JP2000216613A - Side window glass antenna for automobile telephone - Google Patents

Abstract

PROBLEM TO BE SOLVED: To fit the shape of a general side window glass plate, to make it difficult to disturb a visual field and also to prevent beauty appearance from being damaged by curving a main antenna conductor from the top end of a conductor for phase adjustment downward at prescribed degrees and extending it. SOLUTION: An antenna conductor consists of a main antenna conductor 4a and a conductor 4b for phase adjustment, and the conductor 4b is extended from a feeding point 3 almost horizontally. The conductor 4a is curved at the top end of the conductor 4b at prescribed degrees and is extended. An angle θmade between the conductors 4a and 4b preferably ranges between 70 and 140 deg. and more preferably ranges between 90 to 120 deg. from the viewpoint of sensitivity improvement. The capacitive coupling part 6b of a ground conductor 6 and a side of an automobile front side of a car body open edge 5 are adjacent and are subjected to capacitive coupling. The length of the part 6b of the conductor 6 is >=45 mm from the viewpoint of sensitivity improvement. It is preferably >=65 mm and more preferably >=75 mm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
00 MHz band (810-960 MHz) and 1.5 GHz band (1.429-1.501 GH) for car phones
z) for a side window glass antenna for a mobile phone.

[0002]

2. Description of the Related Art A window glass antenna for a mobile phone shown in FIG. 2 is conventionally known (JP-A-4-34791).
0). In FIG. 2, five antenna conductors 13 extending radially and a feed point 1
5 and an earth conductor 14 are provided, and a reception signal between the feeding point 15 and the earth conductor 14 is sent to the receiver.

[0003]

When an attempt is made to provide the glass antenna shown in FIG. 2 on a side window glass plate of an automobile, a portion provided along the opening edge of the vehicle body is small.
Therefore, it is not suitable for the shape of a general side window glass plate,
There is a problem that the visual field is easily obstructed and the beauty is impaired.
Also, the area of the ground conductor 14 is as large as 1320 mm ^2, and the shape of the ground conductor 14 is trapezoidal.
It was easy to obstruct the field of view and hurt the beauty.

[0004]

According to the present invention, an antenna conductor, a feeding point and a grounding conductor are provided on a side window glass plate of an automobile to solve such a problem. In the side window glass antenna for a car phone, a signal between the transmission signal or the reception signal,
The antenna conductor is composed of a main antenna conductor and a phase adjustment conductor, and the phase adjustment conductor extends in a substantially horizontal direction from the feeding point, and the main antenna conductor is bent downward at a predetermined angle from the tip of the phase adjustment conductor. The earth conductor and the vehicle body opening edge are capacitively coupled, and the length of the capacitive coupling portion of the ground conductor, which is capacitively coupled to the vehicle body opening edge, is 45 mm or more. Provide a side window glass antenna for a mobile phone.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the drawings. In the side window glass antenna for a mobile phone according to the present invention shown in FIG. 1, an antenna conductor 4, a feed point 3, and a ground conductor 6 are provided on a side window glass plate 1 of a vehicle. The received signal between the feeding point 3 and the ground conductor 6 is sent to a transceiver (not shown). At the time of transmission, a transmission signal is applied between the feeding point 3 and the ground conductor 6. Therefore, the side window glass antenna for a mobile phone of the present invention functions as a dipole antenna. When a coaxial cable (not shown) is used, the feed point 3 is connected to the inner conductor of the coaxial cable, and the feeder 6 a of the ground conductor 6 is connected to the outer conductor of the coaxial cable.

The antenna conductor comprises a main antenna conductor 4a and a phase adjusting conductor 4b, and the phase adjusting conductor 4b extends substantially horizontally from the feeding point 3. The main antenna conductor 4a is bent and extended at a predetermined angle from the tip of the phase adjusting conductor 4b. From the viewpoint of improving sensitivity, the angle θ between the main antenna conductor 4a and the phase adjustment conductor 4b is 70 to
140 ° is preferable, and 90 to 120 ° is more preferable.

The main antenna conductor 4a is connected to the phase adjusting conductor 4b via the bent portion 4c, and the bent portion 4c is usually of an acute angle, a right angle or an obtuse angle, but the bent portion 4c has a gentle circle. It may be arc-shaped. When the bent portion 4c has a gentle arc shape, the radius of this arc is preferably 30 mm or less, more preferably 10 mm or less, from the viewpoint of improving sensitivity.

The capacitive coupling portion 6b of the ground conductor 6 (the end of the ground conductor 6 on the front side of the vehicle) and the side of the vehicle body opening edge 5 on the front side of the vehicle are closely and capacitively coupled. The distance between the ground conductor 6 and the opening edge 5 of the vehicle body is preferably 0.2 to 30 mm in order to achieve good capacitive coupling and improve sensitivity.
0.2 to 15 mm is more preferable.

The length of the capacitive coupling portion 6b of the ground conductor 6 (the vertical length of the ground conductor 6 in FIG. 1) is 45 mm or more from the viewpoint of improving sensitivity. It is preferably at least 65 mm, more preferably at least 75 mm. The shape of the ground conductor 6 is a rectangle whose longitudinal direction is the vertical direction in FIG. It may be a letter shape or the like.

[0010] The area of the ground conductor is 500 to 2000 m.
m ² is preferred. 50 for 500 mm ² or more
Sensitivity is improved as compared with the case where it is less than 0 mm ² . 2
If it is 000 mm ² or less it is difficult to interfere with the field of view as compared with the case of the 2000 mm ² greater.

The vertical component length L of the main antenna conductor 4a is preferably 0.1 × λ _{M to} 0.4 × λ _M from the viewpoint of improving sensitivity. Here, λ _M is the wavelength of the center frequency in the 800 MHz band for car phones or the 1.5 GHz band for car phones. The reason why the length of the main antenna conductor 4a is determined only by the vertical component length L of the main antenna conductor 4a is that radio waves in the automobile telephone band mainly consist of vertically polarized waves.

The length of the phase adjusting conductor 4b is preferably in the range of 0.08 × λ _{M to} 0.36 × λ _M from the viewpoint of improving the sensitivity. The line width of the main antenna conductor 4a and the phase adjusting conductor 4b is preferably 2 mm or less, more preferably 0.2 to 1 mm, from the viewpoint of improving the visual field.

In a side window glass antenna for a mobile phone shown in FIG. 3, which is another embodiment different from that shown in FIG.
Book. In this manner, a plurality of antenna conductors 4 may be provided. As shown in FIG. 3, by changing the length of each antenna conductor 4, a wider band can be achieved.

The antenna conductor 4, the feeding point 3 and the ground conductor 6 are usually formed by printing a paste containing a conductive metal, such as a conductive silver paste, on the inner surface of the side window glass plate and printing it. Manufactured by
Not limited to such a forming method, a conductive linear body or foil-like body such as a copper wire may be formed on the inside or outside surface of the side window glass plate, or provided inside the side window glass plate. Is also good.

[0015]

EXAMPLES Examples (Examples 1 to 5) and Comparative Examples (Example 6) A side window glass antenna for a car telephone as shown in FIG. 1 was manufactured using a right rear side window glass plate of an automobile. Table 1 shows the dimensions (unit: mm) of each part and the value of the angle θ. However, the vertical dimension of the ground conductor 6 (the length of the capacitive coupling portion 6b) is 90 mm (Example 1) and 80 m.
m (Example 2), 70 mm (Example 3), 60 mm (Example 4), 5
0 mm (Example 5) and 40 mm (Example 6). The frequency used was 850 MHz.

FIG. 4 shows the results of measuring the sensitivity at the time of receiving an automobile telephone for Examples 1 to 6. In addition, as a result of performing a car telephone transmission test in an anechoic chamber, Examples 1 to 5 could be transmitted satisfactorily, and Example 6 could not be transmitted satisfactorily.

[0017]

[Table 1]

[0018]

The side window glass antenna for a mobile phone according to the present invention is suitable for the shape of a general side window glass plate, hardly obstructs the field of view, and has little problem of deteriorating aesthetic appearance. Furthermore, it has excellent transmission / reception characteristics in communication in the 800 MHz band for car phones and in the 1.5 GHz band for car phones.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention.

FIG. 2 is a configuration diagram of a conventional example.

FIG. 3 is an enlarged configuration diagram of a main part of another embodiment of the present invention.

FIG. 4 is a graph showing sensitivity at the time of reception in Examples 1 to 6.

[Explanation of symbols]

 1: Rear side window glass plate 3: Feeding point 4: Antenna conductor 4a: Main antenna conductor 4b: Phase adjustment conductor 5: Body opening edge 6: Ground conductor 6a: Feeding portion of ground conductor 6 6b: Capacity of ground conductor 6 Coupling part

Claims (1)

[Claims] 1. A side window glass for an automobile telephone, wherein an antenna conductor, a feed point and a ground conductor are provided on a side window glass plate of a vehicle, and a signal between the feed point and the ground conductor is a transmission signal or a reception signal. In the antenna, the antenna conductor is composed of a main antenna conductor and a phase adjustment conductor, the phase adjustment conductor extends in a substantially horizontal direction from a feeding point, and the main antenna conductor is at a predetermined angle from the tip of the phase adjustment conductor. It is bent downward and extended, and the ground conductor and the vehicle body opening edge are capacitively coupled, and the capacitance coupling part of the ground conductor, which is capacitively coupled with the vehicle body opening edge, is 45 mm or more. Features a window glass antenna for car phones.