JPH06237109A - Glass antenna for automobile telephone system - Google Patents

Abstract

PURPOSE:To provide a glass antenna for an automatic telephone system having excellent performance similar to that of a conventional pattern simultaneously by decreasing the length of a ground pattern in a horizontal direction and locating a feeding point to a side of the pattern so as to easily install the glass antenna to a glass edge side. CONSTITUTION:The antenna is provided with a radiation pattern 3, a signal lead wire 5a used to interconnect the pattern 3 and the inner conductor 6a of a coaxial feeder 6 and extended in a direction of the radiation pattern 3 from a feeding point 7 provided on the position of a glass 2 close to the edge of the glass 2 and a balanced/unbalanced conversion element 5c surrounding the feeding point 7, extended over nearly the total length of the signal lead wire 5a at both sides. The antenna is provided with the antenna pattern having a shielding lead wire 5b connecting to the outer conductor 6b of the coaxial feeder 6 and a square shaped grounding pattern 4 connecting to the end of the shielding lead wire 5b onto the face of the glass.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a glass antenna for a car telephone which is attached to a glass surface such as a window glass of a car and which is used as a transmitting / receiving antenna in the UHF band for a car telephone.

[0002]

2. Description of the Related Art The applicant of the present invention uses a radiation pattern having a vertical length of about 1/4 wavelength on a glass surface and a vertical length of about 1/4 wavelength on the glass surface as shown in FIG. A glass antenna having a grounding pattern having a length in the left-right direction of about 1/4 to 3/4 wavelength, the grounding pattern having a hollow shape including an outer frame pattern and a central vertical pattern is disclosed in Japanese Patent Application No. 4-38628. No. specification.

[0003]

However, since the horizontal direction of the grounding pattern is large and the radiation pattern (feeding point) is located in the center of the grounding pattern, the glass antenna is placed on the side of the glass edge. When installing, there is a problem that it is difficult to bring the antenna closer to the side of the glass edge (that is, it is difficult to form a feeding point in the black ceramic provided on the glass edge).

The present invention has been made to solve such a problem, and its object is to reduce the length of the grounding pattern in the left-right direction and to locate the feeding point at the side of the pattern so that the glass edge. An object of the present invention is to provide a glass antenna for a car telephone which is easy to install on the side portion and at the same time has the same excellent performance as the conventional pattern.

[0005]

In order to solve the above-mentioned problems, a glass antenna for a mobile phone according to the present invention has a position close to an edge of glass for connecting a radiation pattern and an inner conductor of a coaxial feeder. A signal lead-out line extending from the feeding point provided in the direction toward the radiation pattern, and extending over substantially the entire length of the signal lead-out line on both sides of the signal lead-out line, and having a balanced-unbalanced conversion element, A shield lead wire for connecting to the outer conductor of the coaxial power supply line,
An antenna pattern having a V-shaped grounding pattern connected to the end of the shield lead wire is provided on the glass surface.

At this time, the ends of the shield lead wires are connected to each other, and the connection portions and the connection portions of the signal lead wires and the radiation pattern are three-dimensionally arranged so as not to contact each other. Set up.

[0007]

The glass antenna for an automobile telephone according to the present invention is
A shield leader is formed so as to surround the signal leader extending from the feeding point set to a place near the glass edge to the radiation pattern, and a square-shaped grounding pattern with a small left and right length is connected to the end of the shield leader. . Therefore, the glass antenna can be disposed close to the glass edge on the side of the glass.

Further, the leading end of the lead-out line in the open state is connected to the antenna side pattern. Therefore, the impedance of the leader line patterned on the glass can be lowered, and the loss in the leader line can be reduced.

Further, by forming the grounding pattern into a hollow shape (square shape), it is possible to reduce the temperature difference at the time of heating associated with the bending process, and the strain having a desired curvature can be obtained in the bending process similar to the conventional one. It is possible to make the window glass with less.

[0010]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is an explanatory view showing the installation place when the glass antenna for a car telephone according to the first embodiment of the present invention is viewed from the passenger compartment side, and FIG. 2 is a pattern diagram thereof, showing an example of its preferable dimensions.

A glass antenna for a car telephone (hereinafter, simply referred to as a glass antenna) 1 includes a radiation pattern 3, a ground pattern 4, and a lead-out line 5 attached to a window glass 2.

A feeding electrode 7a and a grounding electrode 7b, which form a feeding point 7 fixed to each of the patterns 3 and 4, have an inner conductor at the other end of the coaxial feeding line 6 whose one end is connected to a telephone (not shown). A core wire 6a and an outer conductor copper wire braid 6
b are connected by soldering or the like. The feeding point 7 is set within about 50 mm from the glass edge 10. In addition, 7c and 7d show the grounding points of the feeding electrode 7a and the grounding electrode 7b.

In FIG. 1, 8 is a conductive wire for heating for anti-fogging, and 9 is a bus bar for feeding the conductive wire for heating.

Although each pattern is formed below the heating conductive wire in this embodiment, it may be formed above the heating conductive wire.

Although only one glass antenna is described below the conductive wire 9 for heating, the glass antenna is installed at two of the four installation locations in the vertical and horizontal directions, and the antenna at these two locations provides a diversity reception system. Is preferably configured.

The pattern is, for example, fine silver particles,
A conductive wire or a conductive metal thin wire formed by screen-printing a conductive paste obtained by forming a low-melting glass powder or the like into a paste with an organic solvent on the window glass 2 and further firing it.
It is formed using an appropriate conductive member such as a conductive metal foil.

The grounding pattern 4 is formed of outer frame patterns 4a, 4b, 4c, and 4d each having a length of approximately λ / 4 (herein, λ represents a wavelength) in the upper, lower, left, and right directions. Character shape. The outer frame patterns 4a and 4b are parallel to the glass edge 10 of the window glass,
c, 4d and the radiation pattern 3 are formed perpendicular to the glass edge 10 of the glazing.

The vertical and horizontal lengths of the grounding pattern 4 are λ /
The value of 4 corresponds to λ / 4 at 900 MHz when the shortening rate of the antenna formed on the glass substrate is 0.6. In FIG. 2, 11 indicates a black ceramic edge.

The size of the grounding pattern 4 is 50 m in width.
m, length 35 mm, and each outer frame pattern 4a, 4b, 4
The line width of c and 4d is 5 mm. The radiation pattern 3 has a line width of 4 mm and a length of 50 mm (about λ / 4), and has a hollow shape with a line width of 1 mm around the edges.

The lead-out line 5 comprises a signal lead-out pattern 5a which is a signal lead-out line and a shield pattern 5b which is a shield lead-out line, and is formed parallel to the glass edge 10.

The signal lead-out pattern 5a further extends 18 mm downward from the lower end of the radiation pattern 3 formed perpendicularly to the glass edge 10, and then the tip side thereof is parallel to the glass edge 10 and leftward. It is bent and extended by 50 mm and is connected to the power supply electrode 7a.

The power supply electrode 7a is provided on the outer frame patterns 4c to 5c.
It is formed at a position of 8 mm and has a square shape with a width of 8 mm and a length of 8 mm. The distance from the center line of the glass to the center of the power supply electrode 7a is 500 mm.

Signal extraction pattern 5a and outer frame pattern 4
The distance from c is 2 mm. The shield pattern 5b extends from the middle portion of the outer frame pattern 4c in parallel to the left along the glass edge 10 and beyond the power supply electrode 7a, and then bends the tip end side thereof perpendicularly to the glass edge 10 for further signal extraction. The open end is extended to the vicinity of the radiation pattern 3 by bending rightward in parallel so as to surround the power supply electrode 7a along the power supply pattern 5a.

The shield pattern 5b has a line width of 5 mm, the distance from the signal lead-out pattern 5a is 2 mm, and the distance from the power supply electrode 7a is 2 m at the upper and side portions, respectively.
m.

The distance between the open end of the shield pattern 5b and the signal extraction pattern 5a (radiation pattern 3) is 2 mm.

At this time, the signal lead-out pattern 5 is provided between the open end portion of the tip of the shield pattern 5b extending to the vicinity of the radiation pattern 3 and the outer frame pattern 4c of the ground pattern 4.
By arranging in a three-dimensional manner across a and short-circuiting, the impedance of the lead-out line is lowered, the loss in the lead-out line can be reduced, and a more preferable antenna pattern can be obtained.

The pattern 5c branched from the middle portion of the shield pattern 5b is a balanced / unbalanced conversion element having a length of about λ / 4, which is called a spell top element. Increase the impedance at the connection point to prevent current from flowing to the lead-out line (ground) side. The pattern line width is 3 mm, the length is 43 mm, and the interval with the shield pattern 5b is 4 mm. This spell top element may be omitted depending on the conditions.

When the window glass 2 is a laminated glass, the glass antenna is attached to the joint surface, the inside or outside surface of the vehicle, and when the window glass 2 is a single plate glass, it is attached to the inside or outside surface of the vehicle.

FIG. 3 is a graph showing frequency characteristics measured in a state where the glass antenna is mounted on an automobile to confirm the performance of the glass antenna. The horizontal axis represents frequency (unit: MHz),
The vertical axis represents the average gain (unit: dB) of the antenna. Also,
FIG. 4 shows the above graph as a numerical table.

(A) in the figure is a conventionally known NT.
The average gain of a pole antenna made by T (hereinafter referred to as NTT pole) is shown, and (b) shows side feeding (coaxial feeding line of 2.5D-2V is 7 in the antenna pattern of this embodiment).
The average gain when 0 cm is added is shown. here,
GRAY indicates a transmitting / receiving antenna among the diversity antennas.

When the standard 0 dB is used as the standard dipole antenna, it can be seen that the decrease in gain is only about 1.3 dB in the entire band of 790 to 970 MHz, compared with the NTT pole having a good average gain.

FIG. 5 is a block diagram of a glass antenna for an automobile telephone according to a second embodiment of the present invention, in which the same parts as those in FIG. This example shows a case where the glass is applied to a glass having a rounded glass edge, and an example of preferable dimensions thereof is shown.

In FIG. 5, the coaxial feed line 6 is provided at a position relatively distant from the patterns 3 and 4 so that the patterns 3 and 4 are not hidden by the coaxial feed line 6. Actually, the inner conductor of the other end of the coaxial power supply line 6 whose one end is connected to a telephone (not shown) for the power supply electrode 7a and the ground electrode 7b which form the power supply point 7 fixed to each pattern 3 and 4 And the copper wire braid 6b, which is an outer conductor, are connected at the shortest distance.

Also in this embodiment, the grounding pattern 4 has a hollow (square-shaped) shape composed of the outer frame patterns 4a, 4b, 4c and 4d each having a length of approximately λ / 4 in the upper, lower, left and right directions. is there. The outer frame patterns 4a and 4b are parallel to the glass edge 10 of the window glass, and the outer frame patterns 4c and 4b.
d and the radiation pattern 3 are the glass edges 1 of the window glass.
Form perpendicular to 0.

The grounding pattern 4 is formed from the center line CL to 6
The outer frame pattern 4d is formed at a position of 30 mm. The size is 40 mm in width and 50 mm in length, and each outer frame pattern 4
The line width of a, 4b, 4c and 4d is 5 mm. The radiation pattern 3 has a line width of 4 mm and a length of 50 mm.

The lead-out line 5 comprises a signal lead-out pattern 5a which is a signal lead-out line and a shield pattern 5b which is a shield lead-out line.

The signal extraction pattern 5a further extends downward by 13 mm continuously from the lower end of the radiation pattern 3 formed perpendicularly to the glass edge 10, and then the tip side thereof is bent upward in parallel with the glass edge 10. 41.5m
It is extended by m and connected to the power supply electrode 7a.

The power supply electrodes 7a are provided on the outer frame patterns 4c to 8c.
It is formed at a position of 5 mm and has a square shape with a width of 11 mm and a length of 11 mm. The feeding point 7 is set within 50 mm from the glass edge 10.

The distance between the signal extraction pattern 5a and the outer frame pattern 4c is 1.5 mm. The shield pattern 5b extends upward from the middle portion of the outer frame pattern 4c along the glass edge 10, in other words, in parallel with and along the signal extraction pattern 5a and beyond the power supply electrode 7a, and the tip side thereof is made into the glass edge 10. It is bent vertically and then bent downward in parallel along the signal extraction pattern 5a so as to surround the power supply electrode 7a, and the open end is extended to the vicinity of the radiation pattern 3.

The shield pattern 5b has a line width of 5 mm, the distance from the signal lead-out pattern 5a is 1.5 mm, the distance from the power supply electrode 7a is 10.5 mm at the upper portion, and the other is 1.5 mm.

Further, the open end and the signal lead-out pattern 5a
The distance from (radiation pattern 3) is 1.5 mm. The above-mentioned feeding electrode 7 is provided in the middle upper part of the portion of the shield pattern 5b which is bent perpendicularly to the glass edge 10.
A grounding electrode 7b forming the feeding point 7 is formed together with a.

The size of the ground electrode 7b is 11 mm in width and 14 mm in length. The electrodes 7a and 7b are formed to be larger than the lead-out line by connecting a connector (not shown) for a coaxial power feed line to this portion and using this to connect to the coaxial power feed line. Because there is.

In this embodiment, signal extraction is performed between the open end portion of the tip of the shield pattern 5b extending to the vicinity of the radiation pattern 3 and the outer frame pattern 4c of the ground pattern 4 (between AB in the figure). The glass edge 10 is three-dimensionally straddled over the pattern 5a, for example, by the jumper wire 11.
Connect in parallel with. A vinyl coated wire is used as the jumper wire 11 and is fixed to each pattern by soldering.

The jumper wire is not limited to the wire material such as the vinyl-coated wire, but may be a flat plate, for example, so that the open end of the shield pattern 5b and the ground pattern 4 do not come into contact with each other. Anything that can be arranged may be used.

The patterns 5c and 5d branched from the middle portion of the shield pattern 5b are spell top elements. The line width of the spell top element 5c is 3 mm, the length is 40 mm, and the distance from the shield pattern 5b is 5 mm.
Is. The line width of the spell top element 5d is 3 m.
m, the length is 40 mm, and the distance from the shield pattern 5b is 5 mm.

FIG. 6 is a graph showing the antenna characteristics measured in a state where the glass antenna is mounted on an automobile to confirm the performance of the glass antenna. The horizontal axis represents frequency (unit: MHz), and the vertical axis represents average gain (unit: unit) of the antenna. dB) is shown. Further, FIG. 7 shows the above graph as a numerical table.

(A) in the figure is a conventionally known 90.
The average gain of the antenna consisting of the radiation pattern for 0 MHz band and the pattern for grounding (the extraction line is removed from the antenna pattern of the above-mentioned embodiment) is shown, (b) is side feeding in the antenna pattern of this embodiment, The average gain of the antenna when there is no jumper wire, and (c) shows the average gain when side feeding is performed and a jumper wire is attached in the antenna pattern of this embodiment.

Assuming that the reference 0 dB is the standard dipole antenna, the gain reduction is about 1.3 dB without the jumper wire in the entire band of 790 to 970 MHz, whereas the gain reduction is 0. It can be seen that it has stopped at about 4 dB.

8 to 11 show 800 MHz, 850 MH
The directional characteristic figure at the time of mounting the glass antenna for car telephones in z, 900MHz, and 950MHz in a car, and measuring about V polarization is shown.

From the above measurement results, it can be seen that the glass antenna having the antenna pattern of this embodiment can obtain an antenna gain having sufficient practical performance despite the side feeding.

FIG. 12 is a structural diagram when the antenna pattern of the glass antenna for an automobile telephone according to the second embodiment of the present invention is modified and constructed.

This modified example has the same pattern as that of the above embodiment except that the pattern connected by jumper wires is changed. The same parts are designated by the same reference numerals and the description thereof will be omitted.

That is, this pattern is formed by newly forming a pattern between the grounding pattern and the shield pattern, which are connected by the jumper wire in the second embodiment, while the radiation pattern is connected by the pattern until now. And a signal extraction pattern are short-circuited (between CDs in the figure) by a jumper wire.

It should be noted that the radiation pattern may be provided at an angle, not perpendicular to the glass edge as shown in FIG. The preferred dimensions at this time are as shown.

The radiation pattern is not limited to the shape described above, and for example, the pattern width may be thickened to about 5 mm, the pattern may be formed by a plurality of thin lines, or T may be formed.
The shape may be changed to a V shape, an inverted L shape, or the like.

[0056]

As described above, according to the glass antenna for a car telephone according to the present invention, the signal lead wire extending from the feeding point to the radiation pattern is surrounded by the shield lead wire, and the end portion of the shield lead wire is further surrounded. Connect the square-shaped grounding pattern with a short left-right direction to. Therefore, the glass antenna can be arranged close to the side glass edge of the window glass. Therefore, power can be supplied from the side edge of the glass, and the power supply part can be hidden by the interior material, which is aesthetically pleasing.

Further, by connecting the tip end of the lead-out line which is in an open state to the antenna side pattern by a jumper wire, the impedance of the lead-out line patterned on the glass can be lowered and the loss in the lead-out line can be reduced. Therefore, it is possible to provide a good-quality ground with low ground resistance, and it is possible to obtain sufficient performance even in the case of side power feeding.

Furthermore, since the grounding pattern has a hollow shape (square shape), it is possible to reduce the temperature difference at the time of heating associated with the bending process, and the strain having a desired curvature can be obtained in the bending process similar to the conventional one. Can be made with less window glass.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an installation place when a glass antenna for an automobile telephone according to a first embodiment of the present invention is viewed from a passenger compartment side.

FIG. 2 is a pattern diagram of a glass antenna for a mobile phone according to the first embodiment of the present invention.

FIG. 3 is a characteristic diagram (graph) showing antenna gain.

FIG. 4 is a numerical table showing antenna gain.

FIG. 5 is a pattern diagram of a glass antenna for a mobile phone according to a second embodiment of the present invention.

FIG. 6 is a characteristic diagram (graph) showing antenna gain.

FIG. 7 is a numerical table showing antenna gain.

FIG. 8 is a directional pattern diagram at 800 MHz.

FIG. 9 is a directional characteristic diagram at 850 MHz.

FIG. 10 is a directional characteristic diagram at 900 MHz.

FIG. 11 is a directional characteristic diagram at 950 MHz.

FIG. 12 is a modified example of an antenna pattern of a glass antenna for a car phone.

FIG. 13 is a modification of an antenna pattern of a glass antenna for a car phone.

FIG. 14 is a pattern diagram of a conventional glass antenna for a car phone.

[Explanation of symbols]

1 ... Glass antenna for car phone, 2 ... Window glass, 3 ...
Radiation pattern, 4 ... Grounding pattern, 4a, 4b, 4
c, 4d ... Outer frame pattern, 5 ... Lead line, 5a ... Signal lead pattern, 5b ... Shield pattern, 5c, 5d
... Super-top element, 6 ... Coaxial feeder, 6a ... Core wire (inner conductor), 6b ... Copper wire braid (outer conductor), 7 ... Feeding point, 7a ... Feeding electrode, 7b ... Grounding electrode, 8 ... Heating Conductive wire, 9 ... Power supply bus bar, 10 ... Glass edge, 11
…Jumper.

Claims (3)

[Claims] 1. A signal lead-out line for connecting the radiation pattern to an inner conductor of a coaxial power feed line, the signal lead line extending toward the radiation pattern from a power feed point provided in a position close to an edge of glass, and the power feed. A shield leader for connecting to the outer conductor of the coaxial feeder, and a mouth connected to the end of the shield leader, extending on both sides of the signal leader along substantially the entire length of the signal leader. A glass antenna for a car telephone, characterized in that an antenna pattern having a V-shaped grounding pattern is provided on a glass surface. 2. A signal lead-out line for connecting the radiation pattern and an inner conductor of a coaxial power feed line, the signal lead line extending toward the radiation pattern from a feeding point provided in a position close to an edge of glass, and the power feed. A shield lead-out line for connecting to the outer conductor of the coaxial feed line, which has a balanced-unbalanced conversion element and extends on both sides of the signal lead-out line on both sides of the signal lead-out line, and has a shield-leader A glass antenna for a car telephone, characterized in that an antenna pattern having a V-shaped grounding pattern connected to an end of a wire is provided on a glass surface. 3. The end portions of both of the shield lead wires are connected to each other, and the connection portions and the connection portions of the signal lead wires and the radiation pattern are arranged so as not to contact each other. The glass antenna for a car telephone according to claim 1 or 2, characterized in that: