Patent Application
20220013888
The disclosure relates to a vehicle antenna.
Japanese Unexamined Patent Application Publication No. 2009-284366 discloses a technique relating to a roof antenna such as a shark-fin shaped antenna mounted on a roof, which deals with various types of wireless communication systems and devices relating to AM or FM radio broadcasts, the Global Positioning System (GPS), the Electronic Toll Collection System (ETC), the Vehicle Information and Communication System (VICS (registered trademark)), ground wave digital television broadcasts, inter-vehicle communication, and the like.
However, in a case of this roof antenna, it is required to lay an antenna cable connected to the antenna in a vehicle and to connect the antenna cable to a device in a system exemplified by those described above.
Thus, this causes inconvenience such as increase in cost as well as time-consuming work of laying the antenna cable.
Further, in a case of a mobile phone, a smartphone, or the like that cannot be directly connected to the antenna cable, radio waves are partially blocked due to a metal plate or the like constituting a vehicle body, which causes a problem of reception sensitivity degradation in the vehicle.
It is an object of the disclosure to provide a vehicle antenna capable of improving reception sensitivity of a mobile phone, a smartphone, or the like without requiring work of laying an antenna cable in a vehicle.
A vehicle antenna according to the disclosure is a vehicle antenna mounted on a vehicle. The vehicle antenna includes a first antenna portion configured to receive a radio wave signal, the first antenna portion being provided on a roof of the vehicle, and a second antenna portion configured to emit a radio wave signal into the vehicle, the second antenna portion being provided in the vehicle. The first antenna portion is a monopole antenna. The second antenna portion is a flat plate antenna. The first antenna portion and the second antenna portion are electrically connected to each other via a co-axial cable.
With this, a radio wave received by the first antenna portion can be emitted into the vehicle by the second antenna portion. Thus, reception sensitivity of a mobile phone, a smartphone, or the like can be improved without requiring work of laying an antenna cable in the vehicle.
The monopole antenna of the vehicle antenna according to the disclosure may be a shark-fin shaped antenna.
With this, an external radio wave can be received with high sensitivity without impairing the aesthetic appearance.
The flat plate antenna of the vehicle antenna according to the disclosure may include a dielectric body having a plate-like shape, a first electrode provided to one peripheral portion of the dielectric body, and a second electrode provided to the other peripheral portion facing the one peripheral portion of the dielectric body. The first electrode may be connected to one end of a core wire of the co-axial cable, and the second electrode may be connected to a part of an outer cover wire of the co-axial cable.
With this, a radio wave received by the first antenna can be emitted efficiently into the vehicle via the flat plate antenna.
The other end of the core wire of the co-axial cable of the vehicle antenna according to the disclosure may be connected t to the monopole antenna, and a part of the outer cover wire of the co-axial cable may be earth-connected to a conductive portion of a vehicle body.
With this, a radio wave received by the monopole antenna can be emitted efficiently into the vehicle via the flat plate antenna.
The second antenna portion of the vehicle antenna according to the disclosure may be arranged in a space formed between a ceiling plate and the roof of the vehicle.
With this, the second antenna portion can be arranged without reducing a cabin space.
According to the disclosure, there can be provided the vehicle antenna capable of improving reception sensitivity of a mobile phone, a smartphone, or the like without requiring work of laying an antenna cable in a vehicle.
With reference to the drawings, a vehicle antenna AS according to this embodiment is described below in detail.
With reference to
As illustrated in
As illustrated in
The first antenna portion A1 and the second antenna portion A2 are electrically connected to each other via a co-axial cable 100.
More specifically, as illustrated in
As illustrated in
Meanwhile, as illustrated in
One end of the core wire 101 of the co-axial cable 100 is connected to the first electrode E1 by a joining portion 115 such as solder, and an outer cover wire 102 of the co-axial cable 100 is connected to the second electrode E2 by a joining portion 116 such as solder.
As described above, the other end of the core wire 101 of the co-axial cable 100 is connected to the antenna element 401 (402) of the shark-fin shaped antenna Ala (Alb), and a part of the outer cover wire 102 of the co-axial cable 100 is earth-connected to a conductive portion of a vehicle body B.
As illustrated in
In the second antenna portion A2, the flat plate surface of the plate-like dielectric body 150 may be parallel with the ceiling plate 300, and may be attached to the ceiling plate 300. With this, even when the space 301 is smaller, the second antenna portion A2 can be arranged while saving a space.
The first antenna portion A1 has antenna characteristics as illustrated in
The second antenna portion A2 have antenna characteristics as illustrated in
With this configuration, the vehicle antenna AS according to this embodiment is capable of causing the second antenna portion A2 to emit, into the vehicle, a radio wave received by the first antenna portion A1. Thus, reception sensitivity of a mobile phone, a smartphone, or the like can be improved without requiring work of laying an antenna cable in a vehicle.
With reference to
In the vehicle antenna AS10, a leakage cable 500 being a second antenna A3a is arranged in place of the usual co-axial cable 100, in the space 301 between the roof 10 and the ceiling plate 300.
The leakage cable 500 is configured so that a cover portion is drilled to have a plurality of openings (slits) 501 and that the outer cover wire 102 is exposed from each of the openings (slits) 501.
With this, a radio wave received by the first antenna A1 is emitted into the vehicle through each of the openings (slits) 501 of the leakage cable 500 being the second antenna A3a.
Therefore, a radio wave received by the first antenna portion A1 can be emitted into the vehicle by the second antenna portion A3a. Thus, reception sensitivity of a mobile phone, a smartphone, or the like can be improved without requiring work of laying an antenna cable in a vehicle.
With reference to
In the vehicle antenna AS11, the leakage cable 500 being a second antenna A3b is arranged in place of the usual co-axial cable 100, along the vehicle inner side of the ceiling plate 300.
The leakage cable 500 is configured so that the cover portion is drilled to have the plurality of openings (slits) 501 and that the outer cover wire 102 is exposed from each of the openings (slits) 501.
With this, a radio wave received by the first antenna A1 is emitted into the vehicle through each of the openings (slits) 501 of the leakage cable 500 being the second antenna A3b.
Therefore, a radio wave received by the first antenna portion A1 can be emitted into the vehicle by the second antenna portion A3a. Thus, reception sensitivity of a mobile phone, a smartphone, or the like can be improved without requiring work of laying an antenna cable in a vehicle.
The vehicle antenna and the like of the disclosure are described above based on the illustrated embodiments. However, the disclosure is not limited thereto, and the configurations of the respective elements may be replaced with freely-selected configurations having similar functions.
The entire contents of Japanese patent application No. 2019-081763 (filed on Apr. 23, 2019) are herein invoked.
While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel embodiments described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2019-081763 | Apr 2019 | JP | national |
The present application is a continuation of International Application No. PCT/JP2020/016575, filed on Apr. 15, 2020, and based upon and claims the benefit of priority from Japanese Patent Application No. 2019-081763, filed on Apr. 23, 2019, the entire contents of which are incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/JP2020/016575 | Apr 2020 | US |
| Child | 17487523 | US |
