JP2021129039A - Radio wave shield chamber and radio wave test method - Google Patents

Abstract

To provide a radio wave shield chamber capable of suppressing the irregular reflection of radio waves due to dew condensation water in a chamber.SOLUTION: A radio wave shield chamber includes: a chamber; a first partition wall partitioning the space in the chamber into an inner space where a test piece is disposed and an outer space surrounding the inner space, the first partition wall being capable of transmitting radio waves therethrough; a temperature control unit controlling the temperature of the inner space; and a dehumidification part dehumidifying the outer space.SELECTED DRAWING: Figure 1

Description

The present invention relates to a radio wave shield chamber and a radio wave test method.

Conventionally, as described in Patent Document 1, a radio wave shield chamber used for a performance evaluation test of a communication device or the like is known. This radio wave shield chamber is designed so that radio waves do not enter the chamber from the outside and the radio waves do not leak from the inside of the chamber to the outside. It is called an anechoic chamber).

In the anechoic chamber described in Patent Document 1, a radio wave absorber is arranged on the inner surface of the electromagnetic shield chamber, and a cover surrounding an electronic device as a test body is arranged inside the electromagnetic shield chamber, and is outside the electromagnetic shield chamber. The temperature of the space inside the cover can be adjusted by the air conditioning equipment arranged in. As a result, the performance evaluation test is performed while the ambient temperature of the electronic device is kept constant.

Japanese Patent No. 4440002

In the anechoic chamber described in Patent Document 1, the following problems may occur when the space inside the cover is tested in a state of being temperature-controlled to a low temperature. That is, when low-temperature air is supplied from the air-conditioning equipment to the space inside the cover via a duct, the cover is also cooled by the low-temperature air, and the temperature of the outer surface of the cover is changed to the outer space (between the outer surface of the cover and the radio wave absorber). The temperature may drop below the dew point temperature of the space). In this case, dew condensation water is generated on the outer surface of the cover, and there arises a problem that radio waves are diffusely reflected by the dew condensation water in the chamber.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a radio wave shield chamber and a radio wave test method capable of suppressing diffused reflection of radio waves due to dew condensation water in the chamber.

The radio wave shield chamber according to one aspect of the present invention is a first partition wall that divides the chamber and the space inside the chamber into an inner space in which a test piece is arranged and an outer space surrounding the inner space, and is a radio wave. It is provided with the first partition wall capable of permeating the space, a temperature control unit for controlling the temperature of the inner space, and a dehumidifying unit for dehumidifying the outer space.

According to this radio wave shield chamber, the humidity of the outer space inside the chamber can be lowered by the dehumidifying portion. Therefore, by adjusting the temperature of the inner space in the chamber to a low temperature by the temperature control unit, even if the outer surface temperature of the first partition wall is lowered, it is possible to prevent the outer surface temperature from becoming lower than the dew point temperature of the outer space. can. As a result, the generation of dew condensation water on the outer surface of the first partition wall is suppressed, and the diffused reflection of radio waves due to the dew condensation water in the chamber can be suppressed.

In the radio wave shield chamber, the dehumidifying section is formed with a dry gas generating section arranged outside the chamber and a dry gas supply port for supplying the dry gas generated in the dry gas generating section to the outer space. It may include a dry gas supply chamber.

According to this configuration, the outer space can be easily dehumidified by using a dry gas. Further, when the radio wave absorber is arranged in the outer space, it is possible to suppress the deterioration of the performance of the radio wave absorber due to the high humidity environment and the condensed water.

The radio wave shield chamber may further include a dry gas control unit that controls the dry gas generation unit based on the set temperature of the inner space or the measurement temperature of the inner space.

According to this configuration, when the set temperature of the inner space or the measured temperature thereof is low and the outer surface temperature of the first partition wall tends to decrease, the dry gas is supplied to the outer space to condense water on the outer surface of the first partition wall. The occurrence can be suppressed more reliably. Further, when the set temperature of the inner space or the measured temperature thereof is high, energy saving can be achieved by stopping the supply of the dry gas to the outer space.

The radio wave shield chamber is a dry gas generating unit so that the dry gas is supplied to the outer space when the set temperature of the inner space or the measured temperature of the inner space is equal to or lower than the dew point temperature of the outer space. A dry gas control unit for controlling the temperature may be further provided.

According to this configuration, the timing of supplying the dry gas to the outer space is adjusted in consideration of the dew point temperature of the outer space, so that the generation of dew condensation water can be suppressed more reliably.

In the radio wave shield chamber, the dehumidifying section may further include a dry gas discharge path for discharging the dry gas from the outer space to the outside of the chamber. The dry gas discharge path may be formed with a dry gas discharge port that opens in the outer space and a dry gas discharge port that opens in the outer space of the chamber.

According to this configuration, since the dry gas can be discharged to the external space of the chamber, the equipment can be simplified and the cost can be reduced as compared with the configuration in which the dry gas is circulated.

In the radio wave shield chamber, the dehumidifying section may further include a dry gas discharge path for discharging the dry gas from the outer space to the outside of the chamber. The dehumidifying section may be configured to circulate the dry gas to the dry gas generating section via the dry gas discharge path.

According to this configuration, the humidity of the outer space can be adjusted more reliably by circulating the dry gas.

The radio wave shield chamber may further include a gas guide plate that forms a flow of the dry gas so that the dry gas orbits the outer space.

According to this configuration, even when the dry gas supply port and the dry gas discharge port are brought close to each other, the dry gas can be distributed over a wide range of the outer space. Then, by bringing the dry gas supply port and the dry gas discharge port close to each other, the duct length of the dry gas supply path and the dry gas discharge path can be suppressed when the circulation type dehumidifying unit is used.

The radio wave shield chamber may be attached to the dry gas supply port, and may further include a shield member through which the dry gas can pass and which reflects radio waves.

According to this configuration, it is possible to supply the dry gas from the dry gas supply port to the outer space, and it is possible to suppress the leakage of radio waves to the outside of the chamber through the dry gas supply port.

The radio wave shield chamber may further include a heating portion for heating the dry gas or the first partition wall.

According to this configuration, the temperature of the first partition wall can be raised by supplying the heated dry gas to the outer space or heating the first partition wall. As a result, even when the inner space is in a high temperature and high humidity state, it is possible to suppress the generation of dew condensation water on the inner surface of the first partition wall.

The radio wave shield chamber may further include a heating control unit that controls the heating unit based on at least a set temperature of the inner space or at least a measurement temperature of the inner space and a measurement temperature of the outer space. ..

According to this configuration, the timing of heating the dry gas can be adjusted in consideration of the measurement temperature of the outer space and at least the set temperature or at least the measurement temperature of the inner space, so that the inner space is in a high temperature and high humidity state. Even so, it is possible to more reliably suppress the generation of dew condensation water on the inner surface of the first partition wall.

The radio wave shield chamber may further include a heating control unit that controls the heating unit based on at least a set temperature in the inner space or at least a measured temperature in the inner space.

According to this configuration, the heating control can be further simplified as compared with the case where the heating of the dry gas is controlled in consideration of both the temperature of the outer space and at least the set temperature or at least the measurement temperature of the inner space.

In the radio wave shield chamber, the dry gas for dehumidifying the outer space and the dry gas or the first partition wall are heated by the heating unit based on at least the measured temperature of the inner space or at least the set temperature of the inner space. A switching unit for switching between the heated state and the heating state may be further provided.

According to this configuration, it is possible to efficiently dehumidify and heat the inside of the chamber so that the generation of dew condensation water can be suppressed on both the inner surface and the outer surface of the first partition wall.

The radio wave shield chamber according to another aspect of the present invention is a first partition wall that divides the chamber and the space inside the chamber into an inner space in which a test piece is arranged and an outer space surrounding the inner space. It includes the first partition wall capable of transmitting radio waves, a temperature control unit for controlling the temperature of the inner space, and a heating unit for heating the first partition wall.

According to this radio wave shield chamber, the temperature of the first partition wall can be raised by the heating unit. Therefore, even when the inner space inside the chamber is in a high temperature and high humidity state, it is possible to prevent the inner surface temperature of the first partition wall from becoming lower than the dew point temperature of the inner space. This makes it possible to suppress the generation of dew condensation water on the inner surface of the first partition wall and suppress the diffused reflection of radio waves due to the dew condensation water in the chamber.

The radio wave shield chamber has a second partition wall that partitions the outer space into a first outer space that surrounds the inner space and a second outer space in which an antenna that transmits and receives radio waves between the test piece can be arranged. May be further provided. The second partition wall may be configured to allow radio waves to pass through.

According to this configuration, even when the inner space is in a high temperature and high humidity state and the temperature of the first outer space is raised in order to suppress dew condensation on the inner surface of the first partition wall, the temperature of the second outer space is set to the second. 1 It can be kept lower than the temperature of the outer space. As a result, when an antenna having low heat resistance is arranged in the outer space, it is possible to prevent the antenna from being thermally damaged.

In the radio wave test method according to still another aspect of the present invention, at least the test body of the test body and the antenna for transmitting and receiving radio waves between the test body and the test body is partitioned by a first partition wall in an inner space. And, among the outer spaces surrounding the inner space, the state of transmitting and receiving radio waves between the test piece and the antenna while installing the inner space and controlling the temperature of the inner space and dehumidifying the outer space. To evaluate and include.

In this method, the transmission / reception state of radio waves between the test piece and the antenna is evaluated while controlling the temperature of the inner space in the chamber and dehumidifying the outer space. Therefore, even if the outer surface temperature of the first partition wall is lowered by adjusting the temperature of the inner space to a low temperature according to the test conditions, it is possible to prevent the outer surface temperature from becoming lower than the dew point temperature of the outer space. As a result, it is possible to suppress the generation of dew condensation water on the outer surface of the first partition wall and suppress the diffused reflection of radio waves due to the dew condensation water in the chamber.

In the radio wave test method according to still another aspect of the present invention, at least the test body of the test body and the antenna for transmitting and receiving radio waves between the test body and the test body is partitioned by a first partition wall in an inner space. And, while installing in the inner space among the outer spaces surrounding the inner space, controlling the temperature of the inner space and heating the first partition wall, radio waves between the test body and the antenna are transmitted. Including to evaluate the transmission / reception status.

In this method, the transmission / reception state of radio waves between the test piece and the antenna is evaluated while controlling the temperature of the inner space in the chamber and heating the first partition wall. Therefore, even when the test is performed in a state where the inner space is high temperature and high humidity, it is possible to prevent the inner surface temperature of the first partition wall from becoming lower than the dew point temperature of the inner space. This makes it possible to suppress the generation of dew condensation water on the inner surface of the first partition wall and suppress the diffused reflection of radio waves due to the dew condensation water in the chamber.

As is clear from the above description, according to the present invention, it is possible to provide a radio wave shield chamber and a radio wave test method capable of suppressing diffused reflection of radio waves due to dew condensation water in the chamber.

It is a figure which shows typically the structure of the radio wave shield chamber which concerns on Embodiment 1 of this invention. It is a flowchart for demonstrating the radio wave test method which concerns on Embodiment 1 of this invention. It is a flowchart for demonstrating the operation control of the dry air unit in the modification of Embodiment 1 of this invention. It is a flowchart for demonstrating the operation control of the dry air unit in Embodiment 2 of this invention. It is a figure which shows typically the structure of the radio wave shield chamber which concerns on Embodiment 3 of this invention. It is a figure which shows typically the structure of the radio wave shield chamber which concerns on Embodiment 4 of this invention. It is a figure which shows typically the structure of the radio wave shield chamber which concerns on Embodiment 5 of this invention. It is a flowchart for demonstrating the radio wave test method which concerns on Embodiment 5 of this invention. It is a flowchart for demonstrating control of a dry air unit and a heating part in Embodiment 6 of this invention. It is a flowchart for demonstrating the control of the dry air unit and the heating part in the modification of Embodiment 6 of this invention. It is a figure which shows typically the structure of the radio wave shield chamber which concerns on Embodiment 8 of this invention. It is a figure which shows typically the structure of the radio wave shield chamber which concerns on Embodiment 9 of this invention.

Hereinafter, the radio wave shield chamber and the radio wave test method according to the embodiment of the present invention will be described in detail with reference to the drawings.

(Embodiment 1)
First, the configuration of the radio wave shield chamber 1 according to the first embodiment of the present invention will be described with reference to FIG. The radio wave shield chamber 1 is used for performance evaluation of, for example, a communication device or an in-vehicle module that uses high frequency radio waves. As shown in FIG. 1, the radio wave shield chamber 1 includes a chamber 10, a first partition wall 30, a radio wave absorber 40, a temperature control unit 50, a dehumidifying unit 60, a shield member 80, and a control unit 70. Is mainly prepared. Hereinafter, each of these components will be described.

The chamber 10 is a box body in which the space 20 is formed inside, and is configured to be capable of suppressing the intrusion of radio waves from the outside of the chamber into the space 20 and the leakage of radio waves from the space 20 to the outside of the chamber. The chamber 10 includes an outer box 11 and an inner box 12 arranged inside the outer box 11 with an air layer 10A sandwiched between the outer box 11. The outer box 11 and the inner box 12 are made of a conductive material such as a stainless steel plate, and are each grounded. Further, a heat insulating material 13 made of urethane foam or the like is provided on the outer surface of the outer box 11 (the surface facing the side opposite to the air layer 10A).

The first partition wall 30 partitions the space 20 in the chamber 10 into an inner space 21 and an outer space 22 surrounding the inner space 21. Specifically, the first partition wall 30 is composed of a box body smaller than the inner box 12, and a test body S1 such as a communication device or an in-vehicle module is arranged in the inner space 21. The first partition wall 30 is capable of transmitting radio waves transmitted and received by the test body S1, and for example, a foam material such as expanded polystyrene or a resin material such as FRP (Fiber Reinforced Plastics) is used, but the first partition wall 30 is not limited thereto. Further, an inner temperature sensor 23 and an inner humidity sensor 24 are arranged in the inner space 21, and an outer temperature sensor 25 and an outer humidity sensor 26 are arranged in the outer space 22.

The radio wave absorber 40 is, for example, a mixture of urethane foam or the like with carbon powder, and absorbs radio waves due to dielectric loss (dielectric radio wave absorber). The radio wave absorber 40 is arranged in the outer space 22, and specifically, is provided on the inner surface of the inner box 12 (the surface facing the outer space 22 side) (FIG. 1). The radio wave absorber 40 is not limited to the dielectric radio wave absorber, and for example, the radio wave absorber is made of a conductive fiber and absorbs radio waves by the resistance inside the material, or the radio wave is transmitted by magnetic loss of a ferrite core or the like. It may be a magnetic radio wave absorber that absorbs.

The temperature control unit 50 controls the temperature of the inner space 21, and includes a temperature control unit 51, an air supply duct 52, and an air discharge duct 53. The temperature control unit 51 has equipment such as a heater, a refrigerator, a humidifier, and a fan (not shown), and generates conditioned air in which the temperature and humidity are controlled.

One end of the air supply duct 52 is connected to the air outlet of the temperature control portion 51, and extends to the inner space 21 through the heat insulating material 13, the outer box 11, the inner box 12, and the first partition wall 30. .. An air supply port 52A that opens into the inner space 21 is formed at the other end of the air supply duct 52 (the end opposite to the one end connected to the temperature control portion 51). The conditioned air whose temperature and humidity are adjusted by the temperature control unit 51 flows through the air supply duct 52 and is then supplied from the air supply port 52A to the inner space 21.

One end of the air discharge duct 53 is connected to the air inlet of the temperature control portion 51, and like the air supply duct 52, penetrates the heat insulating material 13, the outer box 11, the inner box 12, and the first partition wall 30. It extends to the inner space 21. An air discharge port 53A that opens into the inner space 21 is formed at the other end of the air discharge duct 53 (the end opposite to the one end connected to the temperature control portion 51).

The air in the inner space 21 is discharged from the air discharge port 53A into the air discharge duct 53, and returns to the air inlet of the temperature control unit 51 through the air discharge duct 53. In this way, the conditioned air whose temperature and humidity are adjusted circulates between the temperature control portion 51 and the inner space 21 via the air supply duct 52 and the air discharge duct 53.

The dehumidifying section 60 dehumidifies the outer space 22. The dehumidifying section 60 in the present embodiment includes a dry gas generating section 61 arranged outside the chamber 10, a dry gas supply path 62 for supplying the dry gas generated by the dry gas generating section 61 to the outer space 22, and an outer space. Includes a dry gas discharge path 63 for discharging the dry gas from 22 to the outside of the chamber 10.

The dry gas generating unit 61 is composed of, for example, a dry air unit, and generates dry air by removing water from compressed air with a hygroscopic agent such as silica gel. The dry gas generating unit 61 may be one that removes water with a cooler, or may be a dry dehumidifier. One end of the dry gas supply path 62 is connected to the outlet of the dry gas generating section 61, and extends through the heat insulating material 13, the outer box 11, and the inner box 12 to the outer space 22. At the other end of the dry gas supply path 62 (the end opposite to the one end connected to the dry gas generation unit 61), the outer space 22 is opened and the dry gas generated by the dry gas generation unit 61 (the dry gas (the end opposite to the one end)). A dry gas supply port 62A for supplying dry air) to the outer space 22 is formed. The dry gas supply path 62 is composed of, for example, a duct.

The dry gas discharge path 63 is formed with a dry gas discharge port 63A that opens in the outer space 22 and a dry gas discharge port 63B that is open in the outer space (in the atmosphere) of the chamber 10. The dry air supplied into the outer space 22 is discharged to the outside of the chamber 10 through the dry gas discharge path 63, and then is discharged into the atmosphere from the dry gas discharge port 63B.

As shown in FIG. 1, the dry gas discharge port 63A is located on the side opposite to the side where the dry gas supply port 62A is located with the space 20 of the chamber 10 interposed therebetween. Specifically, the dry gas discharge path 63 penetrates the wall 15 facing the wall 14 through which the dry gas supply path 62 penetrates among the plurality of walls constituting the chamber 10. The dry gas supply port 62A and the dry gas discharge port 63A are located so as to sandwich the inner space 21. The dry gas supply port 62A and the dry gas discharge port 63A may or may not face each other.

The shield member 80 is a member through which air can pass and reflects radio waves, and as shown in FIG. 1, the shield member 80 has an air supply port 52A, an air discharge port 53A, a dry gas supply port 62A, and a dry gas discharge port 63A. Each is attached. As a result, air conditioning air can flow through the air supply port 52A and the air discharge port 53A, dry air can flow through the dry gas supply port 62A and the dry gas discharge port 63A, and dry air can flow through these four openings. Leakage of radio waves is also suppressed. The shield member 80 is not an essential component of the radio wave shield chamber of the present invention, and measures for preventing radio wave leakage from the opening may be taken by other commonly used methods.

The control unit 70 is a controller that controls various operations in the radio wave shield chamber, and includes a reception unit 71, a storage unit 72, a determination unit 73, a temperature control unit 75, and a dry gas control unit 76. The reception unit 71, the determination unit 73, the temperature control unit 75, and the dry gas control unit 76 are functions executed by the central processing unit (CPU) of the controller. The storage unit 72 is composed of a storage device such as a memory.

The reception unit 71 receives measurement data signals from each of the inner temperature sensor 23, the inner humidity sensor 24, the outer temperature sensor 25, and the outer humidity sensor 26. The storage unit 72 stores data on the set temperature and the set humidity of the inner space 21. Further, the storage unit 72 also stores reference data (for example, a dry gas supply reference temperature) for determining whether or not to supply the dry gas to the outer space 22.

The determination unit 73 compares the set temperature / humidity data of the inner space 21 acquired from the storage unit 72 with the measured temperature / humidity data of the inner space 21 acquired from the reception unit 71, and determines the magnitude relationship thereof. Further, the determination unit 73 compares the data of the set temperature of the inner space 21 acquired from the storage unit 72 with the data of the dry gas supply reference temperature, and determines the magnitude relationship between them.

The temperature control unit 75 controls the operation of the temperature control unit 51 based on the determination result (result of comparison determination between the set temperature / humidity of the inner space 21 and the measured temperature / humidity of the inner space 21) by the determination unit 73. Specifically, the temperature control control unit 75 controls (feedback) the outputs of the heater, the refrigerator, and the humidifier based on the above determination results so that the actual temperature and humidity of the inner space 21 approaches the set temperature and humidity. Control.

The dry gas control unit 76 in the present embodiment controls the dry gas generation unit 61 (dry air unit) based on the set temperature of the inner space 21. Specifically, the dry gas control unit 76 operates the dry air unit based on the determination result by the determination unit 73 (the result of the comparison determination between the set temperature of the inner space 21 and the dry gas supply reference temperature).

Next, the radio wave test method according to the present embodiment will be described with reference to the flowchart of FIG. In this radio wave test method, the transmission / reception state of radio waves between the test body S1 and the antenna S2 is evaluated while controlling the temperature of the inner space 21 in the chamber 10 and dehumidifying the outer space 22 as follows.

First, the test body S1 (for example, a communication device such as a smartphone, an in-vehicle module, etc.) is installed in the inner space 21, and the antenna S2 is installed in the outer space 22 (step S10). The antenna S2 transmits and receives radio waves to and from the test body S1.

Next, the temperature (test temperature) of the inner space 21 in the chamber 10 is set (step S20). In the present embodiment, for example, the set temperature of the inner space 21 is set to −40 ° C.

Next, the temperature control unit 50 is operated (step S30). In step S30, the temperature control unit 75 operates the temperature control unit 51 so that the temperature of the inner space 21 approaches the set temperature while circulating the conditioned air between the temperature control unit 51 and the inner space 21. Control. Specifically, the temperature of the inner space 21 is measured by the inner temperature sensor 23, and when the measured temperature is higher than the set temperature, the temperature control control unit 75 lowers the output of the heater or raises the output of the refrigerator. .. On the other hand, when the measured temperature of the inner space 21 is lower than the set temperature, the temperature control control unit 75 raises the output of the heater or lowers the output of the refrigerator.

On the other hand, after the temperature of the inner space 21 is set in step S20, the determination unit 73 determines whether or not the set temperature of the inner space 21 is equal to or lower than the dry gas supply reference temperature (step S40). In the present embodiment, the dry gas supply reference temperature is set in advance to, for example, 10 ° C. Therefore, the determination unit 73 determines that the set temperature (minus 40 ° C.) of the inner space 21 is equal to or lower than the dry gas supply reference temperature (10 ° C.) (YES in step S40).

Based on the above determination result, the dry gas control unit 76 operates the dry air unit (step S50). As a result, dry air is supplied to the outer space 22 and the outer space 22 is dehumidified. As a result, the dew point temperature of the outer space 22 is lowered.

In this way, while controlling the temperature of the inner space 21 and dehumidifying the outer space 22 in parallel, the transmission / reception state of radio waves between the test body S1 and the antenna S2 is evaluated. Specifically, the antenna S2 receives the radio wave emitted from the test body S1 and evaluates whether or not an appropriate radio wave is emitted from the test body S1. Further, it is evaluated whether or not the test body S1 receives the radio wave emitted from the antenna S2. Then, when the test termination condition is satisfied (YES in step S60), the operation of the temperature control unit 50 and the dry air unit is stopped, and the radio wave test method is terminated.

On the other hand, when the test end condition is not satisfied (NO in step S60), the determination returns to step S40. Then, when the set temperature of the inner space 21 is changed during the test and the changed set temperature is higher than the dry gas supply reference temperature (NO in step S40), the dry gas control unit 76 operates the dry air unit. Stop (step S70). After that, when the set temperature of the inner space 21 is changed again until the end condition of the test is satisfied and the set temperature after the change is equal to or lower than the dry gas supply reference temperature (YES in step S40), the dry gas control The unit 76 restarts the operation of the dry air unit (step S50).

As described above, according to the radio wave shield chamber 1 according to the present embodiment, the humidity of the outer space 22 in the chamber 10 can be lowered by the dehumidifying unit 60. Therefore, even if the outer surface temperature of the first partition wall 30 is lowered by adjusting the temperature of the inner space 21 in the chamber 10 to a low temperature (for example, −40 ° C.), the outer surface temperature becomes lower than the dew point temperature of the outer space 22. Can be suppressed. That is, the outer space 22 can be dehumidified so that the dew point temperature of the outer space 22 drops below the outer surface temperature of the first partition wall 30. As a result, the generation of dew condensation water on the outer surface of the first partition wall 30 can be suppressed, and the diffused reflection of radio waves due to the dew condensation water in the chamber 10 can be suppressed. Further, it is possible to suppress the deterioration of the performance of the radio wave absorber 40 due to the condensed water.

If the first partition wall 30 is formed thick to improve the heat insulating performance in order to suppress the decrease in the outer surface temperature of the first partition wall 30, the radio wave transmission performance of the first partition wall 30 deteriorates. On the other hand, in the present embodiment, since the dry air is supplied to the outer space 22, it is not necessary to form the first partition wall 30 thickly. Therefore, it is possible to suppress the generation of dew condensation water on the outer surface of the first partition wall 30 while suppressing the deterioration of the radio wave transmission performance of the first partition wall 30.

Here, a modified example of the present embodiment will be described.

<Modification example 1>
In the present embodiment, the case where the dry air unit is controlled based on the set temperature of the inner space 21 has been described, but the dry gas control unit 76 has the dry gas control unit 76 based on the measured temperature of the inner space 21 (measured value of the inner space sensor 23). The dry air unit may be controlled. Specifically, the control shown in the flowchart of FIG. 3 may be executed.

Steps S11 to S31 in FIG. 3 are the same as steps S10 to S30 in FIG. In this modification, after the operation of the temperature control unit 50 is started in step S31, the temperature of the inner space 21 is measured by the inner temperature sensor 23 at all times or at predetermined time intervals, and the measured temperature is the dry gas supply reference temperature (dry gas supply reference temperature). For example, the determination unit 73 determines whether or not the temperature is 10 ° C. or lower (step S41).

For example, when the set temperature is low and the temperature of the inner space 21 is not sufficiently lowered immediately after the start of operation of the temperature control unit 50, the measured temperature of the inner space 21 is lower than the dry gas supply reference temperature. Is also determined to be high (NO in step S41). In this case, the dry air unit remains in the stopped state (step S71), and if "NO" is determined in step S61, the process returns to step S41.

Then, when a certain time elapses from the start of operation of the temperature control unit 50, the measurement temperature of the inner space 21 drops, and it is determined that the measurement temperature is equal to or lower than the dry gas supply reference temperature (YES in step S41). In this case, the dry gas control unit 76 starts the operation of the dry air unit (step S51).

Then, until the end condition of the test is satisfied, the determination in step S41 is repeated, but as long as the measurement temperature of the inner space 21 is kept below the dry gas supply reference temperature, the operation of the dry air unit is continued. .. According to this modification, the dry air unit is maintained in a stopped state until the temperature of the inner space 21 drops below the dry gas supply reference temperature, so that the dry air unit is operated at the same time as the temperature control of the inner space 21 is started. Power saving can be achieved as compared with the case.

<Modification 2>
In step S40 in FIG. 2, it may be determined whether or not the set temperature of the inner space 21 is equal to or lower than the measured temperature of the outer space 22. Then, when the set temperature of the inner space 21 is equal to or lower than the measurement temperature of the outer space 22, the dry air unit is started (or continues to operate), and when the set temperature of the inner space 21 is higher than the measurement temperature of the outer space 22. The dry air unit may be stopped (or the operation may be continued).

<Modification example 3>
In step S41 in FIG. 3, it may be determined whether or not the measured temperature of the inner space 21 is equal to or lower than the measured temperature of the outer space 22. Then, when the measurement temperature of the inner space 21 is equal to or lower than the measurement temperature of the outer space 22, the dry air unit is started (or continues to operate), and when the measurement temperature of the inner space 21 is higher than the measurement temperature of the outer space 22. The dry air unit may be stopped (or the operation may be continued).

(Embodiment 2)
Next, the radio wave shield chamber and the radio wave test method according to the second embodiment of the present invention will be described. The radio wave shield chamber and the radio wave test method according to the second embodiment are basically the same as those in the first embodiment, but when the set temperature of the inner space 21 is equal to or lower than the dew point temperature of the outer space 22, dry air is sent to the outer space 22. Is different in that the dry gas control unit 76 controls the dry air unit so that Hereinafter, only the points different from the first embodiment will be described.

In the second embodiment, the control unit 70 further includes a calculation unit (not shown) in addition to the configuration described in the first embodiment. The calculation unit calculates the dew point temperature of the inner space 21 and the outer space 22 based on the temperature and humidity data of the inner space 21 and the outer space 22.

FIG. 4 shows a radio wave test method (control flow of the dry air unit by the control unit 70) in the second embodiment. Steps S12 to S32 in FIG. 4 are the same as steps S10 to S30 in FIG.

In the present embodiment, after the step S22, the temperature and humidity of the outer space 22 are constantly or at predetermined time intervals by the outer temperature sensor 25 and the outer humidity sensor 26, and based on the measurement result, the calculation unit is in the outer space. The actual dew point temperature of 22 is calculated. Then, in step S42, the determination unit 73 determines whether or not the set temperature of the inner space 21 is equal to or lower than the dew point temperature of the outer space 22.

When the set temperature of the inner space 21 (for example, −40 ° C.) is equal to or lower than the dew point temperature of the outer space 22 (YES in step S42), the dry gas control unit 76 starts the operation of the dry air unit (step S52). As a result, dry air is supplied to the outer space 22, and the humidity of the outer space 22 is lowered, so that the dew point of the outer space 22 is lowered.

The determination in step S42 is repeated until the end condition of the test is satisfied. Then, when it is determined that the dew point temperature of the outer space 22 is lowered by the supply of dry air and the set temperature of the inner space 21 is higher than the dew point temperature of the outer space 22 (NO in step S42), the dry gas control unit 76 is set to dry air. The operation of the unit is stopped (step S72). On the other hand, when the set temperature of the inner space 21 is still equal to or lower than the dew point temperature of the outer space 22 (YES in step S42), the dry gas control unit 76 continues the operation of the dry air unit (step S52).

As described above, in the present embodiment, the timing of supplying dry air to the outer space 22 is adjusted in consideration of the dew point temperature of the outer space 22. Therefore, it is possible to supply dry air to the outer space 22 at an appropriate timing after more accurately determining the necessity of dehumidification in the outer space 22.

As a modification of this embodiment, the supply of dry air to the outer space 22 is turned on based on the comparison result between the measured temperature of the inner space 21 (measured temperature of the inner space sensor 23) and the dew point temperature of the outer space 22. / Off may be controlled. That is, after step S22 in FIG. 4, the temperature of the inner space 21 is constantly measured or measured at predetermined time intervals, and in step S42, it is determined whether or not the measured temperature of the inner space 21 is equal to or lower than the dew point temperature of the outer space 22. The unit 73 may determine. Then, when the measured temperature of the inner space 21 is equal to or lower than the dew point temperature of the outer space 22, the dry gas control unit 76 starts (or continues) the operation of the dry air unit, and the measured temperature of the inner space 21 is the dew point of the outer space 22. The dry gas control unit 76 may stop (or continue to stop) the dry air unit when the temperature is higher than the temperature.

(Embodiment 3)
Next, the configuration of the radio wave shield chamber 3 according to the third embodiment of the present invention will be described with reference to FIG. The radio wave shield chamber 3 according to the third embodiment basically has the same configuration and the same effect as the radio wave shield chamber 1 according to the first and second embodiments, but is different in that dry air is circulated. ing. Hereinafter, only the points different from the first embodiment will be described.

The dehumidifying unit 60 in the present embodiment is configured to circulate dry air to the dry gas generating unit 61 via the dry gas discharge path 63 and to adjust the humidity of the dry air. Specifically, as shown in FIG. 5, the end of the dry gas discharge path 63 opposite to the dry gas discharge port 63A is connected to the inlet of the dry gas generation unit 61. As a result, the dry air circulates between the dry gas generating section 61 and the outer space 22 via the dry gas supply path 62 and the dry gas discharge path 63.

The dry gas generating unit 61 in the present embodiment has a built-in mechanism for removing water from the dry air (for example, a cooling dehumidifier using a refrigerating device, a desiccant type dehumidifier, or the like). Therefore, the dry air that has absorbed moisture in the outer space 22 is dehumidified in the dry gas generating unit 61 and is supplied to the outer space 22 again. The moisture removing mechanism operates based on the measured value of the outer humidity sensor 26, operates until the humidity of the outer space 22 becomes equal to or lower than a predetermined target humidity, and stops when the humidity becomes equal to or lower than the predetermined target humidity. Further, when the humidity of the outer space 22 becomes higher than a predetermined target humidity, the moisture removing mechanism is activated. In the present embodiment, the humidity of the outer space 22 can be adjusted more reliably by circulating the dry air while adjusting the humidity of the dry air.

The moisture removing mechanism may operate based on the dew point temperature calculated from the measured values of the outside temperature sensor 25 and the outside humidity sensor 26. In this case, the moisture removal mechanism operates until the calculated dew point temperature falls below the predetermined target temperature and stops when the calculated dew point temperature falls below the predetermined target temperature, and the calculated dew point temperature is higher than the predetermined target temperature. It works when it becomes.

(Embodiment 4)
Next, the configuration of the radio wave shield chamber 4 according to the fourth embodiment of the present invention will be described with reference to FIG. The radio wave shield chamber 4 according to the fourth embodiment basically has the same configuration as the radio wave shield chamber 3 according to the third embodiment, but further includes a gas guide plate 81 arranged in the outer space 22. Is different. Hereinafter, only the differences from the third embodiment will be described.

As shown in FIG. 6, in the present embodiment, the dry gas supply path 62 and the dry gas discharge path 63 penetrate the same wall (wall 14) among the plurality of walls constituting the chamber 10, and supply dry gas. The port 62A and the dry gas discharge port 63A are adjacent to each other. The gas guide plate 81 is arranged in the outer space 22 so as to be located between the dry gas supply port 62A and the dry gas discharge port 63A.

The gas guide plate 81 forms a flow of the dry air so that the dry air orbits the outer space 22. Specifically, as shown by the arrows in FIG. 6, the dry air supplied from the dry gas supply port 62A to the outer space 22 is outside in the order of the wall 14, the upper wall 16, the wall 15, and the lower wall 17 of the chamber 10. It flows through the space 22 and is then sucked into the dry gas discharge path 63 from the dry gas discharge port 63A.

Here, the flow of dry air in the outer space 22 in an arbitrary cross section (cross section including the walls 14, 15, the upper wall 16 and the lower wall 17) of the chamber 10 has been described, but the gas guide plate 81 is shown in FIG. It extends toward the front side of the paper surface and toward the back side of the paper surface. Therefore, the dry air supplied from the dry gas supply port 62A to the outer space 22 flows toward the upper wall 16 side and also flows along the gas guide plate 81 in the front direction of the paper surface and the back direction of the paper surface in FIG.

As described above, in the fourth embodiment, even when the dry gas supply port 62A and the dry gas discharge port 63A are brought close to each other, the dry air can be distributed over a wide range of the outer space 22. Therefore, the duct length of the dry gas discharge path 63 can be made shorter than in the case where the dry gas supply port 62A and the dry gas discharge port 63A are located on opposite sides of each other. Further, the gas guide plate 81 is preferably made of a material capable of transmitting radio waves.

(Embodiment 5)
Next, the configuration of the radio wave shield chamber 5 according to the fifth embodiment of the present invention will be described with reference to FIG. 7. The radio wave shield chamber 5 according to the fifth embodiment basically has the same configuration as the radio wave shield chamber 1 according to the first and second embodiments, but is different in that it further includes a heating unit 90 for heating dry air. ing. Hereinafter, only the points different from the first embodiment will be described.

The heating unit 90 is composed of, for example, a heater. As shown in FIG. 7, the heating unit 90 in this embodiment is arranged in the dry gas supply path 62. As a result, the dry air generated in the dry air unit (dry gas generating unit 61) is heated by the heating unit 90, and the dried air after the temperature rise is introduced into the outer space 22. As a result, the outer space 22 and the first partition wall 30 are heated. That is, the heating unit 90 in the present embodiment indirectly heats the first partition wall 30 by heating the dry air supplied to the outer space 22.

The control unit 70 in the present embodiment further includes a heating control unit 77 that controls the heating unit 90. The heating control unit 77 is one function of the CPU and controls the heater output of the heating unit 90. The heating control unit 77 in the present embodiment controls the heating unit 90 based on the set temperature and humidity of the inner space 21 and the temperature of the outer space 22. Further, the control unit 70 has a calculation unit 74. The calculation unit 74 calculates the dew point temperature of the inner space 21 and the outer space 22 based on the temperature and humidity data of the inner space 21 and the outer space 22.

Next, the radio wave test method according to the present embodiment implemented using the radio wave shield chamber 5 will be described with reference to the flowchart of FIG. In this radio wave test method, the transmission / reception state of radio waves between the test body S1 and the antenna S2 is evaluated while controlling the temperature of the inner space 21 and heating the first partition wall 30 as follows.

First, similarly to the first embodiment, the test body S1 is installed in the inner space 21 and the antenna S2 is installed in the outer space 22 (step S13). Next, the temperature and humidity of the inner space 21 in the chamber 10 are set (step S23). In the present embodiment, as an example, the set temperature of the inner space 21 is set to 85 ° C., and the set humidity of the inner space 21 is set to 85% (relative humidity).

Next, the temperature control unit 50 is operated (step S33). The temperature control of the inner space 21 is as described in the first embodiment, but in the present embodiment, the humidity of the inner space 21 is also adjusted as follows. Specifically, the humidity of the inner space 21 is measured by the inner humidity sensor 24, and when the measured humidity is higher than the set humidity, the temperature control unit 75 lowers the output of the humidifier. On the other hand, when the measured humidity in the inner space 21 is lower than the set humidity, the temperature control unit 75 increases the output of the humidifier.

On the other hand, after step S23, the temperature of the outer space 22 is constantly or at predetermined time intervals by the outer temperature sensor 25. Then, in step S43, the determination unit 73 determines whether or not the measured temperature of the outer space 22 is equal to or lower than the set dew point temperature of the inner space 21. Here, the set dew point temperature is calculated by the calculation unit 74 based on the set temperature / humidity (85 ° C., 85% in the present embodiment) of the inner space 21, and is, for example, 83 ° C. in the present embodiment.

In the present embodiment, the temperature of the outer space 22 is near room temperature immediately after the start of the test. Therefore, it is determined that the measured temperature of the outer space 22 is equal to or lower than the set dew point temperature of the inner space 21 (YES in step S43), the dry gas control unit 76 starts the operation of the dry air unit, and the heating control unit 77 starts the operation of the dry air unit. 90 is activated (step S53). As a result, the heated dry air is supplied to the outer space 22, and the temperature of the outer space 22 and the first partition wall 30 rises.

Then, when a certain amount of time has passed from the operation of the dry air unit and the start of operation of the heating unit 90, the measured temperature in the outer space 22 rises, and the measured temperature becomes higher than the set dew point temperature (83 ° C.) in the inner space 21 (step). NO of S43). In this case, the dry gas control unit 76 stops the operation of the dry air unit, and the heating control unit 77 stops the heating unit 90 (step S73). The determination in step S43 is repeated until the test end condition is satisfied, but until the measured temperature in the outer space 22 exceeds the set dew point temperature in the inner space 21, the operation of the dry air unit and the operation of the heating unit 90 are performed. To continue.

As described above, in the present embodiment, the temperature of the first partition wall 30 can be raised by supplying the heated dry air to the outer space 22. Therefore, even if the inner space 21 in the chamber 10 is in a high temperature and high humidity state (for example, 85 ° C., 85%), it is possible to prevent the inner surface temperature of the first partition wall 30 from becoming lower than the dew point temperature of the inner space 21. can do. This makes it possible to suppress the generation of dew condensation water on the inner surface of the first partition wall 30 and suppress the diffused reflection of radio waves due to the dew condensation water in the chamber 10.

Here, a modified example of the present embodiment will be described.

<Modification example 1>
In the present embodiment, the set dew point temperature is calculated based on the set temperature and humidity of the inner space 21, and the dry air unit and the heating unit 90 are controlled based on the comparison result between the set dew point temperature and the measured temperature of the outer space 22. , Control based on the measured temperature and humidity of the inner space 21 (measured values by the inner temperature sensor 23 and the inner humidity sensor 24) may be executed. Specifically, after step S23 in FIG. 8, the temperature and humidity of the inner space 21 are measured at all times or at predetermined time intervals, and the actual dew point temperature of the inner space 21 is calculated by the calculation unit 74 based on the measured values. May be done. Then, in step S43, it may be determined whether or not the measured temperature of the outer space 22 is equal to or lower than the actual dew point temperature of the inner space 21, and the dry air unit and the heating unit 90 may be controlled based on the determination result.

<Modification 2>
In step S43 in FIG. 8, it may be determined whether or not the measured temperature of the outer space 22 is equal to or lower than the measured temperature of the inner space 21. Then, when the measurement temperature of the outer space 22 is equal to or lower than the measurement temperature of the inner space 21, the dry air unit and the heating unit 90 are started (or continue to operate), and the measurement temperature of the outer space 22 is the measurement temperature of the inner space 21. When the temperature is higher than the above, the dry air unit and the heating unit 90 may be stopped (or the operation may be continued). In the second modification, the set temperature of the inner space 21 may be used instead of the measurement temperature of the inner space 21.

<Other modifications>
In step S53 in FIG. 8, the heating unit 90 may be operated in a state where the ventilation function of the dry air unit is on and the dehumidification function is off. In this case, the undehumidified air is heated by the heating unit 90 and supplied to the outer space 22, but the outer space 22 and the first partition wall 30 are similarly heated.

Further, the heating unit 90 may have an air blowing function. In this case, in step S53, the heating air is supplied to the outer space 22 by turning off both the ventilation function and the dehumidification function of the dry air unit (stopping the operation) and turning on the heating function and the ventilation function of the heating unit 90. You may. In this case as well, the outer space 22 and the first partition wall 30 are heated in the same manner.

The heating unit 90 is not limited to the case where it is arranged in the dry gas supply path 62, and may be a heater built in the dry air unit (dry gas generation unit 61). Further, a bypass path (not shown) having both ends connected to the dry gas supply path 62 may be provided, and the heating unit 90 may be arranged in this bypass path.

The heating unit 90 described in this embodiment can also be applied to the radio wave shield chambers 3 and 4 according to the third and fourth embodiments.

(Embodiment 6)
Next, the radio wave shield chamber according to the sixth embodiment of the present invention will be described. The radio wave shield chamber according to the sixth embodiment basically has the same configuration as the radio wave shield chamber 5 according to the fifth embodiment, but is based on the set temperature and humidity of the inner space 21 without using the measured temperature of the outer space 22. It differs in that it controls the dry air unit and the heating unit 90. Hereinafter, only the points different from the above-described fifth embodiment will be described.

FIG. 9 shows the control flow of the dry air unit and the heating unit 90 in this embodiment. Steps S14 to S34 in FIG. 9 are the same as steps S13 to S33 in FIG.

In the present embodiment, in step S44, the determination unit 73 determines whether or not the set dew point temperature of the inner space 21 is equal to or higher than the heating reference temperature. The set dew point temperature is calculated based on the temperature and humidity set in step S24. The heating reference temperature is a reference temperature for determining the necessity of supplying the heated dry air, and is set to, for example, 30 ° C. The data of the heating reference temperature is stored in the storage unit 72.

When the set dew point temperature of the inner space 21 is equal to or higher than the heating reference temperature (YES in step S44), the dry gas control unit 76 starts the operation of the dry air unit, and the heating control unit 77 operates the heating unit 90 (step). S54). On the other hand, when the set dew point temperature of the inner space 21 is lower than the heating reference temperature (NO in step S44), the dry air unit and the heating unit 90 are left in the stopped state. Then, when the predetermined test end condition is satisfied (YES in step S64), the radio wave test is ended.

On the other hand, when the test end condition is not satisfied (NO in step S64), the determination returns to the determination in step S44. Then, when the set temperature / humidity of the inner space 21 is changed during the test, whether or not the set dew point temperature of the inner space 21 calculated based on the changed set temperature / humidity is equal to or higher than the heating reference temperature. It is judged. When the dry air unit and the heating unit 90 are in operation, if the set dew point temperature of the inner space 21 is equal to or higher than the heating reference temperature, the operation of the dry air unit and the heating unit 90 is continued, while the set dew point temperature is the heating reference temperature. If the temperature is lower than the temperature, the operation of the dry air unit and the heating unit 90 is stopped (step S74). When the dry air unit and the heating unit 90 are stopped, if the set dew point temperature of the inner space 21 is equal to or higher than the heating reference temperature, the operation of the dry air unit and the heating unit 90 is started, while the set dew point temperature is set. When the temperature is lower than the heating reference temperature, the operation of the dry air unit and the heating unit 90 is maintained in the stopped state.

<Modification example 1>
FIG. 10 shows the control flow of the dry air unit and the heating unit 90 in the first modification of the sixth embodiment. The heating control unit 77 may control the heating unit 90 based on the measured temperature and humidity of the inner space 21 instead of the set temperature and humidity of the inner space 21.

Steps S15 to S35 in FIG. 10 are the same as steps S14 to S34 in FIG. In this modification, after step S25, the temperature and humidity of the inner space 21 are measured at all times or at predetermined time intervals, and the calculation unit 74 calculates the actual dew point temperature of the inner space 21 based on the measurement result.

Then, in step S45, it is determined whether or not the actual dew point temperature of the inner space 21 is equal to or higher than the heating reference temperature. When the actual dew point temperature of the inner space 21 is equal to or higher than the heating reference temperature (YES in step S45), the dry gas control unit 76 starts the operation of the dry air unit and the heating control unit 77 operates the heating unit 90 (step). S55). On the other hand, when the actual dew point temperature of the inner space 21 is lower than the heating reference temperature (NO in step S45), the dry air unit and the heating unit 90 are stopped (step S75).

In this modification, the determination in step S45 is repeated until the end condition of the test is satisfied. Then, the dry air unit and the heating unit 90 are stopped while the actual dew point temperature of the inner space 21 is lower than the heating reference temperature, and the dry air unit and the heating unit 90 are constantly operated while the actual dew point temperature of the inner space 21 is equal to or higher than the heating reference temperature.

<Modification 2>
In step S44 in FIG. 9, it may be determined whether or not the measured temperature of the inner space 21 is equal to or higher than the heating reference temperature. Then, when the measurement temperature of the inner space 21 is equal to or higher than the heating reference temperature, the operation of the dry air unit and the heating unit 90 is started (or the operation is continued), and when the measurement temperature of the inner space 21 is lower than the heating reference temperature, the dry air is started. The unit and the heating unit 90 may be stopped (or the operation may be continued). Further, in the second modification, the set temperature of the inner space 21 may be used instead of the measurement temperature of the inner space 21.

(Embodiment 7)
Next, the radio wave shield chamber according to the seventh embodiment of the present invention will be described. The radio wave shield chamber according to the seventh embodiment basically has the same configuration as the radio wave shield chamber 5 according to the fifth embodiment, but has a dry state for dehumidifying the outer space 22 and dry air or a first partition by the heating unit 90. The difference is that the wall 30 is further provided with a switching portion for switching between the heated state in which the wall 30 is heated and the heated state. Hereinafter, only the points different from the above-described fifth embodiment will be described.

The switching unit switches between the dry state and the heated state based on at least the measured temperature of the inner space 21 or at least the set temperature of the inner space 21, and specifically, the following patterns (1) to (1) to ( Each switching control of 6) is performed.

First, in the pattern (1), the switching unit switches between the dry state and the heated state based only on the measured temperature of the inner space 21. Specifically, when the measurement temperature of the inner space 21 is equal to or higher than a predetermined reference temperature (for example, 25 ° C.), the switching unit is the dry gas control unit 76 and the heating control unit so that the dry air unit and the heating unit 90 operate. A control signal is sent to each of the 77. On the other hand, when the measured temperature of the inner space 21 is lower than the reference temperature, the switching unit is connected to the dry gas control unit 76 and the heating control unit 77 so that the dry air unit operates and the heating unit 90 stops. Send a control signal.

The reference temperature may have a predetermined range, for example, 15 ° C. or higher and 35 ° C. or lower. In this case, when the measured temperature of the inner space 21 becomes equal to or higher than the upper limit of the temperature range, the heating state is switched to, and when the measured temperature of the inner space 21 becomes equal to or lower than the lower limit of the temperature range, the drying state is switched to. .. In the switching control of the pattern (1), the set temperature of the inner space 21 may be used instead of the measurement temperature of the inner space 21.

Next, in the pattern (2), the switching unit switches between the dry state and the heated state based on the measured temperature and the measured humidity of the inner space 21. Specifically, the calculation unit 74 calculates the dew point temperature of the inner space 21 based on the measured temperature and the measured humidity of the inner space 21, and when the dew point temperature becomes equal to or higher than a predetermined reference temperature, the dry air unit and the heating unit The switching unit sends a control signal to each of the dry gas control unit 76 and the heating control unit 77 so that the 90 operates. On the other hand, when the dew point temperature of the inner space 21 falls below a predetermined reference temperature, the switching unit is assigned to each of the dry gas control unit 76 and the heating control unit 77 so that the dry air unit operates and the heating unit 90 stops. Send a control signal. In the switching control of the pattern (2), the set temperature / humidity of the inner space 21 may be used instead of the measured temperature / humidity of the inner space 21.

Next, in the pattern (3), the switching unit switches between the dry state and the heated state based on the measurement temperature of the inner space 21 and the measurement temperature of the outer space 22. Specifically, when the measurement temperature of the inner space 21 is higher than the measurement temperature of the outer space 22, the switching unit is the dry gas control unit 76 and the heating control unit 77 so that the dry air unit and the heating unit 90 operate. Send a control signal to. On the other hand, when the measurement temperature of the inner space 21 is lower than the measurement temperature of the outer space 22, the switching unit is the dry gas control unit 76 and the heating control unit 77 so that the dry air unit operates and the heating unit 90 stops. Send a control signal to each of them. In the switching control of the pattern (3), the set temperature of the inner space 21 may be used instead of the measurement temperature of the inner space 21.

Next, in the pattern (4), the switching unit switches between the dry state and the heated state based on the measured temperature of the inner space 21, the measured humidity of the inner space 21, and the measured temperature of the outer space 22. Specifically, the calculation unit 74 calculates the dew point temperature of the inner space 21 based on the measured temperature and the measured humidity of the inner space 21, and when the dew point temperature is higher than the measured temperature of the outer space 22, the dry air unit and The switching unit sends a control signal to each of the dry gas control unit 76 and the heating control unit 77 so that the heating unit 90 operates. On the other hand, when the measurement temperature of the inner space 21 is lower than the measurement temperature of the outer space 22, the switching unit is the dry gas control unit 76 and the heating control unit 77 so that the dry air unit operates and the heating unit 90 stops. Send a control signal to each of them. In the switching control of the pattern (4), the set temperature and the set humidity of the inner space 21 may be used instead of the measured temperature and the measured humidity of the inner space 21. In this case, the switching unit switches between the dry state and the heated state based on the comparison between the set dew point temperature of the inner space 21 and the measured temperature of the outer space 22 calculated based on the set temperature and humidity.

Next, in the pattern (5), the switching unit switches between the dry state and the heated state based on the measured temperature of the inner space 21, the measured temperature of the outer space 22, and the measured humidity of the outer space 22. Specifically, when the measurement temperature of the inner space 21 is higher than the measurement temperature of the outer space 22, the switching unit is the dry gas control unit 76 and the heating control unit 77 so that the dry air unit and the heating unit 90 operate. Send a control signal to. On the other hand, the calculation unit 74 calculates the dew point temperature of the outer space 22 based on the measured temperature and the measured humidity of the outer space 22, and when the dew point temperature is higher than the measured temperature of the inner space 21, the dry air unit operates and The switching unit sends a control signal to each of the dry gas control unit 76 and the heating control unit 77 so that the heating unit 90 is stopped. In the switching control of the pattern (5), the set temperature of the inner space 21 may be used instead of the measurement temperature of the inner space 21.

Finally, in the pattern (6), the switching unit is in the dry state and the heated state based on the measured temperature of the inner space 21, the measured humidity of the inner space 21, the measured temperature of the outer space 22, and the measured humidity of the outer space 22. To switch between. Specifically, the calculation unit 74 calculates the dew point temperature of the inner space 21 based on the measured temperature and the measured humidity of the inner space 21, and when the dew point temperature is higher than the measured temperature of the outer space 22, the dry air unit and The switching unit sends a control signal to each of the dry gas control unit 76 and the heating control unit 77 so that the heating unit 90 operates. On the other hand, the calculation unit 74 calculates the dew point temperature of the outer space 22 based on the measured temperature and the measured humidity of the outer space 22, and when the dew point temperature is higher than the measured temperature of the inner space 21, the dry air unit operates and The switching unit sends a control signal to each of the dry gas control unit 76 and the heating control unit 77 so that the heating unit 90 is stopped. In the switching control of the pattern (6), the set temperature and the set humidity of the inner space 21 may be used instead of the measured temperature and the measured humidity of the inner space 21. In this case, the switching unit switches between the dry state and the heated state based on the comparison between the set dew point temperature of the inner space 21 and the measured temperature of the outer space 22 calculated based on the set temperature and humidity.

In the present embodiment, the case where both the dry air unit and the heating unit 90 are operated in the above heating state has been described, but in the above patterns (1) to (6), the dry air unit is stopped and the heating unit 90 is operated. You may. Specifically, as described in the modified example of the fifth embodiment, the outer space 22 and the first partition wall 30 may be heated by using the air heating function and the ventilation function of the heating unit 90. Further, the heating unit 90 that directly heats the first partition wall 30 without passing through air may be operated.

(Embodiment 8)
Next, the configuration of the radio wave shield chamber 7 according to the eighth embodiment of the present invention will be described with reference to FIG. The radio wave shield chamber 7 according to the eighth embodiment basically has the same configuration as the radio wave shield chamber 5 according to the fifth embodiment, except that the second partition wall 91 for partitioning the outer space 22 is further provided. ing. Hereinafter, only the points different from the above-described fifth embodiment will be described.

The second partition wall 91 partitions the outer space 22 into a first outer space 22A surrounding the inner space 21 and a second outer space 22B into which the antenna S2 can be arranged. As shown in FIG. 11, the dry gas supply port 62A and the dry gas discharge port 63A are open to the first outer space 22A. Therefore, the dry air heated by the heating unit 90 is supplied to the first outer space 22A, but is not supplied to the second outer space 22B. The second partition wall 91 is made of a material capable of transmitting radio waves.

According to the above configuration, the inner space 21 is in a high temperature and high humidity state, and is heated to the first outer space 22A in order to suppress dew condensation on the inner surface (the surface facing the inner space 21 side) of the first partition wall 30. Even when the dry air is supplied, the temperature of the second outer space 22B can be maintained lower than the temperature of the first outer space 22A. As a result, when the antenna S2 having low heat resistance is arranged in the second outer space 22B, it is possible to prevent the antenna S2 from being thermally damaged. The second partition wall 91 described in the present embodiment can also be applied to the above-described first to seventh embodiments.

(Embodiment 9)
Next, the radio wave shield chamber 9 according to the ninth embodiment of the present invention will be described with reference to FIG. The radio wave shield chamber 9 according to the ninth embodiment is basically the same as the radio wave shield chamber 5 according to the fifth and sixth embodiments, but is not provided with the dry gas generating unit 61 and has a configuration in which the heated gas circulates. It is different in that it is.

The heating unit 90 includes a blowing mechanism such as a fan and a heating mechanism such as a heater that heats a gas (for example, air) sent from the blowing mechanism. The heating control unit 77 controls the operation of the ventilation mechanism and the heating mechanism, respectively.

The radio wave shield chamber 9 includes a heated gas supply path 92 that supplies the heated gas from the heating unit 90 to the outer space 22, and a heated gas discharge path 93 that returns the heated gas discharged from the outer space 22 to the heating unit 90. ing. As shown in FIG. 12, the heated gas supply path 92 penetrates the heat insulating material 13, the outer box 11, and the inner box 12 and extends to the outer space 22, and supplies the heated gas from the supply port 92A to the outer space 22. .. On the other hand, the heated gas discharge path 93 also penetrates the heat insulating material 13, the outer box 11 and the inner box 12 and extends to the outer space 22, and the heated gas in the outer space 22 is discharged from the discharge port 93A to the heated gas discharge path 93. Will be done.

With the above configuration, the heated gas circulates between the heating unit 90 and the outer space 22 via the heated gas supply path 92 and the heated gas discharge path 93. Then, the outer space 22 and the first partition wall 30 are heated by the heated gas.

The heating unit 90 in the present embodiment is basically controlled by the same flow as in FIGS. 8 to 10. That is, the fans and heaters of the heating unit 90 are operated in steps S53, S54, and S55 of FIGS. 8 to 10, respectively, and the fans and heaters of the heating unit 90 are stopped in steps S73, S74, and S75 of the same figure, respectively.

<Modification example>
Although the case where the heated gas is circulated has been described in the ninth embodiment, the heated gas discharged from the outer space 22 may be released into the atmosphere. That is, the end of the heated gas discharge path 93 opposite to the discharge port 93A may be open to the atmosphere.

The heating unit 90 is not limited to indirectly heating the first partition wall 30 and the outer space 22 by heating the gas supplied to the outer space 22, and is not limited to a heater that directly heats the first partition wall 30 or the like. It may be.

Examples of the control pattern of the heating unit 90 include the following modifications.

In step S43 in FIG. 8, it may be determined whether or not the measured temperature of the inner space 21 is equal to or higher than a predetermined reference temperature. Then, when the measured temperature of the inner space 21 is equal to or higher than the reference temperature, the fan and heater of the heating unit 90 are started (or continued to operate), and when the measured temperature of the inner space 21 is lower than the reference temperature. The fan and heater of the heating unit 90 may be stopped (or the operation may be continued). At this time, the set temperature of the inner space 21 may be used instead of the measurement temperature of the inner space 21.

In step S43 in FIG. 8, it may be determined whether or not the set dew point temperature of the inner space 21 is equal to or higher than a predetermined reference temperature. Then, when the set dew point temperature of the inner space 21 is equal to or higher than the reference temperature, the fan and heater of the heating unit 90 are started (or continue to operate), and the set dew point temperature of the inner space 21 is lower than the reference temperature. Occasionally, the fan and heater of the heating unit 90 may be stopped (or the operation may be continued). At this time, instead of the set dew point temperature of the inner space 21, the actual dew point temperature of the inner space 21 calculated based on the measured temperature and the measured humidity of the inner space 21 may be used.

In step S43 in FIG. 8, it may be determined whether or not the measured temperature of the inner space 21 is equal to or higher than the measured temperature of the outer space 22. Then, when the measurement temperature of the inner space 21 is equal to or higher than the measurement temperature of the outer space 22, the fan and heater of the heating unit 90 are started (or continue to operate), and the measurement temperature of the inner space 21 is the measurement of the outer space 22. When the temperature is lower than the temperature, the fan and the heater of the heating unit 90 may be stopped (or the operation may be continued). At this time, the set temperature of the inner space 21 may be used instead of the measurement temperature of the inner space 21.

In step S43 in FIG. 8, it may be determined whether or not the set dew point temperature of the inner space 21 is equal to or higher than the measured temperature of the outer space 22. Then, when the set dew point temperature of the inner space 21 is equal to or higher than the measured temperature of the outer space 22, the fan and heater of the heating unit 90 are started (or continued to operate), and the set dew point temperature of the inner space 21 is the outer space 22. The operation of the fan and heater of the heating unit 90 may be stopped (or the operation may be continued) when the temperature is lower than the measured temperature of. At this time, instead of the set dew point temperature of the inner space 21, the actual dew point temperature of the inner space 21 calculated based on the measured temperature and the measured humidity of the inner space 21 may be used.

The second partition wall 91 described in the eighth embodiment can also be applied to the radio wave shield chamber 9 according to the ninth embodiment.

(Other embodiments)
Here, other embodiments of the present invention will be described.

Another example of the dehumidifying portion in the present invention is a hygroscopic agent such as silica gel arranged in the outer space 22. Further, although the dry air has been described as an example of the dry gas in the above embodiment, it is also possible to use another kind of dry gas such as an inert gas.

In the radio wave shield chamber according to each of the above embodiments, the radio wave absorber 40 may be omitted. Whether or not the radio wave absorber 40 is arranged in the chamber 10 may be determined according to the type of test performed using the radio wave shield chamber.

The radio wave shield chamber of the present invention includes not only a relatively small one for performing a radio wave test such as a smartphone, but also a large one (radio wave shield room) capable of accommodating a vehicle equipped with a communication module. Is done.

The dew point temperatures of the inner space 21 and the outer space 22 are not limited to those calculated by calculation based on the measured temperature / humidity or the set temperature / humidity, and may be directly detected using a dew point meter.

It should be understood that the embodiments disclosed this time are exemplary in all respects and are not restrictive. The scope of the present invention is shown not by the above description but by the scope of claims, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

1,3,4,5,7,9 Radio shield chamber 10 Chamber 20 Space 21 Inner space 22 Outer space 22A 1st outer space 22B 2nd outer space 30 1st partition wall 40 Radio absorber 50 Temperature control unit 60 Dehumidifying unit 61 Dry gas generator 62 Dry gas supply path 62A Dry gas supply port 63 Dry gas discharge path 63A Dry gas discharge port 63B Dry gas discharge port 76 Dry gas control unit 77 Heating control unit 80 Shield member 81 Gas guide plate 90 Heating unit 91 2nd partition wall S1 test piece S2 antenna

Claims (16)

With the chamber
A first partition wall that divides the space inside the chamber into an inner space in which a test piece is arranged and an outer space surrounding the inner space, and the first partition wall capable of transmitting radio waves.
A temperature control unit that controls the temperature of the inner space and
A radio wave shield chamber including a dehumidifying section for dehumidifying the outer space. The dehumidifying section includes a dry gas generating section arranged outside the chamber, a dry gas supply path formed with a dry gas supply port for supplying the dry gas generated in the dry gas generating section to the outer space, and the like. The radio wave shield chamber according to claim 1. The radio wave shield chamber according to claim 2, further comprising a dry gas control unit that controls the dry gas generation unit based on the set temperature of the inner space or the measurement temperature of the inner space. Dry gas control that controls the dry gas generating unit so that the dry gas is supplied to the outer space when the set temperature of the inner space or the measured temperature of the inner space is equal to or lower than the dew point temperature of the outer space. The radio wave shield chamber according to claim 2, further comprising a portion. The dehumidifying section further includes a dry gas discharge path for discharging the dry gas from the outer space to the outside of the chamber.
Any one of claims 2 to 4 is formed in the dry gas discharge path with a dry gas discharge port opened in the outer space and a dry gas discharge port opened in the outer space of the chamber. The radio wave shield chamber described in the section. The dehumidifying section further includes a dry gas discharge path for discharging the dry gas from the outer space to the outside of the chamber.
The radio wave shield chamber according to any one of claims 2 to 4, wherein the dehumidifying section is configured to circulate the dry gas to the dry gas generating section through the dry gas discharge path. The radio wave shield chamber according to claim 5 or 6, further comprising a gas guide plate that forms a flow of the dry gas so that the dry gas orbits the outer space. The radio wave shield chamber according to any one of claims 2 to 7, further comprising a shield member attached to the dry gas supply port, which allows the dry gas to pass through and reflects radio waves. The radio wave shield chamber according to any one of claims 1 to 8, further comprising a heating portion for heating the dry gas or the first partition wall. The radio wave shield chamber according to claim 9, further comprising a heating control unit that controls the heating unit based on at least a set temperature of the inner space or at least a measurement temperature of the inner space and a measurement temperature of the outer space. .. The radio wave shield chamber according to claim 9, further comprising a heating control unit that controls the heating unit based on at least a set temperature in the inner space or at least a measured temperature in the inner space. A dry state in which the outer space is dehumidified based on at least the measured temperature of the inner space or at least a set temperature of the inner space, and a heated state in which the dry gas or the first partition wall is heated by the heating unit. The radio wave shield chamber according to any one of claims 9 to 11, further comprising a switching unit for switching between. With the chamber
A first partition wall that divides the space inside the chamber into an inner space in which a test piece is arranged and an outer space surrounding the inner space, and the first partition wall capable of transmitting radio waves.
A temperature control unit that controls the temperature of the inner space and
A radio wave shield chamber including a heating unit for heating the first partition wall. A second partition wall for partitioning the outer space into a first outer space surrounding the inner space and a second outer space in which an antenna for transmitting and receiving radio waves can be arranged between the test piece is further provided.
The radio wave shield chamber according to any one of claims 1 to 13, wherein the second partition wall is configured to allow radio waves to pass through. Of the test body and the antenna that transmits and receives radio waves between the test body, at least the test body is placed in the inner space of the inner space partitioned by the first partition wall in the chamber and the outer space surrounding the inner space. To install and
A radio wave test method including evaluating the transmission / reception state of radio waves between the test body and the antenna while controlling the temperature of the inner space and dehumidifying the outer space. Of the test body and the antenna that transmits and receives radio waves between the test body, at least the test body is placed in the inner space of the inner space partitioned by the first partition wall in the chamber and the outer space surrounding the inner space. To install and
A radio wave test method including evaluating the transmission / reception state of radio waves between the test body and the antenna while controlling the temperature of the inner space and heating the first partition wall.

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