Antenna module and communication device provided with same

Abstract

An antenna module (100) is provided with: a substrate (131); a ground electrode (GND) disposed so as to face a first main surface and a second main surface of the substrate (131), the first main surface and the second main surface facing each other; a first sub-array (140) that faces the ground electrode (GND) and is disposed closer to the first main surface side than the ground electrode (GND); a power supply circuit (110) disposed closer to the second main surface side than the ground electrode (GND); a power supply line (151) that connects the power supply circuit (110) and the first sub-array (140); an external connection terminal (210); and a signal line (161) that connects the power supply circuit (110) and the external connection terminal (210), the first subarray (140) comprising a plurality of patch antennas (14), the external connection terminal (210) being disposed at a position that does not overlap the first subarray (140) and the power supply circuit (110) in plan view from a first direction, which is a direction normal to the substrate (131), and the external connection terminal (210) being disposed at a position that does not overlap the first subarray (140) and the power supply circuit (110) in plan view from a second direction that is orthogonal to the first direction, the external connection terminal (210) being disposed at a position that does not overlap the first subarray (140) and the power supply circuit (110) in plan view from the second direction. At least a portion of the signal line (161) is disposed between one or more patch antennas among the plurality of patch antennas (14) and the ground electrode (GND), and the signal line (161) is not disposed at a position overlapping the first sub-array (140) in plan view from the first direction.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to an antenna module and a communication apparatus provided with the same, and more particularly, to a technology for suppressing degradation of antenna characteristics. BACKGROUND

[0002] Generally, an antenna module includes a substrate, and a radiating element and various electronic components mounted on the substrate. As representative examples of such electronic components, RFIC (Radio Frequency Integrated Circuit) and BBIC (Base Band Integrated Circuit) and the like can be cited.

[0003] For example, in International Publication No. 2023 / 100621 (Patent Literature 1), an antenna module is disclosed which is provided with a substrate on which a patch antenna is disposed, and a signal line is disposed between an external connection terminal and an RFIC. The patch antenna is connected to the RFIC through a feed line, and the RFIC functions as a feed circuit for the patch antenna. A mother board on which a BBIC is mounted is connected to the external connection terminal. The feed circuit (RFIC) and the BBIC communicate via the signal line.

[0004] PRIOR ART DOCUMENTS

[0005] PATENT LITERATURE

[0006] Patent Literature 1: International Publication No. 2023 / 100621 SUMMARY

[0007] PROBLEMS TO BE SOLVED BY THE INVENTION

[0008] When the signal line connecting the external connection terminal and the feed circuit passes near the patch antenna, the directivity of the antenna is destroyed due to the influence of the magnetic field generated around the signal line. In an antenna module employing a subarray constituted by a plurality of patch antennas, the destruction of the directivity becomes greater. This is because, in the case where the patch antennas whose directivity is destroyed are subarrayed with each other, the directivity as a whole of the subarray is distorted.

[0009] The present disclosure is achieved to solve the above-described problems, and aims to suppress the case where the directivity of a subarray is distorted due to the influence of a signal flowing between an external connection terminal and a feed circuit in an antenna module employing a subarray.

[0010] SOLUTION TO PROBLEM

[0011] The antenna module disclosed herein comprises: a substrate; a ground electrode disposed facing each other on a first main surface and a second main surface of the substrate; a first subarray facing the ground electrode and disposed at a position closer to the first main surface than the ground electrode; a feed circuit disposed at a position closer to the second main surface than the ground electrode; a feed line connecting the feed circuit to the first subarray; an external connection terminal; and a signal line connecting the feed circuit to the external connection terminal. The first subarray is composed of multiple patch antennas. When viewed from the normal direction of the substrate (i.e., a first direction), the external connection terminal is disposed at a position that does not overlap with the first subarray and the feed circuit. When viewed from a second direction orthogonal to the first direction, at least a portion of the signal line is disposed between one or more of the patch antennas and the ground electrode. When viewed from the first direction, the signal line does not overlap with the first subarray.

[0012] The effects of the invention

[0013] According to this disclosure, in an antenna module employing a subarray, it is possible to suppress the directivity distortion of the subarray caused by the influence of signals flowing between the external connection terminals and the feed circuit. Attached Figure Description

[0014] Figure 1 This is a block diagram of a communication device using the antenna module described in Implementation Method 1.

[0015] Figure 2 yes Figure 1 Top view and side perspective view of the antenna module.

[0016] Figure 3 This is a diagram illustrating a variation 1 of the antenna module according to Embodiment 1.

[0017] Figure 4 This is a diagram illustrating a variation 2 of the antenna module involved in Embodiment 1.

[0018] Figure 5 This is a top view of the antenna module involved in Embodiment 2.

[0019] Figure 6 This shows the application to Figure 5 The diagram shows the wiring method of the feed line of the antenna module.

[0020] Figure 7 This is a diagram illustrating a modified example of the antenna module according to Embodiment 2.

[0021] Figure 8 This shows the application to Figure 7 The diagram shows the wiring method of the feed line of the antenna module. Detailed Implementation

[0022] The embodiments of this disclosure will now be described in detail with reference to the accompanying drawings. Furthermore, the same or equivalent parts in the drawings will be labeled with the same reference numerals, and their descriptions will not be repeated.

[0023] [Implementation Method 1]

[0024] (Basic structure of a communication device)

[0025] Figure 1 This is an example of a block diagram of a communication device 10 using the antenna module 100 described in Embodiment 1. The communication device 10 may be, for example, a portable terminal such as a mobile phone, smartphone, or tablet computer, or a personal computer with communication capabilities. An example of the frequency band of the radio waves used by the antenna module 100 described in Embodiment 1 is millimeter-wave radio waves with center frequencies of 28 GHz and 60 GHz, but radio waves in other frequency bands can also be applied to the antenna module described in this 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 and an antenna device 120. The RFIC 110 is an example of a feed circuit.

[0027] The communication device 10 transmits the signal from BBIC 200 to antenna module 100, up-converts it into a high-frequency signal (RF signal) through RFIC 110, and then radiates it from antenna device 120. The communication device 10 sends the high-frequency signal received by antenna device 120 to RFIC 110, where it is down-converted and processed by BBIC 200.

[0028] Antenna device 120 includes a dielectric substrate 131 and a plurality of patch antennas 14. In this embodiment, an antenna that exhibits pre-designed directivity is formed by combining two or more patch antennas 14. Hereinafter, such an antenna will be referred to as a "subarray". Here, a subarray 140 formed by combining two patch antennas 14 is illustrated as a subarray.

[0029] The dielectric substrate 131 is provided with multiple sub-arrays 140. Figure 1 In the example of multiple subarrays 140, four subarrays 140 are shown.

[0030] RFIC 110 is connected to feed lines provided for each subarray 140. The feed lines from RFIC 110 to subarray 140 branch into two midway and connect to two patch antennas 14 of subarray 140.

[0031] The number of sub-arrays 140 provided to the dielectric substrate 131 is not limited to four. One or more sub-arrays 140 can be provided to the dielectric substrate 131. The number of patch antennas 14 included in the sub-array 140 is not limited to two. The sub-array 140 can include two or more patch antennas 14.

[0032] The RFIC 110 has switches 111A to 111D, 113A to 113D, 117, power amplifiers 112AT to 112DT, low-noise amplifiers 112AR to 112DR, attenuators 114A to 114D, phase shifters 115A to 115D, a signal combining / dividing device 116, a mixer 118, and an amplification circuit 119.

[0033] In the case of transmitting a high-frequency signal, the switches 111A to 111D, 113A to 113D are switched to the power amplifiers 112AT to 112DT side, and the switch 117 is connected to a transmission-side amplifier of the amplification circuit 119. In the case of receiving a high-frequency signal, the switches 111A to 111D, 113A to 113D are switched to the low-noise amplifiers 112AR to 112DR side, and the switch 117 is connected to a reception-side amplifier of the amplification circuit 119.

[0034] A signal transmitted from the BBIC 200 to the RFIC 110 is amplified by the amplification circuit 119 and frequency-converted upward by the mixer 118. The high-frequency signal after the frequency conversion, that is, a transmission signal is divided into four by the signal combining / dividing device 116, and supplied to each sub-array 140 through four signal paths. At this time, by individually adjusting the phase shift degrees of the phase shifters 115A to 115D provided to each signal path, it is possible to adjust the directivity of the antenna device 120. In addition, the attenuators 114A to 114D adjust the intensity of the transmission signal.

[0035] A high-frequency signal received by each sub-array 140, that is, a reception signal is combined by the signal combining / dividing device 116 after passing through different four signal paths. The combined reception signal is frequency-converted downward by the mixer 118 and amplified by the amplification circuit 119, and then transmitted to the BBIC 200.

[0036] The RFIC 110 is formed, for example, as an integrated circuit component including the above-described circuit structure. The RFIC 110 can also be formed as an integrated circuit component of a single chip for each device (switch, power amplifier, low-noise amplifier, attenuator, phase shifter) corresponding to each sub-array 140.

[0037] (Structure of Antenna Module)

[0038] Next, the structure of the antenna module 100 according to Embodiment 1 will be described in detail using Figure 2 Next, the structure of the antenna module 100 according to Embodiment 1 will be described in detail usingFigure 2 yes Figure 1 Top view and side perspective view of antenna module 100. Figure 2 The top part shows a top view of the antenna module 100. Figure 2 (A)), the lower part shows a side perspective view ( Figure 2 (B)

[0039] The antenna module 100 includes a dielectric substrate 131 on which a subarray 140 is mounted and a dielectric substrate 132 on which an RFIC 110 is mounted. The dielectric substrates 131 and 132 have a rectangular shape when viewed from the normal direction.

[0040] The dielectric substrate 131 has substrate surfaces S1 and S2 facing each other. A dielectric substrate 132 and a connector 210 are disposed on substrate surface S2 of the dielectric substrate 131. Substrate surface S3 of the dielectric substrate 132 is bonded to substrate surface S2 of the dielectric substrate 131. Therefore, substrate surface S2 of the dielectric substrate 131 and substrate surface S3 of the dielectric substrate 132 face each other. An RFIC 110 is disposed on substrate surface S4 of the dielectric substrate 132. The RFIC 110 is connected to substrate surface S4 of the dielectric substrate 132 via multiple solder bumps 160. The RFIC 110 can also be connected to the dielectric substrate 132 via a multi-pole connector disposed on substrate surface S4.

[0041] In the following description, the normal direction of the dielectric substrate 131 is defined as the Z-axis direction. In addition, in the plane perpendicular to the Z-axis direction, the direction in which the connector 210 and RFIC 110 are arranged is defined as the X-axis, and the direction orthogonal to the X-axis is defined as the Y-axis.

[0042] The patch antenna 14 constituting the subarray 140 is a flat electrode with a rectangular shape. The subarray 140 is disposed on the substrate surface S1 side of the substrate surface S1 and substrate surface S2 of the dielectric substrate 131. The subarray 140 is disposed inside the dielectric substrate 131. The subarray 140 may also be disposed on the dielectric substrate 131 with the substrate surface S1 exposed.

[0043] A ground electrode GND is provided inside the dielectric substrate 131. The ground electrode GND is arranged in the dielectric substrate 131 such that it covers approximately the entire area of ​​the plane including the X-axis and Y-axis within the dielectric substrate 131. The ground electrode GND faces each subarray 140 in the normal direction of the dielectric substrate 131.

[0044] A high-frequency signal is provided to the subarray 140 from the RFIC 110 via the feed line 151. The feed line 151 is an example of a feed line that provides the high-frequency signal output from the feed circuit (RFIC 110) to the subarray. The feed line 151 connected to the RFIC 110 branches into two branch lines 151c at a branch point 1510 within the dielectric substrate 132, and after passing through the ground electrode GND within the dielectric substrate 131, it connects to the feed points (not shown) of the two patch antennas 14, 14 constituting the subarray 140. The feed line 151 includes in-plane wiring portions 151a and 151b parallel to the substrate surfaces S3 and S4 of the dielectric substrate 132. The in-plane wiring portion 151a forms part of the branch line 151c. The in-plane wiring portions 151a and 151b are wired within the dielectric substrate 132 in a manner parallel to the X-axis.

[0045] A mounting substrate 250 is connected to connector 210. A connector 215 is mounted on mounting substrate 250. By connecting connector 215 of mounting substrate 250 to connector 210, mounting substrate 250 is mounted on dielectric substrate 131.

[0046] Connector 210 is electrically connected to RFIC 110 via signal line 161. Mounting substrate 250 communicates with RFIC 110 via signal line 161. Signal line 161 includes an in-plane wiring portion 161a parallel to substrate surfaces S1 and S2 of dielectric substrate 131. The in-plane wiring portion 161a is wired within dielectric substrate 131 in a manner parallel to the X-axis. A wiring extending from connector 210 along the normal direction of dielectric substrate 131 is connected to one end of in-plane wiring portion 161a. The other end of in-plane wiring portion 161a is connected to wiring extending from RFIC 110 along the normal direction of dielectric substrates 131 and 132.

[0047] When viewed from above, the subarray 140 is arranged on the dielectric substrate 131 at an angle parallel to the X-axis, with the two patch antennas 14 included in the subarray 140. When viewed from above, the plurality of subarrays 140 are arranged in a matrix on the dielectric substrate 131.

[0048] (Definition of subarray)

[0049] Here, a "subarray" is defined. Subarray 140 includes a plurality of patch antennas 14. Subarray 140 may also be configured such that each patch antenna 14 is connected to a branch line branching off from a single feed line in the feed circuit (RFIC 110) wiring. Figure 2The diagram illustrates such a structure. In this structure, the feed line branches externally to the RFIC 110. However, it is also possible that the feed line branches internally to the RFIC 110, with branch lines corresponding to each of the multiple patch antennas 14 routed from the RFIC 110. In this case, the feed line branching internally to the RFIC 110 can be connected to a single signal source within the RFIC 110.

[0050] In this way, a signal from a single signal source is provided to the plurality of patch antennas 14 constituting the subarray 140, and the lines used to provide the signal include branch lines branching off from the signal source. The branch points 1510 of the lines used to provide the signal can be located inside or outside the RFIC 110.

[0051] (Regarding signal cable configuration)

[0052] like Figure 2 As shown in (B), when viewing the dielectric substrate 131 from the Y-axis direction, the in-plane wiring portion 161a of the signal line 161 is routed between the ground electrode GND and the plurality of patch antennas 14. Therefore, the space between the ground electrode GND and the plurality of patch antennas 14 within the dielectric substrate 131 is effectively used as the wiring space for the signal line 161. As a result, compared to the case where the wiring space of the in-plane wiring portion 161a is also provided in the dielectric substrate 131, the height of the antenna module 100 can be reduced.

[0053] When at least a portion of the signal line 161 is routed between the ground electrode GND and the plurality of patch antennas 14, the influence of the magnetic field generated around the signal line 161 needs to be considered. This is because when the signal line 161 passes close to the patch antennas 14, the directivity of the antenna is disrupted due to the magnetic field generated around the signal line. In the antenna module 100 employing a subarray 140 composed of multiple patch antennas 14, the disruption of directivity is greater. This is because when the patch antennas 14 with disrupted directivity are subarrayed together, the directivity of the subarray 140 as a whole is distorted.

[0054] If, when viewed from the normal direction of the dielectric substrate 131, the in-plane wiring portion 161a of the signal line 161 is positioned overlapping with the plurality of patch antennas 14 constituting the subarray 140, the distance between the signal line 161 and the patch antennas 14 becomes closer. Alternatively, when, when viewed from the normal direction of the dielectric substrate 131, the in-plane wiring portion 161a of the signal line 161 is positioned between the plurality of patch antennas 14 constituting the subarray 140, the distance between the signal line 161 and the patch antennas 14 also becomes closer.

[0055] Therefore, in this embodiment, measures are taken to prevent the signal line 161 from passing near the patch antenna 14. That is, in this embodiment, when viewed from the normal direction of the dielectric substrate 131, the in-plane wiring portion 161a of the signal line 161 is not positioned to overlap with the plurality of patch antennas 14 constituting the subarray 140. For example... Figure 2 As shown in (A), the in-plane wiring portion 161a of the signal line 161 overlaps with the X1-X1 line. Subarrays 140 are arranged on both sides of the X1-X1 line.

[0056] Furthermore, in this embodiment, the in-plane wiring portion 161a of the signal line 161 is not disposed between the plurality of patch antennas 14 constituting the subarray 140. For example, as Figure 2 As shown in (A), in-plane wiring portions 151a of feed lines 151 are arranged between the plurality of patch antennas 14 constituting subarray 140, and in-plane wiring portions 161a of signal lines 161 do not intersect with in-plane wiring portions 151a of feed lines 151.

[0057] Therefore, in this embodiment, the signal line 161 can be prevented from passing near the patch antenna 14. As a result, the disruption of the directivity of the plurality of patch antennas 14 constituting the subarray 140 can be reduced, thereby suppressing the directivity distortion of the subarray 140.

[0058] Features related to the signal line configuration as described above are implemented through the following structure in this embodiment: The ground electrode GND is arranged facing each other on substrate surfaces S1 and S2 of the dielectric substrate 131. The subarray 140 radiating radio waves faces the ground electrode GND and is positioned closer to substrate surface S1 than the ground electrode GND. The RFIC 110 providing high-frequency signals to the subarray 140 is positioned closer to substrate surface S2 than the ground electrode GND. Feed lines 151 connecting the signal source of the RFIC 110 to the subarray 140 are routed on the dielectric substrates 131 and 132. Signal lines 161 connecting the RFIC 110 to the connector 210 are routed on the dielectric substrates 131 and 132.

[0059] Subarray 140 consists of multiple patch antennas 14. RFIC 110 provides high-frequency signals to each of the multiple patch antennas 14. When viewed from the normal direction of dielectric substrate 131, connector 210 is positioned to not overlap with subarray 140 and RFIC 110.

[0060] When viewed from above in a direction orthogonal to the normal direction of the dielectric substrate 131 (Y-axis direction), an in-plane wiring portion 161a constituting at least a portion of the signal line 161 is disposed between one or more of the patch antennas 14 and the ground electrode GND. Furthermore, in Figure 2(B) shows an example where the in-plane wiring portion 161a is disposed between one patch antenna 14 and the ground electrode GND. However, it is also possible to configure the in-plane wiring portion 161a to extend along the X-axis direction, thereby disposing between two or more patch antennas 14 and the ground electrode GND.

[0061] When viewed from the normal direction of the dielectric substrate 131, the in-plane wiring portion 161a of the signal line 161 does not overlap with the subarray 140. More specifically, when viewed from the normal direction of the dielectric substrate 131, the in-plane wiring portion 161a of the signal line 161 is not positioned at a location overlapping with the plurality of patch antennas 14 constituting the subarray 140, nor between the plurality of patch antennas 14 constituting the subarray 140.

[0062] Furthermore, substrate surface S1 is an example of a first main surface, and substrate surface S2 is an example of a second main surface. RFIC 110 is an example of a power supply circuit, and connector 210 is an example of an external connection terminal.

[0063] (Regarding the relationship between the signals on the signal line and the signals on the feeder line)

[0064] The high-frequency signal flowing in the feed line 151 is a signal within the frequency band supported by the patch antenna 14. This frequency band is, for example, a band with a center frequency of 28 GHz or 60 GHz. The frequency band of the signal flowing in the signal line 161 varies depending on the type of mounting substrate 250 connected to the connector 210.

[0065] The mounting substrate 250 may house, for example, any of the following: a BBIC, a local oscillator circuit, a control circuit, or a power supply circuit. Additionally, besides these circuits, an antenna module may also be mounted on the mounting substrate 250. However, considering the directivity of the subarray 140, it is desirable not to mount an antenna module on the mounting substrate 250. The reasons for this will be explained later.

[0066] The BBIC outputs the BB signal to signal line 161. The local oscillator circuit outputs the local signal to signal line 161. The control circuit and power supply circuit output the control signal to signal line 161.

[0067] The BB signal has a frequency band of approximately 100MHz to 1GHz. The local signal has a frequency band of approximately 28GHz or approximately 500MHz to 10GHz. The control signal has a frequency band of approximately 100MHz.

[0068] To suppress the directional degradation of the subarray 140, it is desirable to select the circuitry mounted on the mounting substrate 250 such that the frequency band of the signal flowing in the signal line 161 is lower than the frequency band of the signal flowing in the feed line 151. From this perspective, it is desirable to avoid mounting antenna modules on the mounting substrate 250 that function in the same frequency band as or higher than the frequency band of the patch antenna 14.

[0069] Assuming that the mounting substrate 250, which houses the antenna module, is connected to the connector 210, a high-frequency signal flows from the mounting substrate 250 to the signal line 161. For example, if the frequency band of the high-frequency signal flowing through the signal line 161 coincides with the frequency band of the patch antenna 14, resonance occurs, deteriorating the isolation between the patch antenna 14 and the radiating element of the antenna module mounted on the mounting substrate 250. As a result, the directivity of the subarray 140 decreases.

[0070] Therefore, in this embodiment, it is preferable to select the type of mounting substrate 250 to be connected to the connector 210 in such a way that the bandwidth of the signal flowing in the signal line 161 is lower than the bandwidth of the signal flowing in the feed line 151. As a result, it is possible to prevent high-frequency signals that would adversely affect the directivity of the subarray 140 from flowing through the signal line 161.

[0071] More specifically, it is desirable that the described BB signal, local signal, and control signal, etc., flow in signal line 161. Therefore, the bandwidth of the signal passing through signal line 161 is lower than the bandwidth supported by patch antenna 14.

[0072] (Regarding the positional relationship between signal line 161 and multiple subarrays 140)

[0073] like Figure 2 As shown in (A), the antenna module 100 includes a plurality of subarrays 140. When viewed from the normal direction of the dielectric substrate 131, the subarrays 140 are arranged on both sides of the signal line 161 (in-plane wiring portion 161a) and the X1-X1 line on the extension line of the signal line 161 (in-plane wiring portion 161a). That is, when viewed from the normal direction of the dielectric substrate 131, the signal line 161 is arranged between the subarrays 140.

[0074] If multiple subarrays 140 are configured only on one side of the two regions sandwiching signal line 161, radio waves will have difficulty propagating on the side where signal line 161 is located, thus degrading the directivity of the array antenna as a whole (the directivity will deviate from the zenith direction of the substrate). In contrast, if subarrays 140 are configured on both sides of the two regions sandwiching signal line 161 as in this embodiment, signal line 161 affects the subarrays 140 on both sides of signal line 161, thus suppressing the degradation of the directivity of the array antenna as a whole (the deviation of the directivity from the zenith direction of the substrate).

[0075] In addition, Figure 2 In (A), the two patch antennas 14 constituting subarray 140 are arranged along the X-axis to form a "1×2" matrix. However, the two patch antennas 14 constituting subarray 140 can also be arranged along the Y-axis to form a "2×1" matrix. Alternatively, subarray 140 can be composed of three or more patch antennas 14. For example, subarray 140 can also be composed of multiple patch antennas 14 forming a "2×2" or "2×4" matrix.

[0076] (Regarding the dielectric loss tangent of dielectric substrates 131 and 132)

[0077] The dielectric substrates 131 and 132 can be made of various substrates. Examples of various substrates include (1) a low-temperature co-fired ceramic (LTCC) multilayer substrate, (2) a multilayer resin substrate formed by stacking multiple resin layers composed of epoxy, polyimide and other resins, (3) a multilayer resin substrate formed by stacking multiple resin layers composed of liquid crystal polymer (LCP) with a lower dielectric constant, (4) a multilayer resin substrate formed by stacking multiple resin layers composed of fluorine resin, (5) a multilayer resin substrate formed by stacking multiple resin layers composed of PET (polyethylene terephthalate) material, and (6) a ceramic multilayer substrate other than LTCC, etc.

[0078] The dielectric substrates 131 and 132 can be made of the same type of substrate or of different types of substrate. However, it is preferable that the dielectric loss tangent of the dielectric substrate 132 is lower than that of the dielectric loss tangent of the dielectric substrate 131. The reason for this is explained below.

[0079] like Figure 2As shown in (B), the dielectric substrate 132 includes a branch point 1510 where the feed line 151 branches. Generally, impedance matching is difficult at the branch points of signal lines, and matching losses are easily generated at the branch points. In order to reduce the matching loss at the branch points, it is effective to reduce the dielectric loss tangent of the dielectric substrate 132 including the branch point. Therefore, it can be said that in order to reduce the matching loss at the branch points, it is desirable to make the dielectric loss tangent of the dielectric substrate 132 lower than the dielectric loss tangent of the dielectric substrate 131.

[0080] As a substrate with a high dielectric loss tangent, a standard FR-4 PCB (FR-4) substrate can be exemplified. As a substrate with a lower dielectric loss tangent than a standard FR-4 PCB (FR-4) substrate, an LTCC multilayer substrate can be exemplified.

[0081] Alternatively, dielectric substrate 131 and dielectric substrate 132 can be constructed from a single substrate. In this case, when viewed from the Y-axis direction, the substrate is divided into two layers at the boundary between dielectric substrate 131 and dielectric substrate 132 (the boundary between substrate surface S2 and substrate surface S3), and the dielectric loss tangent of the substrate layer on the side where the ground electrode GND is located is different from that of the substrate layer on the side where the branch point 1510 of the feed line 151 is located. In order to reduce the matching loss at the branch point 1510, it is desirable that the dielectric loss tangent of the substrate layer on the side where the branch point 1510 of the feed line 151 is located is lower than that of the substrate layer on the side where the ground electrode GND is located.

[0082] The features related to the dielectric loss tangent as described above are achieved through the following structure in this embodiment. Specifically, the feed line 151 includes a branch line 151c branching at a branch point 1510. The branch point 1510 is disposed on the dielectric substrate 132. In other words, the branch point 1510 is located further from the substrate surface than the ground electrode GND. The dielectric loss tangent of the dielectric substrate 132 is lower than the dielectric loss tangent of the dielectric substrate 131 on which the ground electrode GND is disposed. In other words, the dielectric loss tangent of the portion further from the substrate surface S2 than the ground electrode GND is lower than the dielectric loss tangent of the portion further from the substrate surface S1 than the ground electrode GND.

[0083] (Relationship between signal line 161 and branch line 151c)

[0084] like Figure 2 As shown in (A), when viewed from above the dielectric substrate 131, the branch line 151c of the feed line 151 does not overlap with the signal line 161 (in-plane wiring portion 161a).

[0085] Therefore, compared to the case where the branch line 151c of the feed line 151 overlaps with the signal line 161 (in-plane wiring portion 161a), the distance between the feed line 151 and the signal line 161 can be separated. As a result, electromagnetic coupling between the signal flowing in the feed line 151 and the signal flowing in the signal line 161 can be suppressed. Thus, the directivity degradation of the subarray 140 can be suppressed.

[0086] (Relationship between in-plane wiring section 161a and in-plane wiring sections 151a, 151b 1)

[0087] like Figure 2 As shown in (B), the signal line 161 includes an in-plane wiring portion 161a extending along the X-axis direction, and the feed line 151 includes in-plane wiring portions 151a and 151b extending along the X-axis direction. Figure 3 As shown in (A), when viewed from above the dielectric substrate 131, the in-plane wiring portion 161a of the signal line 161 does not overlap with the in-plane wiring portions 151a and 151b of the feed line 151.

[0088] Therefore, compared to the case where the in-plane wiring portion 161a of the signal line 161 overlaps with the in-plane wiring portions 151a and 151b of the feed line 151 when viewed from above the dielectric substrate 131, the distance between the feed line 151 and the signal line 161 can be separated. As a result, electromagnetic coupling between the signal flowing in the feed line 151 and the signal flowing in the signal line 161 can be suppressed.

[0089] In-plane wiring portions 161a and 151a, 151b extend parallel to the X-axis along an XY plane that includes the X and Y axes. In contrast, via wiring portions, such as branch lines 151c, which are wired by penetrating the substrate layers of dielectric substrates 131, 132 using vias, extend perpendicular to the XY plane. Therefore, the electromagnetic coupling force between the signal flowing in in-plane wiring portion 161a and the signal flowing in in-plane wiring portions 151a, 151b is stronger than the electromagnetic coupling force between the signal flowing in in-plane wiring portion 161a and the signal flowing in via wiring portions (e.g., branch lines 151c).

[0090] In this embodiment, when viewed from above the dielectric substrate 131, the in-plane wiring portion 161a, which is prone to electromagnetic coupling, does not overlap with the in-plane wiring portions 151a and 151b. Therefore, electromagnetic coupling can be reduced more effectively.

[0091] (Relationship between in-plane wiring section 161a and in-plane wiring sections 151a and 151b 2)

[0092] like Figure 3As shown in (B), when viewed from a direction orthogonal to the normal direction of the dielectric substrate 131 (Y-axis direction), a grounding electrode GND is disposed between the in-plane wiring portion 161a of the signal line 161 and the in-plane wiring portions 151a and 151b of the feed line 151.

[0093] As described above, compared to the signal flowing in the in-plane wiring section 161a and the signal flowing in the through-hole wiring section (e.g., branch line 151c), the signal flowing in the in-plane wiring section 161a is more likely to be electromagnetically coupled to the signal flowing in the in-plane wiring sections 151a and 151b.

[0094] In this embodiment, a grounding electrode GND is provided between the in-plane wiring portion 161a and the in-plane wiring portions 151a and 151b, which are prone to electromagnetic coupling. Therefore, electromagnetic coupling can be reduced more effectively.

[0095] (Variation Example 1)

[0096] Next, a variation 1 related to embodiment 1 will be described. Figure 3 This is a diagram illustrating a variation 1 of the antenna module 100 according to Embodiment 1. The antenna module 100A according to Variation 1 includes an RFIC 110 and an antenna device 120A.

[0097] In the antenna module 100A involved in Modification 1, such as Figure 2 As shown, the two patch antennas 14 constituting the subarray 140 are arranged along the Y-axis. Here, to distinguish between the two patch antennas 14 constituting the subarray 140, one patch antenna 14 is referred to as "patch antenna 14a" and the other patch antenna 14 is referred to as "patch antenna 14b". In addition, except that the patch antennas 14a and 14b are arranged along the Y-axis, the antenna module 100A has the same structure as the antenna module 100.

[0098] like Figure 2 As shown, when viewed from above the dielectric substrate 131, the distance d1 between the patch antenna 14a and the signal line 161 (in-plane wiring portion 161a) is greater than the distance d2 between the patch antenna 14b and the signal line 161 (in-plane wiring portion 161a). Therefore, the impact of the signal flowing in the signal line 161 on the performance of the patch antenna 14a can be made less than the impact of the signal flowing in the signal line 161 on the performance of the patch antenna 14b.

[0099] like Figure 4As shown in (A), when the two patch antennas 14 constituting the subarray 140 are arranged along the X-axis, the distance between one of the two patch antennas 14 and the signal line 161 (in-plane wiring portion 161a) is the same as the distance between the other of the two patch antennas 14 and the signal line 161. Therefore, in Figure 4 In the case of the antenna module 100 shown in (A), the signal flowing in the signal line 161 has the same effect on the performance of the two patch antennas 14.

[0100] In contrast, by arranging the two patch antennas 14 (14a, 14b) constituting the subarray 140 along the Y-axis as in Modification 1, the influence of the signal flowing in the signal line 161 on the performance of the patch antenna 14a located away from the signal line 161 can be reduced. In other words, according to Modification 1, the patch antenna 14 that is strongly affected by the signal line 161 can be suppressed to only one of the two patch antennas 14. Therefore, it is possible to prevent the overall directivity of the subarray 140 from being significantly compromised.

[0101] Furthermore, in the antenna module 100A according to Modification 1, the subarray 140 may also be composed of three or more patch antennas 14. In this case, it is desirable to arrange the plurality of patch antennas 14 constituting the subarray 140 along the Y-axis direction. In summary, it is desirable that, when viewed from above the dielectric substrate 131, the distance between the first patch antenna constituting the subarray 140 and the signal line 161 is different from the distance between the second patch antenna constituting the subarray 140 and the signal line 161.

[0102] (Variation Example 2)

[0103] Next, a variation 2 related to embodiment 1 will be described. Figure 2 This is a diagram illustrating a variation 2 of the antenna module 100 according to Embodiment 1. The antenna module 100B according to Variation 2 includes an RFIC 110 and an antenna device 120B.

[0104] In the antenna module 100B involved in Modification Example 2, such as Figure 5 As shown in (B), there is an in-plane wiring portion 161a with signal lines 161 wired between the ground electrode GND and the substrate surface S2.

[0105] In the described antenna module 100, such as Figure 5As shown in (B), a signal line 161 exists between the ground electrode GND and the substrate surface S1. In contrast, in the antenna module 100B according to Modified Example 2, there is no signal line 161 between the ground electrode GND and the substrate surface S1. Therefore, compared with antenna module 100, the antenna module 100B according to Modified Example 2 can reduce the impact of the signal flowing in the signal line 161 on the subarray 140.

[0106] In addition, except that there is no signal line 161 between the ground electrode GND and the substrate surface S1, the antenna module 100B has the same structure as the antenna module 100.

[0107] In antenna module 100B, similarly to antenna module 100, when viewed from above the dielectric substrate 131, the in-plane wiring portion 161a of signal line 161 does not overlap with the in-plane wiring portions 151a and 151b of feed line 151.

[0108] As already explained, the electromagnetic coupling force between the signal flowing in the in-plane wiring section 161a and the signal flowing in the in-plane wiring sections 151a and 151b is stronger than the electromagnetic coupling force between the signal flowing in the in-plane wiring section 161a and the signal flowing in the through-hole wiring section (e.g., branch line 151c).

[0109] In the antenna module 100B involved in Modification Example 2, since the ground electrode GND is not located between the in-plane wiring portions 161a and 151a, 151b, the electromagnetic coupling problem becomes larger compared to the antenna module 100.

[0110] However, when viewed from above the dielectric substrate 131, the in-plane wiring portion 161a, which is prone to electromagnetic coupling, does not overlap with the in-plane wiring portions 151a and 151b. Therefore, in Modification 2, electromagnetic coupling can be reduced more effectively.

[0111] [Implementation Method 2]

[0112] Figure 5 This is a top view of the antenna module 100C according to Embodiment 2. In particular, Figure 6 (A) is the front view. Figure 5 (B) is the rear view. Figure 6 This shows the application to Figure 5 The diagram shows the wiring configuration of the feed line 151 of the antenna module 100C. The antenna module 100C according to Embodiment 2 includes an RFIC 110 and an antenna device 120C.

[0113] The antenna module 100C according to Embodiment 2, like the antenna module 100 according to Embodiment 1, includes dielectric substrates 131 and 132 and connector 210. The antenna module 100C, like the antenna module 100, includes a plurality of subarrays 140 disposed on the dielectric substrate 131 and an RFIC 110 mounted on the dielectric substrate 132.

[0114] However, the antenna module 100C has eight RFICs 110. For example... Figure 2 As shown, each RFIC 110 feeds power to four subarrays 140. Each RFIC 110 is connected to four feed lines 151, which branch off and extend to two patch antennas 14 that constitute the subarray 140. Viewed from above on the dielectric substrate 131, each RFIC 110 is positioned within the four subarrays 140 that it feeds.

[0115] Each RFIC 110 is connected to connector 210 via signal line 161. Figure 5 In, with Figure 5 Similarly, (A) shows the in-plane wiring portion 161a in the signal line 161.

[0116] Antenna module 100C differs from antenna module 100, which lacks both, in having a PMU (Power Management Integrated Unit) 195 and control circuitry 196. The PMU 195 is an example of a power supply circuit. The control circuitry 196 can also be a circuit used to control active components such as switches and amplifiers included in the RFIC 110. The control circuitry 196 may include, for example, a control IC composed of digital circuitry.

[0117] The control circuit 196 is disposed on the front side of the dielectric substrate 131, and the PMU 195 is disposed on the back side of the dielectric substrate 131. The PMU 195 and the control circuit 196 are examples of electronic components.

[0118] Except for the differences described above, antenna module 100C has the same structure as antenna module 100.

[0119] (Beamforming)

[0120] like Figure 6 As shown, each subarray 140 contains electronic components such as a control circuit 196 in the X-axis direction. On the other hand, no electronic components are present in the Y-axis direction of each subarray 140. Therefore, the deflection angle of the beam in the X-axis direction where electronic components are present is smaller than the deflection angle of the beam in the Y-axis direction where electronic components are absent.

[0121] exist Figure 6The diagram shows angles related to beamforming of subarray 140. The beamforming angle in the X-axis direction is, for example, 20 degrees, and the beamforming angle in the Y-axis direction is, for example, 60 degrees.

[0122] When the antenna module 100C is mounted on the side of a structure such as a utility pole perpendicular to the ground, it is desirable that the X-axis direction of the antenna module 100C is aligned with the vertical direction of the structure. This allows the beam deflection angle in the horizontal direction of the structure to be greater than the beam deflection angle in the vertical direction.

[0123] (Relationship between subarray 140 and RFIC 110)

[0124] like Figure 7 As shown, when viewed from above the dielectric substrate 131, the RFIC 110 is positioned surrounded by four subarrays 140 that are the objects to be fed. Here, the two subarrays 140 arranged along the Y-axis of the four subarrays 140 constituting the subarrays 140 are referred to as "subarray 140a" and "subarray 140b", respectively.

[0125] like Figure 7 As shown, the area configured with subarray 140 includes regions 1311a and 1311b separated by signal line 161.

[0126] When viewed from above the dielectric substrate 131, subarray 140a is disposed in region 1311a, which is separated from region 1311b by signal line 161, and subarray 140b is disposed in region 1311b. When viewed from above the dielectric substrate 131, feed line 151 includes a first feed line passing through region 1311a and connected to subarray 140a, and a second feed line passing through region 1311b and connected to subarray 140b.

[0127] (Variation example)

[0128] Figure 7 This is a diagram illustrating a modified example of the antenna module 100C according to Embodiment 2. In particular, Figure 8 (A) is the front view. Figure 7 (B) is the rear view. ​ This shows the application to ​ The diagram shows the wiring configuration of the feed line 151 of the antenna module 100D. In a modified example, the antenna module 100D includes an RFIC 110 and an antenna device 120D.

[0129] Compared to antenna module 100C, the positions of the four subarrays 140 that serve as the feed targets of RFIC 110 differ in antenna module 100D. In antenna module 100D, when viewed from above the dielectric substrate 131, the four subarrays 140 that serve as the feed targets are located in region 1311a of the two regions 1311a and 1311b separated by signal lines 161.

[0130] When viewed from above the dielectric substrate 131, subarray 140a is disposed in region 1311a, which is separated from region 1311b by signal line 161. Subarray 140b is also disposed in region 1311a. When viewed from above the dielectric substrate 131, feed line 151 includes a first feed line that passes through region 1311a and is connected to subarray 140a, and a second feed line that passes through region 1311a and is connected to subarray 140b.

[0131] (Comparison of Antenna Module 100C and Antenna Module 100D)

[0132] Comparing antenna module 100C and antenna module 100D, antenna module 100C has a shorter wiring length from RFIC 110 to subarray 140 compared to antenna module 100D. Therefore, antenna module 100C can reduce transmission loss compared to antenna module 100D. As a result, antenna gain can be improved.

[0133] Comparing antenna module 100C and antenna module 100D, antenna module 100C has one RFIC 110 in each of eight locations, while antenna module 100D has two RFIC 110s in each of four locations. The difference lies in the placement of two RFIC 110s in each of the four locations, compared to one RFIC 110 in each of the eight locations. This reduces the number of subarrays affected by the signal line 161, thus suppressing the degradation of the directivity of the array antenna as a whole (directivity deviation from the substrate zenith direction).

[0134] [Way]

[0135] Those skilled in the art will understand that the above embodiments are specific examples of the following methods.

[0136] (First aspect) An antenna module according to one method comprises: a substrate; a ground electrode disposed facing each other on a first main surface and a second main surface of the substrate; a first subarray facing the ground electrode and disposed at a position closer to the first main surface than the ground electrode; a feed circuit disposed at a position closer to the second main surface than the ground electrode; a feed line connecting the feed circuit to the first subarray; an external connection terminal; and a signal line connecting the feed circuit to the external connection terminal, wherein the first subarray is composed of a plurality of patch antennas, and when viewed from the normal direction of the substrate, i.e., a first direction, the external connection terminal is disposed at a position that does not overlap with the first subarray and the feed circuit, and when viewed from a second direction orthogonal to the first direction, at least a portion of the signal line is disposed between one or more of the patch antennas and the ground electrode, and when viewed from the first direction, the signal line does not overlap with the first subarray.

[0137] (Second item) In the antenna module of the first item, the multiple patch antennas include a first patch antenna and a second patch antenna. When viewed from the first direction, the distance between the first patch antenna and the signal line is different from the distance between the second patch antenna and the signal line.

[0138] (Third item) In the antenna module of the first or second item, the frequency band of the signal flowing in the signal line is lower than the frequency band supported by the multiple patch antennas.

[0139] (Fourth item) The antenna module described in any one of the first to third items further includes a second subarray, wherein, when viewed from the first direction, the signal line is arranged between the first subarray and the second subarray.

[0140] (Fifth item) In any one of the first to fourth items of the antenna module, the feed line includes a branch line branching off at a branch point located on the second main surface side of the substrate, where the branch point is located on the second main surface side of the substrate, and the dielectric loss tangent of the portion of the substrate on the second main surface side of the substrate is lower than the dielectric loss tangent of the portion on the first main surface side of the substrate.

[0141] (Sixth item) In any of the first to fourth items of the antenna module, the feed line includes a branch line branching off at the branch point, which does not overlap with the signal line when viewed from the first direction.

[0142] (Seventh item) In the antenna module described in any one of the first to sixth items, the signal line and the feed line each include an in-plane wiring portion arranged extending along the second direction, wherein when viewed from the second direction, the in-plane wiring portion of the signal line and the in-plane wiring portion of the feed line do not overlap.

[0143] (Eighth item) In the antenna module described in any one of items 1 to 6, the signal line and the feed line each include an in-plane wiring portion extending along a second direction. When viewed from the second direction, the in-plane wiring portions of the signal line and the feed line are both disposed in the portion of the substrate that is closer to the first main surface than the ground electrode, or both are disposed in the portion that is closer to the second main surface than the ground electrode. When viewed from the first direction, the in-plane wiring portions of the signal line and the feed line do not overlap.

[0144] (Ninth item) In the antenna module described in any one of items one through six, the signal line and the feed line each include an in-plane wiring portion extending along the second direction, and when viewed from the second direction, the ground electrode is disposed between the in-plane wiring portion of the signal line and the in-plane wiring portion of the feed line.

[0145] (Item 10) In the antenna module of the first item, a second subarray is further provided, wherein when viewed from the first direction, the first subarray is disposed in a first region of a first region and a second region separated by the signal line, and the second subarray is disposed in the second region. When viewed from the first direction, the feed line includes a first feed line passing through the first region and connected to the first subarray, and a second feed line passing through the second region and connected to the second subarray.

[0146] (Item 11) In the antenna module of the first item, a second subarray is further provided, wherein when viewed from the first direction, the first subarray and the second subarray are configured in a first region of a first region and a second region separated by the signal line, and the feed line includes a first feed line passing through the first region and connected to the first subarray, and a second feed line passing through the first region and connected to the second subarray.

[0147] (Item 12) The communication device involved in other methods is equipped with an antenna module according to any one of items 1 to 11.

[0148] It should be considered that the embodiments disclosed herein are illustrative and not restrictive in all respects. The scope of the invention is defined not by the description of the above embodiments, but by the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims.

[0149] Explanation of reference numerals in the attached figures

[0150] 10: Communication device; 14, 14a, 14b: Patch antenna; 100, 100A~100D: Antenna module; 110: RFIC; 111A~111D, 113A~113D, 117: Switch; 112AR~112DR: Low noise amplifier; 112AT~112DT: Power amplifier; 114A~114D: Attenuator; 115A~115D: Phase shifter; 116: Signal synthesizer / demultiplexer; 118: Mixer; 119: Amplifier circuit; 120, 120A~120D: Antenna device; 131 132: Dielectric substrate; 140, 140a, 140b: Subarray; 151: Feed line; 151a, 151b, 161a: In-plane wiring section; 151c: Branch line; 160: Solder bump; 161: Signal line; 170: PMIC; 195: PMU (Power Module); 196: Control circuit; 200: BBIC; 210, 215: Connector; 250: Mounting substrate; 1311a, 1311b: Area; 1510: Branch point; GND: Ground electrode; S1, S2, S3, S4: Substrate surface.

Claims

1. An antenna module, comprising: substrate; A grounding electrode is disposed facing each other on the first and second main surfaces of the substrate; The first subarray faces the ground electrode and is positioned closer to the first main surface than the ground electrode. A power supply circuit is positioned closer to the second main surface than the ground electrode; A feeder line that connects the feeder circuit to the first sub-array; External connection terminals; as well as The signal line connects the power supply circuit to the external connection terminal. The first subarray consists of multiple patch antennas. When viewed from the normal direction of the substrate, i.e., the first direction, the external connection terminal is positioned so as not to overlap with the first sub-array and the power supply circuit. When viewed from a second direction orthogonal to the first direction, at least a portion of the signal line is disposed between one or more of the plurality of patch antennas and the ground electrode. When viewed from the first direction, the signal line does not overlap with the first subarray.

2. The antenna module according to claim 1, wherein, The plurality of patch antennas includes a first patch antenna and a second patch antenna. When viewed from the first direction, the distance between the first patch antenna and the signal line is different from the distance between the second patch antenna and the signal line.

3. The antenna module according to claim 1 or 2, wherein, The frequency band of the signal flowing in the signal line is lower than the frequency band supported by the plurality of patch antennas.

4. The antenna module according to any one of claims 1 to 3, wherein, It also has a second subarray. When viewed from the first direction, the signal line is positioned between the first subarray and the second subarray.

5. The antenna module according to any one of claims 1 to 4, wherein, The feeder line includes branch lines that branch off at the branch point. The branch point is located closer to the second main surface than the grounding electrode. The dielectric loss tangent of the portion of the substrate that is closer to the second main surface than the ground electrode is lower than the dielectric loss tangent of the portion that is closer to the first main surface than the ground electrode.

6. The antenna module according to any one of claims 1 to 4, wherein, The feeder line includes branch lines that branch off at the branch point. When viewed from the first direction, the branch line does not overlap with the signal line.

7. The antenna module according to any one of claims 1 to 6, wherein, The signal line and the feed line each include an in-plane wiring portion extending along the second direction. When viewed from the second direction, the in-plane wiring portion of the signal line does not overlap with the in-plane wiring portion of the feed line.

8. The antenna module according to any one of claims 1 to 6, wherein, The signal line and the feed line each include an in-plane wiring portion extending along the second direction. When viewed from the second direction, both the in-plane wiring portion of the signal line and the in-plane wiring portion of the feed line are disposed in the portion of the substrate that is closer to the first main surface than the ground electrode, or both are disposed in the portion that is closer to the second main surface than the ground electrode. When viewed from the first direction, the in-plane wiring portion of the signal line does not overlap with the in-plane wiring portion of the feed line.

9. The antenna module according to any one of claims 1 to 6, wherein, The signal line and the feed line each include an in-plane wiring portion extending along the second direction. When viewed from the second direction, the grounding electrode is disposed between the in-plane wiring portion of the signal line and the in-plane wiring portion of the feed line.

10. The antenna module according to claim 1, wherein, It also has a second subarray. When viewed from the first direction, the first subarray is configured in the first region of a first region and a second region separated by the signal lines, and the second subarray is configured in the second region. When viewed from the first direction, the feed line includes a first feed line passing through the first region and connected to the first subarray, and a second feed line passing through the second region and connected to the second subarray.

11. The antenna module according to claim 1, wherein, It also has a second subarray. When viewed from the first direction, the first subarray and the second subarray are configured in the first region of the first region and the second region separated by the signal lines. The feed line includes a first feed line that passes through the first region and is connected to the first sub-array, and a second feed line that passes through the first region and is connected to the second sub-array.

12. A communication device comprising an antenna module according to any one of claims 1 to 11.

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