JPH1117428A - High frequency glass antenna for automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve a sensitivity further than that of a case only with a glass antenna by electrically connecting the glass antenna to a microstrip antenna or a chip-shaped and laminated planar antenna. SOLUTION: A high frequency glass antenna consists of a bipolar glass antenna 1 provided in the window glass of an automobile, the microstrip antenna or the laminated antenna (mini-antenna) 2, a radiation side power feeding point 4, a grounded point 5, a radiation side connecting line 8, a grounded side connecting line 9, the power feeding electrode 24 of the mini-antenna 24 and the grounded electrode 25 of the mini-antenna 2. Then, in this antenna, the bipoler glass antenna is provided in the window glass plate of automobile and the mini-antenna 2 is electrically connected to the bipolar glass antenna 1. The glass antenna 1 is connected to the mini-antenna 2 in terms of DC. But they can be connected in terms of a high frequency by a capacitor or by permitting the both to be adjacent so as to be connected by capacitance without being restricted by the former connection.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to, for example, a vehicle communication means using an 800 MHz band (810 to 960 MHz) or a 1.5 GHz band (1.429 to 1.501 GHz) of a car telephone, a GPS artificial satellite communication, and the like. The present invention relates to a high-frequency glass antenna for an automobile suitable for a vehicle.

[0002]

2. Description of the Related Art Conventionally, a pole antenna and a microstrip antenna have been used as antennas for transmitting and receiving radio waves used for automobile telephones and GPS satellite communication. In recent years, glass antennas provided on window glasses of automobiles have been used.

[0003]

Although a pole antenna can provide practical performance as an antenna, it is usually used in a form protruding from a mounted vehicle body, so that it is cumbersome in appearance and has aesthetic problem. There was a problem that it could be mischievous. Further, the microstrip antenna has strong directivity, and the transmission / reception characteristics may be significantly deteriorated depending on the direction in which the automobile is facing.

In view of the above problems, a glass antenna provided on a rear window glass of an automobile shown in FIG. 4 has been developed.
In FIG. 4, 3 is a receiver, 4 is a radiation side feeding point, 5 is a ground point, a radiating element 6, ground elements 7, 10
Is a connector, 11 is a coaxial cable, 12 is a rear window glass plate, and 13 is a hot wire for anti-fog.

FIG. 5 shows the receiving sensitivity of the glass antenna of FIG. 15 is the receiving sensitivity of the glass antenna of FIG.
Although it has reached a practical level, there is a problem that the reception sensitivity is somewhat insufficient, and good reception cannot be performed in a weak electric field area.

[0006]

DISCLOSURE OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and a bipolar glass antenna is provided on a window glass plate of an automobile. Provided is a high-frequency glass antenna for an automobile, wherein a laminated plate antenna is electrically connected.

The present invention provides the above high-frequency glass antenna for automobiles, wherein the microstrip antenna or the laminated plate antenna is chip-shaped. The present invention provides the high-frequency glass antenna for an automobile in which the glass antenna and the microstrip antenna or the laminated plate antenna are connected by a combiner, and the output of the combiner is connected to a receiver.

According to the present invention, the tuning frequency of the glass antenna is a frequency in a first frequency band, and the tuning frequency of the microstrip antenna or the tuning frequency of the laminated plate antenna is a frequency in the second frequency band. Provide high frequency glass antenna for use.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 is a basic configuration diagram of a high-frequency glass antenna for a vehicle according to the present invention. In FIG. 1, reference numeral 1 denotes a bipolar glass antenna provided on a window glass of an automobile, 2 denotes a microstrip antenna or a laminated antenna (hereinafter, sometimes referred to as a mini antenna), 4 denotes a radiation-side feeding point, and 5 denotes a ground point. , 8 is a radiation side connection line, 9 is a ground side connection line, 24 is a feed electrode of the mini antenna 2, and 25 is a ground electrode of the mini antenna 2.

[0010] Here, the microstrip antenna is a device in which an antenna conductor and a ground electrode are provided on a dielectric substrate or a dielectric substrate, and the antenna conductor and the ground electrode are not DC-connected. An antenna that uses a voltage between the power supply electrode and the ground electrode connected to the antenna as a reception signal and applies a transmission signal between the power supply electrode and the ground electrode connected to the antenna conductor during transmission. .

[0011] A laminated plate antenna is a multilayer substrate in which a ground conductor is provided on a dielectric substrate having a multilayer structure or a dielectric substrate having a multilayer structure, and a plurality of antenna conductors of various shapes are sandwiched between dielectric layers. The antenna conductor and the ground conductor are not connected in a DC manner, and the voltage between the antenna conductor and the ground conductor is used as a reception signal during reception, and the voltage between the antenna conductor and the ground conductor is used during transmission. An antenna that applies a transmission signal in between.

In FIG. 1, the glass antenna 1 and the mini antenna 2 are connected in a DC manner. However, the present invention is not limited to this, and the connection may be made at a high frequency by a capacitor or by capacitively coupling the two close to each other.

FIG. 2 shows a configuration diagram of a typical example of the present invention. In FIG. 2, 7 is a ground side element, 10 is a connector, and 61 is a loop-shaped phase inversion line. The mini-antenna 2 of FIG. 2 used a chip-shaped one for miniaturization.
The mini antenna 2 shown in FIG. 2 is connected to the glass antenna 1 in a direct current manner by a radiation side connection line 8 and a ground side connection line 9. The glass antenna 1 and the mini antenna 2 are connected to the receiver 3 via a connector 10 and a coaxial cable 11.

The shape of the glass antenna according to the present invention is not limited to that shown in FIG. 2, but may be any shape. Further, the window glass plate provided with the high-frequency glass antenna for automobile of the present invention is not limited to the rear window glass plate, but may be another window glass plate.

FIG. 8 shows a block diagram of another type of the present invention different from FIG. In FIG. 8, reference numeral 17 denotes a synthesizer. The glass antenna 1 and the chip-shaped mini antenna 2 are composed of a synthesizer 1
7, and the output of the synthesizer 17 is connected to the receiver 3. FIG. 9 is a configuration diagram of a representative example of the one shown in FIG.

In FIG. 9, a chip-shaped mini antenna 2
And the ground electrode 25 of the chip-shaped mini-antenna 2 are connected to the input of the combiner 17 and combined with the output of the glass antenna. Although the connector, the coaxial cable, and the receiver are omitted in FIG. 9, the connector is actually connected to the output unit of the synthesizer.

[0017]

【Example】

(Example 1) A high frequency glass antenna for an automobile as shown in FIG. 2 was manufactured. The size of the rear window glass plate 12 is approximately 600 in the vertical direction.
mm, approximately 1100 mm in the lateral direction. The anti-fog heat wire 13 is provided on almost the entire rear window glass plate 12.

The dimensions of the radiation-side feed point 4 and the ground point 5 are 10
mm × 10 mm, the total length of the radiating element 6 is 200 m
m, the circumference of the loop-shaped phase inversion line 61 is 220 mm,
The total length of the earth element 7 was 30 mm, and was adjusted so as to be tuned to the 800 MHz band which is the first frequency band.

The size of the chip-shaped microstrip antenna or the chip-shaped laminated plate antenna is 15 mm × 10
The length of the radiation side connection line 8 was 10 mm, and the length of the earth side connection line 9 was 50 mm. The dimensions of the connector 10 are 20
mm × 10 mm × 10 mm, and the dimension of the coaxial cable 11 was 1500 mm.

FIG. 3 shows the receiving sensitivity. In FIG. 3, 1
5 is the receiving sensitivity of only the glass antenna 1, 16 is the receiving sensitivity of only the chip-shaped microstrip antenna or the chip-shaped laminated plate antenna, and 14 is the receiving sensitivity when both are connected.

The receiving sensitivity is somewhat insufficient only with the glass antenna, and the receiving sensitivity of the chip-shaped microstrip antenna or the laminated plate antenna alone is lowered by being mounted on the window glass plate. It can be seen that the reception sensitivity has been increased by connecting. FIG.
As shown in the figure, about 1
The dB reception sensitivity has increased.

(Example 2) A radiation-side feed point 4, a feed electrode 24, and a high-frequency glass antenna for an automobile as shown in FIG.
The dimensions of the ground point 5 and the ground electrode 25 are 10 mm x 7 mm
The dimensions of the synthesizer 17 are 15 mm × 10 mm × 8 mm
Thus, the glass antenna 1 is connected to the chip-shaped microstrip antenna or the chip-shaped laminated plate antenna.

The glass antenna 1 was adjusted so as to tune to the 800 MHz band, and the microstrip antenna or the chip-shaped laminated plate antenna used was tuned to the 800 MHz band. FIG. 10 shows the receiving sensitivity. In FIG. 10, 15 is the reception sensitivity of the glass antenna 1, 16 is the reception sensitivity of the chip-shaped microstrip antenna or the chip-shaped laminated plate antenna, and 18 is the reception sensitivity of the output of the combiner 17.

The reception sensitivity is somewhat insufficient only with the glass antenna, and the reception sensitivity is reduced by mounting the antenna on the window glass plate only with the chip-shaped microstrip antenna or the laminated plate antenna. It can be seen that the reception sensitivity is increased by combining FIG.
As shown by 0, the reception sensitivity was increased by about 1 dB as compared with the case where only the glass antenna was used.

(Example 3) For a vehicle having the same configuration as that of Example 1 except that a chip-shaped microstrip antenna or a chip-shaped laminated plate antenna tuned to the 1.5 GHz band which is the second frequency band was used. A high frequency glass antenna was manufactured.

FIG. 11 shows the receiving sensitivity. In FIG. 11, reference numeral 19 denotes the reception sensitivity of the glass antenna adjusted so as to tune to the 800 MHz band. The reception sensitivity is high in the 800 MHz band, but the reception sensitivity is low in the 1.5 GHz band. Reference numeral 20 denotes the receiving sensitivity of a chip-shaped microstrip antenna or a chip-shaped laminated plate antenna tuned to the 1.5 GHz band. The receiving sensitivity is high in the 1.5 GHz band, but is low in the 800 MHz band. I have.

Reference numeral 21 denotes a combination of the two, and in the 800 MHz band, the receiving sensitivity is higher than that of the glass antenna, and is 1.5 GHz.
In the band, the receiving sensitivity was higher than that of the chip-shaped microstrip antenna or the chip-shaped laminated plate antenna.

(Example 4) 1.5 GHz for a chip-shaped microstrip antenna or a chip-shaped laminated plate antenna
An automobile high-frequency glass antenna having the same configuration as that of Example 2 was manufactured except that an antenna tuned to the band was used.

FIG. 12 shows the receiving sensitivity. In FIG. 12, reference numeral 22 denotes the receiving sensitivity of the glass antenna adjusted to tune to the 1.5 GHz band. The receiving sensitivity is high in the 1.5 GHz band, but is low in the 800 MHz band. Reference numeral 23 denotes the reception sensitivity of the chip-shaped microstrip antenna or the chip-shaped laminated plate antenna tuned to the 800 MHz band, and the reception sensitivity is obtained in the 800 MHz band. In the 1.5 GHz band, the receiving sensitivity is low.

Reference numeral 24 denotes an output obtained by combining the two by the combiner 17. The reception sensitivity is higher in the 800 MHz band than in the chip-shaped microstrip antenna or the chip-shaped laminated plate antenna, and is higher than the glass antenna in the 1.5 GHz band. Became higher.

Example 5 A small chip microstrip antenna or a chip laminated plate antenna using a dielectric or the like shown in FIG. 6 was mounted on a window glass plate. FIG. 7 shows the receiving sensitivity of the chip-shaped microstrip antenna or the chip-shaped laminated plate antenna of FIG. In FIG. 7, reference numeral 16 denotes the receiving sensitivity of a chip-shaped microstrip antenna or a chip-shaped laminated plate antenna.

A chip-shaped microstrip antenna or a chip-shaped laminated plate antenna can provide a practical level of receiving sensitivity when used in an empty space, but when mounted on a window glass plate, the receiving sensitivity decreases. It was found that good reception was not possible in the weak electric field area.

[0033]

According to the present invention, since the glass antenna is electrically connected to the microstrip antenna or the chip-shaped laminated plate antenna, the antenna induced voltage increases,
Reception sensitivity and transmission performance are improved as compared with the case of using only a glass antenna, or the case of using only a chip-shaped microstrip antenna or a chip-shaped laminated plate antenna.

Further, by dividing the tuning frequency band of the glass antenna and the microstrip antenna or the chip-shaped laminated plate antenna into a first frequency band and a second frequency band, an antenna usable in a plurality of frequency bands. Is obtained.

[Brief description of the drawings]

FIG. 1 is a basic configuration diagram of a high-frequency glass antenna for a vehicle according to the present invention.

FIG. 2 is a configuration diagram of a typical example of a high-frequency glass antenna for an automobile of the present invention.

FIG. 3 is a characteristic diagram of reception sensitivity of Example 1.

FIG. 4 is a configuration diagram of a conventional glass antenna.

FIG. 5 is a characteristic diagram of reception sensitivity of a conventional glass antenna.

FIG. 6 is a configuration diagram when only a chip-shaped microstrip antenna or a chip-shaped laminated plate antenna is provided on a rear window glass plate.

FIG. 7 shows the reception sensitivity of the chip-shaped microstrip antenna or the chip-shaped laminated plate antenna of Example 5.

FIG. 8 is a block diagram of another type of the present invention different from FIG. 1;

FIG. 9 is a configuration diagram of a representative example of the one shown in FIG.

FIG. 10 is a characteristic diagram of reception sensitivity in Example 2.

FIG. 11 is a characteristic diagram of reception sensitivity in Example 3;

FIG. 12 is a characteristic diagram of reception sensitivity in Example 4.

[Explanation of symbols]

1: glass antenna 2: microstrip antenna or chip-shaped laminated plate antenna 3: receiver 4: radiation-side feeding point 5: ground point 6: radiation element 7: ground-side element 8: radiation-side connection wire 9: ground-side Connection line 10: Connector 11: Coaxial cable 12: Rear window glass plate 13: Anti-fog heat wire 17: Synthesizer

Claims (4)

[Claims] 1. A high frequency wave for an automobile, wherein a bipolar glass antenna is provided on a window glass plate of the automobile, and a microstrip antenna or a laminated plate antenna is electrically connected to the bipolar glass antenna. Glass antenna. 2. The high frequency glass antenna for an automobile according to claim 1, wherein the microstrip antenna or the laminated plate antenna is chip-shaped. 3. A glass antenna and a microstrip antenna or a laminated plate antenna are connected by a combiner,
The output of the combiner is connected to a receiver.
A high-frequency glass antenna for an automobile as described in the above. 4. The tuning frequency of the glass antenna is a frequency in the first frequency band, and the tuning frequency of the microstrip antenna or the tuning frequency of the laminated plate antenna is a frequency in the second frequency band. 4. The high frequency glass antenna for an automobile according to 2, 3 or 4.