JPH0630406B2 - Mobile device mounting antenna device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention has a plurality of element antennas arranged in a small size,
In addition, the present invention relates to a moving body mounting antenna device capable of switching the direction of a radiation beam in a plurality of directions.

[Conventional technology]

Conventionally, this type of mobile unit mounting antenna device is known as a train antenna device used for train radio, for example. FIG. 4 is a schematic configuration diagram showing a conventional antenna device. As shown in the figure, four unit antennas 1, 2, 3 and 4 are arranged side by side on the upper surface (horizontal surface) of a train roof (not shown), and the antenna device 5 is configured as a whole. Each unit antenna 1 to 4 is an antenna having a Yagi antenna configuration in which a monopole antenna is an element antenna, and each unit antenna 1 to 4 partially shares a reflector element (not shown) that is a Yagi antenna configuration element. It consists of four antennas that are almost independent of each other. The unit antennas 1 to 4 are respectively provided with input / output terminals 1a, 2a, 3a and 4a. A power supply circuit for inputting / outputting electric power to / from the antenna device 5 is provided with a switch (not shown) so as to selectively switch the input / output terminals 1a to 4a. The directions of the radiation beams of the unit antennas 1 to 4 are forward, backward, leftward, and rightward, as indicated by arrows in FIG. Therefore, each unit antenna 1 to 4 is selectively switched by the above-mentioned unit (not shown).
The direction of the radiation beam of the antenna device 5 can be switched to the forward direction, the backward direction, and the left-right direction. However, in the left direction and the right direction, in operation, since the radiation beams are emitted simultaneously in the left and right directions, the pumping power is always applied to the input / output terminals 3a and 4a at the same time. That is, as the radiation beam of the antenna device 5,
It can be switched to three directions, backward and leftward.

[Problems to be Solved by the Invention] In the above-described conventional mobile device mounting antenna device, each of the unit antennas is an antenna having a Yagi antenna structure, and thus the overall occupied area of the antenna device is large and heavy. There was a problem.

The present invention has been made to solve the above problems, and is lightweight by configuring an antenna device with a plurality of capacitor antennas holding a conductor plate with a dielectric,
It is an object to obtain an efficient antenna device for mounting on a moving body.

[Means for Solving the Problems] A movable body mounting antenna device according to the present invention includes a dielectric body attached to a ground conductor plate and holding the conductor plate, and a coaxial connector seat attached to the ground conductor plate. The inner conductor of the coaxial connector is penetrated through the inside of the dielectric and connected to the conductor plate.

[Operation] In the mobile object mounting antenna device of the present invention, the dielectric member holds the conductor plate and protects and insulates the inner conductor of the coaxial connector, thereby reducing the weight of the mobile object mounting antenna device. And efficiency can be improved.

〔Example〕

FIG. 1 is a schematic configuration diagram showing an antenna device according to an embodiment of the present invention. As shown in the figure, 6 element antennas
61,62,63,64,65,66 are arrayed in the form of 3 rows and 2 columns on a horizontal plane such as a roof of a train, and form an array antenna (2 × 3 element array antenna) as a whole. Make up 7. The arrangement intervals d ₁ and d ₂ of the element antennas 61 to 66 are determined from the antenna characteristics required for each radiation beam (forward direction, backward direction, and left-right direction), the beam width, and the front-back ratio of the radiation pattern. In the case shown in FIG. 1, the interval is
d ₁ λ / 2 and d ₂ λ / 3. However, λ is a wavelength.

FIG. 2 is a schematic cross-sectional configuration diagram showing each element antenna used in the antenna device of FIG. 2 as shown
A ground conductor plate 10 is provided on the back surface of a dielectric flat substrate, which is a so-called honeycomb substrate, having a core 9 sandwiched between a plurality of dielectric skins 8, while a circular radiation conductor plate 11 is provided on the front surface.
Are provided by etching or the like. Also,
12 is a coaxial plug seat, and this coaxial plug seat 12 is a ground conductor plate 10
The inner conductor 13 of the coaxial connector 12 extends through the core 9 of the honeycomb substrate, and its end is connected to the radiation conductor plate 11. The element antenna as shown in FIG. 2 is an antenna called a capacitor antenna, which has a radiation characteristic that is almost omnidirectional in a horizontal plane when the direction of the inner conductor 13 is considered as a vertical axis.

FIG. 3 is a schematic configuration diagram showing a feeding circuit used in the antenna device of FIG. In the figure, SW1 to SW12
Are single-pole double-throw switches, each of which uses a coaxial switch mechanically operated by voltage control. P1
P6 is a fixed phase shifter, and each uses a coaxial cable having a different length. Reference numeral 14 is a two-way distributor, 15 is a three-way distributor, 16 is an input / output terminal, 61 to 66 are element antennas similar to those in FIG. 1, and A and B are terminals. When the arrangement intervals of the element antennas 61 to 66 are determined as shown in FIG. 1, the excitation phase amount to be given to the element antennas 61 to 66 shown in FIG. 3 to form each radiation beam is determined. Therefore, the amount of phase change required for each of the fixed phase shifters P1 to P6 is easily determined from this required excitation phase amount. That is, the coaxial cable length of each of the fixed phase shifters P1 to P6 is determined. In the power supply circuit shown in FIG. 3, each switch S
W1 and SW2, SW3 and SW4, and SW5 and SW6 are
In either case, switching to terminals A and B switches to a phase difference of 0 ° and 180 °. In addition, the switches SW7 and SW8 have a phase difference of −120 ° and 120 °, and the switches SW9 and SW8 have a phase difference of
The phase difference between 0 and −120 ° can be switched with 10 and the phase difference between 120 ° and −120 ° can be switched with each switch SW11 and SW12.

Since the antenna device 7 of the present invention has the above-mentioned configuration, the direction of the radiation beam can be changed by appropriately selecting the combination of switching the terminals A and B by switching the connections of the switches SW1 to SW12. , As shown in FIG. 1, it is possible to switch to the forward direction, the backward direction, or the left-right direction. For example, all the switching terminals of the switches SW1 to SW6 are set to the terminal A side, and then the switches SW7 to S
If all the terminals of W12 are on the terminal A side, a forward radiation beam can be formed, and each switch SW7 and SW8 is at terminal B, and each switch SW9 and SW10 is at terminal A.
Further, by switching the switches SW11 and SW12 to the terminal B, respectively, a backward radiation beam can be formed. Further, all the switches SW1 to SW6 are switched to the terminal B side, and the switches SW7 and SW8 are connected to the terminal A.
Further, by switching the switches SW9 and SW10 to the terminal B and switching the switches SW11 and SW12 to the terminal B, a radiation beam in the left-right direction can be formed.

As is clear from the above description, in the six element antennas 61 to 66 shown in FIG. 1, all the element antennas 61 to 66 always operate effectively in any state. Further, the antenna device 7 shown in FIG. 1 has the same gain and beam width conditions required for each radiation beam when compared with the conventional antenna device 5 shown in FIG. The antenna aperture area of the antenna device 7 corresponds to only one of the unit antennas 1 to 4 shown in FIG. 4, and it is clear that the antenna occupying area is basically 1/100 of that of the conventional device. Become 4. Even if the antenna device 5 shown in FIG. 4 shares a passive reflector element (not shown) among the unit antennas 1 to 4, the antenna occupation of the antenna device 7 shown in FIG. 1 is occupied. The area is about half that of conventional equipment.

In the above embodiments, the switches SW1 to SW12 are described as coaxial switches that mechanically operate under voltage control. However, for example, diode switches may be used as the electrical switches.

Further, in the above-mentioned embodiment, as the distributors such as the two-divider 14 and the three-divider 15, from the viewpoint of reduction of size and weight, a ratless circuit composed of a strip line formed on a printed circuit board, a branch line coupler. Alternatively, a so-called hybrid distribution circuit such as a Wilkinson distributor can be used, and a reactive distribution circuit such as a tee branch can be used instead of the hybrid distribution circuit.

Further, in the above embodiment, a dielectric radome may be provided above the array surface of the element antennas 61 to 66 at an appropriate interval from the array surface to protect the antenna device 7.

Further, in the above embodiment, as the element antennas 61 to 66, omnidirectional antennas in a horizontal plane such as a monopole antenna can be used when the height conditions are loose. Further, instead of the 2 × 3 element array antenna used in the above embodiment, the number of element antennas and the array shape can be changed according to required conditions such as required gain and beam width.

[Advantages of the Invention] The invention holds a conductor plate by a dielectric and protects and insulates the inner conductor of the coaxial connector so that the inner conductor of the coaxial connector is not exposed to the outside. Connected, lightweight,
The effect is that the insulation of the inner conductor is ensured, the damage to the inner conductor is small, and the efficient antenna device for mounting on a moving body is obtained.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an antenna device according to an embodiment of the present invention, FIG. 2 is a schematic sectional configuration diagram showing each element antenna used in the antenna device of FIG. 1, and FIG.
1 is a schematic configuration diagram showing a feeding circuit used in the antenna device of FIG. 1, and FIG. 4 is a schematic configuration diagram showing a conventional antenna device. In the figure, 7 ... Antenna device, 10 ... Ground conductor plate, 11
...... Radiation conductor plate, 12 ...... Coaxial connector, 13 ...... Inner conductor, 14
...... 2 distributors, 15 …… 3 distributors, 16 …… I / O terminals, 61
〜66 …… Element antenna, SW1 ～ SW12 …… Switch,
P1 to P6 ... Fixed phase shifters. In the drawings, the same reference numerals indicate the same or corresponding parts.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Masaru Numazaki 5-1-1, Ofuna, Kamakura-shi, Kanagawa Mitsubishi Electric Corporation Information & Electronics Laboratory (72) Inventor Takayoshi Furuno 325 Kamimachiya, Kamakura-shi, Kanagawa Mitsubishi Electric Kamakura Manufacturing Co., Ltd. (72) Inventor Yoshiyuki Chatani 325 Kamimachiya, Kamakura City, Kanagawa Prefecture Mitsubishi Electric Co., Ltd. Kamakura Manufacturing (56) Reference JP 61-171203 (JP, A) (JP, U)

Claims (1)

[Claims] 1. An antenna device comprising a plurality of element antennas arranged, wherein the element antenna comprises a ground conductor plate and a conductor plate provided in parallel with the ground conductor plate.
A feeding circuit for feeding power to each of the element antennas by using a capacitor antenna having substantially non-directional radiation characteristics in a plane parallel to the ground conductor plate and arranging a plurality of the conductor plates on the same plane. By providing a plurality of fixed phase shifters, switches and distributors, all of the element antennas are always operated, and the radiation beam is switched in a plurality of directions in a plane parallel to the ground conductor plate. An antenna device mounted on a body, comprising: a dielectric body that is attached to the ground conductor plate and holds the conductor plate; and a coaxial plug seat that is attached to the ground conductor plate. A movable body mounting antenna device, wherein a conductor penetrates through the inside of the dielectric and is connected to the conductor plate.