Patent Publication Number: US-2022216585-A1

Title: Antenna module and communication device including the same

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     The present application is a continuation application of International Patent Application No. PCT/JP2020/026834, filed Jul. 09, 2020, which claims priority to Japanese patent application JP 2019-176986, filed Sep. 27, 2019, the entire contents of each of which being incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates to an antenna module including an antenna substrate including an antenna element and a power supply component (radio-frequency integrated circuit or RFIC) mounted on the antenna substrate, and to a communication device including the antenna module. 
     BACKGROUND ART 
     U.S. Patent Application Publication No. 2016/0056544 discloses an antenna module including a planar antenna substrate and a power supply component mounted on a lower surface of the antenna substrate. A first antenna element and a second antenna element are respectively disposed on an upper surface and a lower surface of the antenna substrate. The power supply component is electrically connected to the first antenna element and the second antenna element to supply radio-frequency signals to the first antenna element and the second antenna element. 
     The antenna substrate has an overhang portion extending outward from a portion on which the power supply component is mounted. The second antenna element is partially disposed on the lower surface of the overhang portion. This structure can increase the area for receiving the antenna element compared to an antenna substrate not including an overhang portion. This structure allows even an antenna substrate with a small area for receiving a power supply component to retain appropriate antenna characteristics. 
     CITATION LIST 
     Patent Document 
     Patent Document 1: U.S. Patent Application Publication No. 2016/0056544 
     SUMMARY 
     Technical Problems 
     A typical power supply component includes an active element such as an amplifier circuit. When the power supply component supplies a radio-frequency signal to the antenna element, the active element in the power supply component generates a large amount of heat. The overhang portion of the antenna substrate extends outward from a portion that receives the power supply component, and heat of the power supply component is also transmitted to the overhang portion. The overhang portion of the antenna substrate is thus desirably used to actively dissipate heat of the antenna module. 
     However, as recognized by the present inventors, U.S. Patent Application Publication No.  2016 / 0056544  has no description on heat dissipation using the overhang portion of the antenna substrate, and thus has room for improvement. 
     The present disclosure is made to solve the above problem, as well as other problems, and aims to provide an antenna module including an antenna substrate and a power supply component, and improving heat dissipation characteristics while retaining antenna characteristics even having a small area for receiving the power supply component. 
     Example Solutions 
     The present disclosure provides an antenna module that includes an antenna substrate including a first surface, a second surface opposite to the first surface, and an antenna element, and a power supply component (radio frequency integrated circuit) mounted on the second surface of the antenna substrate and connected to the antenna element. The antenna substrate includes a mount portion on which the power supply component is mounted and an overhang portion that extends outward from the mount portion. At least part of the antenna element is disposed on the first surface in the overhang portion or disposed in a layer between the first surface and the second surface. The antenna module further includes a heat dissipator, that includes a thermally conductive material, disposed on the second surface in the overhang portion. 
     Another antenna module according to the present disclosure includes an antenna substrate including a first surface, a second surface opposite to the first surface, and an antenna element, and a power supply component mounted on the second surface of the antenna substrate and connected to the antenna element. The antenna substrate includes a mount portion on which the power supply component is mounted and an overhang portion that extends outward from the mount portion. At least part of the antenna element is disposed in the overhang portion on the first surface or between the first surface and the second surface. The mount portion of the antenna substrate includes a rigid substrate and a flexible substrate laminated one on top of another. The overhang portion of the antenna substrate is formed from a flexible substrate without a rigid substrate. The antenna module further includes a heat dissipator that is in contact with the overhang portion. 
     The antenna substrate in the antenna module includes, in addition to the mount portion on which the power supply component is mounted, the overhang portion that extends outward from the mount portion. This antenna substrate can have a larger area for receiving the antenna element than an antenna substrate not including the overhang portion. This structure allows even an antenna module with a small area for receiving a power supply component (area of the mount portion) to retain antenna characteristics. A heat dissipator is also disposed on the overhang portion. Thus, heat transmitted from the power supply component to the overhang portion can be actively dissipated to the outside of the antenna module from the heat dissipator. Even having a small area for receiving a power supply component, an antenna module with this structure can improve heat dissipation characteristics while retaining antenna characteristics. 
     Advantageous Effects 
     According to the present disclosure, an antenna module including an antenna substrate and a power supply component can improve heat dissipation characteristics while retaining antenna characteristics even when having a small area for receiving the power supply component. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is an example block diagram of a communication device. 
         FIG. 2  is a perspective view of an inside of a communication device. 
         FIG. 3  is a perspective view of an inside of a communication device according to Modification Example 1. 
         FIG. 4  is a perspective view of an inside of a communication device according to Modification Example 2. 
         FIG. 5  is a perspective view of an inside of a communication device according to Modification Example 3. 
         FIG. 6  is a perspective view of an inside of a communication device according to Modification Example 4. 
         FIG. 7  is a perspective view of an inside of a communication device according to Modification Example 5. 
         FIG. 8  is a perspective view of an inside of a communication device according to Modification Example 7. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Embodiments of the present disclosure will be described in detail below with reference to the drawings. The same or similar components throughout the drawings are denoted with the same reference signs without redundant description. 
     (Basic Structure of Communication Device) 
       FIG. 1  illustrates an example of a block diagram of a communication device  10  including an antenna module  100  according to an embodiment. Examples of the communication device  10  include a mobile terminal such as a mobile phone, smartphone, or tablet computer, and a personal computer including a communication function. 
     With reference to  FIG. 1 , the communication device  10  includes the antenna module  100  and a baseband integrated circuit (BBIC)  200  forming a baseband signal processing circuit. The antenna module  100  includes a radio frequency integrated circuit (RFIC)  110 , serving as an example of a power supply component, and an antenna device  120  (antenna substrate  30 ). The communication device  10  upconverts a signal transmitted from the BBIC  200  to the antenna module  100  into a radio-frequency signal and emits the signal from the antenna device  120 , and downconverts the radio-frequency signal received at the antenna device  120  and processes the signal at the BBIC  200 . 
     The antenna device  120  includes multiple feed elements  121 . For ease of illustration,  FIG. 1  only illustrates a structure for four of the multiple feed elements  121  included in the antenna device  120 , and omits the structure for the remaining feed elements  121  having the similar structure. Although  FIG. 1  illustrates an example where the antenna device  120  includes multiple feed elements  121  arranged in a two-dimensional array, the antenna device  120  does not have to include multiple feed elements  121 , and may include a single feed element  121 . In the present embodiment, each feed element  121  is a patch antenna having a substantially square planar board shape. 
     The RFIC  110  includes switches  111 A to  111 D,  113 A to  113 D, and  117 , power amplifiers  112 AT to  112 DT, low-noise amplifiers  112 AR to  112 DR, attenuators  114 A to  114 D, phase shifters  115 A to  115 D, a signal multiplexer/demultiplexer  116 , a mixer  118 , and an amplifier circuit  119 . 
     To transmit radio-frequency signals, the switches  111 A to  111 D and  113 A to  113 D are switched to the power amplifiers  112 AT to  112 DT, and the switch  117  is connected to a transmission amplifier of the amplifier circuit  119 . To receive radio-frequency signals, the switches  111 A to  111 D and  113 A to  113 D are switched to the low-noise amplifiers  112 AR to  112 DR, and the switch  117  is connected to a reception amplifier of the amplifier circuit  119 . 
     A signal transmitted from the BBIC  200  is amplified by the amplifier circuit  119 , and upconverted by the mixer  118 . The upconverted transmitted signal, which is a radio- frequency signal, is divided into four waves by the signal multiplexer/demultiplexer  116 , and the four waves are fed to the respective feed elements  121  through four signal paths. The phase shifters  115 A to  115 D located on the respective signal paths have the shift degrees individually adjusted to enable adjustment of the directivity of the antenna device  120 . 
     The received signals, which are radio-frequency signals received by the respective feed elements  121 , pass the respective four signal paths, and are multiplexed by the signal multiplexer/demultiplexer  116 . The multiplexed received signal is downconverted by the mixer  118 , amplified by the amplifier circuit  119 , and transmitted to the BBIC  200 . 
     The RFIC  110  is, for example, a single-chip integrated circuit component including the above circuit structure. Alternatively, devices (switches, power amplifiers, low- noise amplifiers, attenuators, or phase shifters) in the RFIC  110  corresponding to the feed elements  121  may each be formed as a single-chip integrated circuit component for the corresponding feed element  121 . 
     (Arrangement of Antenna Module) 
       FIG. 2  is a perspective view of an inside of the communication device  10 . The communication device  10  is covered with a housing  11 . A housing  11  accommodates components such as the antenna module  100 , a mount substrate  20 , a heat dissipator  70 , and a shielding case  80 . The antenna module  100  includes an antenna substrate  30  included in the antenna device  120 , an RF module  60  including the RFIC  110 , and a circuit board  40 . 
     The antenna substrate  30  and the circuit board  40  may each be formed from, for example, low temperature co-fired ceramics (;TCC), a printed circuit board, or a flexible substrate. 
     The antenna substrate  30  includes an upper surface  30   a , a lower surface  30   b  opposite to the upper surface  30   a , a side surface  30   c  connecting the upper surface  30   a  and the lower surface  30   b , multiple planar feed elements  121 , and a planar ground electrode  122 . Hereinbelow, a direction normal to the upper surface  30   a  of the antenna substrate  30  is also referred to as “a Z-axis direction”, a direction normal to the side surface  30   c  of the antenna substrate  30  is also referred to as “an X-axis direction”, and a direction perpendicular to the Z-axis direction and the X- axis direction is also referred to as “a Y-axis direction”. 
       FIG. 2  illustrates an example where two feed elements  121  are arranged side-by-side in the X-axis direction (along the upper surface  30   a ). The two feed elements  121  are disposed in a layer between the upper surface  30   a  and the lower surface  30   b  of the antenna substrate  30 . Each feed element  121  may be disposed on the upper surface  30   a  of the antenna substrate  30 . 
     The ground electrode  122  is disposed in a layer in the antenna substrate  30  between the feed elements  121  and the lower surface  30   b , and extends in the X-axis direction (in a direction along the upper surface  30   a ). The feed elements  121  and the ground electrode  122  form a patch antenna.  
     The upper surface  30   a , the lower surface  30   b , the feed elements  121 , and the ground electrode  122  may respectively correspond to “an antenna substrate”, “a first surface”, “a second surface”, “an antenna element”, and “a ground electrode” in the present disclosure. 
     The RF module  60  is formed by sealing the RFIC  110  in a resin molding member  50 . The RFIC  110  of the RF module  60  is mounted on the lower surface  30   b  of the antenna substrate  30  with the circuit board  40  interposed therebetween. Wires (or more generally conductors) that connect the RFIC  110  to each of the feed elements  121  of the antenna substrate  30  are arranged on the circuit board  40 . In other words, the RFIC  110  is connected to each of the feed elements  121  with the circuit board  40  interposed therebetween, and supplies radio-frequency (RF) signals to each feed element  121 . A combination of the antenna substrate  30  and the circuit board  40  may correspond to “an antenna substrate” in the present disclosure. Alternatively, the RFIC  110  may be directly mounted on the lower surface  30   b  of the antenna substrate  30  without including the circuit board  40 . When the circuit board  40  is eliminated, the antenna substrate  30  may correspond to “an antenna substrate” in the present disclosure. The RFIC  110  may correspond to “a power supply component” in the present disclosure. 
     The mount substrate  20  is located across from the antenna substrate  30  with the RF module  60  interposed therebetween. The RF module  60  is mounted on an upper surface  20   a  of the mount substrate  20 . The mount substrate  20  may correspond to “a mount substrate” in the present disclosure. 
     The shielding case  80  is located adjacent to the RF module  60  and between the heat dissipator  70  and the mount substrate  20 . Thus, the RF module  60  and the shielding case SO are disposed adjacent to each other on the upper surface  20   a  of the mount substrate  20 . 
     The shielding case  80  is formed from a grounded conductor. The upper surface of the shielding case  80  is in contact with the heat dissipator  70 , and the lower surface of the shielding case SO is in contact with the upper surface  20   a  of the mount substrate  20 . The shielding case  80  accommodates electronic components  81  and  82  (such as a power supply circuit and an inductor). The electronic components  81  and  82  accommodated in the shielding case  80  are protected from electromagnetic noise (which electromagnetic interference, EMI, as used in this description) from components external to the shielding case  80  (such as the feed elements  121 ). In addition, the effect of the electromagnetic noise from the electronic components  81  and  82  (such as switching noise caused by the power supply circuit) on components out of the shielding case  80  (such as the feed elements  121 ) is reduced. 
     As described above, the upper surface  20   a  of the mount substrate  20  receives, besides the RF module  60 , the shielding case  80  adjacent to the RF module  60 . Thus, the area of the upper surface  20   a  of the mount substrate  20  for receiving the RF module  60  is restricted by the area for receiving the shielding case  80 , and thus prevented from further size increase. 
     In view of this, the antenna substrate  30  according to the present embodiment includes, besides a mount portion AO on which the RF module  60  is mounted, an overhang portion Al that extends outward (in an X-axis positive direction) from the mount portion A 0 . The two feed elements  121  are respectively disposed in the mount portion A 0  and the overhang portion A 1  of the antenna substrate  30 . The ground electrode  122  extends throughout the antenna substrate  30  including the mount portion A 0  and the overhang portion A 1 . Thus, the area for receiving the feed elements  121  and the ground electrode  122  can be further increased than in the antenna substrate  30  not including the overhang portion A 1 . Thus, even when having a small area for receiving the RF module  60 , the antenna module  100  can retain antenna characteristics. 
     The RFIC  110  in the RF module  60  includes active elements such as the amplifier circuit  119  and the power amplifiers  112 AT to  112 DT. When the RFIC  110  supplies radio-frequency signals to the feed elements  121 , the active elements in the RFIC  110  generate a large amount of heat. 
     Heat generated in the RFIC  110  is also transmitted to the mount portion A 0  and the overhang portion A 1  of the antenna substrate  30 . Thus, heat transmitted from the RFIC  110  to the overhang portion A 1  is preferably actively dissipated to the outside of the antenna module  100 . 
     In view of this, the heat dissipator  70  is disposed on the lower surface  30   b  in the overhang portion A 1  in the antenna substrate  30  according to the present embodiment. The heat dissipator  70  is formed from a highly thermally conductive material such as a copper electrode or a graphite sheet. The term “thermally conductive material” may include a single material or multiple materials, but collectively they are referred to as a thermally conductive material. Thus, heat transmitted from the RFIC  110  to the overhang portion A 1  can be actively dissipated from the heat dissipator  70  to the outside of the antenna module  100 . 
     In the above example illustrated in  FIG. 2 , the heat dissipator  70  is located within the lower surface  30   b  in the overhang portion A 1 . Instead, the heat dissipator  70  may extend to the lower surface  30   b  of the mount portion A 0  from the lower surface  30   b  in the overhang portion A 1 . Alternatively, the heat dissipator  70  may extend to the side surface  30   c  from the lower surface  30   b  in the overhang portion A 1 . Still alternatively, the heat dissipator  70  may be divided into a member disposed on the lower surface  30   b  in the overhang portion A 1  and a member disposed on the side surface  30   c  of the overhang portion A 1 . 
     In the present embodiment, the shielding case  80  is in contact with the heat dissipator  70 , and thus, heat of the overhang portion A 1  can be actively dissipated to the shielding case  80 . Thus, the antenna module  100  can improve heat dissipation characteristics. A structure not including the shielding case  80  can also dissipate heat into the air through the overhang portion A 1 . 
     In the antenna module  100  according to the present embodiment, the shielding case  80  is disposed between the heat dissipator  70  and the mount substrate  20  and in contact with the heat dissipator  70  and the mount substrate  20 . Thus, heat of the overhang portion A 1  can be actively released to the shielding case  80  and the mount substrate  20  from the heat dissipator  70 . Thus, heat of the overhang portion A 1  can be more efficiently dissipated to the outside. 
     The antenna module  100  according to the present embodiment can thus improve heat dissipation characteristics while retaining antenna characteristics. The mount portion A 0 , the overhang portion A 1 , the heat dissipator  70 , and the shielding case  80  may respectively correspond to “a mount portion”, “an overhang portion”, “a heat dissipator” (or “thermally conductive material”), and “a contact member” in the present disclosure. 
     Modification Example 
     Modification Example 1 
       FIG. 3  is a perspective view of an inside of a communication device  10 A according to Modification Example 1. The communication device  10 A includes an antenna substrate  30 A, instead of the antenna substrate  30  in the communication device  10 . The antenna substrate  30 A is formed by adding, to the antenna substrate  30 , an electrically conductive member  71  (also referred to an electrically conductive material) that connects the ground electrode  122  and the heat dissipator  70 . The electrically conductive member  71  is formed from a highly thermally conductive material such as a copper electrode or an electrically conductive paste. The electrically conductive member  71  is, for example, a via, pillar, or post (of any cross-sectional shape). 
     In this modification, heat generated in the RFIC  110  can be efficiently transmitted to the heat dissipator  70  via the ground electrode  122  and the electrically conductive member  71  in the antenna substrate  30 . Thus, the antenna module  100  can further improve heat dissipation characteristics. “The electrically conductive member  71 ” in Modification Example 1 may correspond to “an electrically conductive member” (or electrically conductive material) in the present disclosure. 
     Modification Example 2 
       FIG. 4  is a perspective view of an inside of a communication device  10 B according to Modification Example 2. The communication device  10 B includes an antenna substrate  30 B instead of the antenna substrate  30  in the communication device  10 . The antenna substrate  30 B includes a ground electrode  122 B instead of the ground electrode  122  in the antenna substrate  30 , and additionally includes electrically conductive members  72  and  73 . 
     The electrically conductive member  72  electrically connects a feeder Ps (or a feed line) in the ground electrode  122 B to the RFIC  110 . The electrically conductive member  73  electrically connects a grounded portion Pg in the ground electrode  122 B to the heat dissipator  70 . In other words, the ground electrode  122 B includes the feeder Ps that feeds power from the RFIC  110  through the electrically conductive member  72 , and the grounded portion Pg grounded through the electrically conductive member  73 , the heat dissipator  70 , and the shielding case  80 . Thus, the ground electrode  122 B can function as an inverted-F antenna. More specifically, when the RFIC  110  supplies radio-frequency signals to the feed elements  121 , the ground electrode  122 B functions as a ground electrode of each feed element  121  (patch antenna). On the other hand, when the RFIC  110  supplies radio-frequency signals to the feeder Ps in the ground electrode  122 B, the ground electrode  122 B functions as an inverted-F antenna that radiates electric waves. When the ground electrode  122 B functions as an inverted-F antenna, since the heat dissipator  70  contains an electrically conductive material, the grounded portion Pg in the ground electrode  122 B is grounded through the electrically conductive member  73 , the heat dissipator  70 , and the shielding case  80 . The feeder Ps may be a feeding point (start point of quarter wavelength), or may be anything other than a feeding point (another feeding point may be provided separately from the feeder Ps). 
     Thus, the ground electrode  122 B of the patch antenna may be modified to also function as an inverted-F antenna. Thus, the antenna module  100  can include both a patch antenna and an inverted-F antenna, and can thus improve communication performance. “The grounded portion Pg” and “the feeder Ps” in Modification Example 2 may respectively correspond to “a grounded portion” and “a feeder” in the present disclosure. 
     Modification Example 3 
       FIG. 5  is a perspective view of an inside of a communication device  10 C according to Modification Example 3. The communication device  10 C includes an antenna substrate  30 C instead of the antenna substrate  30 B in the communication device  10 B illustrated in  FIG. 4 . The antenna substrate  30 C is formed by excluding the feed elements  121  from the antenna substrate  30 B illustrated in  FIG. 4 . 
     In this manner, the antenna module  100  may be modified to function as an inverted-F antenna instead of a patch antenna. Thus, the antenna module  100  can have antenna characteristics different from the characteristics of a patch antenna. The antenna module  100  may be modified to function as an antenna (such as a dipole antenna) other than the patch antenna and the inverted-F antenna. 
     Modification Example 4 
       FIG. 6  is a perspective view of an inside of a communication device  10 D according to Modification Example 4. The communication device  10 D includes an antenna substrate  30 D instead of the antenna substrate  30  in the communication device  10 . The antenna substrate  30 D is formed by adding, to the antenna substrate  30 , an overhang portion A 2  that extends in an X-axis negative direction from the mount portion A 0 . In other words, the antenna substrate  30 D includes, besides the overhang portion A 1  extending in the first direction (X-axis positive direction) from the mount portion A 0 , the overhang portion A 2  that extends from the mount portion A 0  in a second direction (X-axis negative direction in an example illustrated in  FIG. 6 ) different from the first direction. 
     The feed element  121  is disposed in the overhang portion A 1 . The heat dissipator  70  is disposed on a lower surface  30   b  in the overhang portion A 1 . Another feed element  121  is disposed in the overhang portion A 2 . Another heat dissipator  70  is disposed on the lower surface  30   b  in the overhang portion A 2 . A ground electrode  122 D extends throughout an antenna substrate  30 D including the mount portion A 0  and the overhang portions A 1  and A 2 . The antenna substrate thus including the overhang portions A 1  and A 2  on both sides of the mount portion A 0  can retain a large area for receiving the feed elements  121  and the ground electrode  122 , and the antenna module  100  can further improve heat dissipation characteristics. 
     Hereinbelow, the feed element  121  and the heat dissipator  70  disposed on the overhang portion A 1  are also respectively described as “a feed element  121 A 1 ” and “a heat dissipator  70 A 1 ”, and the feed element  121  and the heat dissipator  70  disposed on the overhang portion A 2  are also respectively described as “a feed element  121 A 2 ” and “a heat dissipator  70 A 2 ”. 
     The side surface, in the X-axis negative direction, of a heat dissipator  70 A 2  disposed on the overhang portion A 2  is in contact with the housing  11 . Thus, heat of the overhang portion A 2  can be actively released to the housing  11  from the heat dissipator  70 A 2 . While the antenna substrate  30 D is formed from a flexible substrate, the heat dissipator  70 A 2  may have the entire surface in contact with the housing  11  while having the end portion of the overhang portion A 2  in the X-axis negative direction being bent to follow the shape of the housing  11 . 
     “The overhang portion A 1 ”, “the overhang portion A 2 ”, “the feed elements  121 A 1 ”, “the feed elements  121 A 2 ”, “the heat dissipator  70 A 1 ”, and “the heat dissipator  70 A 2 ” according to Modification Example 4 may respectively correspond to “a first overhang portion”, “a second overhang portion”, “a first antenna element”, “a second antenna element”, “a first heat dissipator”, and “a second heat dissipator” in the present disclosure. 
     Modification Example 5 
       FIG. 7  is a perspective view of an inside of a communication device  10 E according to Modification Example 5. The communication device  10 E includes an antenna substrate  30 E instead of the antenna substrate  30 A illustrated in  FIG. 3 . The antenna substrate  30 E is formed by adding, to the antenna substrate  30 A, a via  74  and a ground electrode  122 E. 
     The via  74  has a first end connected to a ground electrode  122 A and a second end connected to the circuit board  40 . The ground electrode  122 A is electrically connected to the circuit board  40  through the via  74 . Thus, heat of the RFIC  110  can be more efficiently transmitted to the overhang portion Al through the via  74  and the ground electrode  122 A. 
     The ground electrode  122 E is disposed closer to the lower surface  30   b  of the antenna substrate  30 E than the ground electrode  122 A of the patch antenna, and is electrically connected to the circuit board  40  at a first end. The ground electrode  122 E electrically connected to the circuit board  40  and disposed closer to the surface of the antenna substrate  30 E than the ground electrode  122 A of the patch antenna can more efficiently transmit heat of the RFIC  110  to the heat dissipator  70 , and can thus further improve heat dissipation characteristics. 
     Modification Example 6 
     Although the antenna substrate  30  illustrated in  FIG. 2  is a rigid substrate or a flexible substrate, the antenna substrate  30  may have a laminate structure including a rigid substrate and a flexible substrate. In this case, the ground electrode  122  may be disposed in the flexible substrate, and the antenna elements  121  may be disposed in the rigid substrate. The rigid substrate may be mounted on the flexible substrate or connected to the flexible substrate by, for example, adhesion. 
     Modification Example 7 
       FIG. 8  is a perspective view of an inside of a communication device  10 F according to Modification Example 7. The communication device  10 F includes an antenna substrate  30 F instead of the antenna substrate  30  illustrated in  FIG. 2 . As in the case of the antenna substrate  30 , the antenna substrate  30 F also includes a mount portion A 0  on which the RF module  60  is mounted and an overhang portion A 1  that extends outward (in the X-axis positive direction) from the mount portion A 0 . 
     The mount portion A 0  of the antenna substrate  30 F is formed by laminating a rigid substrate  31  and a flexible substrate  32 . The rigid substrate  31  is mounted on the flexible substrate  32  or connected to the flexible substrate  32  by, for example, adhesion. The ground electrode  122  is disposed in the flexible substrate  32  in the mount portion A 0 , and the antenna element  121  is disposed in the rigid substrate  31  in the mount portion AU. 
     The overhang portion A 1  of the antenna substrate  30 F includes only the flexible substrate  32  without the rigid substrate  31 . The antenna element  121  in the overhang portion A 1  is disposed in the flexible substrate  32 . The ground electrode  122  extends across the mount portion A 0  and the overhang portion A 1  in the flexible substrate  32 . 
     The overhang portion A 1  of the antenna substrate  30 F includes a first portion A 11  where the antenna element  121  is disposed, a second portion A 12  that is in contact with the housing  11 , and a bend A 13  disposed between the first portion A 11  and the second portion A 12 . More specifically, in the antenna substrate  30 F, an end portion of the overhang portion A 1  in the X-axis positive direction is bent in the Z-axis positive direction and connected to the housing  11 . Thus, the housing  11  covering the antenna module  100  is usable as an aspect of a heat dissipator. 
     As described above, the mount portion A 0  of the antenna substrate  30 F may have a laminate structure including the rigid substrate  31  and the flexible substrate  32 , and the overhang portion A 1  of the antenna substrate  30 F may have a single layer structure including only the flexible substrate  32 . The overhang portion A 1  may be bent and connected to the housing  11 . 
       FIG. 8  illustrates an example where an end portion of the antenna substrate  30 F in the X-axis positive direction is directly connected to the housing  11 . Instead, a heat dissipator may be additionally disposed between the end portion of the antenna substrate  30 F in the X-axis positive direction and the housing  11 . 
     Modification Example 8 
     In the communication device  10  illustrated in  FIG. 2 , the RF module  60  and the shielding case  80  are mounted on the single mount substrate  20 . Instead, the RF module  60  and the shielding case  80  may be respectively mounted on different substrates. 
     The embodiments disclosed herein are mere examples in all respects and should be construed as being nonlimitative. The scope of the present disclosure is defined by the scope of claims instead of the description of the above embodiments, and is intended to include all the changes within the meaning and the scope equivalent to the scope of claims. 
     REFERENCE SIGNS LIST 
     
         
           10 ,  10 A to  10 F communication device 
           11  housing 
           20  mount substrate 
           20   a ,  30   a  upper surface 
           30 ,  30 A to  30 F antenna substrate 
           30   b  lower surface 
           30   c  side surface 
           31  rigid substrate 
           32  flexible substrate 
           40  circuit board 
           50  resin molding member 
           60  RF module 
           70 ,  70 A 1 ,  70 A 2  heat dissipator 
           71 ,  72 ,  73  electrically conductive member 
           74  via 
           80  shielding case 
           81 ,  82  electronic component 
           100  antenna module 
           111 A to  113 D,  117  switch 
           112 AR to  112 DR low-noise amplifier 
           112 AT to  112 DT power amplifier 
           114 A to  114 D attenuator 
           115 A to  115 D phase shifter 
           116  signal multiplexer/demultiplexer 
           118  mixer 
           119  amplifier circuit 
           120  antenna device 
           121 ,  121 A 1 ,  121 A 2  feed element 
           122 ,  122 A,  122 B,  122 C,  122 D ground electrode 
         A 0  mount portion 
         A 1 , A 2  overhang portion 
         A 11  first portion 
         A 12  second portion 
         A 13  bend 
         Pg grounded portion 
         Ps feeder