Antenna module

Abstract

The object is to provide a technology that can reduce the size of an antenna module protruding from the outer surface of a vehicle body and suppress the reduction of an interior passenger space. The antenna module is mounted on a roof of a vehicle and includes a substrate and a plurality of antennas provided on the substrate, wherein the substrate is held in a curved state.

Description

Technical Field

[0001] The present disclosure relates to an antenna module. Background Art

[0002] Patent Document 1 discloses a mounting structure for a vehicle-mounted antenna. In the mounting structure for a vehicle-mounted antenna described in Patent Document 1, an antenna unit is arranged so as to protrude toward the outer surface of a vehicle body.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2008-85386 Summary of the invention

[0006] Problems to be solved by the invention

[0007] It is desirable that the protrusion of the antenna unit from the outer surface of the vehicle body be small. If the protrusion of the antenna unit from the outer surface of the vehicle body is reduced, the interior passenger space may be reduced.

[0008] Therefore, an object of the present invention is to provide a technology capable of reducing the size of an antenna module protruding from the outer surface of a vehicle body and suppressing the reduction of the interior passenger space.

[0009] Technical solutions to solve problems

[0010] The antenna module disclosed herein is mounted on a roof of a vehicle, and includes a substrate and a plurality of antennas disposed on the substrate, wherein the substrate is held in a bent state.

[0011] Effects of the Invention

[0012] According to the present disclosure, it is possible to reduce the size of the antenna module protruding from the outer surface of the vehicle body and suppress the reduction of the interior passenger space. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic front view showing a vehicle on which the antenna module according to the embodiment is mounted.

[0014] Figure 2 It is a schematic side view showing a vehicle on which the antenna module according to the embodiment is mounted.

[0015] Figure 3 It is a schematic front view showing an antenna module according to the embodiment and a mounting structure on a vehicle roof.

[0016] Figure 4 It is an exploded perspective view showing the antenna module according to the embodiment.

[0017] Figure 5It is a schematic front view showing an antenna module according to a modified example and a mounting structure on a vehicle roof. DETAILED DESCRIPTION

[0018] [Description of Embodiments of the Present Disclosure]

[0019] First, embodiments of the present disclosure are listed for description.

[0020] The antenna module of the present disclosure is described as follows.

[0021] (1) An antenna module is mounted on a roof of a vehicle, the antenna module comprising a substrate and a plurality of antennas disposed on the substrate, the substrate being held in a curved state. By mounting the antenna module with the substrate held in a curved state on the roof, the protrusion of the antenna module from the outer surface of the vehicle body is reduced, thereby preventing the reduction of the interior passenger space due to the antenna module.

[0022] (2) The base plate may be curved so that the surface facing outward becomes a convex surface. This can suppress a reduction in the interior passenger space.

[0023] (3) Alternatively, the plurality of antennas may include a first antenna for a first radio wave and a second antenna for a second radio wave having a higher frequency band than the first radio wave, the first antenna and the second antenna being arranged on the convex surface, and the second antenna being arranged in the substrate at a position closer to the top of the convex surface than the first antenna. Generally, radio waves become difficult to diffract as the frequency increases. Even in this case, since the second antenna is arranged in the substrate at a position closer to the top of the convex surface than the first antenna, the second antenna can easily transmit and receive the second radio wave.

[0024] (4) The device may further include a support member for supporting the substrate, wherein the support member is formed in a curved shape, and the substrate is a flexible substrate and is held in a curved state by being supported by the support member. Thus, the substrate can be easily held in a curved state.

[0025] [Details of the embodiments of the present disclosure]

[0026] Specific examples of the antenna module disclosed in the present invention are described below with reference to the accompanying drawings. The present invention is not limited to these examples, but is indicated by the claims, and is intended to include all changes within the meaning and scope equivalent to the claims.

[0027] [Implementation Method]

[0028] Hereinafter, an antenna module according to an embodiment will be described. Figure 1 It is a schematic front view showing a vehicle 80 on which the antenna module 10 according to the embodiment is mounted. Figure 2It is a schematic side view showing a vehicle 80 on which the antenna module 10 according to the embodiment is mounted. Figure 3 It is a schematic front view showing the antenna module 10 according to the embodiment and the mounting structure on the roof 90 . Figure 4 It is an exploded perspective view showing the antenna module 10 according to the embodiment.

[0029] The antenna module 10 is mounted on a roof 90 of a vehicle 80. First, the shape of the roof 90 on which the antenna module 10 is mounted will be described.

[0030] <Roof>

[0031] The roof 90 includes a roof panel 92 and a roof decoration 94. The roof panel 92 is a member that forms the appearance of the vehicle 80. The roof panel 92 is formed in a plate shape using metal or resin as a material. Here, the explanation is given assuming that the roof panel 92 is bent. A through hole 92h is formed in the roof panel 92. The antenna module 10 is installed in a manner embedded in the through hole 92h. Therefore, the antenna module 10 is exposed to the outside. Of course, it is not a necessary structure for the antenna module 10 to be embedded in the through hole 92h of the roof panel 92. The antenna module 10 can also be arranged on the outer surface side of the roof panel 92. In addition, if the roof panel 92 is a member that does not block radio waves, the antenna module 10 can also be arranged on the inner surface side of the roof panel 92.

[0032] The antenna module 10 is mounted on the curved portion of the roof panel 92. That is, the through hole 92h is formed in the curved portion of the roof panel 92. Figure 1 As shown, a portion of the roof panel 92 extending in the width direction of the vehicle 80 (hereinafter referred to as the width direction) may be curved. Figure 2 As shown, the portion of the roof panel 92 extending in the front-rear direction of the vehicle 80 (hereinafter referred to as the front-rear direction) may also be bent. In addition, among the portions of the roof panel 92 where the antenna module 10 is mounted, both the portion extending in the width direction and the portion extending in the front-rear direction may be bent, or only the portion extending in the width direction may be bent, or only the portion extending in the front-rear direction may be bent.

[0033] The roof trim 94 is a member that forms the interior appearance of the vehicle 80. The roof trim 94 is also called a roof lining, a molded ceiling, etc. The roof trim 94 is formed into a plate shape from a material such as resin. The antenna module 10 is arranged outside the roof trim 94.

[0034] <Antenna Module>

[0035] The antenna module 10 includes a substrate 20 and a plurality of antennas 30. Here, the antenna module 10 further includes a housing 40.

[0036] The substrate 20 is a printed circuit substrate 20. The substrate 20 includes an insulator 22 and printed wiring 24. Hereinafter, a case where the substrate 20 is a flexible substrate 20 will be described.

[0037] The insulator 22 includes a substrate on which the printed wiring 24 is printed. The insulator 22 may contain a solder resist or the like. The substrate is formed of a resin material such as a fluororesin, for example. The fluororesin is not particularly limited, and polytetrafluoroethylene (PTFE) or the like may be used.

[0038] The printed wiring 24 is formed on the base. The printed wiring 24 is formed of, for example, copper foil or the like.

[0039] A plurality of antennas 30 are provided on the substrate 20. Each antenna 30 may be a printed component or a mounted component. When the antenna 30 is a printed component, it may be provided integrally with the printed wiring 24, for example. When the antenna 30 is a mounted component, for example, the terminal of the antenna 30 is connected to the printed wiring 24 by welding or the like. When wireless communication is performed between the vehicle 80 and an external communication object, the antenna 30 is a communication antenna on the vehicle 80 side. Each antenna 30 uses an antenna corresponding to a wireless communication system. The wireless communication system is not particularly limited, and may be an Intelligent Transport System (ITS), a Global Positioning System (GPS), a mobile / car phone, a fifth-generation mobile communication system (so-called 5G), and the like. Each antenna 30 corresponds to a different wireless communication system. Therefore, as an antenna module 10, it corresponds to a plurality of wireless communication systems.

[0040] In addition, the frequency band corresponding to each antenna 30 depends on each wireless communication system. For example, in ITS, the 700 MHz band and the 5.8 GHz band are used. In addition, for example, in GPS, the L1 band (1575.42 MHz) and the L2 band (1227.60 MHz) are used. In addition, for example, in mobile / car phones, the 800 MHz band and the 1.5 GHz band are used. In addition, for example, in 5G, the FR1 band (Frequency Range 1) below the 6 GHz band and the FR2 band (Frequency Range 2) above the 24 GHz band can be used.

[0041] Each antenna 30 is connected to the junction box JB via a printed wiring 24. The junction box JB performs power distribution, for example. Circuits required for wireless communication, such as signal converters, oscillators, amplifiers, filters, etc., are appropriately mounted on the substrate 20 or the junction box JB. The junction box JB is connected to the wiring harness WH via a connector C, etc. An opening 42h for connecting the connector C may be formed in the support member 42. The wiring harness WH connects the antenna 30 to the in-vehicle network. As a result, signals related to wireless communication are transmitted between the antenna 30 and the in-vehicle network in a wired manner.

[0042] The housing 40 is a member that accommodates the substrate 20 and the antenna 30. The housing 40 includes a support member 42 and a cover 44.

[0043] The support member 42 is a member that supports the substrate 20. Here, the support member 42 is formed in a plate shape. The support member 42 is formed in a curved state. The support member 42 has a rigidity that can maintain the curved state.

[0044] The support member 42 is arranged below the substrate 20 along the vertical direction. By placing the substrate 20 on the support member 42, the support member 42 is in a state of supporting the substrate 20. It is preferable that the substrate 20 is positioned and fixed relative to the support member 42. For example, the substrate 20 is attached to the support member 42, or is positioned and fixed by being locked to the support member 42 by a locking component. In the case where the substrate 20 is positioned and fixed to the support member 42, the substrate 20 may also be arranged below the support member 42.

[0045] The cover 44 covers the substrate 20 and the antenna 30 supported by the support member 42 . Here, the cover 44 is formed in a box shape with an open bottom. The opening of the cover 44 is closed by the support member 42 .

[0046] Here, the housing 40 is mounted on the roof panel 92. Figure 3 In the example shown, the housing 40 is fitted into the through hole 92h of the roof panel 92 from the inner surface side of the vehicle 80. The housing 40 is provided with a flange 46. Figure 3 In the example shown, the support member 42 is set to be larger than the cover 44, and the outer edge of the support member 42 serves as a flange 46. The flange 46 is fixed to the roof panel 92 by bolt fastening or the like.

[0047] The component located outside the antenna 30 in the shell 40 (here, the cover 44) is formed of a material that does not block radio waves, such as glass or resin. The component located inside the antenna 30 in the shell 40 (here, the support component 42) can be formed of a material that does not block radio waves, or can be formed of a material that blocks radio waves, such as metal. In the case where the component located inside the antenna 30 in the shell 40 is formed of a material that does not block radio waves, the component located inside the antenna 30 and the component located outside the antenna 30 in the shell 40 can be formed of the same material or different materials.

[0048] It is preferable to provide a sealing portion between the supporting member 42 and the cover 44. This prevents water and the like from entering between the supporting member 42 and the cover 44. Similarly, it is preferable to provide a sealing portion between the shell 40 and the roof panel 92. This prevents water and the like from entering between the shell 40 and the roof panel 92. One sealing portion may also serve as both a sealing portion between the supporting member 42 and the cover 44 and a sealing portion between the shell 40 and the roof panel 92. It is also possible to provide a sealing portion between the supporting member 42 and the cover 44 and a sealing portion between the shell 40 and the roof panel 92 separately. The sealing portion may be a lip preformed from a material such as rubber, or a sealing portion formed by filling a softened resin such as an adhesive into a gap and curing it.

[0049] In the antenna module 10, the substrate 20 is held in a bent state. Here, since the substrate 20 is a flexible substrate 20, it is difficult for the substrate 20 itself to be held in a bent state. The substrate 20 is held in a bent state by being supported by the support member 42.

[0050] The base plate 20 and the support member 42 are curved in the same manner as the roof panel 92. Here, the housing 40 is also curved in the same manner as the roof panel 92. The outer surface of the housing 40 (at Figure 3 The outer surface of the housing 40 (in the figure, the outer surface of the cover 44) is not recessed or protruded inwardly or outwardly relative to the outer surface of the roof panel 92. Figure 3 The outer surface of the housing 40 (in the figure) is flush with the outer surface of the roof panel 92. Figure 3 The outer surface of the cover 44 in the middle may also be recessed or protruded in the inner and outer directions relative to the outer surface of the roof panel 92.

[0051] Here, the curvature (curvature) K (unit: 1 / m) can be obtained by the formula K=1 / R using the curvature radius (curvature radius) R (unit: m). In addition, the ratio of the curvature degree between the substrate 20 and the roof panel 92 is set to the consistency rate I. The consistency rate I can be expressed by the formula I=K1 / K2 using the curvature K1 of the substrate 20 and the curvature K2 of the roof panel 92. The curvature K2 of the roof panel 92 can be expressed by the curvature of the peripheral portion of the through hole 92h formed in the roof panel 92.

[0052] There may be curvatures K1 and K2 in the vehicle width direction ( Figure 1 The left-right direction of the paper) and the front-back direction ( Figure 2 In this case, the curvatures K1, K2 and the consistency rate I in the vehicle width direction are respectively set to the curvatures K1a, K2a and the consistency rate Ia (where Ia = K1a / K2a). In addition, the curvatures K1, K2 and the consistency rate I in the front-rear direction are respectively set to the curvatures K1b, K2b and the consistency rate Ib (where Ib = K1b / K2b).

[0053] The values ​​of the consistency rates I, Ia, and Ib are not particularly limited and can be set appropriately. For example, the values ​​of the consistency rates I, Ia, and Ib can be greater than 0.5 and less than 1.5, or greater than 0.7 and less than 1.3, or greater than 0.9 and less than 1.1. The values ​​of the consistency rates Ia and Ib can be the same or different. In addition, the allowable ranges set for the values ​​of the consistency rates Ia and Ib can be the same or different. For example, the value of the consistency rate Ia can be greater than 0.5 and less than 1.5, and the value of the consistency rate Ib can be greater than 0.7 and less than 1.3. In addition, in the case where the substrate 20 is bent only in either the vehicle width direction or the front-to-back direction, the allowable range of the consistency rate I can be set only for the bending direction. In addition, even in the case where the substrate 20 is bent in both the vehicle width direction and the front-to-back direction, the allowable range of only one of the consistency rates Ia and Ib can be set. That is, it is appropriate to set the allowable range of at least one of the consistency rates Ia and Ib.

[0054] The substrate 20 is curved so that the surface facing outward becomes a convex surface. The plurality of antennas 30 are arranged on the convex surface in a planar positional relationship.

[0055] The plurality of antennas 30 include a first antenna 30A and a second antenna 30B. The first antenna 30A is an antenna 30 for a first radio wave. The second antenna 30B is an antenna 30 for a second radio wave. The frequency band of the second radio wave is higher than that of the first radio wave. The second antenna 30B is disposed in the substrate 20 at a position closer to the top of the convex surface than the first antenna 30A. In addition, the so-called top refers to the portion farthest from the plane along the normal direction when the curved substrate 20 is placed on a plane. In addition, the substrate 20 is sometimes installed in the vehicle 80 in an inclined state. Therefore, in the vehicle 80, the top is not limited to the highest position in the vertical direction in the substrate 20.

[0056] In addition, when the multiple antennas 30 include three or more communication antennas 30 based on different frequency bands, the first antenna 30A can be the communication antenna 30 based on the lowest frequency band among the multiple antennas 30, and the second antenna 30B can be the communication antenna 30 based on the highest frequency band among the multiple antennas 30.

[0057] In the portion of the roof panel 92 where the antenna module 10 is mounted, only one of the portion extending in the width direction and the portion extending in the front-rear direction is bent, and the antenna module 10 is bent in a manner corresponding thereto, and the top portion may extend linearly in the direction in which it is not bent. Specifically, in the case where the roof panel 92 and the antenna module 10 are bent as shown in FIG. Figure 3 When the portion extending in the horizontal direction of the paper is curved as shown, the top portion extends in the front-back direction of the paper. In this case, the plurality of antennas 30 can be arranged in a state of being arranged at the top portion.

[0058] When the plurality of antennas 30 are arranged in a state of being arranged in a row at the top, the antenna 30 based on the lowest frequency band among the plurality of antennas 30 arranged at the top is provided at a position that is the closest distance to the edge of the substrate 20 among the plurality of antennas 30 arranged at the top. In addition, the antenna 30 based on the highest frequency band among the plurality of antennas 30 arranged at the top is provided at a position that is the farthest distance from the edge of the substrate 20 among the plurality of antennas 30 arranged at the top. Thus, the antenna 30 based on the highest frequency band can also perform communication well.

[0059] The antenna module 10 is rectangular in a plan view. The long side of the antenna module 10 is the vehicle width direction, and the short side is set to the front-rear direction. Of course, the long side of the antenna module 10 may also be the front-rear direction, and the short side may be set to the vehicle width direction.

[0060] <Effects, etc.>

[0061] According to the antenna module 10 configured as described above, the substrate 20 is held in a curved state. By attaching the antenna module 10 to the roof 90 , the protrusion of the antenna module 10 from the vehicle body outer surface is reduced, thereby preventing the interior passenger space from being reduced due to the antenna module 10 .

[0062] The base plate 20 is curved so that the surface facing outward becomes a convex surface. Therefore, the roof trim 94 can also be formed in a shape that convexes outward corresponding to the base plate 20. This can suppress the reduction of the indoor passenger space.

[0063] Generally, radio waves have stronger straightness as the frequency increases, and become difficult to diffract. Even in this case, the second antenna 30B is arranged at a position closer to the top of the convex surface than the first antenna 30A in the substrate 20. Therefore, even if there is an obstacle to the radio waves around the antenna module 10, the second radio waves can be relatively suppressed from interfering with the obstacle. Therefore, the second antenna 30B can communicate well.

[0064] In addition, since the frequency band of the first radio wave is lower than that of the second radio wave, it is easy to diffract. Therefore, even if there are obstacles to the radio waves around the antenna module 10, the first radio wave is easy to diffract and propagate. Therefore, the first antenna 30A can also communicate well. The communication environment based on radio waves in the antenna module 10 is improved.

[0065] Since the flexible substrate 20 is held in a curved state by being supported by the support member 42 , the substrate 20 can be easily held in the curved state.

[0066] In addition, the substrate 20 is held in a bent state before the antenna module 10 is mounted on the vehicle 80. Therefore, by mounting the antenna module 10 on the vehicle 80, the substrate 20 is disposed in a bent state in the vehicle 80.

[0067] [Modifications]

[0068] Figure 5 1 is a schematic front view showing an antenna module 110 according to a modification and a mounting structure on a roof 190. The antenna module 110 according to the modification is configured to be fitted into a through hole 192h of a roof panel 192 from the outer surface side of the vehicle 80.

[0069] A recess 193 is formed in the roof panel 192. A through hole 192h is formed at the bottom of the recess 193. The opening of the through hole 192h is smaller than the opening of the recess 193. The housing 140 in the antenna module 110 includes a supporting member 142 and a cover 144. The supporting member 142 is formed in a box shape with an upper opening. The substrate 20 and the antenna 30 are accommodated in the supporting member 142. The cover 144 is formed in a plate shape. The cover 144 blocks the opening of the supporting member 142. The cover 144 is formed to be larger than the supporting member 142. The outer edge of the cover 144 becomes a flange 146. The flange 146 contacts the peripheral edge of the through hole 192h in the bottom surface of the recess 193.

[0070] The shape of the housing is not limited to the above-mentioned shape. For example, both the support member and the cover may be formed into a box shape. In addition, at least one of the support member and the cover may be formed into a box shape with a flange.

[0071] In the embodiment, the substrate 20 is described as a flexible substrate 20, but this is not a necessary structure. The substrate may also be a rigid substrate. In this case, the rigid substrate itself is formed into a curved shape, and preferably has a rigidity to the extent that the curved shape can be maintained. When the substrate is a rigid substrate, a supporting member may be provided, or a supporting member may not be provided.

[0072] In the embodiment, the substrate 20 is described as being curved so that the surface facing outward becomes a convex surface, but this is not an essential structure. The substrate may be curved so that the surface facing outward becomes a concave surface.

[0073] In addition, the respective configurations described in the above-mentioned embodiment and the respective modifications may be appropriately combined as long as they do not contradict each other.

[0074] Description of Reference Numerals

[0075] 10, 110 antenna module

[0076] 20 substrate

[0077] 22 Insulator

[0078] 24 Printed wiring

[0079] 30 Antenna

[0080] 30A First Antenna

[0081] 30B Second Antenna

[0082] 40, 140 housing

[0083] 42, 142 Supporting members

[0084] 44, 144 hood

[0085] 46, 146 flange

[0086] 80 Vehicles

[0087] 90, 190 Roof

[0088] 92, 192 Roof Panel

[0089] 92h, 192h through hole

[0090] 193 concavity

[0091] 94 Roof trim

[0092] JB Junction Box

[0093] C Connector

[0094] WH harness.

Claims

1. An antenna module installed on the roof of a vehicle, The antenna module comprises: substrate; A plurality of antennas disposed on the substrate; and a housing including a supporting member for supporting the substrate and a cover for covering the substrate and the antenna, The roof is a component located above the interior passenger space of the vehicle. The support member is a member formed in a curved shape, provided separately from the roof panel of the roof, and having rigidity capable of maintaining the curved shape. The substrate is a flexible substrate and is supported by the support member so as to be held in a curved state similar to the roof panel. The shell is also curved in the same manner as the roof panel. A through hole is formed in the curved portion of the roof panel, The housing is inserted into the through hole so that an outer surface of the cover is flush with or recessed relative to an outer surface of the roof panel.

2. The antenna module according to claim 1, wherein: The substrate is curved so that an outwardly facing surface becomes a convex surface.

3. The antenna module according to claim 2, wherein: The plurality of antennas include a first antenna for a first radio wave and a second antenna for a second radio wave having a frequency band higher than that of the first radio wave. The first antenna and the second antenna are arranged on the convex surface, The second antenna is provided in the substrate at a position closer to the top of the convex surface than the first antenna.

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