JP3199201B2 - Glass antenna - Google Patents

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.
In particular, GPS (Global Positioning)
The present invention relates to a glass antenna suitable for receiving a weak radio wave from a System satellite and transmitting and receiving a radio wave in a very high frequency band such as a mobile phone, a personal radio, and a business radio.

[0002]

2. Description of the Related Art Conventionally, microstrip antennas, as well as orthogonal dipole antennas and helical antennas, are known as antennas for receiving weak radio waves from GPS satellites. Because it has a structure that is not only unfavorable in terms of safety and appearance, it also becomes an obstacle when washing the car,
Further, there is a disadvantage that there is a possibility of breakage.

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

[0004]

SUMMARY OF THE INVENTION The present invention receives a right-handed circularly polarized wave from a GPS satellite disposed on a window glass for a mobile object.
A glass antenna, one of which is a first element composed of a U-shaped element in which vertical filaments are connected to both ends of a horizontal filament, and the other is an element composed of a horizontal filament,
Or a second element composed of a U-shaped element in which auxiliary elements composed of vertical lines are added to both ends of the horizontal line, the horizontal lines of the second element approaching each other along the horizontal line of the first element And the inner conductor of the coaxial cable in the first element,
An external conductor is connected to the second element, and the center of the V-shaped element or the U-shaped element is added to a horizontal line of the first element at a feeding point of the first element. When connected, it is preferable for receiving radio waves from GPS satellites.

[0005]

In order to receive right-handed circularly polarized radio waves transmitted from a GPS satellite, the present inventors preferably use antennas in which one has a U-shape and the other has a horizontal line or a U-shape and is brought close to each other. And a V-shaped or U-shaped element is added to the inner U-shaped element to form the first element, thereby obtaining a GP.
This is to improve the directivity so that the S satellite can be received in any direction.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 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. FIG. 1 is a detailed view of a main part showing an antenna part of the seventh embodiment.
0 is a directional pattern of the antenna according to the second embodiment.

Example 1 This is an example in which a veneer glass is mounted as a rear window glass of a vehicle. As shown in FIGS. 1 and 3, a heating wire 2 for fogging prevention and an antifogging A first element 3 having a U-shaped element having vertical lines connected to both ends of a horizontal line and a V-shaped element connected to the horizontal line of the U-shaped element is provided in a lower margin portion of the heating line. ₁ and the second element 3 ₂ glass antenna 3 comprised consisting horizontal strip disposed along a horizontal strip of the first element, the feed point 4 of the first element, the heating filament top margin for antifogging It is formed by screen printing and baking with a conductive paste together with another antenna 5 for receiving another FM radio broadcast wave provided in the unit.

After attaching such a window glass to the rear,
The feeding point 4 of the first element is connected to the internal conductor 7 of the coaxial cable 6, to connect the external lead wire 8 a second element 3 ₂ in the center as a feeding point.

The dimensions of each part of the glass antenna thus obtained are a = 92 mm, b ₁ = b ₂ = 30 mm, c
₁ = c ₂ = 47 mm, d = 100 mm, e = 5 mm, f
= 1.57542 GHz by using 4.5 mm
FIG. 10 shows the directivity characteristics when receiving the right-handed circularly polarized wave of FIG. 10 and shows the relative ratio when a general microstrip antenna which is commercially available and practically used is set to 0 dB.
The results almost the same as those of the directional characteristic diagram of Example 2 shown in FIG.

[0010] Example 2 shown in Embodiment 2 Figure 4, the second element 3 _second width 5m
m, length g ₁ = g ₂ at both ends of a 100 mm long horizontal line
= Vertical auxiliary line element of 35mm 9 _1, 9 ₂ and then
The configuration and dimensions are the same as those of the first embodiment except for the addition.

With such an antenna, 1.575
The directivity characteristic when receiving 42 GHz right-handed circularly polarized wave is measured, and the directivity characteristic shown in FIG. 10 is shown as a relative ratio when a commercially available and practically used general microstrip antenna is set to 0 dB. The result was as shown in the figure, and it was confirmed that the film could be sufficiently used practically.

Embodiments 3 to 7 Embodiment 3 shown in FIG. 5 is a V-shaped element of the antenna of Embodiment 2.
At the tip of the element, additional auxiliary elements 10 ₁ , 10 ₂
Example 4 shown in FIG. 6 is a first element
7 has the same configuration as that of the second embodiment except that two sets of V-shaped elements are provided. In the fifth embodiment shown in FIG. 7, an auxiliary antenna 11 ₁ is further provided at the tip of the V-shaped element of the antenna of the second embodiment. 11 ₂ obtained by adding, example 6 illustrated in FIG. 8
FIG. 9 shows a modification of the V-shape of the first element, in which two straight lines do not intersect at the position of the feed point, are slightly spaced, and the auxiliary elements 12 ₁ and 12 ₂ are added to the tips . In the embodiment 7 shown, the elements connected to the horizontal stripes of the first element are U-shaped, and the width of the horizontal stripes of the second element is formed to be the same width as the other filaments, so that the feeding point 13 is widened. , And it was confirmed that reception characteristics almost equivalent to those of Example 2 were obtained.

As described above, the preferred embodiment has been described.
The invention is not limited to these, and various applications
It is possible. For the first element, the U-shaped element
The length a of the horizontal streak is 50 mm to 200 mm, preferably
Preferably, in the range of 80mm to 100mm, vertical length
b₁, B _TwoIs appropriately selected within the range of 20 mm to 50 mm.
Just fine.

For the second element, the horizontal length d is about the same as the horizontal length a of the first element,
The length may be increased up to about mm. The auxiliary element can be put to practical use without the auxiliary elements 9 ₁ and 9 ₂ connected to both ends of the second element. However, it is preferable to provide the auxiliary element because it has an effect of improving directional characteristics. May be such that the ends are substantially flush with the ends of the vertical stripes 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, improving reception gain, and the like.

The location of the antenna 3 is not only in the center of the lower margin of the heating wire for fogging in the rear window glass of the vehicle, but also in the side of the lower margin or in the upper margin as shown in FIG. May be provided on the front window glass or the sunroof. Moreover, you may provide in windows, such as an aircraft and a ship, besides a vehicle.

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

When a laminated glass is used as the rear window glass, a thin 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 its arrival direction changes by forming the first element into a unique shape. It can be used as an antenna for telephones and personal radio.

[Brief description of the 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 main part detailed view showing only an antenna part according to the first embodiment of the present invention.

FIG. 4 is a main part detailed view showing only an antenna part in Embodiment 2 of the present invention.

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

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

FIG. 7 is a main part detailed view showing only an antenna part according to a fifth embodiment of the present invention.

FIG. 8 is a main part detailed view showing only an antenna part according to a sixth embodiment of the present invention.

FIG. 9 is a main part detailed view showing only an antenna part according to a seventh embodiment of the present invention.

FIG. 10 is a directional characteristic diagram of the antenna according to the second embodiment of the present invention.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 sheet glass 2 heating wire for anti-fog 3 ₁ first element 3 ₂ second element 3 antenna of the present invention 4 feed point 5 another antenna 6 coaxial cable 7 internal conductor 8 external conductor 9 ₁ , 9 _{2 to} 12 ₁ , 12 ₂ Auxiliary element

Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H01Q 1/32

Claims (2)

(57) [Claims] 1. A GPS satellite disposed on a window glass for a mobile object.
A glass antenna for receiving a right-handed circularly polarized wave from, the first element comprising a U-shaped element which connects the vertical strip across the horizontal strip length 50~200mm one, the other A second element consisting of a horizontal element having the same length as that of the first element or having a length equal to or longer than 20 mm, or a U-shaped element having auxiliary elements composed of a vertical element added to both ends of the horizontal element. The horizontal stripes of the second element are arranged close to each other along the horizontal stripes of the first element, and the inner conductor of the coaxial cable is connected to the first element, and the outer conductor is connected to the second element. A glass antenna, characterized by being connected to a glass antenna. 2. The method according to claim 1, further comprising adding V to the horizontal line of the first element.
The glass antenna according to claim 1, wherein a central portion of the U-shaped element or the U-shaped element is connected to a feeding point of the first element.