JPH0794925A - Glass antenna - Google Patents

Abstract

PURPOSE:To make it possible to receive a fine radio wave from a GPS satellite and to use this glass antenna as an antenna for an automibile telephone system or the like by constituting one element of the glass antenna like a U shape and the other like a horizontal wire or a U shape and arranging both the elements close to each other. CONSTITUTION:Cloudiness preventing heating wires 2, a glass antenna 3 arranged on a lower margin part under the wires 2 and constituted of the 1st element 31 having a U-shaped element connecting a vertical wire on both the ends of a horizontal wire and a T-shaped element connected to the horizontal wire of the U-shaped element and the 2nd element 32 consisting of a horizontal wire arranged along the horizontal wire of the 1st element 31 and a feeding point 4 for the 1st element are printed out and burned like a screen together with an antenna 5 arranged on the upper margin part of the wires 2 allowed to receive other FM radio broadcasting waves or the like on the inside of plate glass for an automobile by a conductive paste to form a glass antenna system. After mounting this window glass on the rear part of the automibile, an inner wire conductor 7 of a coaxial cable is connected to the feeding point 4 of the 1st element 31 and the center part of the 2nd element 32 is connected to an external conductor as a feeding point.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a glass antenna provided on a window glass for vehicles such as automobiles, ships and airplanes.
Especially GPS (Global Positioning)
The present invention relates to a glass antenna suitable for receiving weak radio waves from a satellite, and transmitting and receiving radio waves in the ultra-high frequency band such as car telephones, personal radios, and commercial radios.

[0002]

2. Description of the Related Art Conventionally, a microstrip antenna is known as an antenna for receiving weak radio waves from GPS satellites, as well as a quadrature dipole antenna, a helical antenna, etc. Because of the structure, not only is it unfavorable in terms of safety and appearance, but it also interferes with car washing,
Furthermore, there were drawbacks such as the possibility of breakage.

The present invention has been made in view of the above points, is suitable for receiving a weak radio wave from a GPS satellite, and is used for a mobile phone, a personal radio, and a personal handy phone that is being put into practical use. It is an object of the present invention to provide a glass antenna that can also be used as an antenna for.

[0004]

DISCLOSURE OF THE INVENTION The present invention relates to a glass antenna arranged on a window glass for a moving body, wherein a U-shaped element having vertical filaments connected to both ends of a horizontal filament and the U-shaped element. At least a first element comprising a T-shaped element or a Y-shaped element connected to a horizontal filament of the element and a second element comprising a horizontal filament disposed along the first element; The inner conductor of the coaxial cable is connected to the first element, and the outer conductor is connected to the second element. An auxiliary element consisting of vertical filaments is provided at both ends of the horizontal filament of the second element. It is preferable to add.

[0005]

In order to receive the circularly polarized radio waves transmitted from the GPS satellites, the present inventors preferably use antennas in which one of them has a U-shape and the other has a horizontal line or a U-shape and are brought close to each other. By adding a T-shaped element or a Y-shaped element to the inner C-shaped element as the first element, the directional characteristic can be received by the GPS satellite in any direction. To improve.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the drawings. 1 is a front view showing a first embodiment in which the glass antenna of the present invention is provided on a rear window glass for an automobile, FIG. 2 is a front view showing another embodiment, and FIGS. 3 to 6 are the first embodiments of the present invention. 7 is a detailed view of an essential part of the antenna portion of the fourth embodiment, FIG.
FIG. 4 is a directional characteristic diagram of the antenna in the first embodiment.

Example 1 This is an example in which a single plate glass is mounted as a rear window glass of a vehicle. As shown in FIGS. 1 and 3, a heating wire 2 for anti-fog and anti-fog are provided on the inside of the plate glass 1 for the car. In the lower margin portion of the heating wire for heating, a first element 3 having a U-shaped element in which vertical wires are connected to both ends of the horizontal wire and a T-shaped element connected to the horizontal wire of the U-shaped element ₁ and the glass antenna 3 composed of the second element 3 ₂ which is arranged along the horizontal filament of the first element and is composed of the horizontal filament, the feeding point 4 of the first element, the upper margin of the heating filament for defrosting It is formed by screen printing and firing with a conductive paste together with another antenna 5 for receiving an FM radio broadcast wave and the like provided in the section.

After mounting such a window glass on the rear part,
The inner conducting wire 7 of the coaxial cable 6 is connected to the feeding point 4 of the first element, and the outer conducting wire 8 is connected with the center portion of the second element 3 ₂ as the feeding point.

The dimensions of each part of the glass antenna thus obtained are a = 90 mm, b ₁ = b ₂ = 30 mm, c
= 35 mm, d ₁ = d ₂ = 42 mm, e = 90 mm, f
= 5 mm, g = 4.5 mm
The directional characteristics shown in FIG. 7 are obtained by measuring the directional characteristics when a right-handed circularly polarized wave of 542 GHz is received and showing the relative ratio when a general microstrip antenna commercially available and put to practical use is set to 0 dB. It was confirmed that the characteristic diagram was obtained and that it could be sufficiently put to practical use.

Embodiment 2 Embodiment 2 shown in FIG. 4 is a T-shaped element of the first element.
The vertical filament of the ment is formed by two
Rement 3₂Length h at both ends of the horizontal line₁= H ₂= 35
mm vertical line for auxiliary element 9₁, 9₂Added as
It has the same configuration and dimensions as in Example 1 except that
It

With such an antenna, 1.575
The directional characteristic when receiving a right-handed circularly polarized wave of 42 GHz is measured, and the relative ratio when a general microstrip antenna commercially available and put to practical use is set to 0 dB is equivalent to the first embodiment. The directional characteristic diagram of was obtained.

Embodiments 3 to 4 In Embodiment 3 shown in FIG. 5, the elements connected to the horizontal filaments of the first element are formed in a Y shape, and in Embodiment 4 shown in FIG. Element is auxiliary element 10
₁ and 10 ₂ are added, the horizontal line of the second element is formed to have the same width as the other line, and the feeding point 11 is formed to be wide. The other configurations are the same as those of the first embodiment. It was configured, and it was confirmed that almost the same reception characteristics as in Example 2 were obtained.

As described above with reference to the preferred embodiment,
The invention is not limited to these, and various applications are possible.
It is possible. For the first element,
The horizontal length a of the ment is 50 mm to 200 mm,
Vertical length preferably in the range of 80 mm to 100 mm
b₁, B ₂Is appropriately selected within the range of 20 mm to 50 mm.
Good.

For the second element, is the horizontal length e approximately the same as the horizontal length a of the first element?
The length may be increased up to about mm. Regarding the auxiliary element, it can be put to practical use without the auxiliary elements 9 ₁ and 9 ₂ connected to both ends of the second element, but it is preferable to provide it because it has the effect of improving the directional characteristics. May be arranged such that the end thereof is substantially level with the end of the vertical filament of the first element. Although other auxiliary elements are not necessarily required, various elements can be added for the purpose of improving directional characteristics, adjusting impedance, and improving reception gain.

The location of the antenna 3 is not limited to the central portion of the lower portion of the heating wire for anti-fog on the rear window glass of the vehicle, but also to the side portion of the lower margin portion or the upper margin portion as shown in FIG. It may be provided on the front window glass or the sunroof. In addition to the vehicle, it may be provided in a window of an aircraft or a ship.

Further, when the transmission / reception gain in the vertical polarization of the personal radio having a center frequency of 904 MHz was measured, the result close to the transmission / reception gain of the practically used pole antenna was obtained.

When a laminated glass is used as the rear window glass, a fine metal wire such as a copper wire may be embedded in the intermediate film.

[0018]

The glass antenna of the present invention can receive a weak radio wave from a GPS satellite at a practical level even if the arrival direction of the GPS satellite changes, by forming the first element into a unique shape. It can be used as an antenna for telephones and personal radios.

[Brief description of drawings]

FIG. 1 is a front view showing a first embodiment in which a glass antenna of the present invention is provided on a rear window glass for an automobile.

FIG. 2 is a front view showing another embodiment in which the glass antenna of the present invention is provided on a rear window glass for an automobile.

FIG. 3 is a detailed view of a main part showing only an antenna part according to the first embodiment of the present invention.

FIG. 4 is a detailed view of a main part showing only an antenna part according to a second embodiment of the present invention.

FIG. 5 is a detailed view of a main part showing only an antenna part according to the third embodiment of the present invention.

FIG. 6 is a detailed view of a main part showing only an antenna part according to a fourth embodiment of the present invention.

FIG. 7 is a directional characteristic diagram of the antenna according to the first embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Plate glass 2 Heating wire for anti-fog 3 ₁ 1st element 3 ₂ 2nd element 3 Antenna 4 of this invention 4, 11 Feed point 5 Another antenna 6 Coaxial cable 7 Internal conductor 8 External conductor 9 ₁ , 9 ₂ 10 ₁ , 10 ₂ Auxiliary element

Claims (2)

[Claims] 1. A glass antenna disposed on a window glass for a moving body, wherein a U-shaped element having vertical filaments connected to both ends of a horizontal filament and a T connected to the horizontal filament of the U-shaped element. The first element comprises a letter-shaped element or a Y-shaped element and a second element constituted by a horizontal filament arranged along the horizontal filament of the first element, and the first element is provided with a coaxial cable. A glass antenna characterized in that an inner conductor is connected to an outer conductor to the second element. 2. The glass antenna according to claim 1, wherein vertical auxiliary elements are added to both ends of the second element.