JPH0818320A - Glass antenna - Google Patents

Abstract

(57) [Abstract] [Purpose] It is suitable for receiving weak radio waves from GPS satellites, etc., and can also be used as an antenna for car phones, personal radios, and personal handy phones that are being put to practical use. It is intended to provide a glass antenna. The present invention is a glass antenna arranged on a window glass for a moving body, wherein a part of a circular, elliptical or polygonal shape is opened, and a straight line or a curved line is formed from each end toward the inside. The first element 3 in which the formed zigzag-shaped elements are connected to each other to form a closed shape
₁ and a second element 3 ₂ having a shape along the horizontal line or the first element, and a part of each of them is used as a first feeding point and a second feeding point. The inner conductor of the coaxial cable is characterized in that the outer conductor is connected to the second 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 a moving body such as an automobile, a ship or an airplane.
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 theft or 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]

SUMMARY OF THE INVENTION The present invention is a glass antenna arranged on a window glass for a moving body, wherein a circular, elliptical or polygonal shape is partially opened and each end is internally opened. A zigzag-shaped element formed by a straight line or a curved line toward each other and having a first closed element and a second element formed along a horizontal line or the first element At the same time, a part of each of them is used as a first feeding point and a second feeding point, and the inner conducting wire of the coaxial cable is connected to the first feeding point and the outer conducting wire is connected to the second feeding point. It is preferable that the length of the outer circumference of the first element excluding the zigzag-shaped portion is in the range of 0.65λ to 1.2λ when the wavelength of the received radio wave is λ.

Particularly, it is preferable to dispose the heating wire of the rear window glass for a vehicle in a lower margin portion or an upper margin portion.

[0006]

In order to receive right-handed circularly polarized radio waves transmitted from GPS satellites, etc., a part of a circular, elliptical or polygonal shape is opened and a straight line or a curved line is formed from each end toward the inside. The formed zigzag-shaped elements are connected to each other to form a closed shape, and the first element to which the inner conductor of the coaxial cable is connected and the horizontal wire or the first element are arranged along the first element. The second element, which is connected to the external conductor, works well,
Particularly, by opening a part of the first element and connecting a zigzag-shaped element to each end, the number and amplitude of the zigzag-shaped elements are changed to facilitate impedance adjustment and tuning, and enhance the reception gain. To work.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below 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, and FIGS. 2 to 5 are main part details showing an antenna portion of the first to fourth embodiments of the present invention, respectively. FIG. 6 and FIG. 6 are directional characteristic diagrams of the antenna in the first embodiment (the front and the rear represent the direction of the automobile).

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 2, a heating wire 2 for anti-fog and anti-fog are provided on the inner side of the plate glass 1 for anti-fog. In the lower margin of the heating wire for use, a zigzag-shaped element formed by opening a part of an ellipse and forming a straight line from each end toward the inside is connected to form a closed shape. Element 3 of 1
The antenna 3 of the present invention composed of the second element formed by ₁ and the wide horizontal filament 3 ₂ is connected to the first feeding point 4
₁ (the second feeding point 4 ₂ is the end of the second element 3 ₂ ), along with another antenna 5 for receiving another FM radio broadcast wave etc. provided in the upper margin of the heating wire for anti-fog It is formed by screen-printing and firing with a conductive paste on the lower margin.

After mounting such a plate glass as a rear window glass, the inner conductor of the coaxial cable is connected to the feeding point 4 ₁ of the first element 3 ₁ and the second element 3 ₂ is connected.
An external conductor of a coaxial cable is connected to the feeding point 4 ₂ of.

Of the glass antenna thus obtained
The size of each part is the first element 3 ₁Oval outer circumference
The length of the part is 190mm, and the two zigzag straight lines
Each length is 30mm, total outer circumference length is 250mm,
Second element 3₂Horizontal length of 40mm, width of 3m
Depending on the value of m, 1.575 GHz (λ is about 19
Measurement of directional characteristics when receiving 0 mm right-hand circularly polarized wave
Then, when the cross dipole antenna is set to 0 dB
In terms of relative ratio, the directional pattern shown in FIG. 6 (the average reception gain is
-12.3 dB) was obtained, commercially available and put to practical use
The microstrip antenna is
The average is about -10 dB,
Good results almost equivalent to those of the cross-trip antenna were obtained.
It was confirmed that it could be put to practical use.

Embodiment 2 to Embodiment 5 In Embodiment 2 shown in FIG. 3, a first element 3 ₁ is formed by a straight line which is formed by opening a part of a circular shape and inward from each end. Connect two zigzag shaped elements, and open the second element 3 ₂ part of the circular shape,
This is an example including a zigzag-shaped portion arranged along the zigzag-shaped portion of the first element, wherein the outer circumference length of a part of the circle of the first element 3 ₁ is 130 mm, and the zigzag-shaped portion is 30 mm, respectively. It is formed by a straight line of 20 mm, the total length is 230 mm, the outer peripheral part of a part of the circle of the second element is 50 mm, the respective zigzag-shaped linear parts are 25 mm, 15 mm, and the total length is 130 mm. In Example 3 shown in FIG. 4, a part of the elliptical shape is opened, the zigzag shape is formed in a concave shape, the length of the outer peripheral part of the ellipse is 170 mm, and the linear length of the zigzag shape is the feeding point 4. _The horizontal part to which ₁ is connected is 20 mm, and the straight length from the horizontal part to both outsides is 10 m.
m, 20 mm, 20 mm, total length 290 mm, second
Elements 3 ₂ horizontal length of those 40 mm, a width 3 mm, the first element 3 Example 4 shown in FIG. 5 ₁
Is an example in which a part of the rectangular shape is opened, one zigzag-shaped element is connected, and the second element 3 ₂ is arranged along the first element. A part of a rectangle of 30 mm is opened, and zigzag-shaped parts are formed by straight lines of 25 mm, the total length is 240 mm, and the total length of the second element 3 ₂ is 7 mm.
It is 0 mm.

With such an antenna, 1.575
When the reception gain when receiving the right-hand circularly polarized wave of GHz was measured, good results were obtained in Example 2 and Example 4 which were slightly higher than Example 1, and Example 3 was almost the same as Example 1. Results were obtained.

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

The shape of the first element may be a pentagonal or more polygonal shape other than that of the embodiment, and the zigzag-shaped element is not limited to one formed by a straight line, but is a curved line sign. It may be formed in a curved shape.

Regarding the second element, the first embodiment,
It is preferable to use horizontal stripes as shown in the third embodiment and those arranged along the first element as shown in the second and fourth embodiments. There are advantages.

Although the auxiliary elements are not shown in Examples 1 to 4, the first and second elements are linear and L-shaped for the purpose of capacitive coupling with the heating wire and adjustment of impedance. Shaped or U-shaped elements can be added.

The location of the antenna 3 may be provided not only in the center of the lower margin of the anti-fogging heating wire of the rear window glass of the vehicle but also in the side of the lower margin or in the upper margin. Further, it may be provided on the front window glass, the sunroof, or the like, or may be provided on windows of aircrafts, ships, etc. other than vehicles.

Regarding the conductive material forming the antenna, in addition to the printed line formed by screen-printing a conductive paste, a transparent conductive film such as a sputtered film may be used when it is formed wide as shown in the fourth embodiment. Can be used. 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.

[0019]

The glass antenna of the present invention facilitates impedance adjustment and tuning by combining the first element with a unique shape and combining it with the second element and at the same time receives weak radio waves from GPS satellites. It can be received at a practical level even if the direction is changed, and can be used as an antenna for car phones 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 detailed view of a main part showing only an antenna part according to the first embodiment of the present invention.

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

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

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

FIG. 6 is a directional characteristic diagram of the antenna according to the first embodiment (before,
The rest represents the direction of the car).

[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 of this invention 4 ₁ 1st feeding point 4 ₂ 2nd feeding point 5 Another antenna

Claims (3)

[Claims] 1. A glass antenna arranged on a window glass for a moving body, which is formed by a straight line or a curved line from each end toward the inside by opening a part of a circular, elliptical or polygonal shape. A zigzag-shaped element is connected to form a first closed element, and a second element having a horizontal line or a shape along the first element is provided. And a second feeding point, wherein the inner conducting wire of the coaxial cable is connected to the first feeding point and the outer conducting wire is connected to the second feeding point. 2. The length of the outer periphery of the first element excluding the zigzag-shaped portion, when the wavelength of the received radio wave is λ,
The glass antenna according to claim 1, wherein the glass antenna has a range of 0.65λ to 1.2λ. 3. The glass antenna according to claim 1, wherein the glass antenna is arranged in a lower margin portion or an upper margin portion of a heating wire of a rear window glass for a vehicle.