JP2001324524A - Automatic measuring method and device for undesired radiation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an automatic measuring method and device for undesired radiation capable of lightening a load to an operator by automatically measuring the undesired radiation (EMI) from an EUT (a device to be measured). SOLUTION: The EUT is put on a turn table 1, and made rotatable at a desirable angle with a turntable controller 3. The height of an antenna 2 is made optionally adjustable with an antenna controller 4. The turntable controller 3 and the antenna controller 4 are controlled with a personal computer(PC) 6. By this system constitution, the angle of the EUT at which the EMI intensity becomes maximum and the height of the antenna 2 are automatically adjusted, and the undesired radiation (EMI) is automatically measured with a spectrum analyzer 5 in plural frequency ranges.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for automatically measuring unnecessary radiation, and more particularly to a method and apparatus for automatically measuring unnecessary radiation or electromagnetic interference (EMI) radiated from a device under test (EUT) such as various electronic equipment or electronic equipment. The present invention relates to a method and an apparatus for measuring the temperature.

[0002]

2. Description of the Related Art Many devices use electronic circuits (electronics) for control and other purposes. In particular,
Advances in semiconductor integrated circuit (IC) technology, including microprocessors (MPU), have resulted in higher performance of various electronic applied devices, and various electronic devices have been used in offices or homes in close proximity to each other. ing. Some of these electronic devices operate at very high speeds with extremely low power levels. Therefore, EM radiation from other electronic devices
I causes noise in other adjacent electronic devices, which may cause a malfunction or may be destroyed in some cases. Accordingly, regulations on EMI by the FCC (US Federal Communications Commission) and other regulatory agencies have been increasingly tightened. Therefore, how to reduce EMI is an important development subject for electronic devices and electronic applied devices, and at the same time, there is a need to accurately and easily measure such EMI.

A conventional technique for measuring such unnecessary radiation is disclosed in, for example, "Electromagnetic Environment Observing Apparatus" of Japanese Patent Application Laid-Open No. 9-218230. In this publication, the electromagnetic environment is observed, the quality of communication is estimated from the observation results, and an electromagnetic environment observation device capable of classifying the electromagnetic environment at the observation place and a radiation source of unnecessary radiation are specified. And a small and lightweight electromagnetic environment observation device are disclosed. According to such a conventional technique, when measuring the unnecessary radiation, an operator (measurer) sticks to the spectrum analyzer to measure the EUT.
In order to find the worst state of the intensity level of EMI (electromagnetic interference) emitted from the (measured device), a simple operation was repeated in the same posture for a long time.

[0004]

However, according to the prior art as described above, there are some problems to be solved as follows. First, since the operation is performed for a long time in the same posture, the pain or burden on the operator is great. Second, the worst state (level) of the EMI intensity cannot be accurately determined unless the operator is a certain skillful operator. In other words, E
Training an operator to measure MI requires sufficient education and is time-consuming and expensive. Third, a long operation by the operator is required, which may cause a measurement error.

[0005]

OBJECTS OF THE INVENTION It is therefore an object of the present invention to provide a method and an apparatus for automatic measurement of unwanted radiation which can overcome or ameliorate the above-mentioned problems of the prior art.

[0006]

SUMMARY OF THE INVENTION According to the present invention, there is provided a method for automatically measuring unwanted radiation, which comprises measuring unwanted radiation (EMI) over a wide frequency range from an EUT using a spectrum analyzer. The antenna is arranged facing the EUT, and the turntable is rotated to adjust the angle with respect to the antenna and the antenna height based on control signals from a computer, respectively. And record the data obtained. According to the preferred embodiment, the frequency range of the spectrum analyzer is divided into a plurality of frequency ranges in advance, and unnecessary radiation is measured for each frequency range. The height of the antenna is sequentially moved from the lowermost or uppermost initial position. The spectrum analyzer measures in the quasi-leading value detection mode.

Further, the automatic measurement apparatus for unnecessary radiation of the present invention comprises a turntable on which an EUT is mounted, an antenna arranged at a fixed distance from the turntable, and an EMI intensity received from the EUT from the EUT. A turntable controller for adjusting the rotation angle of the turntable, an antenna controller for adjusting the height of the antenna, and a turntable controller for adjusting the rotation angle of the turntable. , An antenna controller and a computer for controlling the measuring device. According to a preferred embodiment example,
The maximum EMI value measured by the measuring instrument, the angle of the turntable and the height data of the antenna are stored in the memory of the computer. In addition, a printer is connected to the computer, and data stored in the memory of the computer is printed out.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The construction and operation of a preferred embodiment of the method and apparatus for automatically measuring unwanted radiation according to the present invention will be described below in detail with reference to the accompanying drawings.

First, the method and apparatus for automatically measuring unwanted radiation (EMI) according to the present invention is based on the EUT of the device under test (EUT).
Once the MI intensity has been determined from the initial measurement without operator intervention, the angle (orientation) of the EUT, the positioning of the antenna height to sense the EMI intensity, and the worst case are determined, the frequency and the EMI intensity detection are all determined. It is performed automatically.

FIG. 1 is a system configuration diagram of a preferred embodiment of an EMI automatic measuring device according to the present invention. This EMI
The automatic measuring device is a turntable 1 on which the EUT is placed,
An antenna 2, a turntable controller 3, an antenna controller 4, a spectrum analyzer (which is an EMI intensity measuring device in a frequency spectrum unit, hereinafter referred to as a spectrum analyzer) 5, a personal computer (computer) 6, and a printer 7, which are arranged at a fixed distance from the antenna. , Monitor 8 and Q-PEAK detector 9.

Next, the function of each component described above will be described. The turntable 1 has the EUT mounted thereon and the antenna 2
, That is, the direction is changed. This is because the EMI emission of the EUT depends on the direction,
This is for knowing the I radiation direction. The antenna 2 detects the EMI intensity radiated from the EUT. The controllers 3 and 4 control the angle of the turntable 1 and the height of the antenna 2 respectively. The spectrumr 5 analyzes the EMI intensity signal from the antenna 2. The personal computer 6 controls the rotation of the turntable 1, the positioning of the antenna 2, and the spectrum analyzer 5. The monitor 8 provides an interface between the personal computer 6 and an operator. The printer 7 prints out data and the like as the measurement results. Q-Peak (quasi-leading value) detector 9
Performs the intended EMI measurement in cooperation with the spectrumr 5.

Next, the operation of the automatic EMI measuring apparatus shown in FIG. 1 will be described with reference to the flowchart of FIG. Normal,
Figure 1 shows how to measure EMI radiation.
The system configuration is as shown in FIG. When measuring the EMI, the operator manually adjusts the rotation of the turntable 1 and the height position of the antenna 2 to find the radiation intensity level from the EUT. When the rotation direction of the turntable 1 and the height position of the antenna 2 are determined, the frequency range of the spectrum analyzer 5 is narrowed. Further, the same operation is performed again, thereby finally determining the direction of the turntable 1 and the height position of the antenna 2. Thereafter, the EMI intensity is measured by quasi-leading value detection (hereinafter referred to as Q-Peak).

The automatic EMI measuring apparatus and method according to the present invention is characterized in that all manual measurements through a conventional operator are automatically performed. Hereinafter, the operation will be described. First, a frequency range to be measured by the spectrum analyzer 5 is input (step S1). According to EMI standard, 30MHz
From 1 GHz to 1 GHz. If measurement is performed at a time in such a wide frequency range by the spectrum analyzer 5, there is a possibility that measurement omission (missing) may occur.
Therefore, the frequency range is divided into a plurality of (for example, 4) blocks for measurement.

Next, the polarization of the antenna 2 is determined. This is determined first because there is only horizontal or vertical polarization (step S2). Further, the user inputs the height of the antenna 2 (step S3). Next, the number of measurements is input (step S4). In the initial measurement, the antenna 2 is set, for example, at the lowermost position or the uppermost initial position. Next, the mode of the spectrum analyzer 5 is set to the peak hold (step S5). In the case of regular application data based on the EMI standard, measurement is performed at the near-leading value. The quasi-lead value does not exceed the peak value in principle, and the peak hold measurement is performed in this peak hold mode because the measurement time is faster than the quasi-lead value. The above steps S1 to S5 are preparations before the EMI of the EUT is measured.

Next, EMI actually radiated from the EUT
The noise measurement is started (Step S6). First, the height of the antenna 2 is switched, for example, and the measurement is performed at the lowest position (step S7). Further, the frequency range is switched (step S8). In this state, the turntable 1 is rotated (step S9), and data of the rotation direction angle with the largest noise in the rotation direction of the turntable 1 is detected (step S10). Since the rotation angle is controlled by the controller 3 of the turntable 1, the data from the turntable controller 3 can be stored as data on the PC 6 by downloading the data from the GPIB (general-purpose measurement interface bus) or the like. . The EMI intensity, frequency and angle data of the turntable 1 based on this measurement are stored in a memory (not shown) (step S19).

Next, the worst level frequency range is expanded (step S11). Then, the angle of the turntable 1 is adjusted (step S12). Next, the measured EM
It is determined whether or not I is at the maximum level (step S13). If it is not the maximum level (step S13: NO), the process returns to step S12, and the angle of the turntable 1 is adjusted. If it is at the maximum level (step S13: YES), the height of the antenna 2 is adjusted (step S14).
Further, it is determined whether or not this is the maximum level (step S1).
5). If not the maximum level (step S15: NO)
Return to step S14 described above, and
Is adjusted until maximum EMI is obtained. In the case of the maximum level (step S15: YES), the quasi-leading value measurement is performed (step S16). Then, step S16
Is stored in the memory (step S17). Finally, it is determined whether or not all the mode measurements have been completed (step S18). If the measurement in all modes has not been completed (step S18: NO), the process returns to step S7 and repeats steps S7 to S18. When all mode measurements have been completed (step S18:
If (YES), the measurement ends.

With the above steps, the worst frequency in the EMI intensity can be measured. By performing the above operation in the second worst state, the third worst state, and so on, predetermined EMI data can be measured.

The configuration and operation of the preferred embodiment of the EMI automatic measurement method and apparatus according to the present invention have been described above in detail. However, it should be understood that such exemplary embodiments are merely examples of the present invention and do not limit the present invention in any way.

[0019]

As will be understood from the above description, the following practicable effects can be obtained by the EMI automatic measuring method and apparatus of the present invention. First, since existing systems or equipment are used, large-scale hardware investment is not required. Second, since the measurement is automatically performed without the intervention of an operator, the burden on the operator and operation errors (human error) by the operator can be reduced or eliminated.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram of a preferred embodiment of an automatic measurement apparatus for unnecessary radiation according to the present invention.

FIG. 2 is a flowchart showing a method for automatically measuring unwanted radiation according to the present invention using the system configuration shown in FIG. 1;

[Explanation of symbols]

 Reference Signs List 1 turntable 2 antenna 3 turntable controller 4 antenna controller 5 spectrum analyzer (spectral analyzer or measuring instrument) 6 personal computer (computer) 7 printer 8 monitor 9 quasi-leading value (Q-Peak) detector

Claims (7)

[Claims] 1. A method for measuring unwanted radiation from a device under test (EUT) over a wide frequency range using a spectrum analyzer, comprising: placing the EUT on a turntable; and placing an antenna facing the EUT. Arrange, rotate the turntable, adjust the angle to the antenna and the height of the antenna based on control signals from a computer, respectively, and obtain the data obtained by obtaining the maximum unnecessary radiation intensity position by the spectrum analyzer. An automatic measurement method of unnecessary radiation, characterized by recording. 2. The frequency range of the spectrum analyzer is divided into a plurality of frequency ranges in advance, and unnecessary radiation is measured for each frequency range.
Automatic measurement method of unnecessary radiation described in 4. 3. The apparatus for automatically measuring unnecessary radiation according to claim 1, wherein the height of the antenna is sequentially moved from a lowermost position or an uppermost position. 4. The method for automatically measuring unwanted radiation according to claim 1, wherein said spectrum analyzer measures in a quasi-leading value detection mode. 5. A turntable on which a device under test (EUT) is mounted, an antenna disposed at a fixed distance from the turntable, and an unnecessary radiation (EMI) intensity from the EUT received by the antenna is measured. A measurement device for measuring the EMI intensity from the EUT, a turntable controller for adjusting a rotation angle of the turntable, an antenna controller for adjusting a height of the antenna, An automatic measurement apparatus for unnecessary radiation, comprising a turntable controller, a computer for controlling the antenna controller and the measuring device. 6. A maximum EMI value measured by the measuring device,
The apparatus of claim 5, wherein the angle data of the turntable and the height data of the antenna are stored in a memory of the computer. 7. The apparatus for automatically measuring unnecessary radiation according to claim 6, wherein a printer is connected to the computer, and data stored in a memory of the computer is printed out.