elements are arranged in an array along a third direction on the dielectric substrate, and the second ground electrode extends from a position facing one of the second antenna elements adjacent in the first direction to a position facing the other, and extends from a position facing one of the second antenna elements adjacent in the third direction to a position facing the other.

[0115] (Item 8) In the antenna module of any one of items 1 to 7, in the second direction, the first ground electrode and the second ground electrode are opposite to each other, the second ground electrode has a connection portion connected to the first ground electrode through a via conductor, and the distance between the end portion of the second ground electrode in the first direction and the connection portion is greater than 1 / 4 and less than 3 / 4 of the size of the second radiation element in the first direction.

[0116] (Item 9) In the antenna module of any one of Items 1 to 8, a distance between the first radiating element and the first ground electrode in the second direction is the same as a distance between the third radiating element and the first ground electrode in the second direction.

[0117] (Item 10) In the antenna module according to any one of Items 1 to 9, a size of the second radiating element is at least twice a size of the first radiating element in the first direction or the third direction.

[0118] (Item 11) In the antenna module according to any one of Items 1 to 10, in the first direction, a size of the first radiation element is the same as a size of the third radiation element.

[0119] (Item 12) In the antenna module of any one of Items 1 to 11, the second radiating element radiates radio waves in a first frequency band, and the first radiating element and the third radiating element radiate radio waves in a second frequency band on the higher frequency side than the first frequency band.

[0120] (Item 13) In the antenna module of any one of items 1 to 12, there is also a fourth radiating element, which is opposite to the first ground electrode and is arranged between the first radiating element and the first ground electrode. In the first direction, the size of the fourth radiating element is larger than the size of the first radiating element and different from the size of the second radiating element.

[0121] (Item 14) A communication device according to another aspect includes the antenna module according to any one of Items 1 to 13.

[0122] The embodiments disclosed this time should be considered in all respects as illustrative and non-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.

[0123] Description of Reference Numerals

[0124] 10: communication device; 100, 100A~100E: antenna module; 110: RFIC; 110A~110C: feeding circuit; 111A~111D, 113A~113D, 117: switch; 112AR~112DR: low noise amplifier; 112AT~112DT: power amplifier; 114A~114D: attenuator; 115A~115D: phase shifter; 116: signal combiner / demultiplexer ; 118: mixer; 119: amplifier circuit; 120, 120A~120E: antenna device; 121~124: radiation element; 130: dielectric substrate; 141~144: feeding wiring; 151, 151A, 152: antenna element; 160: solder bump; 200: BBIC; CP1: connection point; GND1, GND2, GND21~GND24: ground electrodes; SP1~SP4: feeding point.

Claims

1. An antenna module, comprising: Dielectric substrate; a first ground electrode and a second ground electrode disposed on the dielectric substrate; A plurality of first antenna elements arranged along a first direction on the dielectric substrate; and a second antenna element disposed on the dielectric substrate, in, The plurality of first antenna elements face the first ground electrode in a second direction different from the first direction, the second antenna element faces the second ground electrode in the second direction, When viewed from a third direction orthogonal to the first direction and the second direction, the second antenna element is arranged between adjacent first antenna elements among the plurality of first antenna elements. Each of the adjacent first antenna elements includes a first radiation element and a second radiation element arranged between the first radiation element and the first ground electrode, The second antenna element comprises a third radiating element, The first radiation element, the second radiation element and the third radiation element are in the shape of a flat plate, In the first direction, the size of the second radiation element is larger than the size of the first radiation element, The facing distance between the third radiation element and the second ground electrode is shorter than the facing distance between the first radiation element and the first ground electrode.

2. The antenna module according to claim 1, wherein: In the first direction, a size of the second ground electrode is smaller than a size of the third radiation element.

3. The antenna module according to claim 1 or 2, wherein: In the third direction, a size of the second ground electrode is larger than a size of the second radiation element.

4. The antenna module according to any one of claims 1 to 3, wherein: In the second direction, the first ground electrode faces the second ground electrode. When viewed from the third direction, a facing distance between the second radiating element and the first ground electrode is greater than or equal to a facing distance between the second ground electrode and the first ground electrode.

5. The antenna module according to any one of claims 1 to 4, wherein: A plurality of the second antenna elements are arranged on the dielectric substrate, The adjacent first antenna elements and the second antenna elements disposed between the adjacent first antenna elements are arranged in an array along the first direction on the dielectric substrate.

6. The antenna module according to any one of claims 1 to 4, wherein: A plurality of the second antenna elements are arranged on the dielectric substrate, The adjacent first antenna elements and the second antenna elements disposed between the adjacent first antenna elements are arranged in an array along the third direction on the dielectric substrate.

7. The antenna module according to claim 5, wherein: The adjacent first antenna elements and the second antenna elements disposed between the adjacent first antenna elements are arranged in an array along the third direction on the dielectric substrate. The second ground electrode extends from a position facing one of the second antenna elements adjacent in the first direction to a position facing the other, and extends from a position facing one of the second antenna elements adjacent in the third direction to a position facing the other.

8. The antenna module according to any one of claims 1 to 7, wherein: In the second direction, the first ground electrode faces the second ground electrode. The second ground electrode has a connection portion connected to the first ground electrode through a via conductor. A distance between an end portion of the second ground electrode in the first direction and the connection portion is greater than or equal to 1 / 4 and less than or equal to 3 / 4 of a size of the second radiation element in the first direction.

9. The antenna module according to any one of claims 1 to 8, wherein: A distance between the first radiation element and the first ground electrode in the second direction is the same as a distance between the third radiation element and the first ground electrode in the second direction.

10. The antenna module according to any one of claims 1 to 9, wherein: In the first direction or the third direction, a size of the second radiation element is more than twice a size of the first radiation element.

11. The antenna module according to any one of claims 1 to 10, wherein: In the first direction, a size of the first radiation element is the same as a size of the third radiation element.

12. The antenna module according to any one of claims 1 to 11, wherein: The second radiation element radiates radio waves in a first frequency band, The first radiating element and the third radiating element radiate radio waves in a second frequency band located on a higher frequency side than the first frequency band.

13. The antenna module according to any one of claims 1 to 12, wherein: further comprising a fourth radiating element, the fourth radiating element being opposite to the first ground electrode and being arranged between the first radiating element and the first ground electrode, In the first direction, a size of the fourth radiation element is larger than a size of the first radiation element and different from a size of the second radiation element.

14. A communication device, The antenna module according to any one of claims 1 to 13 is mounted thereon.

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