JP2007258902A - In-vehicle dielectric antenna and adjustment method of antenna element thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an in-vehicle dielectric antenna that can avoid antenna element from becoming multiproduct, in advance, and enhancing the flexibility of an antenna assembly. <P>SOLUTION: A dielectric member 54 is removably assembled on a path of a GPS radio wave at the inside of a radome 6. An optimum antenna characteristic can be obtained in a state of antenna assembly, without the need for adjusting the antenna element 8 by adjusting the arranged position of the dielectric member 54 or changing its type of material. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a vehicle-mounted dielectric antenna in which a radome is assembled to a case so as to cover the radiation / arrival direction of radio waves as viewed from the antenna element, and an adjustment method for the antenna element.

A vehicle-mounted dielectric antenna incorporating a VICS (registered trademark) optical beacon is provided as one package of a plurality of antennas (see, for example, Patent Document 1).
JP 2000-33288 A

  By the way, in a dielectric antenna such as a GPS antenna, an antenna element (electrode) is adjusted so that optimum antenna characteristics can be obtained in an antenna assembly state, and the dielectric antenna adjusted with the antenna element is accommodated in a case, Was assembled to the case to make an antenna assembly.

  However, in the case of adjusting the antenna element so that optimum antenna characteristics can be obtained in the antenna assembly state, it is necessary to adjust the antenna element according to the size and shape of the antenna assembly every time a new antenna assembly is designed. Therefore, there is a problem that the antenna elements become a wide variety and the management and design are complicated. On the other hand, if the antenna element is not adjusted, there is a problem that the size and shape of the antenna assembly must be the same, and the design freedom of the antenna assembly is reduced.

  The present invention has been made in view of the above-described circumstances, and an object of the present invention is to avoid a variety of antenna elements, and to increase the degree of freedom in designing an antenna assembly. It is an object of the present invention to provide a vehicle-mounted dielectric antenna and a method for adjusting the antenna element.

  According to the in-vehicle dielectric antenna according to claim 1, the radome is assembled to the case so as to cover the radiation / arrival direction of the radio wave when viewed from the antenna element to be in the antenna assembly state. Since the dielectric member is detachably assembled on the radio wave path inside the antenna element, the antenna element can be adjusted by adjusting the position of the dielectric member (distance from the antenna element) or changing the material. It is possible to obtain optimum antenna characteristics in the antenna assembly state without having to adjust the frequency. As a result, it is not necessary to adjust the antenna elements each time a new antenna assembly is designed, and it is possible to avoid a large variety of antenna elements, and to increase the degree of freedom in designing the antenna assembly. be able to.

  According to the method for adjusting the antenna element of the in-vehicle dielectric antenna according to claim 2, the radome is assembled to the case so as to cover the radiation / arrival direction of the radio wave when viewed from the antenna element of the in-vehicle dielectric antenna. When the assembly state is set, the dielectric member is detachably assembled on the radio wave path inside the radome, and the radome with the dielectric member is assembled to the case so as to be in the antenna assembly state. In the same manner as described in the first aspect, it is possible to avoid a variety of antenna elements, and to increase the degree of design freedom of the antenna assembly.

  Hereinafter, an embodiment in which the present invention is applied to a vehicle-mounted integrated antenna in which a GPS antenna, a VICS radio beacon antenna, and a VICS optical beacon are packaged will be described with reference to the drawings.

The in-vehicle integrated antenna 1 includes a GPS antenna 3 (in-vehicle dielectric antenna in the present invention), a VICS radio beacon antenna 4 and a VICS optical beacon 5 housed in a case 2 whose upper side is open. A radome 6 is assembled to the case 2 so as to cover the beacon antenna 4 and the VICS optical beacon 5 from above.
The GPS antenna 3 is composed of a dielectric antenna in which an antenna element (electrode) 8 made of a metal plate material is mounted on the upper surface of a rectangular dielectric 7 made of resin, for example, and is mounted on the front surface 9a side of the main board 9. ing. In this case, since the arrival direction of the GPS radio wave radiated from the GPS satellite is the zenith direction, the vehicle is such that the element surface (electrode surface) 8a of the antenna element 8 faces the zenith direction when the in-vehicle integrated antenna 1 is in the antenna assembly state. Mounted on.

The VICS radio beacon antenna 4 is composed of a folded monopole antenna whose element 10 is bent and shaped in a low posture, and is mounted on the front surface 9a side of the main board 9 while being mechanically supported by a pedestal 11. ing. In this case, the pedestal 11 is fixed to the main board 9 by fitting two fitting parts 11 a and 11 b protruding downward into the fitting holes 9 c and 9 d of the main board 9.
The VICS optical beacon 5 is composed of three LEDs (light emitting diodes) 12 to 14 and one PD (photo diode) 15 (see FIG. 5), and has a predetermined angle with respect to the main board 9. It is mounted on the surface 16a side of the sub-board 16 that is inclined at. A connection connector 17 is mounted on the front surface 16a side of the sub-board 16, and a connection connector (not shown) is mounted on the back surface 9b side of the main board 9. A connection cable (not shown) is connected to these connection connectors. The main board 9 and the sub board 16 are electrically connected (conducted).

  Electronic circuits such as amplifiers, bandpass filters, and diplexers, which will be described later, are mounted on the back surface 9b side of the main substrate 9, and these electronic circuits are housed in a shield case 18 and insulated from the surroundings. The main board 9 is hooked and fixed to the claw portions 2a and 2b formed on the case 2, and the sub board 16 is hooked on the claw portions 2c and 2d formed on the case 2. Is fixed.

FIG. 5 shows an electric circuit diagram of the on-vehicle integrated antenna 1 described above. The in-vehicle integrated antenna 1 includes a power supply unit 21, a GPS antenna unit 22, a VICS radio beacon antenna unit 23, and a VICS optical beacon unit 24.
The power supply unit 21 is provided with a signal input / output terminal 27 for the GPS antenna unit 22 and the VICS radio wave beacon antenna unit 23 through a capacitor 26 from the power supply / signal input / output terminal 25, A signal input / output terminal 30 for the VICS optical beacon unit 24 is provided from the output terminal 25 through a strip line 28 and a capacitor 29.

  The power supply unit 21 is provided with a power supply terminal 32 for the VICS optical beacon unit 24 from the power supply / signal input / output terminal 25 through the strip line 28 and the coil 31, and the power supply / signal input / output terminal. A power terminal 36 for the first amplifier 34 and the second amplifier 35 is provided from 25 through a strip line 28, a coil 31 and a three-terminal regulator 33.

  In the GPS antenna unit 22, the GPS antenna 3 is connected to the signal input / output terminal 27 of the power supply unit 21 via a first amplifier 34, a bandpass filter 37, a second amplifier 35, a diplexer 38 and an attenuator 39. . In this case, the first amplifier 34 and the second amplifier 35 are supplied with operating power from the three-terminal regulator 33 via the power terminal 36. Further, in the VICS radio beacon antenna unit 23, the VICS radio beacon antenna 4 is connected to the signal input / output terminal 27 of the power source unit 21 via the diplexer 38 and the attenuator 39.

  In the VICS optical beacon unit 24, the three LEDs 12 to 14 and one PD 15 described above are connected to the connection connector 17 on the sub board 16 side and the connection connector 40 on the main board 9 side. Thus, the multi-synthesis circuit 42 is connected via the connection connector 17, the connection cable 41 and the connection connector 40. The multiple combining circuit 42 has a signal input / output terminal connected to the signal input / output terminal 30 of the power supply unit 21 and a power supply terminal connected to the power supply terminal 32 of the power supply unit 21.

  Now, as shown in FIG. 4, the radome 6 described above is integrally formed with hanging wall portions 51 and 52 so as to hang from the inclined ceiling inner wall portion 6a. 53d is integrally formed. The flat dielectric member 54 is located at a predetermined distance from the element surface 8a of the antenna element 8 of the GPS antenna 3 when the radome 6 is normally assembled to the case 2, and the entire upper side of the element surface 8a is disposed. So that the in-vehicle integrated antenna 1 is detachably hooked to the claws 53a to 53d on the path of the GPS radio wave when it is mounted on the vehicle in the antenna assembly state (the state shown in FIG. 3). Assembled.

  At this time, the antenna characteristics of the GPS antenna 3 are influenced by the dielectric member 54 when the dielectric member 54 is disposed on the GPS radio wave path. Further, desired antenna characteristics can be obtained by adjusting the arrangement position of the dielectric member 54 (distance from the antenna element 8) or changing the material. In addition, by adjusting the arrangement position of the dielectric member 54 or changing the material in this way, desired antenna characteristics can be obtained. However, by arranging the dielectric member 54, the resonance frequency of the antenna element 8 can be obtained. Therefore, it is necessary to set the resonance frequency of the original antenna element 8 higher than the desired frequency.

  In the above-described configuration, in order to enter the antenna assembly state, after the GPS antenna 3, the VICS radio beacon antenna 4 and the VICS optical beacon 5 are accommodated in the case 2, the dielectric member 54 is hooked on the claw portions 53a to 53d and the radome 6 is engaged. The radome 6 assembled with the dielectric member 54 is assembled to the case 2 so as to cover the GPS antenna 3, the VICS radio beacon antenna 4 and the VICS optical beacon 5 from the upper side, so that the antenna assembly state is obtained. it can.

  As described above, according to the present embodiment, the in-vehicle integrated antenna 1 is configured such that the dielectric member 54 is detachably assembled on the GPS radio wave path inside the radome 6. By adjusting the arrangement position or changing the material, it is possible to obtain optimum antenna characteristics in the antenna assembly state without the need to adjust the antenna element 8, which makes the antenna element 8 a wide variety. Can be avoided, and the degree of freedom in designing the antenna assembly can be increased.

The present invention is not limited to the above-described embodiment, and can be modified or expanded as follows.
The antenna accommodated in the case is not limited to a GPS antenna, a VICS radio beacon antenna, and a VICS optical beacon, but may be another antenna such as an ETC antenna, an XM antenna or a Sirius antenna for the North American market. Further, the number of antennas accommodated in the case is not limited to a plurality, and may be one.
The dielectric member is not limited to a flat plate shape, and may have another shape.

The perspective view which shows one Embodiment of this invention and shows the decomposed | disassembled aspect The perspective view which shows the aspect before a radome is assembled | attached to a case. The perspective view which shows the aspect after a radome is assembled | attached to the case. A perspective view showing a state in which the dielectric member is assembled to the radome, as seen from the back side of the radome. Electrical diagram

Explanation of symbols

  In the drawing, 2 is a case, 3 is a GPS antenna (vehicle-mounted dielectric antenna), 6 is a radome, 8 is an antenna element, and 54 is a dielectric member.

Claims (2)

A vehicle-mounted dielectric antenna in which a radome is assembled to a case so as to cover the radiation / arrival direction of radio waves when viewed from an antenna element, and is in an antenna assembly state,
An in-vehicle dielectric antenna, wherein a dielectric member is detachably assembled on a radio wave path inside the radome.   When the radome is assembled to the case so as to cover the radiation / arrival direction of the radio wave when viewed from the antenna element of the in-vehicle dielectric antenna, the dielectric member is attached to and detached from the radio wave path inside the radome. A method for adjusting an antenna element of a vehicle-mounted dielectric antenna, wherein the antenna assembly is assembled by attaching the radome to which the dielectric member is assembled to the case.

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