JP2014235131A - Simple device for testing strength for withstanding electromagnetic interference wave - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a simple device and a method for testing the strength for withstanding an electromagnetic interference wave capable of greatly shortening the time spent for immunity test.SOLUTION: The present invention comprises: a receiving antenna 101 for receiving an electromagnetic interference wave radiated from an electronic apparatus; a receiving unit 102 for receiving from the receiving antenna; a signal processing unit 103 for converting the time waveform of the received electromagnetic interference wave into a frequency spectrum and calculating an electric field intensity level; a storage unit 104 for storing the electromagnetic interference wave converted into the frequency spectrum; an arithmetic unit 105 for calculating, when electromagnetic interference waves each converted into a plurality of frequency spectra are accumulated in the storage unit, a difference between the electromagnetic interference waves; a comparison unit 106 for comparing the electric field intensity level with a threshold and extracting a frequency corresponding to the electric field intensity level exceeding the threshold; a display unit 108 for displaying the extracted frequency; a transmission unit 110 for generating a radio wave on the basis of a frequency, an application level, and an application time set by an application condition control unit 109; and a transmission antenna 111.

Description

  The present invention relates to an immunity test for evaluating a device's resistance to electromagnetic interference.

  With the progress of communication services and changes in the usage environment of electronic devices, electronic devices should not affect other devices with electromagnetic interference (emissions), and other devices or external electromagnetic interference There is a need for both immunity to electromagnetic interference that is not affected.

  The evaluation of the electromagnetic interference wave leaking from the electronic device is performed by observing the level of the electromagnetic interference wave using a measuring instrument such as a spectrum analyzer. In addition, the electromagnetic interference immunity test (immunity test) applies an electromagnetic wave simulating the electromagnetic interference received by the device to the electronic device in order to evaluate the resistance to the electromagnetic interference of the electronic device. This is done by observing (see Patent Document 1).

JP 2011-234189 A

  The immunity test method (IEC61000-4-3) has been established to prevent malfunctions caused by electromagnetic interference in communication equipment. In the conventional immunity test method, the frequency is changed for many electronic devices, and the immunity test is performed many times. Furthermore, since the test is performed in steps of 1% from 80 to 1000 MHz, there is a frequency where the immunity test is not performed even though it is easily affected by the interference wave because the tolerance level against the interference wave is low.

  Therefore, it is necessary to predict to some extent the frequency at which malfunction occurs. Further, with the recent increase in the frequency of electronic devices, immunity tests are required even at frequencies higher than 80 to 1000 MHz, and the time required for the tests needs to be shortened in order to perform an electromagnetic interference wave tolerance test in a wide band.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to significantly reduce the time required for the immunity test by using the result of the emission test that can be performed in a short time compared to the immunity test. There is.

  In order to achieve the above object, an electromagnetic interference wave proof test apparatus according to a first aspect of the present invention is a reception antenna that receives an electromagnetic interference wave radiated from an electronic device, and is connected to the reception antenna and received by the reception antenna. Connected to the signal processing unit that receives the electromagnetic interference wave from the receiving antenna, the signal processing unit that is connected to the reception unit, converts the time waveform of the received electromagnetic interference wave into a frequency spectrum, and calculates the electric field strength level A storage unit for temporarily accumulating electromagnetic interference waves converted to a frequency spectrum, the storage unit having a function of accumulating electromagnetic interference waves converted to a plurality of frequency spectra, and connected to the storage unit In the case where electromagnetic interference waves converted into a plurality of number spectra are stored in the storage unit, a calculation unit that takes a difference between the electromagnetic interference waves converted into a plurality of number spectra, and a calculation unit A comparison unit that compares the field strength level between the difference and a preset threshold value and extracts a frequency corresponding to the field strength level that exceeds the threshold value, and a display unit that is connected to the comparison unit and displays the extracted frequency And an application condition control unit that is connected to the comparison unit and sets the extracted frequency as a set frequency, and further sets an application level and an application time, and is connected to the application condition control unit and is set to a set frequency and an application level. The transmitter includes a transmitter that generates radio waves based on the application time, and a transmission antenna that is connected to the transmitter and radiates radio waves generated by the transmitter.

  The electromagnetic interference wave resistance simple test apparatus according to the second invention is the electromagnetic interference wave resistance simple test apparatus according to the first invention, wherein the reception antenna and the transmission antenna can both transmit and receive. A transmission / reception switching unit that is the same antenna, is connected to the same antenna, the reception unit and the transmission unit, and switches between the reception antenna and the transmission antenna of the same antenna; It is characterized by having.

  According to a third aspect of the present invention, there is provided a method for performing an electromagnetic interference proof test of an electronic device, the step of measuring the electromagnetic interference when the electronic device is stopped, and converting the measured electromagnetic interference when the electronic device is stopped into a frequency spectrum. Determining, storing the frequency spectrum when the electronic device is stopped in the storage unit, determining whether a plurality of frequency spectra are stored in the storage unit, and determining that the plurality of frequency spectra are not stored. Measuring the electromagnetic interference wave when the electronic device is operating, converting the measured electromagnetic interference wave when the electronic device is operating into a frequency spectrum, and storing the frequency spectrum when the electronic device is operating in the storage unit And calculating the difference between the frequency spectrum when the electronic device is stopped and the frequency spectrum when the electronic device is operating. A step of comparing with the threshold set in advance, a step of terminating the electromagnetic interference proof test when the difference is smaller than the threshold, and a step of extracting a frequency at which the difference is greater than or equal to the threshold when the difference is greater than or equal to the threshold; A step of setting an electromagnetic interference wave application time and an electromagnetic interference wave application level, an interference wave having an extracted frequency, a set electromagnetic interference wave application time, and a set electromagnetic interference wave application level is applied to an electronic device. And a step of performing.

  A method for performing an electromagnetic interference immunity test of an electronic device according to a fourth invention is a method of performing an electromagnetic interference proof test of an electronic device according to the third invention, comprising the step of measuring an electromagnetic interference wave. Before the step of measuring the electromagnetic interference and applying the interference to the antenna, the step of switching the function to measure the electromagnetic interference and the step of applying the interference toward the electronic device And a step of switching the function so as to apply a disturbing wave.

It is a block diagram which shows schematic calibration of the electromagnetic interference wave proof strength simple test apparatus concerning the 1st Embodiment of this invention. It is a flowchart which shows operation | movement of the electromagnetic interference wave proof test apparatus of this invention. It is a block diagram which shows schematic calibration of the electromagnetic interference wave proof strength simple test apparatus concerning the 2nd Embodiment of this invention.

  Of the electronic components such as the board inside the electronic device and the cable, the portion that radiates electromagnetic interference can be a portion that receives the electromagnetic interference due to the reversibility of the antenna. For this reason, it is considered that the immunity level is weak at the frequency at which electromagnetic interference waves are emitted. Based on this idea, an electromagnetic interference simple test apparatus and a method for performing an electromagnetic interference tolerance test according to the present invention are provided.

  Hereinafter, an electromagnetic interference simple test apparatus according to the present invention will be described with reference to the drawings.

<First Embodiment>
FIG. 1 shows a schematic configuration diagram of a simple electromagnetic interference wave resistance test apparatus to which the first embodiment of the present invention is applied. The electromagnetic interference wave resistance simple test apparatus of the present embodiment can perform an immunity test of an electronic device in a short time by using the measurement result of the radiation interference wave of the electronic device. The electromagnetic interference wave proof test apparatus shown in the figure includes a receiving antenna 101, a receiving unit 102, a processing unit 103, a storage unit 104, a calculation unit 105, a comparison unit 106, a threshold setting unit 107, and a display unit 108. And an application condition control unit 109, a transmission unit 110, and a transmission antenna 111.

  The receiving antenna 101 receives an electromagnetic interference wave when the electronic device to be measured is operating or when the electronic device is stopped. The processing unit 103 converts the time waveform of the received electromagnetic interference wave into a frequency spectrum by performing Fourier transform, and calculates the electric field intensity level. The storage unit 104 temporarily stores a plurality of signal processing results. The computing unit 105 obtains a difference between the electromagnetic interference wave stored when the electronic device is operating and the electromagnetic interference wave stored when the electronic device is stopped, and the electromagnetic wave generated from the electronic device without using the anechoic chamber. Measure the interference wave itself. The comparison unit 106 extracts a corresponding frequency when the electric field strength of the electromagnetic interference wave is higher than a set threshold value. The application condition control unit 109 sets an electromagnetic interference wave application time and an application level for each frequency when performing an electromagnetic interference wave tolerance test of an electronic device. The transmission unit 110 and the transmission antenna 111 apply to the electronic device an electromagnetic interference wave having an application time, an application level, and a frequency extracted by the comparison unit 106 set in the application condition control unit 109.

  FIG. 2 is a flowchart showing the operation of the electromagnetic interference wave proof test apparatus of the present invention. First, the electromagnetic interference wave when the electronic device is stopped is measured using the receiving antenna 101 and the receiving unit 102 (S1). The measured time waveform is converted into a frequency spectrum using Fourier transform or the like, and the converted data is stored in the storage unit 104 (S2). If two or more pieces of data are not stored in the storage unit 104 (S3: NO), the electromagnetic interference wave during operation of the electronic device is measured again using the receiving antenna 101 and the receiving unit 102. Similarly, after the time waveform when the electronic device is operating is converted into a frequency spectrum, the data is stored in the storage unit 104 (S3: YES), and the difference between the data when the electronic device is operating and the data when the electronic device is stopped is obtained (S4). ). If the electric field strength of the data after the calculation does not exceed the set threshold value (S5: NO), it is not necessary to perform the electromagnetic interference wave proof test for the corresponding frequency (S7). On the other hand, when the electric field strength of the data after the calculation exceeds the set threshold value (S5: YES), the corresponding frequency is extracted, and the application condition control unit 109 sets the electromagnetic interference wave application time and the application level. The electromagnetic interference wave tolerance test is performed by setting and applying the interference wave to the electronic device using the transmission antenna 111 (S6).

  In the electromagnetic interference proof strength simple test apparatus of the present embodiment described above, the electromagnetic interference immunity test is performed only on the frequency where the electric field strength of the electromagnetic interference generated from the electronic device is high. Time can be shortened. In addition, since a radiation interference wave is applied in a 1% step from 80 to 1000 MHz in a normal test, there are many frequencies that have not been confirmed for electromagnetic interference wave resistance. However, in the electromagnetic interference wave resistance simple test apparatus of the present embodiment, the test is performed not only on the frequency at which the electromagnetic interference wave is generated, that is, not only 80 to 1000 MHz but also the electromagnetic interference wave is measured. It is possible to carry out targeted electromagnetic interference immunity tests for frequencies that are susceptible to exposure.

  Furthermore, by taking the difference data between when the electronic device is operating and when the electronic device is stopped, it is possible to perform tests that are normally performed using an anechoic chamber without using the anechoic chamber and at a low cost. .

<Second Embodiment>
FIG. 3 is a schematic block diagram of an electromagnetic interference wave proof test apparatus to which the second embodiment of the present invention is applied. In the electromagnetic interference wave proof simple apparatus of the present embodiment, the reception antenna and the transmission antenna are realized by one antenna.

  In the illustrated electromagnetic interference wave resistance simple test apparatus, a transmission / reception switching unit 113 is attached to an antenna, whereby reception and transmission can be performed by one transmission / reception antenna 112.

101 reception antenna 102 reception unit 103 processing unit 104 storage unit 105 calculation unit 106 comparison unit 107 threshold setting unit 108 display unit 109 application condition control unit 110 transmission unit 111 transmission antenna 112 transmission / reception antenna 113 transmission / reception switching unit

Claims (4)

Electromagnetic interference wave resistance simple test device,
A receiving antenna for receiving electromagnetic interference radiated from an electronic device;
A receiving unit connected to the receiving antenna and receiving the electromagnetic interference wave received by the receiving antenna from the receiving antenna;
A signal processing unit that is connected to the receiving unit, converts a time waveform of the received electromagnetic interference wave into a frequency spectrum, and calculates a field strength level;
A storage unit that is connected to the signal processing unit and temporarily stores the electromagnetic interference wave converted into a frequency spectrum, and has a function of storing the electromagnetic interference wave converted into a plurality of the frequency spectrums. A storage unit;
When the electromagnetic interference wave converted to the plurality of the number spectrums is stored in the storage unit and connected to the storage unit, the difference between the plurality of the electromagnetic interference waves converted to the number spectrums is calculated. An arithmetic unit to take,
A comparison unit that is connected to the calculation unit, compares a field intensity level between the difference and a preset threshold value, and extracts a frequency corresponding to the field intensity level exceeding the threshold value;
A display unit connected to the comparison unit and displaying the extracted frequency;
An application condition control unit connected to the comparison unit, setting the extracted frequency as a set frequency, and further setting an application level and an application time;
A transmitter that is connected to the application condition controller and generates a radio wave based on a set frequency, an application level, and an application time;
An electromagnetic interference wave proof test apparatus characterized by comprising: a transmitting antenna that is connected to the transmitting unit and radiates the radio wave generated by the transmitting unit.   The reception antenna and the transmission antenna are the same antenna capable of both transmission and reception, and are connected to the same antenna, the reception unit and the transmission unit, and are the reception antennas of the same antenna. The electromagnetic interference wave resistance simple test apparatus according to claim 1, further comprising a transmission / reception switching unit configured to switch between the case of being a transmission antenna and the case of being a transmission antenna. A method for conducting an electromagnetic interference immunity test of electronic equipment,
Measuring electromagnetic interference when the electronic equipment is stopped;
Converting the measured electromagnetic interference wave when the electronic device is stopped into a frequency spectrum;
Storing the frequency spectrum when the electronic device is stopped in a storage unit;
Determining whether a plurality of the frequency spectra are stored in the storage unit;
When it is determined that the plurality of frequency spectra are not stored, measuring electromagnetic interference waves during operation of the electronic device; and
Converting the measured electromagnetic interference wave during operation of the electronic device into a frequency spectrum;
Storing the frequency spectrum during operation of the electronic device in a storage unit;
Taking the difference between the frequency spectrum when the electronic device is stopped and the frequency spectrum when the electronic device is operating;
Comparing the difference with a preset threshold;
When the difference is less than the threshold, terminating the electromagnetic interference immunity test;
Extracting the frequency at which the difference is greater than or equal to the threshold when the difference is greater than or equal to the threshold;
Setting the electromagnetic interference wave application time and electromagnetic interference wave application level;
Applying the interference wave having the extracted frequency, the set electromagnetic interference wave application time, and the set electromagnetic interference wave application level toward the electronic device. A method of conducting a wave strength test. Before the step of measuring electromagnetic interference, measuring the electromagnetic interference and switching the function of the antenna to which the interference is applied to measure the electromagnetic interference;
The electromagnetic interference according to claim 3, further comprising a step of switching the function of the antenna so as to apply the interference wave after the step of applying the interference wave toward the electronic device. A method of conducting a wave strength test.

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