JP2005236595A - Interference rejection capability testing device and electromagnetic wave generator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electromagnetic wave generator, even when being a generator for radiating a radio wave of high electric field strength, which can use a conventional antenna of low withstand voltage and a conventional low with stand voltage and low output power amplifier; and to provide an electromagnetic wave generator which can obtain a uniform electromagnetic field distribution in a testing plane, even when being the electromagnetic wave generator which can radiate the radio wave of high electric field strength. <P>SOLUTION: The electromagnetic wave generator 17 includes a signal generator 10 for generating a high-frequency signal, a plurality of radiating antennas 5, a distributor 11 for distributing the signal outputted from the signal generator 10 to the radiating antennas 5, and power amplifiers 13 and an output level regulator 18 of the same numbers as the plurality of the antennas 5. After the output level is regulated by the output level regulator 18 so that the uniform electric field distribution is obtained in the testing plane, electromagnetic waves are respectively radiated from the corresponding radiating antennas 5. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention relates to a disturbance rejection capability test device for testing a disturbance rejection capability (also referred to as immunity) of an electronic device, and an electromagnetic wave generator used therefor.

Conventionally, the immunity test equipment has placed the EUT on a turntable that stands on one end of a radio semi-anechoic chamber whose floor is the ground plane, and the antenna is mounted on an antenna support column that stands on the other end of the ground plane. Provided.
Then, a wave absorber for blocking the electromagnetic wave reflected by the ground plane is provided below the direct wave path of the electromagnetic wave radiated from the antenna, and only the direct wave is exposed to the specified test plane where the EUT is placed. It is configured to let you. (For example, refer to Patent Document 1).
In addition, a specimen is placed in an anechoic chamber, and a radiated electromagnetic field test method in which horizontal or vertically polarized electromagnetic waves are applied to the specimen from a biconical antenna or a log-periodic antenna fixed in the same anechoic chamber. There is a TEM waveguide method using a cell and a GTEM cell. (For example, refer to Patent Document 2).

JP-A-7-55863 JP 2003-98211 A

However, in the proposed technology, even if the field strength of the test radio wave radiated from the antenna is relatively low (200 V / m) as the EUT, it can be sufficiently tolerated depending on the usage status of the product (EUT). There is no problem, however, for example, if a vehicle such as an automobile equipped with the product is driven near a guidance radar device used for taking off and landing of an aircraft, the on-board electronic device malfunctions and does not function correctly. In some cases, it was found that the problem of a fatal failure occurred.
In order to solve this problem, the inventors tried to increase the electric field strength of the test radio wave. However, the electric field strength of 600 V / m is necessary, and this is applied to a single amplifier, as in the proposed technique. When realized with an antenna, not only a high withstand voltage antenna is required, but also a high withstand voltage and high output power amplifying device is required. There was a problem that the apparatus also increased in size. In addition, there is a problem that the cost becomes high.
Therefore, the present application has been made to solve these problems. The purpose of the electromagnetic wave generator is an electromagnetic wave generator that can radiate a radio wave having a high electric field strength, and can use a conventional antenna with a low withstand voltage. It is to provide a generator.
Another object of the present invention is to provide an electromagnetic wave generator that can use a conventional power amplifying device with a low withstand voltage and a low output even if it is an electromagnetic wave generator that can radiate radio waves with high electric field strength.
Another object is to use an electromagnetic wave generator that can radiate radio waves with high electric field strength using multiple antennas and multiple power amplifiers. Is to provide.
Another object is to provide an electromagnetic wave generator that can be easily installed and maintained.
Another object is to provide an electromagnetic wave generator that can cover a wide frequency range of electromagnetic waves radiated to the EUT.
Another purpose is to obtain a uniform electromagnetic field distribution on the test plane, and to use a conventional low withstand voltage antenna and a conventional low withstand voltage / low output power amplifying device at low cost. It is to provide a test device.

In order to solve the above problems, the invention of claim 1 is an apparatus for generating an electromagnetic wave, wherein a signal generator for generating a high-frequency signal, a plurality of radiation antennas, and a signal output from the signal generator are transmitted to the radiation generator. A distributor for distributing to the antenna, a power amplifying device equal to the number of the plurality of radiating antennas, and an output level adjuster, and an output level at each of the output level adjusters so as to obtain a uniform electric field distribution on the test plane. After the adjustment, the electromagnetic waves are radiated from the corresponding radiating antennas.

According to a second aspect of the present invention, in the electromagnetic wave generating device according to the first aspect, the output level adjuster and the power amplifying device are configured to be housed in a single casing.

According to a third aspect of the present invention, in the electromagnetic wave generating device according to the first or second aspect, each of the radiating antennas is configured such that the radiation direction of the radiated electromagnetic wave is directed to the EUT.

According to a fourth aspect of the present invention, in the electromagnetic wave generating device according to the first to third aspects, the radiating antenna is a Yagi / Uda antenna, a helical antenna or an electromagnetic horn, and the frequency band of the radiated electromagnetic wave is a VHF band to It is configured to be in the SHF band.

According to a fifth aspect of the present invention, there is provided an interference immunity testing apparatus comprising: an anechoic chamber; a signal generator for generating a high frequency signal; a plurality of radiating antennas; a plurality of power amplifying devices; , A turntable for mounting the EUT on one end of the anechoic chamber, and a pedestal for installing the radiation antenna on the other end of the anechoic chamber. After the output level is adjusted by each of the output level adjusters so as to be distributed, electromagnetic waves are radiated from the corresponding radiating antennas toward the EUT.

As described above in detail, according to the first aspect of the present invention, in the apparatus for generating electromagnetic waves, the signal generator for generating a high-frequency signal, the plurality of radiation antennas, and the signal output from the signal generator are A distributor for distributing to the radiating antenna, the same number of power amplifying devices and output level adjusters as the plurality of radiating antennas, and an output level adjuster that outputs a uniform electric field distribution on the test plane. After adjusting the level, it was configured to radiate electromagnetic waves from each corresponding radiating antenna.
To provide an electromagnetic wave generator capable of using a conventional low withstand voltage antenna and capable of using a conventional low withstand voltage / low power amplifier even if it is an electromagnetic wave generator capable of radiating radio waves of high electric field strength. Can do. Also provided is an electromagnetic wave generator that can obtain a uniform electromagnetic field distribution in a test plane even if it is an electromagnetic wave generator that can emit radio waves with high electric field strength by using a plurality of antennas and a plurality of power amplifiers. be able to.

According to the invention of claim 2, in the electromagnetic wave generator of claim 1, the output level adjuster and the power amplifying device are configured to be housed in one housing.
It is possible to provide an electromagnetic wave generator that is easy to install and easy to maintain.

According to the invention of claim 3, in the electromagnetic wave generator according to claim 1 or claim 2, each radiating antenna is configured such that the radiation direction of the radiated electromagnetic wave is directed to the EUT.
To provide an electromagnetic wave generator capable of obtaining a uniform electromagnetic field distribution on a test plane even if it is an electromagnetic wave generator capable of radiating a radio wave having a high electric field strength by using a plurality of antennas and a plurality of power amplifiers. it can.

According to a fourth aspect of the present invention, in the electromagnetic wave generator according to the first to third aspects, the radiating antenna is a Yagi-Uda antenna, a helical antenna or an electromagnetic horn, and the frequency band of the radiated electromagnetic wave is VHF. Since it was configured to be a band to SHF band,
An object of the present invention is to provide an electromagnetic wave generator capable of covering a wide frequency range of electromagnetic waves radiated to a test equipment.

According to the invention of claim 5, in the interference rejection capability testing apparatus, the anechoic chamber, a signal generator for generating a high frequency signal, a plurality of radiating antennas, a plurality of power amplifiers, and a plurality of output level adjustments And a turntable for placing the equipment under test on one end of the anechoic chamber, and a pedestal for installing the radiation antenna on the other end of the anechoic chamber. After adjusting the output level with each of the output level adjusters so as to have a proper electric field distribution, it was configured to radiate electromagnetic waves from each corresponding radiating antenna toward the EUT.
Even a low-cost device using a conventional low withstand voltage antenna or a conventional low withstand voltage / low output amplifier can obtain a uniform electromagnetic field distribution on the test plane and can accurately eliminate interference. It is an object to provide a disturbance exclusion capability test apparatus capable of testing the above.

Hereinafter, an example of an embodiment embodying the present invention will be described in detail with reference to the drawings.

FIG. 1 is an explanatory diagram of a disturbance exclusion capability test apparatus to which the present invention is applied. FIG. 2 is a block diagram of the electromagnetic wave generator, and FIG. 3 is an explanatory diagram showing an installation example of the radiation antenna.
Reference numeral 1 denotes an interference immunity testing device, in which an electromagnetic wave absorber is attached to the entire surface of the anechoic chamber 7, and electromagnetic waves radiated into the anechoic chamber and electromagnetic waves reflected by the EUT. Is absorbed by the radio wave absorber and converted into thermal energy.
Inside the anechoic chamber 7, a turntable 3 is provided on one end side, and the EUT 2 is placed on the turntable 3. On the other end side, an antenna column 4 is provided via a gantry 6 so that the position of radiating radio waves can be changed. A plurality of radiation antennas 5 are installed on the antenna support 4. In this embodiment, in order to obtain a uniform electric field on the test plane, each radiation antenna 5 is installed such that the radiation direction thereof points to the EUT 2. By installing in this way, a uniform electric field can be obtained on the test plane, and electromagnetic waves can be concentrated in the vicinity of the EUT, and radiation efficiency can be improved.

Next, the electromagnetic wave generator 17 will be described in detail with reference to FIG. The electromagnetic wave generation device 17 includes a transmission device 15 and a radiation antenna 5. The transmitter 15 includes a signal generator 10, a distributor 11, a phase shifter 12, an output level adjuster 18, a power amplifier 13, and a circulator 14. Reference numeral 10 denotes a signal generator. In this embodiment, an oscillator that sweeps 1 to 1.5 GHz is used. Reference numeral 11 denotes a distributor for distributing a signal output from the signal generator 10. 12 (12-1 to 12-12) are phase shifters, and in order to obtain a uniform electric field distribution on the measured surface (also referred to as a test plane) of each radiation antenna, the phase of the electromagnetic wave radiated from each radiation antenna is measured. Is for adjusting the phase so that all are in phase on the surface to be measured. It is not necessary to adjust the length of the transmission line from the signal generator to the radiation antenna. Moreover, you may adjust the attachment position of a radiation antenna by moving back and forth with respect to the radiation direction of a radiation antenna. Reference numeral 18 denotes an output level adjuster, which is used to obtain a uniform electric field in the test plane. Level fluctuations caused by differences in propagation paths from the respective radiation antennas 5 (5-1 to 5-12) to the test plane, and equipment It is provided in order to absorb the variation in the electrical characteristics. In the present embodiment, an attenuator that attenuates a high-frequency signal is used. The attenuator is provided on the input side of the power amplifying device 13, but may be provided on the output side. Further, when the power amplifying device 13 has a function capable of adjusting its own amplification factor, the amplification factor may be adjusted. Reference numeral 13 (13-1 to 13-12) denotes a power amplifier. Reference numeral 14 (14-1 to 14-12) denotes a circulator. In this embodiment, a terminating resistor is not used, but may be connected as necessary. In this embodiment, a circulator is used, but an isolator may be used.

Next, the installation situation of the radiation antenna 5 in the present embodiment will be described. As shown in FIG. 3, antenna posts 4 a, 4 b, and 4 c are placed on the top of the gantry 6. Four radiating antennas 5 are installed on each of the columns, and a total of 12 (5-1 to 5-12) are used. In the present embodiment, the installation interval of the radiation antenna is set to 0.5 times or more the wavelength λ of the radiated electromagnetic wave. In addition, the gantry 6 can move freely on the floor surface of the anechoic chamber 7.

Next, the operation will be described. The sweep signal of 1 to 1.5 GHz generated by the signal generator 10 is distributed by the distributor 11 so as to have the same number as that of the radiating antenna 5, and the power is passed through each phase shifter 12 and the output level adjuster 18. Amplification is performed by an amplifying device 13 (in this embodiment, twelve 420W units are used). The amplified high-frequency signal is supplied to the radiating antenna 5 via the circulator 14 (in this embodiment, 12 Yagi / Uda type antennas having a gain of 8 dBi are used). The electromagnetic waves radiated from the radiating antennas (5-1 to 5-12) are synthesized in the space and are uniformly 600V on the test plane (φ30 cm in this embodiment) of the turntable 3 on which the EUT 2 is placed. / M electromagnetic field is generated.
At this time, the phase and amplitude are adjusted by the phase shifter 12 and the output level adjuster 18 already described in order to generate a uniform electromagnetic field on the test plane.
If it is necessary to change the test plane due to the size of the EUT 2 placed on the turntable 3 or the position of the test site, the gantry 6 on which the antenna support column is placed is operated. Thus, the radiation antenna 5 is moved so that electromagnetic waves can be radiated to the test plane.
In this embodiment, since the phase shifter 12 and the output level adjuster 18 are provided between the distributor 11 and the power amplifier 13, the withstand voltage of the phase shifter 12 and the output level adjuster 18 can be reduced. effective. However, when there is a margin in the withstand voltage, the present invention is not limited to this, and it may be provided anywhere on each distribution line of the distributor 11.
The circulator 14 reflects the electromagnetic wave radiated from the radiating antenna 5 at the metal part of the EUT and is received by the radiating antenna, and is applied to the power amplifying device 13 by the received power. This is to prevent the amplification device 13 from malfunctioning or failing.

Next, the required number of radiating antennas and how to obtain the antenna gain will be described.
First, according to the inventors, when the distance L between the EUT 2 and the radiating antenna is 1 m, a single antenna with a gain of 0 dB is used to achieve an electric field strength of 600 V / m on the test plane. It was found that about 30KW was required as the output of the machine. It was also found that the terminal voltage at this time was about 1200 V (50 ohms).

Therefore, in this embodiment, since 12 radiating antennas 5 are used in a stack, it was found that 2.8 KW can be adequately provided when they are combined in the same phase. In this case, the terminal voltage is about 370 V (50 ohms). Thus, by arranging the radiation antenna 5 on the stack and connecting the power amplification device 13 to each of them, the withstand voltage of the power amplification device 13 and the radiation antenna 5 can be lowered. Further, the withstand voltage can be further reduced by using a high gain antenna. For example, if an 8 dBi antenna is used, the power is 420 W and the withstand voltage is 150 V. If a 20 dBi antenna is used, the power is 28 W and the withstand voltage is 37 V.
Therefore, the type of radiation antenna, the required quantity, and the antenna gain may be appropriately selected according to the test frequency and the size of the EUT 2 (in other words, the size of the test plane).
In the above description, the distance L between the EUT 2 and the radiating antenna is 1 m, but it may be appropriately selected within a range of 1 to 3 m. Increasing the distance L increases the transmission loss in space, so it is necessary to increase the transmission power or change the antenna gain to a larger one. If the test plane is to be widened, the gain of the radiating antenna must be set low.

In the present embodiment, the output level adjuster 18 and the power amplifying device 13 have been described as separate housings, but may be mounted in one housing as described in claim 2. By comprising in this way, the electromagnetic wave generator which installation of an apparatus is easy and maintenance is easy can be provided.
FIG. 4 shows an example of a power amplifying apparatus 130 having a built-in output level adjuster 18.

It should be noted that the present invention is not limited to the above-described embodiment, and can be implemented by appropriately changing each part without departing from the spirit of the present invention, as exemplified below.
For example, in this embodiment, twelve radiation antennas and power amplifiers are used, but the number may be larger or smaller than this. Moreover, although 1-1.5 GHz was used as a test frequency in a present Example, it is not limited to this, If it is VHF band-SHF band, it can be used. In this case, an appropriate antenna (Yagi / Uda type antenna, helical antenna, electromagnetic horn) may be used according to the test frequency.

It is explanatory drawing of the disturbance exclusion capability test apparatus to which this invention is applied. It is a block diagram of an electromagnetic wave generator. It is explanatory drawing which shows the example of installation of a radiation antenna. It is a block diagram of the power amplifier of a different Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Interference exclusion capability test apparatus, 2 ... Test equipment, 3 ... Turntable, 4 ... Antenna support | pillar, 5 ... Radiation antenna, 6 ... Mount, 7 ... Anechoic chamber, 10 ... Signal generator, 11 ... Divider , 12 ... phase shifter, 13 ... power amplifier, 14 ... circulator, 15 ... transmitter, 17 ... electromagnetic wave generator, 18 ... output level adjuster, 19 ... control device, 130 ... power amplifier.

Claims (5)

In a device that generates electromagnetic waves,
A signal generator for generating high-frequency signals;
Multiple radiating antennas,
A distributor for distributing a signal output from the signal generator to the radiation antenna;
The same number of power amplifiers and output level adjusters as the plurality of radiation antennas;
An electromagnetic wave generator comprising: adjusting an output level with each of the output level adjusters so as to obtain a uniform electric field distribution on a test plane, and then radiating an electromagnetic wave from each corresponding radiation antenna.
The electromagnetic wave generator according to claim 1, wherein the output level adjuster and the power amplifying device are housed in a single casing.
The electromagnetic wave generator according to claim 1 or 2, wherein each radiation antenna is installed such that the radiation direction of the radiated electromagnetic wave is directed to the test equipment.
The radiating antenna is a Yagi-Uda antenna, a helical antenna, or an electromagnetic horn, and the frequency band of the radiated electromagnetic wave is a VHF band to an SHF band. Electromagnetic wave generator.
In the interference exclusion capability test equipment,
An anechoic chamber,
A signal generator for generating high-frequency signals;
Multiple radiating antennas,
A plurality of power amplifiers;
Multiple output level adjusters;
A turntable for mounting the EUT on one end of the anechoic chamber;
A stand for installing the radiation antenna at the other end of the anechoic chamber;
With
After adjusting the output level with each of the output level adjusters so as to obtain a uniform electric field distribution on the test plane, electromagnetic waves are radiated from the corresponding radiating antennas toward the EUT. Exclusion capability test device.

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