JP6784208B2 - Radiation interference wave measuring device and its judgment method - Google Patents

Description

The present invention relates to a radiated interfering wave measuring device and a method for determining the same.

Conventionally, in the so-called radiation interference wave test, which measures the radiation interference wave radiated from an electronic device or the like, the electric field strength of the radiation interference wave is measured for a certain period of time at the position where the electric field intensity of the radiation interference wave is maximized, and the electric field intensity is measured. It is confirmed whether or not the measured electric field strength is below the permissible value of the internationally established standard.

In this radiated interference wave test, since it is necessary to find the position where the electric field strength is maximum for each frequency in the frequency band of 30 to 1000 MHz, a so-called spectrum analyzer capable of measuring the spectrum in a wide band is used.

By the way, the spectrum analyzer measures the frequency spectrum while sweeping the frequencies that can be measured with a predetermined resolution bandwidth at predetermined time intervals (sampling time). Therefore, the spectrum analyzer has a problem that if a radiation interference wave is generated at a frequency other than the sampling frequency while sampling a certain frequency, the radiation interference wave cannot be captured.

That is, when the generation period of the radiated interference wave exceeds the sampling time of the spectrum analyzer, the capture rate of the radiated interference wave is less than 100%, so that the measurement point where the radiated interference wave can be captured and the radiated interference wave cannot be captured. There will be a measurement point. Therefore, the position where the maximum electric field strength can be obtained cannot be correctly selected from the electric field strength measured by the spectrum analyzer, and the correct test result cannot be obtained, so that a non-standard product may be overlooked. ..

In order to solve this problem, it is determined whether or not the electric field strength is accurately measured by determining the presence or absence of radiated interfering waves (hereinafter referred to as "intermittent noise") whose generation period exceeds the sampling time. A method has been proposed (see Patent Document 1). In the method described in Patent Document 1, the electric field strength is measured for each frequency sweep of the spectrum analyzer, and the presence or absence of intermittent noise is determined by analyzing the sampling timing and the level of the electric field strength.

Japanese Patent No. 4915050

However, in the method described in Patent Document 1, since the intermittent noise is measured by the sweep function of the spectrum analyzer, the capture rate of the intermittent noise is less than 100%. Therefore, even if the number of samplings is increased, the noise capture rate does not reach 100%, and there is a problem that intermittent noise is overlooked by analyzing the sampling timing and the level of the electric field strength.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a radiation interfering wave measuring device for reducing oversight of intermittent noise, and a method for determining the same.

One aspect of the present invention is a radiation interference wave measuring device for determining whether or not the electric field intensity distribution formed on the surface surrounding the radiation source of the radiation interference wave is correctly measured, and receives the radiation interference wave. The electric field strength distribution is measured by measuring the frequency spectrum of the electric field strength received by the antenna at a first residence time at a plurality of measurement points set on the antenna and a surface surrounding the radiation source. Of the measuring instrument 1 and the electric field strength distribution measured by the first measuring instrument, at a measuring point where a predetermined electric field strength at a predetermined frequency is obtained, the predetermined frequency received by the antenna The second measuring instrument that measures the electric field strength in real time for each second residence time, and the first measuring instrument that measures the electric field strength based on the electric field strength measured by the second measuring instrument. A control device for determining whether or not the electric field strength distribution has been measured correctly is provided, and the second residence time is set to the same value as the first residence time. It is a wave measuring device.

One aspect of the present invention is the above-mentioned radiation interference wave measuring device, wherein the control device has an electric field strength for each second residence time measured by the second measuring device and each for each second residence time. When the difference value from the average value of the electric field strength of the above exceeds a preset threshold number of times, it is determined that the electric field strength distribution measured by the first measuring instrument is not correctly measured.

One aspect of the present invention is the above-mentioned radiation interference wave measuring device, in which the predetermined electric field strength is the maximum electric field strength in the frequency spectrum of the electric field strength measured by the first measuring device. ..

One aspect of the present invention is the above-mentioned radiation interference wave measuring device, and the measurement point at which the predetermined electric field strength at the predetermined frequency is obtained is a position other than the null point of the radiation pattern of the radiation source. ..

One aspect of the present invention is the above-mentioned radiation interference wave measuring device, in which the frequency resolution bandwidth of the second measuring device is set to the same value as the frequency resolution bandwidth of the first measuring device. ..

One aspect of the present invention is the above-mentioned radiation interference wave measuring device, and the measuring method for measuring the electric field strength in real time in the second measuring device is a frequency spectrum of the electric field strength in the first measuring device. It is the same as the measurement method for measuring.

One aspect of the present invention is a radiation interference wave measuring device including an antenna for receiving radiation interference waves and determining whether or not the electric field intensity distribution formed on the surface surrounding the radiation source of the radiation interference waves is correctly measured. In the determination method, the electric field strength distribution is measured by measuring the frequency spectrum of the electric field strength received by the antenna with the first residence time at a plurality of measurement points set on the surface surrounding the radiation source. Of the first measurement step and the electric field strength distribution measured in the first measurement step, at the measurement point where the predetermined electric field strength at the predetermined frequency is obtained, the predetermined frequency received by the antenna The electric field strength is set to the second measurement step in which the electric field strength is measured in real time for each second residence time set to the same value as the first residence time, and the electric field strength measured in the second measurement step. Based on this, it is a determination method including a determination step of determining whether or not the frequency spectrum of the electric field strength measured in the first measurement step is correctly measured.

As described above, according to the present invention, it is possible to reduce oversight of intermittent noise.

It is a figure which shows an example of the schematic structure of the radiation interference wave measuring apparatus A which concerns on one Embodiment of this invention. It is a figure explaining the measurement principle of the 1st measuring instrument 4 which concerns on one Embodiment of this invention. It is a block diagram which shows the hardware structure of the control device 7 which concerns on one Embodiment of this invention. It is a figure explaining the relationship between the generation period of intermittent noise, and the first residence time. It is a flow chart of a series of operations of the position estimation method of the maximum electric field strength which concerns on one Embodiment of this invention. It is a figure which shows an example of the electric field strength distribution measured by the 1st measuring instrument 4 which concerns on one Embodiment of this invention. It is a figure explaining the method of the verification experiment which concerns on one Embodiment of this invention. The contour line which showed the electric field strength measured in the verification experiment which concerns on one Embodiment of this invention. It is a figure which shows the time waveform measured in the verification experiment which concerns on one Embodiment of this invention. The determination result of whether or not the electric field strength was accurately measured in the verification experiment according to the embodiment of the present invention and the determination method from step S114 to step S117 of the radiation interference device A according to the embodiment of the present invention. It is a figure which shows the characteristic table which summarized the determination result used for each residence time.

Hereinafter, the present invention will be described through embodiments of the invention, but the following embodiments do not limit the inventions claimed in the claims. Also, not all combinations of features described in the embodiments are essential to the means of solving the invention. In the drawings, the same or similar parts may be designated by the same reference numerals to omit duplicate explanations. In addition, the shape and size of elements in the drawings may be exaggerated for a clearer explanation.

Hereinafter, the radiation interference wave measuring device according to the embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a diagram showing an example of a schematic configuration of a radiation interference wave measuring device A according to an embodiment of the present invention. The radiation jamming wave measuring device A is, for example, a device used for a radiation jamming wave test for testing a radiation jamming wave emitted from a radiation source 100 which is a specimen according to an EMC standard. The radiated interference wave measuring device A is arranged in an anechoic chamber having a metal floor surface formed from a ground plane. The anechoic chamber is configured by attaching a radio wave absorber to the wall surface of the shield room excluding the metal floor. Here, the radiation source 100 is an electronic device or the like that emits a radiation interference wave.

As shown in FIG. 1, the radiation interference wave measuring device A includes a receiving antenna 1, an antenna mast 2, a turntable 3, a first measuring device 4, a second measuring device 5, a drive control unit 6, and a control device 7. To be equipped. The antenna mast 2, the turntable 3, and the drive control unit 6 constitute a position control mechanism.

The receiving antenna 1 is attached to the antenna mast 2 and is arranged at a position separated from the radiation source 100 by a predetermined distance. The receiving antenna 1 receives the radiated interfering wave radiated from the radiation source 100.

The antenna mast 2 supports the receiving antenna 1. The antenna mast 2 raises and lowers the receiving antenna 1 under the control of the drive control unit 6.
The turntable 3 is, for example, a disk-shaped turntable attached to a ground plane. The turntable 3 can rotate about an axis in the direction perpendicular to the ground plane under the control of the drive control unit 6. On the turntable 3, for example, the radiation source 100, which is a specimen, is placed via the table 200.

The first measuring instrument 4 is connected to the receiving antenna 1 via, for example, a communication cable.
The first measuring instrument 4 measures the frequency spectrum of the electric field strength received by the receiving antenna 1. As a result, the first measuring instrument 4 measures the electric field intensity distribution formed on the surface surrounding the radiation source 100.
Specifically, the first measuring instrument 4 measures the frequency spectrum of the electric field strength received by the receiving antenna 1 with the first residence time at a plurality of measuring points set on the surface surrounding the radiation source 100. To do. For example, the first measuring instrument 4 is a superheterodyne spectrum analyzer.

For example, as shown in FIG. 2, the first measuring instrument 4 measures the frequency spectrum while changing (sweeping) the frequency that can be measured with the resolution bandwidth 300 every predetermined sampling time. In this case, the first residence time is the sampling time at the above-mentioned predetermined frequency, which is the time obtained by dividing the sweep time by the number of sweep points. However, the first measuring instrument 4 of the present invention is not limited to the superheterodyne spectrum analyzer, and may be, for example, an FFT-based spectrum analyzer. In this case, the first residence time is the sampling time of the time waveform. The first measuring instrument 4 outputs the measured frequency spectrum to the control device 7.

The second measuring instrument 5 is connected to the receiving antenna 1 via, for example, a communication cable.
The second measuring instrument 5 measures the electric field strength received by the receiving antenna 1 in real time during a predetermined time (hereinafter, referred to as “monitoring time”). Specifically, the second measuring instrument 5 receives the electric field strength distribution measured by the first measuring instrument 4 by the receiving antenna 1 at a measurement point where a predetermined electric field strength at a predetermined frequency is obtained. The electric field strength of a predetermined frequency is measured in real time for each second residence time during the monitoring time. For example, the predetermined electric field strength is the maximum electric field strength in the electric field strength distribution measured by the first measuring instrument 4.

For example, the second measuring instrument 5 is a real-time spectrum analyzer, a spectrum analyzer set in Zero span mode, and an EMI receiver. However, the second measuring instrument 5 of the present invention is not particularly limited as long as it can measure the electric field strength seamlessly for each second residence time. However, the second residence time needs to be set to the same value as the first residence time.

The second measuring instrument 5 measures the electric field strength at a predetermined frequency for each second residence time, which is the same value as the first residence time, and outputs the measured electric field strength to the control device 7.

The drive control unit 6 is connected to each of the antenna mast 2 and the turntable 3 via a communication cable. Further, the drive control unit 6 is connected to the control device 7 via, for example, a communication cable.

The drive control unit 6 can change the relative position of the receiving antenna 1 with respect to the radiation source 100. The drive control unit 6 rotates the turntable 3 at predetermined angular intervals based on the control from the control device 7. Further, the drive control unit 6 raises or lowers the receiving antenna 1 at predetermined height intervals with the antenna mast 2 based on the control from the control device 7.

The control device 7 according to the embodiment of the present invention will be specifically described below.

As shown in FIG. 1, the control device 7 includes a control unit 71 and an arithmetic processing unit 72.

The control unit 71 controls the measurement of each of the first measuring instrument 4 and the second measuring instrument 5. Further, the control unit 71 controls the drive of the drive control unit 6.

The arithmetic processing unit 72 determines whether or not the electric field strength distribution measured by the first measuring instrument 4 is correctly measured based on the electric field strength for each second residence time measured by the second measuring instrument 5. judge.

Specifically, in the arithmetic processing unit 72, the difference value between the electric field strength for each second residence time and the average value of the electric field strength for each second residence time is set to a preset threshold value (hereinafter, “difference”). When it exceeds a predetermined number of times (hereinafter referred to as "number of times threshold value"), it is determined that the electric field strength distribution measured by the first measuring instrument 4 is not correctly measured.

FIG. 3 is a block diagram showing a hardware configuration of the control device 7 in FIG. The control device 7 includes a main control unit 801, an input device 802, an output device 803, a storage device 804, and a bus 806. The bus 806 connects the main control unit 801 and the input device 802, the output device 803, and the storage device 804 to each other.

The main control unit 801 includes a CPU (central processing unit) and a RAM (random access memory).
The input device 802 is used for inputting information necessary for the operation of the radiation interference wave measuring device A and instructing various operations.
The output device 803 is used to output (including display) various information related to the operation of the radiation interference wave measuring device A.

The storage device 804 is not limited in any form as long as it can store information, and is, for example, a hard disk device or an optical disk device. Further, the storage device 804 records information on a computer-readable recording medium 805, and reproduces the information from the recording medium 805.
The recording medium 805 is, for example, a hard disk or an optical disk. The recording medium 805 may be a recording medium on which a program for realizing the control unit 71 and the arithmetic processing unit 72 shown in FIG. 1 is recorded.

The main control unit 801 is adapted to exert the functions of the control unit 71 and the arithmetic processing unit 72 shown in FIG. 1 by executing, for example, a program recorded on the recording medium 805 of the storage device 804. The control unit 71 and the arithmetic processing unit 72 shown in FIG. 1 are not physically separate elements, but may be realized by software.

(Judgment principle)
Hereinafter, the determination principle for determining whether or not the electric field strength distribution measured by the first measuring instrument 4 is correctly measured in the arithmetic processing unit 72 will be described.
As shown in FIG. 4, in the height pattern 301 when the first residence time is shorter than the generation cycle of the intermittent noise, unlike the height pattern 302 when the first residence time is long, the electric field strength is lost. Will be done. Therefore, the electric field strength distribution obtained by measuring with the first measuring instrument 4 may not be accurately measured. Therefore, it is necessary to determine whether or not the electric field strength distribution measured by the first measuring instrument 4 is accurately measured.

Here, whether or not the electric field strength distribution is accurately measured by the first measuring instrument 4 may be determined by determining the presence or absence of intermittent noise. This intermittent noise is a radiation interference wave having a period longer than that of the first residence time in the first measuring instrument 4. Therefore, the presence or absence of intermittent noise can be determined by measuring the electric field strength seamlessly for each first residence time and determining whether or not the electric field strength obtained by the measurement fluctuates.

For example, when the first residence time is shorter than the generation cycle of the intermittent noise, the capture rate of the intermittent noise is less than 100%, so that the electric field strength fluctuates with time. On the other hand, when the first residence time is longer than the generation cycle of the intermittent noise, the capture rate of the intermittent noise is 100%, so that the electric field strength does not fluctuate with time.
Therefore, when the fluctuation of the electric field strength is large, that is, when the capture rate of the intermittent noise is not 100%, it can be determined that the intermittent noise exists. Therefore, the second measuring instrument 5 continuously measures the electric field strength for each second residence time, which is the same value as the first residence time, and determines whether or not the obtained electric field strength fluctuates. , It is possible to determine the presence or absence of intermittent noise.

At that time, the RBW (frequency resolution bandwidth) used in the second measuring instrument 5 capable of measuring the electric field strength in real time is the same as the RBW (RBW of the first measuring instrument 4) at the time of measuring the electric field strength distribution. By setting the value to, the frequency resolution becomes the same as that at the time of measuring the electric field strength distribution, and accurate judgment can be made. However, in the present invention, the RBW does not necessarily have to be the same value.

Further, since the detection method of the second measuring instrument 5 capable of measuring the electric field strength in real time has a different temporal response of each detection method, the electric field strength distribution is measured ((when measuring the first measuring instrument 4). ), The determination can be made accurately. However, in the present invention, it is not always necessary to match the detection methods. The detection methods include peak value detection, quasi-peak detection, and average. There is value detection etc.

Further, when the electric field strength is measured at the position of the null point of the radiation pattern of the radiation source 100, the intermittent noise cannot be measured even if the intermittent noise is generated. Therefore, in the measurement of the second measuring instrument 5, the measurement is performed at a position where the maximum electric field strength can be obtained. However, if the measurement position is not the null point of the radiation pattern, it does not have to be the position where the maximum electric field strength can be obtained in the measurement of the second measuring instrument 5.

Hereinafter, in the interference wave measuring device A according to the embodiment of the present invention, a series of operations of the position estimation method of the maximum electric field strength will be described with reference to FIG.

The operator inputs the measurement conditions in the position estimation method of the maximum electric field strength to the control device 7 (step S101).
The measurement conditions include, for example, the frequency band to be measured (measurement frequency band), the measurement range in the height direction (measurement range in the height direction), and the interval (height) between a plurality of measurement points set within the measurement range in the height direction. Interval), rotation angle range to be measured, interval between multiple measurement points set within the rotation angle range (angle interval), residence time (first residence time, second residence time), detection method, RBW, monitoring Time, difference threshold, number of times threshold, etc.

The control unit 71 sets the first residence time, detection method, and RBW of the first measuring instrument 4 to the first residence time, detection method, and RBW input by the operator in step S101 (step S102). ..

The control unit 71 controls the drive of the drive control unit 6 and moves the antenna mast 2 to the lower limit value of the measurement range in the height direction set in step S101. Further, the control unit 71 controls the drive of the drive control unit 6 to rotate the turntable 3 to the lower limit value of the rotation angle range set in step S101 (step S103).

The control unit 71 acquires the current height of the antenna mast 2 and the current angle of the turntable 3 from the drive control unit 6. Further, the control unit 71 starts the measurement of the first measuring instrument 4 and acquires the electric field strength measured by the first measuring instrument 4 (step S104). Then, the control unit 71 stores the acquired height of the current antenna mast 2, the current angle of the turntable 3, and the electric field strength measured by the first measuring instrument 4 in the storage device 804 in association with each other. Here, the electric field strength obtained in the first measuring instrument 4 is the electric field strength in the measurement frequency band at the measurement point represented by the current height of the antenna mast 2 and the current angle of the turntable 3.

The control unit 71 controls the drive of the drive control unit 6 and rotates the turntable 3 at the angular interval set in step S101 (step S105).

The control unit 71 acquires the current angle of the turntable 3 from the drive control unit 6, and outputs the acquired angle to the arithmetic processing unit 72. Then, the arithmetic processing unit 72 determines whether or not the current angle of the turntable 3 acquired from the control unit 71 is the upper limit value of the rotation angle range set in step S101 (step S106).

When the arithmetic processing unit 72 determines that the current angle of the turntable 3 acquired from the control unit 71 is the upper limit value of the rotation angle range, the calculation processing unit 72 proceeds to step S107. On the other hand, when the arithmetic processing unit 72 determines that the current angle of the turntable 3 acquired from the control unit 71 is not the upper limit value of the rotation angle range, the calculation processing unit 72 returns to step S104.

The control unit 71 controls the drive of the drive control unit 6 and raises the antenna mast 2 at the height interval set in step S101 (step S107).

The control unit 71 acquires the current height of the antenna mast 2 from the drive control unit 6, and outputs the acquired current height of the antenna mast 2 to the arithmetic processing unit 72. Then, the arithmetic processing unit 72 determines whether or not the current height of the antenna mast 2 acquired from the control unit 71 is the upper limit value of the height direction measurement range set in step S101 (step 108).

When the arithmetic processing unit 72 determines that the current height of the antenna mast 2 acquired from the control unit 71 is the upper limit value of the measurement range in the height direction, the calculation processing unit 72 proceeds to step S109. On the other hand, when the arithmetic processing unit 72 determines that the current height of the antenna mast 2 acquired from the control unit 71 is not the upper limit value of the measurement range in the height direction, the process returns to step S104.

As described above, when the processes from step S101 to step S108 are completed, the frequency spectrum of the electric field strength is measured at a plurality of measurement points by the first measuring instrument 4. That is, the radiation interference wave measuring device A changes the height of the receiving antenna 1 and the angle of the specimen (radiation source 100) in order to search for the position where the maximum electric field strength can be obtained, and the specimen as shown in FIG. It means that the electric field strength distribution 400 surrounding the above was measured.

Next, a method of determining whether or not the electric field strength distribution 400 measured by the first measuring instrument 4 is correctly measured will be described.
The operator selects a frequency for determining whether the electric field strength distribution 400 is correctly measured (hereinafter, referred to as “determination frequency”) (step S109). For the subsequent flows, processing is executed at this determination frequency. The determination frequency does not indicate a single frequency, but indicates a predetermined frequency band including the determination frequency.

The arithmetic processing unit 72 determines the height (antenna height) of the receiving antenna 1 and the turntable 3 from which the maximum electric field strength can be obtained from the electric field strength distribution measured in steps S103 to S108 stored in the storage device 804. The angle (turntable angle) is specified (step S110). The arithmetic processing unit 72 stores the identified antenna height and turntable angle at which the maximum electric field strength can be obtained in the storage device 804.

The control unit 71 controls the drive of the drive control unit 6 and moves the antenna mast 2 to the position of the antenna height specified in step S110. Further, the control unit 71 controls the drive of the drive control unit 6 and rotates the turntable 3 to the position of the turntable angle specified in step S110 (step S111).

The control unit 71 sets the second residence time, detection method, and RBW of the second measuring instrument 5 to be the same as the first residence time, detection method, and RBW set in the first measuring instrument 4 in step S102. (Step S112).

The control unit 71 starts the measurement of the second measuring instrument 5 and acquires the electric field strength measured by the second measuring instrument 5 (step S113). That is, the control unit 71 causes the second measuring instrument 5 to measure the electric field strength for each second residence time during the monitoring time set in step S101, and acquires the electric field strength measured by the second measuring instrument. .. The control unit 71 stores the electric field strength measured by the second measuring device 5 in the storage device 804.

The arithmetic processing unit 72 calculates an average value from the electric field strength for each second residence time measured in step S113. Then, the arithmetic processing unit 72 calculates the difference value between each electric field strength for each second residence time stored in the storage device 804 and the calculated average value, and stores the difference value in the storage device 804 (step S114). ).

The arithmetic processing unit 72 compares the difference value calculated in step S114 with the difference threshold value set in step S101 for each second residence time. That is, the arithmetic processing unit 72 determines whether or not the difference value exceeds the difference threshold value for each second residence time. Then, the arithmetic processing unit 72 determines whether or not the number of times the difference value exceeds the difference threshold value exceeds the number of times threshold value set in step S101 (step S115).

When the arithmetic processing unit 72 determines that the number of times the difference value for each second residence time exceeds the difference threshold value does not exceed the number of times threshold value, the electric field strength distribution measured in steps S103 to S108 is determined. It is determined that the measurement is correct (step S116). Then, the control unit 71 displays information indicating that the electric field strength distribution can be measured correctly on the display screen (not shown) of the control device 7.

On the other hand, when the arithmetic processing unit 72 determines that the number of times the difference value for each second residence time exceeds the difference threshold value exceeds the number of times threshold value, the electric field strength measured in steps S103 to S108. It is determined that the distribution has not been measured correctly (step S117). Then, the control unit 71 displays information indicating that the electric field strength distribution cannot be measured correctly on the display screen (not shown) of the control device 7.

When the above determination is performed at a plurality of determination frequencies, steps S109 to S117 may be repeated.

(Verification experiment)
Hereinafter, an experiment conducted for verifying the validity of the determination principle in the radiation interference wave measuring device A according to the embodiment of the present invention will be described with reference to FIGS. 7 to 10.

FIG. 7 is an explanatory diagram for explaining a method of a verification experiment according to an embodiment of the present invention.
The radiation source 500 to be measured used in the verification experiment is a biconical antenna 501 connected to a signal generator 502. The biconical antenna 501 is arranged at a height of 1.0 m. The signal generator 502 outputs a 100 MHz sine wave signal (hereinafter, referred to as “sine wave signal”) to the biconical antenna 501 every 90 ms.
The receiving antenna 1 is installed at a position 3 m away from the biconical antenna 501.

Under the experimental conditions as described above, the electric field strength distribution was measured by changing the first residence time of the first measuring instrument 4. In this verification experiment, the first residence time is 10 ms, 50 ms, which is shorter than the generation cycle of the sine wave signal output from the signal generator 502, 90 ms, which is the same as the generation cycle of the sine wave signal, and the generation of the sine wave signal. The electric field intensity distribution formed on the surface surrounding the radiation source 500 was measured by changing each of the four patterns of 200 ms, which is sufficiently longer than the period.

Then, the control device 7 measures the electric field strength distribution with the first measuring device 4, and then, in the electric field strength distribution, the receiving antenna 1 and the turn are located at the positions of the antenna height and the turntable angle where the maximum electric field strength can be obtained. The table 3 was moved, and the time waveform of the electric field strength was measured for 10 s (monitoring time = 10 s) for each second residence time using the second measuring instrument 5.

In this case, the second residence time of the second measuring instrument 5 was changed to 10 ms, 50 ms, 90 ms, and 200 ms in the same manner as in the electric field strength distribution measurement, and the electric field strength was measured. The detection method of No. 4 and the second measuring instrument 5 was the peak value detection. Hereinafter, since the first residence time and the second residence time have the same value, when each of the first residence time and the second residence time is not distinguished, it is simply referred to as "residence time".

FIG. 8 is a contour diagram showing the electric field strength measured in the verification experiment according to the embodiment of the present invention. The electric field strength distribution when the residence time is 10 ms (FIG. 8 (a)) and the electric field strength distribution when the residence time is 50 ms (FIG. 8 (b)) are the electric field strength distribution when the residence time is 200 ms (FIG. 8 (Fig. 8)). Compared with d)), the electric field strength distribution is disturbed, and it can be seen that the measurement is not accurate. On the other hand, the electric field strength distribution with a residence time of 90 ms (FIG. 8 (c)) shows the same distribution as the electric field strength distribution with a residence time of 200 ms (FIG. 8 (d)), and it can be measured accurately. I understand.

FIG. 9 is a diagram showing a time waveform measured in a verification experiment according to an embodiment of the present invention. The time waveform (FIG. 9 (a)) when the residence time is 10 ms and the time waveform (FIG. 9 (b)) when the residence time is 50 ms have a large fluctuation range, and the radiation interference wave device A according to the embodiment of the present invention. In the determination method from step S114 to step S117, if the determination is performed with the difference threshold set to +/- 2 dB and the number of times threshold value set to 3 times, it is determined that the electric field strength distribution cannot be measured accurately.

On the other hand, the time waveform when the residence time is 90 ms (FIG. 9 (c)) and the time waveform when the residence time is 200 ms (FIG. 9 (d)) have a small fluctuation range, and the electric field strength distribution can be measured accurately. Is determined.

FIG. 10 shows a determination result of whether or not the electric field strength was accurately measured in the verification experiment according to the embodiment of the present invention, and steps S114 to S117 of the radiation interference device A according to the embodiment of the present invention. It is a figure which shows the characteristic table which summarized the judgment result which used the judgment method of (1) for each residence time.

As shown in FIG. 10, when the residence time (first residence time) at the time of measuring the electric field strength distribution and the residence time (second residence time) at the time of measuring the time waveform are the same values, the respective determination results. It turns out that is always the same. That is, by monitoring the time variation of the electric field strength for each residence time same as that at the time of measuring the electric field strength distribution, it is possible to determine whether or not the electric field strength distribution can be measured accurately.

As described above, the radiation interference wave measuring device A measures the electric field strength distribution formed on the surface surrounding the radiation source with the first residence time, and then determines the electric field strength of the determination frequency at the maximum electric field strength. It is measured in real time for each second residence time, which is the same value as the residence time of. As a result, the radiated interference wave measuring device A can reduce the oversight of intermittent noise, and determines whether or not the electric field strength distribution has been accurately measured based on the electric field strength for each second residence time. be able to.

Although the embodiments of the present invention have been described in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and includes designs and the like within a range that does not deviate from the gist of the present invention.

In the above-described embodiment, the first measuring instrument 4 and the second measuring instrument 5 have been described as different measuring instruments, but the present invention is not limited thereto. That is, the first measuring instrument 4 and the second measuring instrument 5 may be the same measuring instrument.

(Additional note)
A radiation interference wave measuring device that determines whether the electric field strength distribution formed on the surface surrounding the radiation source has been measured correctly.
Equipped with an electric field measuring device and an arithmetic processing unit
The electric field measuring device is
An antenna that receives radiated interference waves and
The first measuring instrument that measures the frequency spectrum of the electric field strength received by the antenna, the second measuring instrument that measures the electric field strength received by the antenna in real time, and the relative position of the antenna with respect to the radiation source. Changeable position control mechanism and
It includes the antenna, the first measuring instrument, the second measuring instrument, and a control unit that controls the measurement of the electric field strength using the position control mechanism.
The control unit
Performing the first operation of setting the residence time of the first measuring instrument,
A second operation of setting a plurality of measurement points on the surface surrounding the radiation source is performed.
While controlling the position control mechanism, the antenna is used to perform a third operation of measuring the frequency spectrum of the electric field strength at the plurality of measurement points.
The arithmetic processing unit
The control unit executes a first arithmetic process for detecting the antenna height and the specimen angle at which the maximum electric field strength at a specific frequency is obtained from the electric field strengths of the plurality of measurement points measured in the third operation.
The fourth operation of moving the position control mechanism to the antenna height and the specimen angle at which the maximum electric field strength obtained by the first arithmetic processing is obtained is executed.
The fifth operation of setting the residence time of the second measuring instrument to be the same as the residence time set in the first operation is executed.
For a predetermined time, the sixth operation of measuring the electric field strength at a specific frequency is executed for each residence time set in the fifth operation.
The arithmetic processing unit
When the difference between the electric field strength of each residence time measured in the sixth operation and the average value of the electric field strength of each residence time measured in the sixth operation exceeds a predetermined threshold number of times. A radiation interference wave measuring device, characterized in that it executes a second arithmetic process for determining that the electric field strength at the plurality of measuring points measured in the second operation is not correctly measured.

A Radiation interference wave measuring device 1 Receiving antenna 2 Antenna mast 3 Turntable 4 First measuring device 5 Second measuring device 6 Drive control unit 7 Control device 71 Control unit 72 Arithmetic processing unit 100 Radiation source

Claims (7)

A radiation interference wave measuring device that determines whether or not the electric field intensity distribution formed on the surface surrounding the radiation source of radiation interference waves has been measured correctly.
An antenna that receives the radiated interference wave and
A first measurement for measuring the electric field strength distribution by measuring the frequency spectrum of the electric field strength received by the antenna with the first residence time at a plurality of measurement points set on the surface surrounding the radiation source. With a vessel
Of the electric field strength distribution measured by the first measuring instrument, the electric field strength of the predetermined frequency received by the antenna at the measurement point where the predetermined electric field strength at the predetermined frequency is obtained is the second. A second measuring instrument that measures in real time for each residence time of
A control device for determining whether or not the electric field strength distribution measured by the first measuring instrument is correctly measured based on the electric field strength measured by the second measuring instrument.
With
The radiation interference wave measuring device, wherein the second residence time is set to the same value as the first residence time. In the control device, a preset threshold value is obtained as a difference value between the electric field strength for each second residence time measured by the second measuring device and the average value of the electric field strength for each second residence time. The radiation interference wave measuring device according to claim 1, wherein when the number of times exceeds a predetermined number of times, it is determined that the electric field strength distribution measured by the first measuring device is not correctly measured. The radiation interference wave according to claim 1 or 2, wherein the predetermined electric field strength is the maximum electric field strength in the frequency spectrum of the electric field strength measured by the first measuring instrument. measuring device. The radiation interference according to claim 1 or 2, wherein the measurement point at which the predetermined electric field strength at the predetermined frequency is obtained is a position other than the null point of the radiation pattern of the radiation source. Wave measuring device. Any one of claims 1 to 4, wherein the frequency resolution bandwidth of the second measuring instrument is set to the same value as the frequency resolution bandwidth of the first measuring instrument. The radiated interfering wave measuring device according to. 1. The measuring method for measuring the electric field strength in real time in the second measuring instrument is the same as the measuring method for measuring the frequency spectrum of the electric field strength in the first measuring device. The radiated interference wave measuring device according to any one of claims 5. It is a determination method of a radiation interference wave measuring device equipped with an antenna for receiving radiation interference waves and determining whether or not the electric field intensity distribution formed on the surface surrounding the radiation source of the radiation interference waves is correctly measured.
With the first measurement step of measuring the electric field strength distribution for measuring the frequency spectrum of the electric field strength received by the antenna at the first residence time at a plurality of measurement points set on the surface surrounding the radiation source. ,
Among the electric field strength distributions measured in the first measurement step, the electric field strength of the predetermined frequency received by the antenna at the measurement point where the predetermined electric field strength at the predetermined frequency is obtained is the first. A second measurement step of measuring in real time for each second residence time set to the same value as the residence time of
A determination step for determining whether or not the frequency spectrum of the electric field strength measured in the first measurement step is correctly measured based on the electric field strength measured in the second measurement step.
Judgment method including.