JP2014045354A - Device and method for determining availability of wireless apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device and a method for determining whether or not a wireless apparatus is available on the periphery of an electric and/or electronic apparatus, by recording the frequency characteristics of electromagnetic noise discharged from an electric and/or electronic apparatus, and the frequency characteristics of radio waves utilized by the wireless apparatus, and then comparing them.SOLUTION: Frequency spectrum of electromagnetic noise A (target electromagnetic noise) radiated from an electric and/or electronic apparatus 10 is measured by a target electromagnetic noise detection unit 110, and the frequency spectrum of target electromagnetic noise thus detected is transmitted to a spectrum analysis unit 120. The frequency spectrum received by the spectrum analysis unit 120 is converted into target electromagnetic noise data, which is then recorded in a database unit 130. The target electromagnetic noise data is compared with reference frequency data, and availability of a wireless apparatus is determined based on presence or absence of a peak in the target electromagnetic noise at a reference frequency.

Description

  In the present invention, when a specific wireless device is used in the vicinity of an electric / electronic device, it is simply determined whether or not a radio wave emitted by the wireless device causes a malfunction due to electromagnetic interference to the electric / electronic device. The present invention relates to a wireless device availability determination apparatus and method.

  In places where electric and electronic devices such as communication facilities and hospitals are handled, the use of wireless devices is prohibited except for a part to prevent malfunction of electric and electronic devices due to electromagnetic interference. For this reason, conventionally, a method of evaluating the immunity against electric waves of electric / electronic devices and covering the electric / electronic devices with a shielding material so that the immunity level is higher than the radio wave strength of wireless devices (see Patent Document 1). ), Or a method of suppressing the radio wave output level of the wireless device used so that the radio wave strength of the wireless device is lower than the immunity level of the electrical / electronic device.

JP-A-7-131177

  However, in order to determine whether or not a wireless device can be used in this way, it is essential to know the immunity level of the electric / electronic device with respect to the radio waves. It was necessary to test whether the electrical and electronic equipment worked properly. And in order to confirm whether the countermeasures which were taken with respect to the electric / electronic device based on the test results are sufficient, the immunity test has to be performed again, and there is a problem that it takes time and cost.

  The present invention has been made in view of such problems, and the object of the present invention is to record the frequency characteristics of radiated electromagnetic noise emitted from electrical and electronic equipment and the frequency characteristics of radio waves used by wireless equipment. It is another object of the present invention to provide a wireless device availability determination apparatus and method for determining availability of a wireless device around an electric / electronic device by comparing them.

  In order to solve the above-described problem, the invention described in claim 1 is a wireless device availability determination device, wherein a storage unit in which a reference frequency band of a radio wave used by the wireless device is recorded, and a radio wave measurement antenna A reference frequency band of a radio wave used by a wireless device that determines whether or not it can be used is read from the storage device, and radiated electromagnetic noise radiated from an electric / electronic device in the read reference frequency band is read by the radio wave measurement antenna The target electromagnetic noise detection unit that measures and detects the frequency spectrum of the radiated electromagnetic noise, and the frequency spectrum of the radiated electromagnetic noise detected by the target electromagnetic noise detection unit, the peak of the target electromagnetic noise in the reference frequency band Based on the detection result of the presence or absence of the peak of the target electromagnetic noise in the reference frequency band, the spectrum analysis unit for detecting the presence or absence It said availability determination unit for determining availability of a line equipment, which further comprising a.

  According to a second aspect of the present invention, in the wireless device availability determination device according to the first aspect, the target electromagnetic noise detection unit is used by the wireless device set for each electric / electronic device to be measured. It is characterized by measuring radiated electromagnetic noise based on setting conditions related to frequency band, reference level, filter, and attenuator.

  According to a third aspect of the present invention, in the wireless device usability judging device according to the first aspect, the usability judging unit uses each band when the reference frequency band includes a plurality of discontinuous bands. It is characterized by determining whether or not it is possible.

  According to a fourth aspect of the present invention, in the wireless device availability determination device according to the first aspect, the reference frequency band is a frequency band from a lower limit frequency to an upper limit frequency of the occupied frequency band or the necessary frequency band. It is characterized by being.

  The invention according to claim 5 is a method for determining whether or not a wireless device can be used, and when the reference frequency band of the radio wave used by the wireless device is recorded in the storage device, the radio wave used by the wireless device that determines whether or not the radio device is used. Reading out the reference frequency band from the storage device, measuring the radiated electromagnetic noise radiated from the electric / electronic device in the read reference frequency band with a radio wave measuring antenna, and detecting the frequency spectrum of the radiated electromagnetic noise Detecting the presence or absence of a peak of the target electromagnetic noise in the reference frequency band from the detected frequency spectrum of the radiated electromagnetic noise, and based on the detection result of the presence or absence of the peak of the target electromagnetic noise in the reference frequency band And a step of determining whether or not to use the device.

  According to a sixth aspect of the present invention, in the method of determining availability of the wireless device according to the fifth aspect, the step of detecting the frequency spectrum of the radiated electromagnetic noise is set for each electric / electronic device to be measured. It is characterized in that radiated electromagnetic noise is measured based on setting conditions related to a reference frequency, a reference level, a filter, and an attenuator used by a wireless device.

  According to a seventh aspect of the present invention, in the method for determining whether or not the wireless device can be used according to the fifth aspect, in the method for determining whether or not the wireless device can be used, if the reference frequency includes a plurality of discontinuous bands, whether or not the wireless device can be used for each band It is characterized by distinguishing.

  According to an eighth aspect of the present invention, in the wireless device usability determination method according to the fifth aspect, the reference frequency band is a frequency band from a lower limit frequency to an upper limit frequency of the occupied frequency band or the necessary frequency band. It is characterized by being.

  Electromagnetic noise emitted from electrical and electronic equipment is regulated by laws and regulations, and measurement is always performed. Since the present invention can determine whether or not a wireless device can be used using this measurement result, it is not necessary to perform an immunity test for radio waves again, and the time and cost can be reduced.

It is a figure which shows the radio | wireless apparatus to be utilized in the circumference | surroundings of the electric / electronic device which should not be influenced by the electromagnetic noise from the outside, and an electric / electronic device. (A) is a figure which shows a frequency spectrum in case the peak of the radiated electromagnetic noise A of the electric / electronic device 10 exists in the frequency band of the radio wave B used by the wireless device 11, and (b) is an electric / electronic device. It is a figure which shows a frequency spectrum in case the peak of the radiation electromagnetic noise A of the apparatus 10 does not exist in the frequency band of the electromagnetic wave B which the radio | wireless apparatus 11 uses. It is a figure which shows the structure of the radio | wireless apparatus availability determination apparatus which concerns on one Embodiment of this invention. It is a flowchart which shows the detection procedure of the object electromagnetic noise which concerns on one Embodiment of this invention. It is a flowchart which shows the availability determination procedure of the radio | wireless apparatus which concerns on one Embodiment of this invention. (A) is a figure which shows setting conditions, (b) is a figure which shows object electromagnetic noise data, (c) is a figure which shows reference frequency data. (A) is a figure which shows the object electromagnetic noise data and reference frequency data which are compared, (b) is a figure which shows the overlap with the object electromagnetic noise data and reference frequency data to be compared.

  Hereinafter, embodiments of the present invention will be described in detail.

  FIG. 1 shows an electrical / electronic device 10 that should not be affected by external electromagnetic noise and a wireless device (such as a mobile phone or a wireless LAN) 11 that is desired to be used in the vicinity of the electrical / electronic device. Radiated electromagnetic noise A is radiated from the electrical / electronic device 10, and radio waves B used by the wireless device 11 are radiated from the wireless device 11.

  2A shows a frequency spectrum when the peak of the radiated electromagnetic noise A of the electric / electronic device 10 is in the frequency band of the radio wave B used by the wireless device 11, and FIG. The frequency spectrum when the peak of the radiated electromagnetic noise A of the electronic device 10 is not in the frequency band of the radio wave B used by the wireless device 11 is shown. The peak of the radiated electromagnetic noise A is higher than the noise floor (NF) by a predetermined level, for example, 6 dB or more, as shown in FIG. Therefore, as shown in FIG. 2B, when the radiated electromagnetic noise A is flat at the same level as the noise floor, it is assumed that there is no peak of the radiated electromagnetic noise A. 2 (a) and 2 (b) show only one frequency band of radio waves used by the wireless device 11, but when the wireless device 11 uses a plurality of frequency bands, respectively, The presence or absence of a peak of radiated electromagnetic noise A is determined in the frequency band.

  The radiated electromagnetic noise A from the electric / electronic device 10 is considered to be a combination of signals and clocks used for the operation of the electric / electronic device 10 or their harmonic components. Therefore, for example, when electromagnetic waves having the same frequency as the clock used for the operation of the electric / electronic device 10 enter from the outside, they interfere with each other and the clock of the electric / electronic device 10 cannot be received accurately. Therefore, when the frequency band of the radio wave B used by the wireless device 11 overlaps the frequency band of the radiated electromagnetic noise from the electrical / electronic device 10, it may be determined that the electrical / electronic device 10 may malfunction. it can.

  That is, when the radiated electromagnetic noise A of the electrical / electronic device 10 and the radio wave B used by the wireless device 11 overlap on the frequency axis, it is determined that the wireless device 11 cannot be used around the electrical / electronic device 10; If the radiated electromagnetic noise A of the electrical / electronic device 10 and the radio wave B used by the wireless device 11 do not overlap on the frequency axis, it is determined that the wireless device 11 can be used even around the electrical / electronic device 10.

  FIG. 3 shows a configuration of a wireless device availability determination apparatus according to an embodiment of the present invention. The wireless device availability determination device 100 includes a target electromagnetic noise detection unit 110, a radiated electromagnetic noise measurement antenna 111, a spectrum analysis unit 120, a database unit 130, an availability determination unit 140, a memory unit 150, a display unit 160, and an input unit 170. Consists of.

  The target electromagnetic noise detection unit 110 has a function of detecting the radiated electromagnetic noise A from the electrical / electronic device 10 received by the radiated electromagnetic noise measurement antenna 111 and transmitting the frequency spectrum thereof to the spectrum analyzing unit 120. Since this function can be realized by a generally known technique such as a superheterodyne method used in a measuring instrument such as a spectrum analyzer, the details are omitted.

  Here, a case where a spectrum analyzer is used as the target electromagnetic noise detection unit 110 will be described. However, a frequency spectrum may be obtained by Fourier transform from a waveform on a time axis using a measuring instrument such as an oscilloscope. When radiated electromagnetic noise A is detected by a measuring instrument such as a spectrum analyzer, it is necessary to set a frequency range, a reference level, a resolution bandwidth (RBW), a filter, an attenuator, and the like to be measured (see step 403 described later). .

  Furthermore, the target electromagnetic noise detection unit 110 determines the measurement conditions such as the frequency range, reference level, and RBW used by the wireless device 11 when measuring the electrical / electronic device 10 to be measured. It also has a function of recording in the database unit 130 every time, and the measurement can be simplified by calling from the database unit 130 as necessary.

  The spectrum analysis unit 120 has a function of converting the frequency spectrum received from the target electromagnetic noise detection unit 110 into “target electromagnetic noise data” and recording it in the database unit 130. The conversion method to “target electromagnetic noise data” will be described later.

  The database unit 130 has a function of recording the measurement conditions of the electric / electronic device from the target electromagnetic noise detection unit 110 and the “target electromagnetic noise data” of the electric / electronic device 10 from the spectrum analysis unit 120 for each type. Alternatively, it has a function of recording the frequency band of the radio wave used by the wireless device 11 as “reference frequency data” for each wireless communication method. These “reference frequency data” may be registered in advance in the database, or may be manually input by the user from the input unit 170 as necessary. The reference frequency is a frequency from the lower limit to the upper limit of the occupied frequency bandwidth or the necessary frequency bandwidth.

  Further, it has a function of transmitting “reference frequency data” to the availability determination unit 140 in accordance with a request from the availability determination unit 140. In addition, according to a request from the target electromagnetic noise detection unit 110, the measurement condition of the electric / electronic device 10 is transmitted to the target electromagnetic noise detection unit 110.

  The availability determination unit 140 reads the “target electromagnetic noise data” and the “reference frequency data” from the memory unit 150 or the database unit 130, and the frequency range of the “reference frequency data” with respect to the read “target electromagnetic noise data”. The presence / absence of an electromagnetic noise peak is detected, and if a peak exists, the wireless device 11 cannot be used, and if no peak is present, a determination result that the wireless device 11 can be used is transmitted to the display unit 170. Has the function of A method for detecting the presence or absence of an electromagnetic noise peak within the frequency range of the “reference frequency data” with respect to the “target electromagnetic noise data” and a method for determining whether or not the wireless device 11 can be used will be described later.

  The memory unit 150 has a function of temporarily recording each frequency spectrum when the spectrum analysis unit 120 converts the frequency spectrum from the target electromagnetic noise detection unit 110 into “target electromagnetic noise data”. Further, the availability determination unit 140 has a function for temporarily recording “target electromagnetic noise data” and “reference frequency data” read from the database unit 130.

  The display unit 160 has a function of displaying the determination result of the availability of the wireless device 11 from the availability determination unit 140, or displaying the operation status of the wireless device availability determination system 100.

  The input unit 170 has a function for inputting frequency band data used in various wireless communication methods as “reference frequency data” or a function for inputting various operation settings to the wireless device availability determination system 100. Have.

  FIG. 4 shows a target electromagnetic noise detection flow according to an embodiment of the present invention. First, the wireless device availability determination system 100 is turned on (step 401). The database unit 130 is searched for reference frequency data of the wireless device 11 that is being considered for use (step 402).

  When the reference frequency data is in the database unit 130, the database unit 130 is searched for setting conditions for measuring the electric / electronic device 10 to be measured (step 403). When there is no reference frequency data, the user inputs the frequency band of the radio wave used by the wireless device 11 from the input unit 170 to the database unit 130 as reference frequency data (step 404), and the input reference frequency data is shown in FIG. As shown in c), the data is recorded in the database unit 130 for each wireless communication method or each wireless device (step 405), and the process proceeds to step 403.

  When the database section 130 has setting conditions for measuring the electrical / electronic device 10 to be measured, that is, the frequency band, reference level, filter, attenuator, etc. (FIG. 6A) used by the wireless device 11 The setting condition is set in the target electromagnetic noise detection unit 110, and the antenna 111 is installed so as to be able to receive both horizontal polarization and vertical polarization, and the radiated electromagnetic noise A (target electromagnetic noise) of the electric / electronic device 10 is set. Is measured (step 408). When the database unit 130 does not have setting conditions for measuring the electric / electronic device 10 to be measured, the frequency band covering the reference frequency data is manually set in the target electromagnetic noise detection unit 110. However, if the frequency band is wide, it is divided and set within an appropriate range (step 407). The reference level, filter, attenuator, etc. are set manually (step 408), and RBW, VBW (video bandwidth), etc. are set manually (step 409). Then, it is determined whether the target electromagnetic noise of the electrical / electronic device 10 to be measured can be appropriately detected under the conditions set in steps 407 to 409 (step 410). If it is determined that the target electromagnetic noise can be appropriately detected, the setting condition is recorded in the database unit 130 (step 411), and the process proceeds to step 408. As a result of the measurement in step 408, the target electromagnetic noise detection unit 110 detects the target electromagnetic noise of the electrical / electronic device 10 to be measured (step 415).

  FIG. 5 shows a flow for determining whether or not a wireless device can be used according to an embodiment of the present invention. As shown in FIG. 4, target electromagnetic noise of the electrical / electronic device 10 to be measured is detected (step 501). The frequency spectrum of the target electromagnetic noise detected by the target electromagnetic noise detection unit 110 is transmitted to the spectrum analysis unit 120 (step 502). The frequency spectrum received by the spectrum analysis unit 120 is converted into target electromagnetic noise data (step 503), and the target electromagnetic noise data is recorded in the database unit 130 in a form as shown in FIG. 6B (step 504).

  As shown in FIG. 6, the target electromagnetic noise data is determined based on the reference frequency data of the wireless device that determines whether or not it can be used, and a peak that is 6 dB or more higher than the noise floor is detected within the frequency range. It is what. In addition, when it is desired that the wireless device 11 has a sufficient margin to prevent the electrical / electronic device 10 from being affected by malfunctions, the level detected as a peak should be 3 dB or more higher than the noise floor. You can also.

  Here, for example, when determining whether or not the wireless device 11 of the wireless system G can be used in the vicinity of the electrical / electronic device 10, the availability determination unit 140 sets the target from the database unit 130 as shown in FIG. The electromagnetic noise data and the reference frequency data are read and temporarily recorded in the memory unit 150 (step 505). Here, the wireless device 11 of the wireless system G is 1 to 10 kHz-30 kHz (5), 100 kHz-300 kHz (6), 100 MHz-120 MHz (7), 2.4 GHz-2.5 GHz (8) to 1 depending on the use environment. It is assumed that communication is performed by selecting a type of band. The availability determination unit 140 compares the target electromagnetic noise data temporarily recorded in the memory unit 150 with the reference frequency data, and determines whether there is a peak in the target electromagnetic noise data (step 506).

  When there is no peak, the display unit 160 displays that the wireless device can be used (step 507), and when there is a peak, the display unit 160 displays that the wireless device cannot be used (step 508). In the example illustrated in FIG. 7A, the wireless device 11 is determined to be unusable when the use frequency is 10 kHz-30 kHz (5), 2.4 GHz-2.5 GHz (8), and 100 kHz-300 kHz (6), 100 MHz- It is determined that it can be used at 120 MHz (7).

DESCRIPTION OF SYMBOLS 10 Electrical / electronic device 11 Wireless device 100 Wireless device availability determination device 110 Target electromagnetic noise detection unit 111 Antenna for measurement of radiated electromagnetic noise 120 Spectrum analysis unit 130 Database unit 140 Availability determination unit 150 Memory unit 160 Display unit 170 Input unit

Claims (8)

A storage unit in which a reference frequency band of radio waves used by wireless devices is recorded;
A reference frequency band of a radio wave that is provided with a radio wave measurement antenna and is used by a wireless device that determines whether it can be used or not is read from the storage device. A target electromagnetic noise detector that measures with a measurement antenna and detects a frequency spectrum of the radiated electromagnetic noise;
From the frequency spectrum of the radiated electromagnetic noise detected by the target electromagnetic noise detection unit, a spectrum analysis unit that detects the presence or absence of a peak of the target electromagnetic noise in the reference frequency band;
The availability determining unit that determines whether or not the wireless device can be used based on a detection result of the presence or absence of a peak of the target electromagnetic noise in the reference frequency band;
A device for determining whether or not a wireless device can be used.   The target electromagnetic noise detection unit measures radiated electromagnetic noise based on setting conditions related to a frequency band, a reference level, a filter, and an attenuator that are set for each electric / electronic device to be measured and used by the wireless device. The wireless device availability determination device according to claim 1.   2. The wireless device availability determination device according to claim 1, wherein, when the reference frequency includes a plurality of discontinuous bands, the availability determination unit determines availability for each band. 3.   2. The wireless device availability determination apparatus according to claim 1, wherein the reference frequency band is a frequency band from a lower limit frequency to an upper limit frequency of an occupied frequency band or a necessary frequency band. When the reference frequency band of the radio wave used by the wireless device is recorded in the storage device, the step of reading out the reference frequency band of the radio wave used by the wireless device that determines whether to use the device from the storage device;
Measuring the radiated electromagnetic noise radiated from the electric / electronic device in the read reference frequency band with a radio wave measuring antenna, and detecting the frequency spectrum of the radiated electromagnetic noise;
Detecting the presence or absence of the peak of the target electromagnetic noise in the reference frequency band from the detected frequency spectrum of the radiated electromagnetic noise;
Determining whether or not the wireless device can be used based on a detection result of presence or absence of a peak of the target electromagnetic noise in the reference frequency band;
A method for determining whether or not a wireless device can be used.   The step of detecting the frequency spectrum of the radiated electromagnetic noise includes radiating electromagnetic noise based on setting conditions relating to a frequency band, a reference level, a filter, and an attenuator that are set for each electric / electronic device to be measured and used by the wireless device. The wireless device availability determination method according to claim 5, wherein measurement is performed.   6. The wireless device availability determination method according to claim 5, wherein the availability determination step determines availability of use for each band when the reference frequency includes a plurality of discontinuous bands.   6. The wireless device availability determination method according to claim 5, wherein the reference frequency band is a frequency band from a lower limit frequency to an upper limit frequency of the occupied frequency band or the necessary frequency band.

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