JPH04169865A - Radio wave dark room - Google Patents

Abstract

PURPOSE:To achieve a lowering of construction cost by switching a floor surface over to a non-reflection surface or a reflection surface to realize more than one radio wave dark room functions with one radio wave dark room. CONSTITUTION:For example, when an antenna evaluation test is performed, it is necessary to make a floor as non-reflection surface. Trucks 1-16 each with a radio wave absorbent housed on a floor and a rack 35 of an absorbent storage 22 are moved within a radio wave dark room 21 sequentially through a guide rail set on the floor of the radio wave dark room 21 to cover the entire floor surface. As a result, a full radio wave anechoic chamber is formed with the floor surface thereof made as non-reflection surface and an antenna to be tested is set at an antenna positioner using an electric winch 24 to perform an evaluation test. Here, the truck 1 closes a through part for moving the trucks provided on a partition wall between the storage 22 and the dark room 21. The storage 22 is arranged in a shield chamber, so there is no need for a shield wall to be established as the wall between the storage 22 and the dark chamber 21, thereby enabling the curtailment of costs. Then, an EMI noise measurement requires the floor to be a reflection surface and the trucks 1-16 are housed into the storage 22.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an anechoic chamber5, and particularly to an anechoic chamber suitable for realizing two or more functions such as EMI and antenna evaluation at low cost. It is something.

(Prior Art) In recent years, as electronic devices have become increasingly integrated into ICs, electromagnetic wave pollution has become a serious problem, such as electronic devices malfunctioning or computer data being corrupted by electromagnetic waves generated by electronic devices. As a measure against electromagnetic waves, an EMI anechoic chamber is used as a facility to accurately measure electromagnetic noise (EMI7 noise) generated from electronic devices. This EM
The anechoic chamber for I has a structure in which pyramid-shaped radio wave absorbers are attached to the walls and ceiling to prevent reflections from the walls, transmitting and receiving antennas are placed at predetermined positions, and the specimen is placed on a turntable. (For example, measure EMI noise generated from electronic equipment, etc.). A plan view of this conventional anechoic chamber for EMI is shown in FIG. In FIG. 7, 71 is an anechoic chamber, 72 is a radio wave absorber attached to a wall or ceiling (not shown), 73 is a shield surface, and 74 is a specimen (such as an electronic device) or a specimen A turntable 75 is used to place a mounted automobile or the like, an antenna positioner 176 and 77 are used to install a transmitting and receiving antenna (not shown), and 77 are doors. In this EMI anechoic chamber, the floor structure needs to be a reflective surface, so no radio wave absorber or the like is installed on the floor surface.

On the other hand, in the anechoic chamber where antenna evaluation tests are performed, accurate antenna evaluation is not possible due to reflections from the floor.
The floor structure must have a non-reflective surface. Therefore, in addition to the structure of the anechoic chamber shown in Fig. 7, the anechoic chamber for antenna evaluation has a radio wave absorber attached to the entire floor surface.
Two antenna positioners were installed, one with a transmitting antenna and the other with a receiving antenna, and antenna evaluation tests were conducted.

(Problem to be Solved by the Invention) However, since the conventional anechoic chamber described above has only a single function, two or more anechoic chambers for EMI noise measurement, antenna evaluation test, and EMS evaluation test are separated. It is necessary to conduct EMI noise measurements, antenna evaluation tests, etc., which raises the problem of high construction costs.

The purpose of the present invention is to solve such conventional problems and to perform EMI noise measurement, antenna evaluation test, and EMI noise measurement in one facility.
The objective is to provide an anechoic chamber that can conduct MS evaluation tests and keep construction costs low.

(Means for Solving the Problem) In order to achieve the above object, the anechoic chamber of the present invention has a structure in which radio wave absorbers are attached to the walls and ceiling, and a plurality of radio wave absorbers arranged on the floor. The absorber storage for storing the body-equipped carts has an integrated shield structure with the radio anechoic chamber, and a plurality of guide rails are laid on the floor for moving the plurality of radio wave absorber-equipped carts, and the absorber storage An elevating device with a transfer device is installed under the floor of the warehouse to transfer the carts with each radio wave absorber and lift and store them on a shelf in the absorber storage. If a plurality of the radio wave absorber-equipped trolleys are stored on a shelf in the absorber storage, a pulling machine is provided to pull in and send out each radio wave absorber-equipped trolley between the radio wave absorber storage and the radio anechoic chamber, Each trolley with radio wave absorber is transferred and lowered to the floor using the lifting device with transfer device, and then sent into the anechoic chamber along the guide rail by the pulling machine, and the trolley with radio wave absorber is placed over the entire floor surface. is placed as a non-reflection floor surface to constitute an anechoic chamber for antenna evaluation tests or EMS evaluation tests, and the plurality of carts with radio wave absorbers are arranged on the entire floor of the anechoic chamber. The above-mentioned pull-in machine pulls each cart with a radio wave absorber into the above-mentioned absorber storage, transfers each cart with a radio wave absorber onto the above-mentioned elevating device with a transfer device, lifts it, and stores it on the above-mentioned shelf. Carts with radio wave absorbers that cannot be stored on the shelves are stored on the floor. By storing all the carts with radio wave absorbers in the L7 anechoic chamber in the absorber storage, the floor can be used as a reflective surface for EMI noise measurement. The feature is that it constitutes an anechoic chamber.

In the anechoic chamber, the partition wall between the absorber storage and the anechoic chamber should not be used as a shield wall, and the opening at the boundary between the absorber storage and the anechoic chamber should be closed so that the Another feature is that it is equipped with a cart equipped with a radio wave absorber that absorbs radio wave reflections.

Further, the radio wave absorber-equipped cart has a plurality of guide wheels rotating on the plurality of guide rails and a plurality of deflection limiting wheels that reduce deflection of the cart, and has two types of radio wave absorbers. The feature is that absorbers having different absorption characteristics as described above are attached.

(Function) In the present invention, an absorber storage for storing a plurality of carts with radio wave absorbers placed on the floor has an integrated shield structure with the anechoic chamber, and the plurality of carts with radio wave absorbers are arranged on the floor. A plurality of guide rails are laid for movement, and a transfer device is installed to transfer each radio wave absorber-equipped trolley under the floor of the absorber storage, and lift and store it on a shelf in the absorber storage. A lifting device is installed, and a pulling machine for pulling in and sending out each cart with radio wave absorber between the absorber storage and the radio anechoic chamber is installed in the absorber storage described in 2. When a plurality of carts with radio wave absorbers are stored on the shelf, each cart with radio wave absorber is transferred by the lifting device with transfer device and lowered to the floor, and the guide is carried out by the pulling machine. The above radio waves are sent into an anechoic chamber along a rail, and a cart with a radio wave absorber is placed over the entire floor surface, and the floor surface is used as a non-reflection surface to configure a radio anechoic chamber for antenna evaluation tests or EMS evaluation tests. If the plurality of carts with radio wave absorbers are arranged on the entire floor surface of the darkroom, each cart with radio wave absorber is pulled into the absorber storage by the pulling machine, and the lifting device with transfer device is installed. The carts with radio wave absorbers that cannot be stored on the shelves are stored on the shelves described in ``Transfer and lift each trolley with radio wave absorbers to the anechoic chamber. By configuring an anechoic chamber for EMI noise measurement by storing all the carts in the absorber storage and using the floor as a reflective surface, two or more anechoic chamber functions can be realized in one anechoic chamber.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIGS. 1(a) and 1(b) are cross-sectional structural views of an anechoic chamber showing an embodiment of the present invention, and FIGS. 2(a) and 2(b) are plan views of the anechoic chamber. Here, Figures 1 (a) and 2 (a) are examples of placing a cart with a radio wave absorber on the floor and making the floor a non-reflective surface for antenna evaluation tests or EMS evaluation tests. 1(b) and 2(b) show an example in which a cart with a radio wave absorber is stored in an absorber storage for EMI noise measurement, and the floor surface is used as a reflective surface.

In Fig. 1 (a), (b) and Fig. 2 (a), (b), 1 to 16 are carts with radio wave absorbers, 17 is a fixed radio wave absorber, 20 is a measurement room, and 21 is an anechoic chamber. , 22 is an absorber storage for storing the radio wave absorber-equipped carts 1 to 16, and 23 is an absorber storage for storing the carts 1 to 12, which are lifted vertically to a shelf 35.
A lifting device with a transfer device 24, which lowers the carts 1 to 12 stored in the shelves 35, is normally waiting outside the anechoic chamber 21, and before measurement, heavy objects are placed on the hook at the tip of the wire lobe. 25 is a radio wave absorber, 26 is a shield surface,
28.29 is a transmitting antenna (
Antenna positioners 530, 31 for installing a receiving antenna (not shown) or a receiving antenna (not shown) are guide rails for guiding the carts 1 to 16, and 32, 33 are guide rails 30.
34 is a door, 35 is an antenna body 5 in which a transmitting/receiving antenna (not shown) is installed during the EMI noise measurement test, and 36 is a turntable. Here, the absorbent body storage 22 has a plurality of shelves arranged in two rows, front and rear.

FIG. 3 is a diagram showing an example in which a cart with a radio wave absorber is arranged in a radio anechoic chamber. This shows the state in which only the truck portion of FIG. 2(a) has been extracted. In addition, the trolley 1 is shown in Figure 4.
16 into the absorbent body storage 22 is shown. The pulling machine 41 shown in FIG.
2 is pulled in, and each cart is placed on the lifting device 23 with a transfer device. This elevating device 23 with a transfer device lifts each cart and stores it on a shelf 35.

In this embodiment, by switching the function of the floor surface between a non-reflective surface and a reflective surface, it becomes possible to perform an EMI noise measurement test, an antenna evaluation test, etc. in one anechoic chamber. This makes it possible to construct an anechoic chamber without incurring high construction costs.

First, a case in which an antenna evaluation test is performed will be explained.

For example, when carts 1 to 12 with radio wave absorbers are stored on the shelf 35 of the absorber storage 22 (see FIG. 1(b)), the carts 13 to 12 on the floor of the absorber storage 22 are stored. 16 into the anechoic chamber 21 and move the guide 1 nord 30.31 soil. Next, the shelf 35 and soil trolley 1 are moved by the lifting device 23 with the transfer device.
After placing ~12 on the device one by one and lowering it to the floor,
It is moved into the anechoic chamber 21 on the guide rails 30 and 31. Then, the state as shown in FIG. 1(a) and FIG. 2(a) will be obtained. This creates a completely radio anechoic chamber with the floor as a non-contact surface. Next, use the electric winder 25 or the like to move the transmitting antenna and the receiving antenna to the antenna positioners 28, 29.
The antenna evaluation test is performed while monitoring the inside of the anechoic chamber 21 using the measurement chamber 20.

Furthermore, if a cart with a radio wave absorber is already placed on the floor of the anechoic chamber 21 to form a completely anechoic chamber, antennas are installed on the antenna positioners 28 and 29 and an antenna evaluation test is performed. 43 in this antenna evaluation test,
Since the walls of the radio anechoic chamber 21 and the absorber storage 22 are penetrated through the bottom part of the wall for the carriage to pass through, a radio wave absorber is installed to close this penetration part and absorb the radio waves reflected from the absorber storage 22. An attached trolley is placed. This is done by arranging the trolley 1. Furthermore, absorbent material storage 22
Since it is provided in the shield room, the partition wall between the absorber storage 22 and the anechoic chamber 21 does not need to be a shield wall, resulting in a cost reduction effect.

FIGS. 5(a) and 5(b) are diagrams showing an example of a connector for a cart with a radio wave absorber. When moving the cart, holes 52 are provided on both sides of the cart, and the cart is connected with hooks 51 (see Fig. 5).
(see FIG. 5(b)), or by attaching vertical connecting fittings 53 to the cart (see FIG. 5(b)). The height h of the cart is as shown in Figure 1 (a) and (b) of the absorbent material storage 2.
It is set slightly shorter than the height h' between the shelves 35 in 2.

FIG. 6(a) is a cross-sectional view of the cart with a radio wave absorber, and FIG. 6(b) is a rear view thereof. Figure 6 (a), (b)
! ;l: Good, 61.62 is guide rail 3o, 3
1, a metal (for example, iron) guide wheel that rotates along 1; 63, a resin deflection limiting wheel to prevent the trolley from deflecting; 64, a radio wave absorber higher than the surrounding area;
5 is a low radio wave absorber. The radio wave absorbers 64 and 65 are attached (and hung) to the radio wave absorber-equipped trolley using magic fasteners, etc. This trolley has a structure in which four guide wheels and eight deflection limiting axles are attached. However, the number is not limited to this, and an appropriate number may be attached depending on the size of the trolley.The size of the trolley or the number of units may be determined depending on the performance of the lifting device with transfer device 23. For example, the length is 11.4 m and the radius is 1.2 m.
degree.

Next, a case in which an EMI noise measurement test is performed will be described.

First, it is assumed that the state of the anechoic chamber before the EMI noise measurement test is as shown in FIGS. 1(a) and 2(a). In this state, the floor surface of the anechoic chamber 21 is a non-reflective surface (accordance standard), and therefore is not suitable for EMI noise measurement. Therefore, the pulling machine 41 pulls the carts 1 to 16 into the absorbent body storage 22, and the carts 1 to 12 are
The units are placed one by one on the lifting device with transfer device 23, lifted and stored on the shelf 35. The carts 13 to 15 are simply moved and stored in the absorbent body storage 22. Note that the trolley 16 closes the penetration part between the anechoic chamber 21 and the absorber storage 22,
It is arranged at a position that absorbs radio wave reflection from the absorber storage 22. Therefore, the direction of the radio wave absorber on the cart 16 is slightly different from the direction of the radio wave absorbers on the other carts 2 to 15.

By storing the carts 1 to 15 in the absorber storage 22 as described above, the state of the anechoic chamber becomes as shown in FIG. 1(b) and FIG. 2(b). Here, the floor surface is a reflective surface.

In such an anechoic chamber, a desk (for example, made of wood, etc.) that does not reflect radio waves is placed on the turntable 36, a test object (for example, an electronic device, etc.) is placed on it, and a transmitting/receiving antenna is placed on the antenna positioner 35. (not shown) is installed in the measurement room 2, and the operator measures EMI noise from the specimen.
Do this while monitoring at 0.

In this way, in this example, the anechoic chamber and the absorber storage are integrated, the whole is shielded, and the partition wall between the anechoic chamber and the absorber storage is not a shield wall, but a guiding wall is placed on the floor. By laying rails and moving carts with radio wave absorbers to place them on the entire floor, or by storing them in the absorber storage, the floor can be switched to a non-reflective or reflective surface, making it possible to create a single radio anechoic chamber. It is possible to realize two or more darkroom functions and keep construction costs low.

In the above embodiment, the number of trolleys with radio wave absorbers is 16, but the number is not limited to this (the number may be changed depending on the size of the radio anechoic chamber2, and the absorber storage The number of shelves, etc., may also be changed.In the above embodiments, the carts are stored intermittently or continuously.

(Effects of the Invention) As explained above, according to the present invention, two or more darkroom functions can be realized in one anechoic chamber by switching to a non-reflective surface or a reflective surface such as the floor, thereby reducing construction costs. can be kept low.

[Brief explanation of the drawing]

FIG. 1(a) is a cross-sectional structural diagram of an anechoic chamber for antenna evaluation tests, etc., showing an embodiment of the present invention, and FIG. 1(b) is a diagram of an anechoic chamber for EMI measurement, showing an embodiment of the present invention. Figure 2 (a) is a cross-sectional structural diagram;
Figure (b) is a plan view of the anechoic chamber shown in Figure 1 (b), Figure 3 is a diagram showing an example of a cart with a radio wave absorber placed inside the anechoic chamber, and Figure 4 is a diagram for explaining the retraction machine. Figure 5(a),
(b) is a diagram showing an example of a coupling device for a cart with a radio wave absorber, Figures 6 (a) and (b) are a cross-sectional view and rear view of a cart with a radio wave absorber, and Figure 7 is a conventional anechoic chamber. FIG. 1 to 16: Trolley with radio wave absorber, 17: Fixed radio wave absorber, 21: Radio wave anechoic chamber, 22: Absorber storage, 23: Lifting device with transfer device, 24: Electric hoist, 25: Radio wave absorption Body, 26: Shield surface, 2g, 29: Antenna positioner, 30, 31: Guide rail, 32, 33 8 groove, 34: Door,
35: antenna positioner, 36: turntable, 41: retractor, 51: hook,
52: Hole, 53: Connecting fitting, 61.62:
Guide wheel, 63: Deflection limiting wheel, 64: Radio wave absorber, 65: Radio wave absorber.

Claims (4)

[Claims] (1) In an anechoic chamber with a structure in which radio wave absorbers are attached to the walls and ceiling, an absorber storage that stores a plurality of trolleys with radio wave absorbers placed on the floor has an integrated shield structure with the anechoic chamber, A plurality of guide rails are laid on the floor to move the plurality of carts with radio wave absorbers, and each cart with radio wave absorber is transferred to the under floor of the absorber storage. A lifting device with a transfer device is installed to lift and store the radio wave absorber on a shelf inside the storage cabinet, and a pull-in device is installed inside the absorber storage cabinet to pull in and send out each cart with a radio wave absorber between the absorber storage cabinet and the radio anechoic chamber. If a plurality of carts with radio wave absorbers are stored on a shelf in the absorber storage, each cart with radio wave absorbers is transferred using the lifting device with transfer device and placed on the floor. It is lowered to the surface and sent into the anechoic chamber along the guide rail by the retracting machine, and a cart with a radio wave absorber is placed over the entire floor surface to use as a non-reflective surface for antenna evaluation tests or EMS.
When an anechoic chamber for evaluation tests is configured and a plurality of carts with radio wave absorbers are arranged on the entire floor of the anechoic chamber, each cart with a radio wave absorber is moved by the pulling machine to the absorber. Pull into the storage room, transfer each cart with radio wave absorber to the lifting device with transfer device, lift it up and store it on the shelf above, and place the cart with radio wave absorber that cannot be stored on the shelf above on the floor. 1. A radio anechoic chamber characterized in that a radio anechoic chamber for EMI noise measurement is constructed by storing all carts with radio wave absorbers in the radio anechoic chamber in an absorber storage with the floor surface as a reflective surface. (2) The anechoic chamber according to claim 1, wherein the partition wall between the absorber storage and the anechoic chamber is not a shield wall. (3) A cart with a radio wave absorber is disposed to close an opening at the boundary between the absorber storage and the radio wave anechoic chamber and absorb radio wave reflection from the absorber storage. The anechoic chamber described in item 2. (4) The cart with a radio wave absorber has a plurality of guide wheels rotating on the plurality of guide rails and a plurality of deflection limiting wheels that reduce deflection of the cart, and has two wheels as radio wave absorbers. 4. The anechoic chamber according to claim 1, 2 or 3, further comprising absorbers having different absorption characteristics.