Antenna module and communication device

Abstract

An antenna module is provided with: a substrate including a first dielectric layer and a second dielectric layer having a dielectric constant different from that of the first dielectric layer; a first antenna that is provided in the first dielectric layer and transmits and receives a signal of a first frequency band; a second antenna that is provided on the second dielectric layer and that transmits and receives a signal in a second frequency band that is a frequency band lower than the first frequency band; and a high-frequency circuit provided on the substrate and electrically connected to the first antenna.

Description

[0001] This application is a divisional application of the invention patent application with national application number 201980045591.5, date of entry into the Chinese national phase on January 6, 2021, and invention name “Antenna Module and Communication Device”. Technical Field

[0002] The invention relates to an antenna module and a communication device. Background Art

[0003] Patent document 1 describes an antenna for transmitting and receiving signals of two different frequencies. In the antenna of Patent document 1, dielectric substrates with different dielectric constants are provided on both sides of a ground conductor plate, and antenna elements of different sizes are formed on each dielectric substrate. A common metal plate is provided to short-circuit the ground conductor plate and the two antenna elements, and an antenna power supply line is provided in each dielectric substrate.

[0004] Patent Document 1: Japanese Patent Application Laid-Open No. 11-289215

[0005] In the antenna module, it is necessary to connect the antenna to an external RFIC. However, in Patent Document 1, the RFIC is not provided on a dielectric substrate. Therefore, in the structure of Patent Document 1, in the case of an antenna module that transmits and receives signals in the millimeter wave band and the microwave band, the power supply line connecting the millimeter wave band antenna and the external RFIC may become longer. Therefore, in the transmission and reception of signals in the millimeter wave band, the attenuation of the signal caused by the wiring sometimes increases. Summary of the invention

[0006] An object of the present invention is to provide an antenna module and a communication device that can transmit and receive signals of a plurality of different frequencies and can suppress an increase in the attenuation of a signal transmitted between a high-frequency circuit and an antenna.

[0007] An antenna module according to one embodiment of the present invention comprises: a substrate including a first dielectric layer and a second dielectric layer, the second dielectric layer having a dielectric constant different from that of the first dielectric layer; a first antenna disposed on the first dielectric layer for transmitting and receiving signals in a first frequency band; a second antenna disposed on the second dielectric layer for transmitting and receiving signals in a second frequency band which is a frequency band lower than the first frequency band; and a high-frequency circuit disposed on the substrate and electrically connected to the first antenna.

[0008] A communication device according to one embodiment of the present invention comprises: the antenna module; a motherboard; a millimeter wave circuit provided on the motherboard and connected to the antenna module; and a microwave circuit provided on the motherboard and connected to the antenna module.

[0009] According to the antenna module and the communication device of the present invention, it is possible to transmit and receive signals of a plurality of different frequencies, and it is possible to suppress an increase in the attenuation of the signal transmitted between the high-frequency circuit and the antenna. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 is a top view of an antenna module according to an embodiment.

[0011] Figure 2 is a bottom view of the antenna module according to the embodiment.

[0012] Figure 3 It is along Figure 1 Cross-sectional view along line III-III'.

[0013] Figure 4 is a cross-sectional view of an antenna module according to a first modification.

[0014] Figure 5 is a cross-sectional view of an antenna module according to a second modification.

[0015] Figure 6 is a cross-sectional view of an antenna module according to a third modified example.

[0016] Figure 7 is a cross-sectional view of an antenna module according to a fourth modified example.

[0017] Figure 8 FIG. 1 is a bottom view of an antenna module according to a fifth modification.

[0018] Fig. 9 is a cross-sectional view of an antenna module according to a fifth modification.

[0019] Fig.10 FIG. 1 is a bottom view of an antenna module according to a sixth modification.

[0020] Fig.11 is a cross-sectional view of an antenna module according to a sixth modification.

[0021] Fig.12 It is a block diagram showing a configuration of a communication device including an antenna module according to an embodiment. DETAILED DESCRIPTION

[0022] Hereinafter, the implementation of the antenna module and the communication device of the present invention is described in detail based on the accompanying drawings. In addition, the present invention is not limited to this implementation. Each implementation is an example, and of course, partial replacement or combination of the structures shown in different implementations can be performed. In the first variant and thereafter, the description of matters shared with the implementation is omitted, and only the differences are described. In particular, the same effects produced by the same structure are not mentioned in sequence in each implementation.

[0023] (Implementation Method)

[0024] Figure 1 is a top view of an antenna module according to an embodiment. Figure 2 is a bottom view of the antenna module according to the embodiment. Figure 3 It is along Figure 1 The cross-sectional view of the line III-III'. Figures 1 to 3 As shown, the antenna module 1 includes a substrate 2 , a first antenna 3 , a second antenna 4 , and a high-frequency circuit 5 .

[0025] The antenna module 1 of the present embodiment is a high-frequency module with an antenna installed with a high-frequency circuit 5. The antenna module 1, for example, transmits and receives signals from the quasi-millimeter wave band to the millimeter wave band above 24 GHz and below 75 GHz, and transmits and receives signals in the microwave band below 10 GHz. Signals from the quasi-millimeter wave band to the millimeter wave band include signals in the 28 GHz band, the 39 GHz band, and the 60 GHz band, such as those used in the fifth-generation cellular system and the 60 GHz band Wi-Fi (11ad system). Signals in the microwave band are used in cellular systems, 2.4 GHz / 5 GHz band Wi-Fi, Bluetooth (registered trademark), GPS, NFC, etc. In the following description, the frequency band from the quasi-millimeter wave band to the millimeter wave band will be represented as the millimeter wave band.

[0026] like Figure 3 As shown, the substrate 2 has a first dielectric layer 21 and a second dielectric layer 22. The first dielectric layer 21 and the second dielectric layer 22 are respectively multilayer substrates. The second dielectric layer 22 has a dielectric constant different from the dielectric constant of the first dielectric layer 21. Specifically, the dielectric constant of the second dielectric layer 22 is higher than the dielectric constant of the first dielectric layer 21. As materials for the first dielectric layer 21 and the second dielectric layer 22, any one or more of low temperature co-fired ceramics (hereinafter referred to as LTCC (Low Temperature Co-fired Ceramics)), glass epoxy resin, liquid crystal polymer, fluororesin, polyimide resin, etc. can be used respectively. Among these materials, LTCC has the highest dielectric constant, and the dielectric constant decreases in the order of glass epoxy resin, liquid crystal polymer, and fluororesin.

[0027] The substrate 2 can combine the first dielectric layer 21 and the second dielectric layer 22 made of different types of materials. For example, LTCC is used as the material of the second dielectric layer 22 with a high dielectric constant, and liquid crystal polymer is used as the material of the first dielectric layer 21 with a low dielectric constant. The combination of materials used for the first dielectric layer 21 and the second dielectric layer 22 can be appropriately changed. In this way, by making the first dielectric layer 21 and the second dielectric layer 22 respectively made of different types of materials, the dielectric constant of the first dielectric layer 21 and the dielectric constant of the second dielectric layer 22 can be easily made different.

[0028] In addition, the first dielectric layer 21 and the second dielectric layer 22 can also be made of the same type of material among the above-mentioned materials, and the composition can be different. For example, as the material of the first dielectric layer 21, a high dielectric constant LTCC is used, and as the material of the second dielectric layer 22, a low dielectric constant LTCC is used. Regarding the high dielectric constant LTCC and the low dielectric constant LTCC, for example, the composition and content of the ceramic material are different. Therefore, as the first dielectric layer 21 and the second dielectric layer 22, the same type of material is used, and the manufacture of the antenna module 1 is easy.

[0029] like Figure 3 As shown in FIG. 1 , the first dielectric layer 21 and the second dielectric layer 22 are arranged to overlap in the thickness direction. Figure 1 and Figure 2 As shown, in a plan view, the area of ​​the first dielectric layer 21 is larger than the area of ​​the second dielectric layer 22. Here, the substrate 2 has a first main surface S1, a second main surface S2, and a third main surface S3. The first main surface S1 is a surface of the first dielectric layer 21 on the opposite side to the surface on which the second dielectric layer 22 is provided. The second main surface S2 is a surface of the second dielectric layer 22 on the opposite side to the surface on which the first dielectric layer 21 is provided. The third main surface S3 is a surface of the first dielectric layer 21 on the opposite side to the first main surface S1. The portion of the third main surface S3 where the second dielectric layer 22 is not provided protrudes outward from the end 22e of the second dielectric layer 22 in a plan view.

[0030] The first antenna 3 is disposed on the first main surface S1 of the first dielectric layer 21 to transmit and receive signals in the millimeter wave frequency band. Figure 1As shown, the first antenna 3 is an array antenna in which a plurality of radiating elements 31 are arranged in rows and columns. The plurality of radiating elements 31 are arranged in a manner having a configuration interval P1 in the row direction and a configuration interval P2 in the column direction. Here, the configuration intervals P1 and P2 are intervals between the centroids 31c of adjacent radiating elements 31. The radiating element 31 has a side 31s1 and a side 31s2 facing each other, and a side 31s3 and a side 31s4 between the side 31s1 and the side 31s2. The centroid 31c coincides with the intersection of a virtual line connecting the midpoint of the side 31s1 and the midpoint of the side 31s2 and a virtual line connecting the midpoint of the side 31s3 and the midpoint of the side 31s4. The configuration intervals P1 and P2 are approximately 1 / 2 of the wavelength λ of the signal transmitted and received by the radiating element 31.

[0031] like Figure 3 As shown, the second antenna 4 is provided on the second main surface S2 of the second dielectric layer 22, and transmits and receives signals in the microwave frequency band. The second antenna 4 is a patch antenna composed of a single radiating element. However, the second antenna 4 is not limited to a patch antenna, and may also be a monopole antenna or an inverted F antenna. In addition, a matching component for obtaining matching of the second antenna 4 may also be installed on the first dielectric layer 21.

[0032] The arrangement intervals P1 and P2 of the plurality of radiating elements 31 of the first antenna 3 are 1 / 2 of the wavelength λ of the signal frequency, and therefore, the overall area of ​​the first antenna 3 for transmitting and receiving a signal in the millimeter wave frequency band is determined by the number and arrangement of the radiating elements 31. On the other hand, in the second antenna 4 for transmitting and receiving a signal in the microwave frequency band, it is not an array antenna. The second antenna 4 is provided in the second dielectric layer 22 having a dielectric constant higher than that of the first dielectric layer 21. Therefore, the second antenna 4 can reduce the area by the wavelength shortening effect compared with the case where the second antenna 4 is provided in the first dielectric layer 21.

[0033] In addition, a ground layer 26 is provided in the inner layer of the first dielectric layer 21. The second antenna 4 is a patch antenna composed of a single radiating element, and is arranged to face the ground layer 26. The ground layer 26 is provided between the first antenna 3 and the second antenna 4 facing each other. The antenna module 1 can share a single ground layer 26 with the first antenna 3 and the second antenna 4.

[0034] The ground layer 26 is provided on the first dielectric layer 21, and the interval between the second antenna 4 and the ground layer 26 becomes larger. Compared with the case where the ground layer 26 is provided at the boundary between the first dielectric layer 21 and the second dielectric layer 22, or the case where the ground layer 26 is provided on the second dielectric layer 22, the signal is broadbanded, and the characteristics of the second antenna 4 that transmits and receives signals in the microwave frequency band are improved. In addition, the ground layer 26 can suppress interference between the signal in the millimeter wave frequency band transmitted and received by the first antenna 3 and the signal in the microwave frequency band transmitted and received by the second antenna 4.

[0035] In addition, the antenna module 1 is not limited to a structure in which the first antenna 3 is exposed on the first main surface S1 of the first dielectric layer 21 and the second antenna 4 is exposed on the second main surface S2 of the second dielectric layer 22. For example, the first antenna 3 and the second antenna 4 may be provided in the inner layers of the first dielectric layer 21 and the second dielectric layer 22, respectively, or protective layers may be provided to cover the first antenna 3 and the second antenna 4, respectively. In addition, the shape, number, and arrangement of the plurality of radiating elements 31 are not limited to Figure 1 The structure shown can be modified appropriately.

[0036] The high-frequency circuit 5, the first connector 61, and the second connector 62 are provided on the third main surface S3 of the first dielectric layer 21. The high-frequency circuit 5 is provided so as to be exposed on the third main surface S3 of the first dielectric layer 21. The high-frequency circuit 5 is mounted on the plurality of terminals 211 via a plurality of bumps 51, for example, by flip-chip mounting. The high-frequency circuit 5 is an RFIC (Radio Frequency Integrated Circuit) including a switch for switching transmission and reception, a power amplifier, a low-noise amplifier, a phase shifter, a splitter, a coupler, a mixer, and the like.

[0037] like Figure 3 As shown in FIG. 1 , the high-frequency circuit 5 and the second dielectric layer 22 are provided on the same third main surface S3 of the first dielectric layer 21. The high-frequency circuit 5 is arranged adjacent to the end 22e of the second dielectric layer 22. A ground layer 26 is provided between the high-frequency circuit 5 and the first antenna 3 (radiating element 31) in a direction perpendicular to the first main surface S1. Figure 2 As shown in FIG. 1 , the first connector 61 and the second connector 62 are provided on the outer peripheral side of the first dielectric layer 21 in a plan view. That is, the high frequency circuit 5 is arranged between the first connector 61 and the second connector 62 and the end 22e of the second dielectric layer 22. Figure 1 As shown, at least a part of the plurality of radiating elements 31 is provided in a region overlapping with the high-frequency circuit 5 and the second antenna 4 in a plan view.

[0038] like Figure 3 As shown, the high-frequency circuit 5 is electrically connected to the first antenna 3 and the first connector 61. Specifically, a plurality of first signal paths 23 and connection paths 25 are provided on the first dielectric layer 21. One end of the first signal path 23 is connected to the radiating element 31 on the first main surface S1, and the other end of the first signal path 23 is connected to the high-frequency circuit 5 on the third main surface S3. An opening (not shown) is provided in the ground layer 26 at a portion through which the first signal path 23 passes, and the first signal path 23 is electrically isolated from the ground layer 26. In addition, one end of the connection path 25 is connected to the first connector 61 on the third main surface S3, and the other end of the connection path 25 is connected to the high-frequency circuit 5 on the third main surface S3.

[0039] The second antenna 4 is electrically connected to the second connector 62. Specifically, a second signal path 24 is provided across the first dielectric layer 21 and the second dielectric layer 22. One end of the second signal path 24 is connected to the second antenna 4 on the second main surface S2, and the other end of the second signal path 24 is connected to the second connector 62 on the third main surface S3. The first connector 61 and the second connector 62 are, for example, coaxial connectors that can be connected to a coaxial cable. Alternatively, the first connector 61 and the second connector 62 may also be multi-pole connectors or connectors formed by a flexible substrate. Alternatively, at least one of the first connector 61 and the second connector 62 may be provided on the first main surface S1. In this case, the degree of freedom of installation of the antenna module 1 becomes higher.

[0040] The first signal path 23 and the connection path 25 include: a plurality of vias connecting the layers of the first dielectric layer 21, and wiring provided in the inner layer or the surface layer of the first dielectric layer 21. The second signal path 24 includes: a plurality of vias connecting the layers of the first dielectric layer 21, a plurality of vias connecting the layers of the second dielectric layer 22, and wiring provided in the first dielectric layer 21 and the second dielectric layer 22. At least a portion of the connection path 25 and the second signal path 24 may also be provided in the inner layer of the first dielectric layer 21, or may also be provided on the third main surface S3 of the first dielectric layer 21.

[0041] The first connector 61 is connected to a baseband IC and an IF transceiver IC for transmitting and receiving signals in the millimeter wave frequency band via a cable, and the second connector 62 is connected to an RFIC (Radio Frequency Integrated Circuit) for transmitting and receiving signals in the microwave frequency band via a cable.

[0042] When transmitting a signal in the millimeter wave frequency band, the high frequency circuit 5 uses a mixer to up-convert the IF or IQ signal or the millimeter wave signal as needed, and then amplifies the high frequency signal in the millimeter wave frequency band through the power amplifier in the high frequency circuit 5 and supplies it to the first antenna 3. Alternatively, the high frequency circuit 5 amplifies the high frequency signal in the millimeter wave frequency band through the power amplifier in the high frequency circuit 5 and supplies it to the first antenna 3. By supplying a high frequency signal, a current flows through the radiating element 31 in a specified direction, and a polarized wave parallel to the direction in which the current flows is radiated. Thus, the first antenna 3 transmits a signal in the millimeter wave frequency band. The antenna module 1 obtains a desired radiation pattern (directivity) by controlling the configuration of the radiating element 31, the amplitude and phase of the excited high frequency signal. In addition, when receiving a signal in the millimeter wave frequency band, the high frequency circuit 5 amplifies the high frequency signal received by the first antenna 3 through a low noise amplifier, down-converts it if necessary, and supplies it to the baseband IC and the IF transceiver IC.

[0043] When a signal in the microwave frequency band is transmitted, the RFIC of the external circuit supplies the high-frequency signal in the microwave frequency band to the second antenna 4 via the second connector 62 and the second signal path 24. Thus, the second antenna 4 transmits the signal in the microwave frequency band. In addition, the signal received by the second antenna 4 is supplied to the RFIC of the external circuit via the second signal path 24 and the second connector 62.

[0044] As described above, the antenna module 1 of this embodiment includes a substrate 2, a first antenna 3, a second antenna 4, and a high-frequency circuit 5. The substrate 2 includes: a first dielectric layer 21, and a second dielectric layer 22 having a dielectric constant different from that of the first dielectric layer 21. The first antenna 3 is arranged on the first dielectric layer 21, and transmits and receives signals in the millimeter wave frequency band (first frequency band). The second antenna 4 is arranged on the second dielectric layer 22, and transmits and receives signals in a frequency band lower than the millimeter wave frequency band, that is, a microwave frequency band (second frequency band). The high-frequency circuit 5 is arranged on the substrate 2 and is electrically connected to the first antenna 3.

[0045] In the antenna module 1 of the present embodiment, the dielectric constant of the second dielectric layer 22 is higher than the dielectric constant of the first dielectric layer 21 .

[0046] Thus, the antenna module 1 can transmit and receive signals of multiple different frequencies in the millimeter wave band and the microwave band. In addition, compared with the case where the first antenna 3 is provided in the second dielectric layer 22, the increase in the attenuation of the signal transmitted between the high-frequency circuit 5 and the first antenna 3 can be suppressed. Therefore, the antenna module 1 can transmit and receive signals of multiple different frequencies in the millimeter wave band and the microwave band, and the increase in the attenuation of the signal in the millimeter wave band transmitted between the high-frequency circuit 5 and the first antenna 3 can be suppressed.

[0047] In the antenna module 1 of the present embodiment, in plan view, the area of ​​the first dielectric layer 21 is larger than the area of ​​the second dielectric layer 22. The high-frequency circuit 5 is provided on the third main surface S3 of the first dielectric layer 21 exposed from the second dielectric layer 22.

[0048] Thus, the antenna module 1 can suppress the increase in module size and can provide the first antenna 3, the second antenna 4 and the high-frequency circuit 5 on the substrate 2. That is, the antenna module 1 can be realized that can transmit and receive signals of multiple different frequencies in the millimeter wave band and the microwave band.

[0049] In the antenna module 1 of the present embodiment, the high frequency circuit 5 is provided in the first dielectric layer 21 . The first signal path 23 connecting the first antenna 3 and the high frequency circuit 5 is provided in the first dielectric layer 21 without passing through the second dielectric layer 22 .

[0050] Therefore, compared with the case where the high-frequency circuit 5 is provided in the second dielectric layer 22 , it is possible to suppress an increase in the attenuation of a signal in the millimeter wave frequency band transmitted between the high-frequency circuit 5 and the first antenna 3 .

[0051] Furthermore, in the antenna module 1 of the present embodiment, the second connector 62 electrically connected to the second antenna 4 is provided on the first dielectric layer 21 .

[0052] Thus, the RFIC of the external circuit can supply a high-frequency signal in the microwave frequency band to the second antenna 4 via the second connector 62 and the second signal path 24 .

[0053] (First Modification)

[0054] Figure 4 1 is a cross-sectional view of an antenna module according to a first modification. In the first modification, unlike the above-described embodiment, a structure in which a resin 52 and a shielding layer 53 are provided is described. Figure 4 As shown, in the antenna module 1A, the high frequency circuit 5 is sealed by the resin 52. The resin 52 uses a composite resin containing an inorganic filler in a thermosetting resin. As the thermosetting resin, for example, epoxy resin, phenolic resin, cyanate resin, etc. are used. As the inorganic filler, alumina, silicon dioxide, titanium dioxide, etc. are used. The resin 52 is formed by, for example, a resin molding technology such as a casting technology, a transfer technology, and a compression molding technology.

[0055] In addition, the shielding layer 53 is provided on the surface of the resin 52. The shielding layer 53 uses a conductive metal material. The shielding layer 53 is connected to the ground potential provided in the second dielectric layer 22. Thus, the antenna module 1A can protect the high-frequency circuit 5 and suppress the interference between the signal radiated from the second antenna 4 and the high-frequency circuit 5. In addition, a shielding shell structure can be used instead of the shielding layer 53. In this case, the resin 52 can also be omitted. The shielding shell is made of metal.

[0056] (Second Modification)

[0057] Figure 5 2 is a cross-sectional view of an antenna module of a second modification. In the second modification, unlike the above-mentioned embodiment, a structure in which the second antenna 4 is connected to the ground layer 26 is described. Figure 5 As shown, in the antenna module 1B, a ground connection path 27 is provided to connect the second antenna 4 and the ground layer 26. The ground connection path 27 is provided to penetrate the first dielectric layer 21 and the second dielectric layer 22 between the second antenna 4 and the ground layer 26.

[0058] By connecting the second antenna 4 to the ground layer 26, the path of the current flowing through the second antenna 4 when the signal is supplied from the second connector 62 and the second signal path 24 changes compared to the case where the second antenna 4 is electrically isolated from the ground layer 26. As a result, the radiation characteristics of the signal radiated from the second antenna 4 in the direction parallel to the second main surface S2 are improved.

[0059] (Third Modification)

[0060] Figure 6 2 is a cross-sectional view of an antenna module according to a third modification. In the third modification, unlike the above-described embodiment, a structure in which a filter circuit 28 is provided in the second dielectric layer 22 is described. Figure 6 As shown, in the antenna module 1C, the filter circuit 28 includes: opposing electrodes 29a, 29b, and wiring connected to the opposing electrodes 29a, 29b. The opposing electrodes 29a, 29b are opposed to each other with at least one dielectric layer of the second dielectric layer 22 interposed therebetween. The filter circuit 28 is formed by the capacitance component formed by the opposing electrodes 29a, 29b and the inductance component of the wiring connected to the opposing electrodes 29a, 29b. The filter circuit 28 is a high-pass filter (HPF: High-pass filter) that allows at least signals above the frequency of the millimeter wave band to pass. Although not shown in the figure, the wiring connected to the opposing electrodes 29a, 29b functions as an inductor.

[0061] In this modification, the second dielectric layer 22 and the high-frequency circuit 5 are provided adjacent to each other on the same third main surface S3 of the first dielectric layer 21. The first signal path 23 is provided on the first dielectric layer 21 and the second dielectric layer 22, and connects the radiating element 31, the filter circuit 28, and the high-frequency circuit 5. Specifically, the first signal path 23 includes a first partial signal path 23a and a second partial signal path 23b. The first partial signal path 23a is provided across the first dielectric layer 21 and the second dielectric layer 22, one end of the first partial signal path 23a is connected to the radiating element 31, and the other end of the first partial signal path 23a is connected to the counter electrode 29a. The second partial signal path 23b is provided across the first dielectric layer 21 and the second dielectric layer 22, one end of the second partial signal path 23b is connected to the high-frequency circuit 5, and the other end of the second partial signal path 23b is connected to the counter electrode 29b.

[0062] With such a structure, the filter circuit 28 is formed in the second dielectric layer 22 having a larger dielectric constant than in the case where the filter circuit 28 is provided in the first dielectric layer 21, so that the filter circuit 28 can be miniaturized. In addition, the filter circuit 28 can remove the signal of the frequency component lower than the millimeter wave frequency band in the signal transmitted between the high-frequency circuit 5 and the first antenna 3. Thus, the antenna module 1C can suppress the interference between the transmission and reception of the signal using the first antenna 3 and the transmission and reception of the signal using the second antenna 4. In addition, the filter circuit 28 is not limited to a high-pass filter, and can also be a band-pass filter, for example.

[0063] (Fourth Modification)

[0064] Figure 7 4 is a cross-sectional view of an antenna module according to a fourth modification. In the fourth modification, unlike the above-described embodiment, a structure in which the high-frequency circuit 5 is provided on the first main surface S1 of the first dielectric layer 21 will be described. Figure 7 As shown, the high-frequency circuit 5 is mounted in a region of the first main surface S1 where the plurality of radiating elements 31 are not provided. The high-frequency circuit 5 is provided on the opposite side of the first connector 61 and the second connector 62 with respect to the ground layer 26 .

[0065] The first signal path 23 is provided in the first dielectric layer 21. One end of the first signal path 23 is connected to the radiating element 31 on the first principal surface S1, and the other end of the first signal path 23 is connected to the high-frequency circuit 5 on the first principal surface S1. The connection path 25 is provided in the first dielectric layer 21. One end of the connection path 25 is connected to the first connector 61 on the third principal surface S3, and the other end of the connection path 25 is connected to the high-frequency circuit 5 on the first principal surface S1.

[0066] A ground layer 26 is provided between the second antenna 4, the second signal path 24, the second connector 62, and the high-frequency circuit 5. Thus, the antenna module 1D can suppress interference between the signal radiated from the second antenna 4 and the high-frequency circuit 5. That is, the antenna module 1D is less susceptible to interference from microwave noise.

[0067] The above-described embodiments and the structures of the first to fourth variants can be combined. For example, in the antenna modules 1B, 1C, and 1D of the second to fourth variants, as in the first variant, a structure in which the resin 52 and the shielding layer 53 are not provided can be applied. In addition, in the antenna modules 1C and 1D of the third and fourth variants, as in the second variant, a structure in which the second antenna 4 is connected to the ground layer 26 can be applied. In addition, in the antenna module 1D of the fourth variant, as in the third variant, a structure in which the filter circuit 28 is provided in the second dielectric layer 22 can be applied.

[0068] (Fifth Modification)

[0069] Figure 8 FIG. 1 is a bottom view of an antenna module according to a fifth modification. Fig. 9 FIG. 5 is a cross-sectional view of an antenna module of a fifth modification. In the fifth modification, unlike the above-mentioned embodiment, the second antenna 4A is a monopole antenna. Figure 8 and Fig. 9 As shown, the second antenna 4A is linear and extends in a direction perpendicular to the end 22e. A feed point 41 is provided at the end of the second antenna 4A on the high frequency circuit 5 side. The via 24a of the second signal path 24 is provided across the first dielectric layer 21 to the second dielectric layer 22 in a direction perpendicular to the second main surface S2, and is connected to the feed point 41.

[0070] Through such a structure, the antenna module 1E of the fifth variant can transmit and receive signals of multiple different frequencies in the millimeter wave band and the microwave band, similar to the above-mentioned embodiment, and can suppress the increase in the attenuation of the millimeter wave band signal transmitted between the high-frequency circuit 5 and the first antenna 3.

[0071] (Sixth Modification)

[0072] Fig.10 FIG. 1 is a bottom view of an antenna module according to a sixth modification. Fig.11 FIG. 6 is a cross-sectional view of an antenna module according to a sixth modification. In the sixth modification, unlike the above-described embodiment, the second antenna 4B is an inverted F antenna. Fig.10 and Fig.11 As shown, the second antenna 4B is linear and extends in a direction perpendicular to the end 22e. The via hole 24a of the second signal path 24 is connected to the feed point 42 provided at the end of the second antenna 4A, and a short-circuit line 43 is connected to the central part of the second antenna 4A. The short-circuit line 43 is provided in the second dielectric layer 22 in a direction perpendicular to the second main surface S2. The short-circuit line 43 is parallel to the via hole 24a and is formed shorter than the via hole 24a.

[0073] Through such a structure, the antenna module 1F of the sixth variant can transmit and receive signals of multiple different frequencies in the millimeter wave band and the microwave band, similar to the above-mentioned embodiment, and can suppress the increase in the attenuation of the millimeter wave band signal transmitted between the high-frequency circuit 5 and the first antenna 3.

[0074] (communication device)

[0075] Fig.12 is a block diagram showing the structure of a communication device including an antenna module according to an embodiment. Fig.12As shown, the communication device 100 includes an antenna module 1 , a motherboard 101 , a microwave circuit 102 , a CPU (Central Processing Unit) 103 , a memory 104 , and a millimeter wave circuit 105 . The microwave circuit 102 , the CPU 103 , the memory 104 , and the millimeter wave circuit 105 are mounted on the motherboard 101 .

[0076] The microwave circuit 102 includes a FEM (Front End Module), an RF transceiver, a BB / MAC, etc. The microwave circuit 102 is connected to the second connector 62 of the antenna module 1 .

[0077] The millimeter wave circuit 105 includes BB (Base Band) / MAC (Media Access Control), a converter (up converter, down converter), etc. The millimeter wave circuit 105 is connected to the first connector 61 of the antenna module 1 .

[0078] In addition, the above-mentioned embodiments are for easy understanding of the present invention and are not intended to limit the interpretation of the present invention. The present invention can be changed / improved without departing from the gist thereof, and the present invention also includes its equivalents.

[0079] Explanation of the reference numerals: 1, 1A, 1B, 1C, 1D…antenna module; 2…substrate; 3…first antenna; 4…second antenna; 5…high-frequency circuit; 21…first dielectric layer; 22…second dielectric layer; 23…first signal path; 24…second signal path; 25…connection path; 26…ground layer; 27…ground connection path; 28…filter circuit; 29a, 29b…opposing electrodes; 31…radiating element; 51…bump; 52…resin; 53…shielding layer; 61…first connector; 62…second connector; S1…first principal surface; S2…second principal surface; S3…third principal surface.

Claims

1. An antenna module, comprising: a substrate comprising a first dielectric layer and a second dielectric layer, the second dielectric layer having a dielectric constant different from a dielectric constant of the first dielectric layer; A first antenna, which is disposed on the first dielectric layer and transmits and receives signals in a first frequency band; A second antenna, disposed on the second dielectric layer, for transmitting and receiving signals in a second frequency band, which is lower than the first frequency band; as well as a high frequency circuit, which is disposed in the first dielectric layer and is electrically connected to the first antenna, The second dielectric layer and the high-frequency circuit are provided on a surface of the first dielectric layer opposite to a surface on which the first antenna is provided.

2. The antenna module according to claim 1, wherein: The second dielectric layer has a higher dielectric constant than the first dielectric layer.

3. The antenna module according to claim 1 or 2, wherein: In a plan view, an area of ​​the first dielectric layer is larger than an area of ​​the second dielectric layer.

4. The antenna module according to claim 1 or 2, wherein: A connector electrically connected to the second antenna is provided on the first dielectric layer.

5. The antenna module according to claim 1 or 2, wherein: The high-frequency circuit is sealed with resin.

6. The antenna module according to claim 5, wherein: The high-frequency circuit sealed with resin is provided with a shielding layer.

7. An antenna module comprising: a substrate comprising a first dielectric layer and a second dielectric layer, the second dielectric layer having a dielectric constant different from a dielectric constant of the first dielectric layer; A first antenna, which is disposed on the first dielectric layer and transmits and receives signals in a first frequency band; A second antenna, disposed on the second dielectric layer, for transmitting and receiving signals in a second frequency band, which is lower than the first frequency band; a high-frequency circuit disposed on the surface of the first dielectric layer on which the first antenna is disposed and electrically connected to the first antenna; as well as The ground layer is arranged on the inner layer of the first dielectric layer.

8. The antenna module according to claim 7, wherein: In a plan view, an area of ​​the first dielectric layer is larger than an area of ​​the second dielectric layer.

9. An antenna module comprising: a substrate comprising a first dielectric layer and a second dielectric layer, the second dielectric layer having a dielectric constant different from a dielectric constant of the first dielectric layer; A first antenna, which is disposed on the first dielectric layer and transmits and receives signals in a first frequency band; A second antenna, disposed on the second dielectric layer, for transmitting and receiving signals in a second frequency band, which is lower than the first frequency band; as well as a high frequency circuit, which is disposed in the first dielectric layer and is electrically connected to the first antenna, The second dielectric layer is provided with a filter circuit for passing at least the signal of the first frequency band. The second dielectric layer and the high-frequency circuit are disposed adjacent to each other on the same surface of the first dielectric layer. The antenna module includes a signal path provided in the first dielectric layer and the second dielectric layer and connecting the first antenna, the filter circuit, and the high-frequency circuit.

10. The antenna module according to claim 9, wherein: In a plan view, an area of ​​the first dielectric layer is larger than an area of ​​the second dielectric layer.

11. A communication device comprising: The antenna module according to any one of claims 1 to 10; motherboard; A millimeter wave circuit, which is arranged on the motherboard and connected to the antenna module; as well as The microwave circuit is arranged on the motherboard and connected to the antenna module.

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