阅读说明：本技术 车辆用天线 (Antenna for vehicle ) 是由 土屋和彦 于 2020-04-15 设计创作，主要内容包括：一种车辆用天线(AS),搭载于车辆,具备：第一天线部(A1),其设置于车辆的车顶(10)上,并接收电波信号；以及第二天线部(A2),其设置于车辆内,并向车内发射电波信号,第一天线部(A1)由单极天线构成,第二天线部(A2)由平板天线构成,第一天线部(A1)与第二天线部(A2)经由同轴电缆(100)电连接。(An Antenna (AS) for a vehicle, which is mounted on a vehicle, is provided with: a first antenna unit (A1) that is provided on a roof (10) of a vehicle and that receives a radio wave signal; and a second antenna unit (A2) that is provided in the vehicle and that emits radio signals into the vehicle, wherein the first antenna unit (A1) is configured from a monopole antenna, the second antenna unit (A2) is configured from a patch antenna, and the first antenna unit (A1) and the second antenna unit (A2) are electrically connected via a coaxial cable (100).)

1. A vehicle antenna mounted on a vehicle, the vehicle antenna comprising:

a first antenna unit that is provided on a roof of the vehicle and receives a radio wave signal; and

a second antenna unit that is provided in the vehicle and emits a radio wave signal to the inside of the vehicle,

the first antenna portion is constituted by a monopole antenna,

the second antenna portion is constituted by a flat antenna,

the first antenna portion and the second antenna portion are electrically connected via a coaxial cable.

2. The antenna for a vehicle according to claim 1,

the monopole antenna is composed of a shark fin antenna.

3. The antenna for a vehicle according to claim 1 or 2,

the planar antenna is provided with:

a plate-like dielectric;

a first electrode provided at one peripheral portion of the dielectric; and

a second electrode provided at the other peripheral portion of the dielectric body, the other peripheral portion being opposed to the peripheral portion;

the first electrode is connected to one end of a core wire of the coaxial cable,

the second electrode is connected to a portion of an outer coated wire of the coaxial cable.

4. The antenna for a vehicle according to claim 3,

the other end of the core wire of the coaxial cable is connected with the monopole antenna,

and one part of the outer coating wire of the coaxial cable is in grounding connection with the conductive part of the vehicle body.

5. The antenna for a vehicle according to any one of claims 1 to 4,

the second antenna portion is disposed in a space formed between a roof panel and a roof of the vehicle.

Technical Field

The present invention relates to an antenna for a vehicle.

Background

Patent document 1 discloses a technology relating to a roof antenna such as a shark fin antenna mounted on a roof of a vehicle, and the technology is applicable to various wireless communication systems and devices such as AM, FM radio broadcasting, Global Positioning System (GPS), automatic toll collection system (ETC), road traffic information communication system (VICS (registered trademark)), terrestrial digital television broadcasting, and vehicle-to-vehicle communication.

Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. 2009-284366

Disclosure of Invention

Technical problem to be solved by the invention

However, the roof antenna needs to be connected to the various systems and other devices by wiring an antenna cable connected to the antenna in the vehicle interior.

Therefore, there is a disadvantage that wiring of the antenna cable is troublesome and the cost increases.

In addition, in a mobile phone, a smartphone, or the like that cannot be directly connected to an antenna cable, there is a problem that a part of radio waves is shielded by an influence of a metal plate or the like constituting a vehicle body, and reception sensitivity in the vehicle interior is lowered.

The invention aims to provide an antenna for a vehicle, which can improve the receiving sensitivity of a mobile phone, a smart phone and the like without arranging an antenna cable in the vehicle.

Means for solving the problems

The present invention provides a vehicle antenna mounted on a vehicle, the vehicle antenna including: a first antenna unit that is provided on a roof of the vehicle and receives a radio wave signal; and a second antenna unit that is provided in the vehicle and that emits a radio wave signal to the inside of the vehicle; the first antenna portion is configured by a monopole antenna, the second antenna portion is configured by a patch antenna, and the first antenna portion and the second antenna portion are electrically connected via a coaxial cable.

Thus, the radio wave received by the first antenna unit can be radiated to the inside of the vehicle by the second antenna unit, and the reception sensitivity of the mobile phone, the smartphone, or the like can be improved without wiring an antenna cable in the vehicle.

The monopole antenna of the vehicle antenna according to the present invention may be a shark fin antenna.

This allows external radio waves to be received with high sensitivity without impairing the aesthetic appearance.

The planar antenna of the vehicle antenna according to the present invention may further include: a plate-like dielectric; a first electrode provided at one peripheral portion of the dielectric; and a second electrode provided at the other peripheral portion of the dielectric body, the other peripheral portion being opposed to the peripheral portion; the first electrode is connected to one end of a core wire of the coaxial cable, and the second electrode is connected to a part of an outer covered wire of the coaxial cable.

This enables the radio wave received by the first antenna unit to be efficiently radiated into the vehicle via the patch antenna.

In the vehicle antenna according to the present invention, the other end of the core wire of the coaxial cable may be connected to the monopole antenna, and a part of the outer covering wire of the coaxial cable may be grounded to the conductive portion of the vehicle body.

This makes it possible to efficiently radiate radio waves received by the monopole antenna into the vehicle via the patch antenna.

The second antenna portion of the vehicle antenna according to the present invention may be disposed in a space formed between a roof panel and a roof of the vehicle.

This allows the second antenna unit to be disposed without narrowing the vehicle interior space.

Effects of the invention

According to the present invention, it is possible to provide an antenna for a vehicle, which can improve the reception sensitivity of a mobile phone, a smartphone, or the like without wiring an antenna cable in the vehicle.

Drawings

Fig. 1 is a side view showing a vehicle mounted with a vehicle antenna according to an embodiment.

Fig. 2 is a plan view showing a vehicle mounted with the vehicle antenna according to the embodiment.

Fig. 3 is a schematic configuration diagram showing a schematic configuration of the vehicle antenna according to the embodiment.

Fig. 4A is a cross-sectional view showing a structural example of a shark fin antenna constituting a part of the vehicle antenna according to the embodiment.

Fig. 4B is a cross-sectional view showing a structural example of a shark fin antenna constituting a part of the vehicle antenna according to the embodiment.

Fig. 5A is an antenna characteristic diagram of the first antenna portion.

Fig. 5B is an antenna characteristic diagram of the first antenna portion.

Fig. 5C is an antenna characteristic diagram of the first antenna portion.

Fig. 6A is an antenna characteristic diagram of the second antenna portion.

Fig. 6B is an antenna characteristic diagram of the second antenna portion.

Fig. 7 is a schematic configuration diagram showing a schematic configuration of a vehicle antenna according to another configuration (1).

Fig. 8 is a schematic configuration diagram showing a schematic configuration of a vehicle antenna according to another configuration (2).

Detailed Description

Hereinafter, the vehicle antenna AS according to the present embodiment will be described in detail with reference to the drawings.

An embodiment of the present invention will be described with reference to fig. 1 to 8.

AS shown in fig. 1 and the like, a shark fin antenna (monopole antenna) a1, which is a first antenna constituting a part of a vehicle antenna AS, is provided on the roof of a vehicle V. The first antenna a1 functions to receive radio waves outside the vehicle.

AS shown in fig. 3 and the like, a patch antenna (also referred to AS a patch antenna or a microstrip antenna) a2 AS a second antenna constituting a part of the vehicle antenna AS is provided in the vehicle V. The second antenna a2 functions to radiate radio waves into the vehicle.

The first antenna section a1 and the second antenna section a2 are electrically connected via a coaxial cable 100.

More specifically, as shown in fig. 4A, a shark fin antenna (monopole antenna) A1a according to one configuration example is constituted by a shark fin-shaped case 400, a coil-shaped antenna element 401 disposed in the case 400, and the like. The lower end of the coil-shaped antenna element 401 is connected to the core wire 101 of the coaxial cable 100.

As shown in fig. 4B, a shark fin antenna (monopole antenna) A1B according to another configuration example is composed of a shark fin-shaped case 400 and a rod-shaped antenna element 402 disposed in the case 400. The lower end of the rod-shaped antenna element 402 is connected to the core wire 101 of the coaxial cable 100.

On the other hand, as shown in fig. 3, the patch antenna a2 as the second antenna includes: a plate-like dielectric (e.g., ceramic plate, etc.) 150; a first electrode E1 provided on one peripheral edge 150a of the dielectric 150; and a second electrode E2 provided on the other peripheral edge 150b of the dielectric 150, which is opposed to the peripheral edge 150 a.

One end of the core wire 101 of the coaxial cable 100 is connected to the first electrode E1 by a joint 115 such as solder, and the outer sheath wire 102 of the coaxial cable 100 is connected to the second electrode E2 by a joint 116 such as solder.

As described above, the other end of the core wire 101 of the coaxial cable 100 is connected to the antenna element 401(402) of the shark fin antenna A1a (A1B), and a part of the outer covered wire 102 of the coaxial cable 100 is grounded to the conductive part of the vehicle body B.

In the vehicle antenna AS according to the present embodiment, AS shown in fig. 3, the second antenna section a2 is disposed in the space 301 formed between the roof panel 300 and the roof 10 of the vehicle V, and therefore the second antenna section a2 can be disposed without narrowing the vehicle interior space.

The second antenna portion a2 may be formed by bonding the plate surface of the plate-like dielectric member 150 to the top plate 300 in parallel with the top plate 300. Thus, even if the space 301 is narrower, the second antenna portion a2 can be disposed in a space-saving manner.

The first antenna portion a1 has antenna characteristics as shown in fig. 5A to C.

Fig. 5A is a diagram showing the orientation of the first antenna portion a1, fig. 5B is a diagram showing the vertical polarization directivity, and fig. 5C is a diagram showing the horizontal polarization directivity.

The second antenna portion a2 has antenna characteristics as shown in fig. 6A and 6B.

Fig. 6A is a diagram showing the orientation and the like of the second antenna portion a2, and fig. 6B is a diagram showing circular polarization directivity.

With such a configuration, the vehicle antenna AS according to the present embodiment can radiate radio waves received by the first antenna unit a1 into the vehicle through the second antenna unit a2, and thus, it is not necessary to wire an antenna cable in the vehicle, and the reception sensitivity of a mobile phone, a smartphone, or the like can be improved.

With reference to fig. 7, a configuration of a vehicle antenna AS10 according to another configuration will be described. Note that the same components AS those of the vehicle antenna AS according to the present embodiment are denoted by the same reference numerals, and redundant description thereof is omitted.

In the vehicle antenna AS10, a leaky cable 500 AS a second antenna A3a is disposed in place of the normal coaxial cable 100 in the space 301 between the roof 10 and the roof panel 300.

The leaky cable 500 is configured such that a plurality of openings (slits) 501 are provided through the covering portion, and the outer covering wire 102 is exposed from each opening (slit) 501.

Thereby, the radio wave received by the first antenna a1 is radiated into the vehicle from each opening (slit) 501 of the leaky cable 500 as the second antenna A3 a.

Therefore, the radio wave received by the first antenna unit a1 can be radiated into the vehicle through the second antenna unit A3a, and the reception sensitivity of the mobile phone, the smartphone, or the like can be improved without wiring an antenna cable in the vehicle.

With reference to fig. 8, a configuration of a vehicle antenna AS11 according to another configuration will be described. The same components AS those of the vehicle antenna AS according to the present embodiment are denoted by the same reference numerals, and redundant description thereof is omitted.

In the vehicle antenna AS11, a leaky cable 500 AS a second antenna A3b is arranged along the vehicle interior side of the roof panel 300 instead of the normal coaxial cable 100.

The leaky cable 500 is configured such that a plurality of openings (slits) 501 are provided through the covering portion, and the outer covering wire 102 is exposed from each opening (slit) 501.

Thereby, the radio wave received by the first antenna a1 is radiated into the vehicle from each opening (slit) 501 of the leaky cable 500 as the second antenna A3 b.

Therefore, the radio wave received by the first antenna unit a1 can be radiated into the vehicle through the second antenna unit A3a, and the reception sensitivity of the mobile phone, the smartphone, or the like can be improved without wiring an antenna cable in the vehicle.

Although the vehicle antenna and the like of the present invention have been described above based on the illustrated embodiments, the present invention is not limited thereto, and the configuration of each part may be replaced with any configuration having the same function.

The entire contents of Japanese patent application No. 2019-081763 (application No.: 4/23/2019) are incorporated herein by reference.

While several embodiments of the present invention have been described above, these embodiments are provided as examples and are not intended to limit the scope of the invention. These new embodiments can be implemented in other various ways, and various omissions, substitutions, and changes can be made without departing from the spirit of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalent scope thereof.