JPH0294904A - Windshield antenna for vehicle - Google Patents

Abstract

PURPOSE:To obtain a windshield antenna having high reception gain for waves in a wide band from an AM radio broadcasting wave to a wave in a UHF band by combining a specific transparent antenna and a wire antenna. CONSTITUTION:First, a feeder bar 2 is formed at the side of the laminating face of a plate glass 1 for the outside of a vehicle, and a transparent conductive film composed of the multilayer film of Ag, Zn, and ZnO is formed on a large area equivalent to a 1/2 area from the upper part of a windowpane or above as a transparent antenna 3. For the side of the non-laminating face of an intra- vehicle side 1', together with plural heating wires 4 for preventing dimming, two sets of wire antennas 5 and feeding points 6 and a feeding point 7 for the transparent antenna are formed on a blank part in the lower part of the transparent antenna. Further, the two plate glasses 1 and 1' are laminated through an interlayer 8, and laminated glass is obtained. Thus, no only the waves, the AM radio broadcasting wave, an FM radio broadcasting wave, and a television proadcasting wave in a VHF band but also other waves extending over the wide range of bands such as other television broadcasting wave, an automobile telephone system wave, and a personal radio wave in the UHF band can be received.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a glass antenna for vehicles such as automobiles, and more particularly to a glass antenna that combines a transparent antenna and a wire antenna.

[Conventional technology]

Transparent antennas installed on the front or rear windows of automobiles have become popular in recent years because they occupy a large antenna area and have a wide reception band, and many proposals have been made.

[Problem that the invention seeks to solve]

By the way, recently, cars have come to be equipped with various wireless devices other than radio receivers, such as television receivers, car phones, and personal wireless devices, and accordingly, there is a demand for antennas to transmit and receive these radio waves. It has reached the point where it will be done.

However, with only a conventional transparent antenna, even though it is a broadband antenna, the band that can receive it is AM radio broadcast waves, domestic and foreign FM radio broadcast waves, and TV broadcast waves in the V HF band. Radio waves, for example,
U HF television, car phone, personal radio, etc.
The gain was low for transmitting and receiving radio waves in the HF band (300 to 3000 MIlz) or higher, making reception difficult.

The present invention was made in view of the above points, and an object of the present invention is to provide a glass antenna with high reception gain for extremely wide band radio waves from AM radio broadcast waves to UPI-1 band radio waves. shall be.

Means for Solving Problem C] The present invention provides a glass antenna provided on a vehicle window glass, in which a transparent antenna is formed so as to have a blank space at the bottom from the top side of the window glass to 1/2 or more of the area. Additionally, a linear antenna for receiving at least radio waves of a higher frequency than the transparent antenna is formed in the blank space.

[Effect]

The transparent antenna is formed over a wide area of 172 or more from the top of the window glass, so it can receive radio waves ranging from AM radio broadcast waves to FM radio broadcast waves and TV broadcast waves in the VHF band. Even if the antenna area is small, the linear antenna formed in the margin of the UI
Radio waves in the IF band have short wavelengths, so they can be received well.

Also, it is better to arrange the transparent antenna at the top of the window glass and the wire antenna at the bottom of the transparent antenna, as it is better to arrange them at the upper part of the window glass. This is based on the reason that the linear antenna has relatively less influence.

Furthermore, depending on the conductive material constituting the transparent antenna, it can be given a heat ray reflecting function, and 0.65% of the window area
A wide area of about ~0.75 improves antenna performance and can be effectively used as a heat insulating glass, which is more effective.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to the drawings.

Figures 1 to 3 are front views showing the glass antennas when mounted on the rear window glass of a car in Examples 1 to 3, respectively, +al is the inside glass, fbl is the outside glass, and Figure 4 is 1 (Example 1); FIG.

Example 1 As shown in FIGS. 1 and 4, first, a power supply bar 2 was printed with conductive paste on the mating surface side of the vehicle exterior plate glass l.
The antenna 3 is formed by firing, and then a transparent conductive film made of a multilayer film of Ag, Zn, and ZnO is formed as the transparent antenna 3.

On the non-matching surface side of the inside 1'' of the vehicle, there are two sets of wire antennas 5, a feeding point 6, and a plurality of heating wires 4 for anti-fogging.
And a terminal seat for the transparent antenna, that is, a power feeding point 7 is formed by printing and firing a conductive paste.

Next, these two glass plates 1.1' are laminated with an interlayer film 8 of polyvinyl butyral or the like interposed therebetween, and a laminated glass is obtained by ordinary autoclave treatment.

At the same time, the transparent antenna 3 and the feeding point 7 are connected using the copper foil connecting piece 9.

The thus obtained laminated glass is installed as a rear window glass of an automobile and is led from the power supply points 6 and 7 to a radio receiver or a TV receiver by a lead wire or a feeder.

In the vehicle glass antenna with such a configuration, the dimensions of each part are A1 1,180 mm, A2 = 1,44011
B=760u, T+=L140 Dragon, T2・1.315
FM radio broadcast waves and television broadcast waves are made by u,,I(,=530 厘鳳, h+=210i quantity, h z=20 璽鳳, I(□=60-heavy, h a=140 tsuru). The reception gain at the time of reception is expressed as the gain difference (hereinafter referred to as dipole ratio) with the reception gain of a standard dipole antenna being OdB.The average of domestic FM radio broadcast waves from 76MHz to 90MHz, 88MHz to 108MHz Table 1 shows the average of foreign FM radio broadcast waves, the average of channels 1 to 12 of TV broadcast waves, the average of 7 channels of VHF band, and the average of TV broadcast waves of UHF band 470 Ml1z to 770 Ml1z. The reception gain of a good rear glass antenna is 12
0 dB, -21 dB, -22 dB, -22 dB, so transparent antennas are used for domestic and foreign FM radio broadcast waves and TV broadcast waves in the VHF band, while wire antennas are used for foreign FM radio broadcast waves and TV broadcast waves in the VHF band. HF band and U
It can be seen that this is a good antenna for the HF band.

Table 1 (Gouipol ratio: dB) Table 2 (Gouipol ratio: d[l) Also, the reception gain when receiving AM radio broadcast waves is 1
When the m-length whip antenna is expressed as OdB, the gain difference is -9, Od[l, and since the receiving gain of the conventional good rear glass antenna is 110 dBR1&, it can be seen that it is a good antenna.

Example 2 - Absolutely 3 In Example 2 shown in FIG. 2 and Example 3 shown in FIG. 3, the position of the feeding point 7 of the transparent antenna 3 is changed from Example 1, and
Although the pattern of the wire antenna has been changed, the shape, dimensions, and glass dimensions of the transparent antenna 3 are almost the same.
When the reception gain of HF and UHF television broadcast waves was measured, the results shown in Table 2 were obtained.

(Example 2: Example 2, Example 3: Example 3) As is clear from these results, it can be seen that the antenna is as good as that of Example 1.

Although the present invention has been described above using preferred embodiments, the present invention is not limited to these embodiments, and various applications are possible.

For a transparent antenna, its occupied area is the ratio of the effective height H of the antenna to the height of the window glass, i.e. H1/
In each example, B indicates approximately 0.7, but if it is 0.5 or more, it can be used as a transparent antenna and has a wide band property.
If the value is 75 or more, the area occupied by the linear antenna becomes smaller and the reception gain decreases, so if it is within the range of 0.5 to 0.75, it can be put to practical use. When a heat ray reflection function is imparted to a transparent antenna, a range of 0.65 to 0.75 is more preferable because heat insulation performance can be expected.

The transparent conductive film forming the transparent antenna can be made of various films such as an ITO film, a NESA film, a multilayer film of Ag and TiO□, etc., in addition to the one in the embodiment. In addition to the one provided directly on the mating surface side of the glass, it may also be provided directly on the mating surface of the car interior glass plate, or one in which a transparent film coated with a transparent conductive film is sandwiched between two intermediate films.

As for the wire antenna, any pattern suitable for receiving radio waves on the UHF band side or FM radio broadcast waves may be used, and two sets of wire antennas may be arranged symmetrically as in Example 11 and Example 3. If provided, antennas with substantially the same reception gain for radio waves in each frequency band and different directivity characteristics can be obtained, so it is more suitable to perform diversity reception with these antennas.

These antennas can also be used as transmitting and receiving antennas for car telephones and personal radios.

Further, the wire antenna may be printed and fired using a conductive paste and provided on the mating surface side of the vehicle exterior glass plate, that is, on the same surface as the transparent antenna, or may be provided on an intermediate film using a thin metal wire such as copper.

In addition, these antennas can be attached not only to the rear window glass, but also to the front window glass if the wire antenna is made small. It may be provided.

〔Effect of the invention〕

By combining a transparent antenna and a wire antenna, the present invention can be used not only for AM radio broadcast waves, FM radio broadcast waves, and TV broadcast waves in the VHF band, but also for a very wide range of applications such as UHF band TV broadcast waves, car telephones, personal wireless, etc. It enables reception (including transmission in the case of car phones and personal radios) over the following bands, and can also be expected to have a heat-insulating effect if the transparent antenna is given a heat ray reflection function.

4,

[Brief explanation of the drawing]

FIGS. 1 to 3 are front views showing the glass anti-glare when the rear window glass of an automobile is installed in Examples 1 to 3 of the present invention, respectively (al is the inside plate glass, (bl is the outside plate glass, 4 is a partial cross-sectional view of the longitudinal center portion of FIG. 1 (Embodiment 1). Vehicle outside plate glass 1゛Vehicle inner plate glass transparent antenna wire antenna

Claims (1)

[Claims] In a glass antenna installed on a vehicle window glass, a transparent antenna is formed so as to have a blank area at the bottom from the top side of the window glass to 1/2 or more of the area, and a radio wave with a higher frequency than that of the transparent antenna is provided in the blank area. What is claimed is: 1. A glass antenna for a vehicle, comprising a wire antenna for receiving at least the following: