JPH0577781U - Anechoic chamber - Google Patents

Abstract

(57) [Summary] [Purpose] To enable measurement of stereoscopic directional characteristics by sending radio waves to the DUT from an arbitrary angle. [Structure] A base end of an arc-shaped guide rail 12 is rotatably supported on the floor surface of the recess 11, and a rod tip of a cylinder unit 14 is connected to the guide rail 12. The sub guide rail 19 is rotatably attached via the joint 18, and the cylinder unit 20 fixed to the guide rail 12 folds the sub guide rail 19. The guide rail 12 and the sub guide rail 19 are connected to the motor 21. The moving body 22 traveling along the rail is engaged, and the transmitting antenna 23 is attached to the moving body 22.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an anechoic chamber used for measuring the characteristics of a receiving antenna mounted on an automobile, an aircraft, etc., measuring unnecessary radio waves generated from electronic devices mounted on automobiles, or measuring the influence of external interference waves on electronic devices.

[0002]

[Prior Art]

 A general radio wave measuring device is an open site type that has a transmitting antenna and an object to be measured such as a car installed outdoors, but this type has poor reproducibility of measurement, and is disturbed by external noise, and even in a location. The conditions are very limited. For this reason, an anechoic chamber is built in which the side walls, ceiling and floor of the building are covered with an electromagnetic wave absorber.

Initially, the shape of the anechoic chamber was a rectangular parallelepiped, but recently, one end of the chamber has a narrow transmitting portion and the other end has a wide receiving portion on which an object to be measured is set. A taper-type anechoic chamber has been developed in which a taper-shaped waveguide is connected to allow a large distance between the transmitter and the receiver.

[0004]

[Problems to be solved by the device]

 In the conventional anechoic chamber described above, the positional relationship between the receiving antenna and the DUT is fixed, and the stereoscopic directional characteristics such as the receiving characteristics of radio waves transmitted from communication satellites and the receiving characteristics from multiple transmitting antennas are fixed. Alternatively, it is not possible to accurately measure the data regarding the reception characteristics when the transmission antenna moves.

[0005]

[Means for Solving the Problems]

 In order to solve the above-mentioned problems, the present invention forms an outward recess in a part of the side wall of an anechoic chamber, and rotates the base end of an arc-shaped guide rail for measuring stereoscopic directional characteristics in this recess. It is movably supported, and a transmitting antenna is movably attached to the guide rail.

[0006]

[Action]

 By driving the cylinder unit etc. and rotating the guide rail downward from the state of standing up about the base end part, and further moving the transmitting antenna to the tip of the guide rail, the transmitting antenna is positioned above the object to be measured. Will be located in. Also, when transmission is not performed from above or diagonally above, the guide rail is rotated upward and stored in the recess together with the antenna.

[0007]

【Example】

 Embodiments of the present invention will be described below with reference to the accompanying drawings. Here, FIG. 1 is an overall plan view of an anechoic chamber according to the present invention, FIG. 2 is an enlarged view of FIG. 1 seen from the AA direction, and FIG. 3 is an enlarged view of the guide rail tip portion. A tapered anechoic chamber is shown.

In the anechoic chamber, one end of the building 1 is a narrow transmission part 2 and the other end is an enlarged reception part 3. The transmission part 2 and the reception part 3 are gradually expanded toward the reception part 3. It is continuous with a tapered waveguide section 4, a transmitting antenna 5 is fixed to the transmitting section 2, a turntable 6 is provided on the floor of the receiving section 3, and an object to be measured W such as an automobile is placed on the turntable 6. It is placed.

The side walls, ceiling, floor and back wall of the transmitter 2 and the receiver 3 are covered with a radio wave absorber 7. The radio wave absorber 7 is constructed by attaching a wedge-shaped carbon-containing foam 7b to the surface of a thin plate-shaped ferrite absorber 7a. Further, the electromagnetic wave absorber 7 is continuously attached to the side wall, the ceiling, and the floor of the waveguide unit 4 near the transmitting unit 2 and the receiving unit 3, and the floor surface of the waveguide unit 4 is made of ferrite and conductive material. It is a ground equivalent floor 8 that combines films.

An opening 9 for loading and unloading the object to be measured W is provided on one side wall of the receiving section 3, and the opening 9 is opened and closed by a partition-shaped radio wave absorber 10, and the other side wall is provided. A recess 11 is formed, and the recess 11 is opened / closed by a partition-shaped electromagnetic wave absorber 10, and a mechanism for measuring a stereoscopic directional characteristic is provided inside.

That is, a base end of an arc-shaped guide rail 12 is rotatably supported on the floor surface of the recess 11, and a cylinder pivotally supported on the upper end of a column 13 standing on the floor surface. The rod tip of the unit 14 is connected to the back side of the guide rail 12, one end of the wire 15 is fixed to the middle portion of the guide rail 12, and the wire 15 is attached to the side wall of the building 1 via a pulley 16. It hangs downward and a balance weight 17 is attached to its lower end.

Further, a sub guide rail 19 is rotatably attached to a portion of the guide rail 12 beyond the wire fastening portion via a joint 18, and the sub guide is fixed by a cylinder unit 20 fixed to the guide rail 12. The rail 19 has a structure of folding, and the sub-guide rail 19 forms an arc continuously with the tip of the guide rail 12 in a state where the cylinder unit 20 is extended.

Further, the guide rail 12 and the sub-guide rail 19 are engaged with a moving body 22 that travels along the rail by a motor 21, a transmitting antenna 23 is attached to the moving body 22, and the transmitting antenna 23 is attached. Is rotated by a motor 24. In FIG. 1, 25 is a measuring room, and 26 is a staircase.

In the above, for example, in order to measure the characteristics of the receiving antenna provided on the object to be measured W, the partition-shaped electromagnetic wave absorber 10 is removed as shown in FIG. 2, and the cylinder unit 14 is extended. The guide rail 12 is rotated toward the center of the receiver 3 by a predetermined angle. At this time, the cylinder unit 20 is also extended, and the sub-guide rail 19 and the guide rail 12 integrally form a continuous arc. Further, since the balance weight 17 is provided when the guide rail 12 vertically rotates (swings), the driving force of the cylinder unit 14 can be small.

Then, in the state where the sub guide rail 19 and the guide rail 12 are continuous as described above, the motor 21 is driven to move the moving body 22 equipped with the transmitting antenna 23 to an arbitrary position on the sub guide rail 19 or the guide rail 12. After traveling to the position and fixing at a predetermined position, radio waves are emitted toward the DUT W and the reception characteristic data of the DUT W is measured.

On the other hand, if the guide rails 12 and the like are left as they are in the receiving unit 3 after the measurement is completed, when measuring using the transmitting antenna 5 of the transmitting unit 2, the radio waves emitted from the transmitting antenna 5 are disturbed. Will be done. Therefore, in this case, first, the cylinder unit 20 is contracted and the sub guide rail 19 is folded, and then the cylinder unit 14 is further extended and lowered to the position shown by the imaginary line in FIG. 4, and the antenna 23 is removed in this state. .. Then, after that, the cylinder unit 14 is contracted and the guide rail 12 is erected up to the position shown by the solid line in FIG. 4, and all the mechanisms including the guide rail 12 for measuring the stereoscopic directional characteristics are housed in the recess 11 and the recess 11 is screened. The electromagnetic wave absorber 10 is closed.

Although a tapered anechoic chamber is shown in the illustrated example, the present invention can also be applied to a rectangular anechoic chamber.

[0018]

[Effect of the device]

 As described above, according to the present invention, an arc-shaped guide rail is provided in the anechoic chamber, and the transmitting antenna can be moved along this guide rail. It is possible to send radio waves from an angle to measure stereoscopic directional characteristics, and if combined with a separate transmitting antenna, it is also possible to measure multi-sources (multiple transmitting sources).

Furthermore, since the guide rail is rotatable and can be stored in the recess formed in the side wall of the anechoic chamber when it is not needed, it does not become an obstacle when performing measurement by using another transmitting antenna. If the rail can be folded in the middle, the depth of the recess can be reduced and the volume of the anechoic chamber can be reduced.

[Brief description of drawings]

FIG. 1 is an overall plan view of an anechoic chamber according to the present invention.

FIG. 2 is an enlarged view of FIG. 1 viewed from the AA direction.

[Fig. 3] Enlarged view of the tip of the guide rail

FIG. 4 is a diagram for explaining how the antenna is stored and how to replace it.
Similar figure to

[Explanation of symbols]

1 ... Building, 2 ... Transmitter, 3 ... Receiver, 4 ... Waveguide, 5,
23 ... Transmission antenna, 7, 10 ... Electromagnetic wave absorber, 11 ... Recess, 12 ... Guide rail, 18 ... Joint, 19 ... Sub guide rail, W ... DUT.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Harinori Murakami, 3-5-11 Doshumachi, Chuo-ku, Osaka City, Osaka Prefecture Nippon Sheet Glass Co., Ltd. (72) Keisuke Tanaka 3-chome, Doshomachi, Chuo-ku, Osaka City, Osaka Prefecture 5-11 No. 11 Nippon Sheet Glass Co., Ltd. (72) Ken Ken Ishino 1-13-1, Nihonbashi, Chuo-ku, Tokyo Inside TDC Corporation (72) Yasuo Hashimoto 1-1-13 Nihonbashi, Chuo-ku, Tokyo TDK Corporation

Claims (3)

[Scope of utility model registration request] 1. An anechoic chamber in which all or a major part of a side wall, a ceiling and a floor of a building on which an object to be measured is set is covered with an electromagnetic wave absorber. The base end of the arc-shaped guide rail is rotatably supported in the recess so that the tip of the guide rail can face above the object to be measured. An anechoic chamber characterized by a movable mount. 2. An anechoic chamber has one end that is a narrow transmitting section to which another transmitting antenna is fixed, and the other end that is a wide receiving section on which an object to be measured is set. The anechoic chamber according to claim 1, wherein is a tapered waveguide portion, and a recess for accommodating a guide rail is formed on a side wall of the receiving portion. 3. The anechoic chamber according to claim 1, wherein the guide rail is foldable at an intermediate portion.