JPH0330834B2 - - Google Patents

Description

[Detailed description of the invention] This invention is a radiation interference sensitivity test (hereinafter referred to as "RS test", RS is Radiated
The purpose of the present invention is to provide an RS test device that performs susceptability (abbreviation for susceptability), which is equipped with a function that can accurately and safely control the electric field strength of electromagnetic waves that are applied to the electronic equipment.

This type of RS test is one of the electromagnetic compatibility (hereinafter referred to as "EMC") tests, and tests the degree of resistance of electronic equipment under test to radio wave interference.

First, a conventional device of this type will be briefly explained using figures.

FIG. 1 is a configuration block diagram showing a conventional RS test device, in which 1 is a specimen, 2 is a transmitting antenna, 3 is a receiving antenna, and 4 is a memory for storing processing programs, measurement data, test conditions, etc. 5 is an input device that inputs information to the central processing unit; 6 is a central processing unit (hereinafter referred to as "CPU") that performs calculations and processing according to the processing program;
7 is a signal generator that generates a high frequency signal (hereinafter referred to as "RF signal") at a predetermined output level and frequency according to the control command of the CPU 6; 8 is connected to the signal generator 7 and outputs the RF signal; the level of
an attenuator adjusted according to control instructions of the CPU 6;
is an amplifier that amplifies the power of the RF signal whose level has been adjusted by the attenuator 8, and 10 is connected to the output terminal of the amplifier 9, and passes the power-amplified RF signal in only one direction and prevents reflection. RF with a non-reciprocal circuit (such as an isolator or circulator) that protects the
It is connected to the transmitting antenna 2 via a transmission line 16.

11 measures the intensity of the RF signal received by the receiving antenna 3 and inputs it via the RF transmission path 16 according to the control command of the CPU 6, and sends the intensity value to the CPU 6 via the interface bus cable 17. receiver, 1 is the above CPU6
An input/output interface 13 relays between the input device 5, signal generator 7, attenuator 8, receiver 11, display device and printing device 14; A display device (for example, a CRT display) for display, 14 a printing device for output printing and graphic plotting, 15 the above-mentioned specimen 1, a transmitting antenna 2, and a receiving antenna 3.
This is a shielding room that houses the transmitting antenna 2 and performs electromagnetic shielding to prevent radio waves radiated from the transmitting antenna 2 from leaking to the outside.

When attempting to bombard the specimen 1 with radio waves in such a configuration, first the transmitting antenna 2 and the receiving antenna 3 are faced to each other and set in a predetermined positional relationship, and then the electric field strength of the electromagnetic waves radiated from the transmitting antenna 2 is adjusted. Perform proofreading. This work is RS
The number of transmitting antennas 2 equal to the number of transmitting antennas 2 and receiving antennas 3 (usually 6 to 7 types) used in the frequency band to be tested (generally 10KHz to 40GHz)
The calibration is repeated while replacing the receiving antenna 3. The operation of the conventional apparatus in this calibration is as follows.

A processing program for carrying out the calibration is stored in the storage device 4, but when an operator inputs a command from the input device 5, the CPU 6 calls and imports the processing program, and then executes it.

A high frequency signal (hereinafter referred to as "RF signal") of a predetermined frequency and level is generated from the signal generator 7 according to the processing program.
) is input to an attenuator 8 to adjust the level, and then input to an amplifier 9 for amplification. The amplified RF signal is input to the transmitting antenna 2 via the irreversible circuit 10 and is radiated as a radio wave.

The electric field component of this radio wave is received by the receiving antenna 3, inputted to the receiver 11, and its intensity is measured. This radiated field strength value is converted into a digital signal within the receiver 11 and sent to the CPU 6 via the input/output interface 12. The processing program compares the radiation field strength value with a predetermined field strength standard and issues a command to the attenuator 8 to correct the error in order to make the two match, thereby adjusting the amount of attenuation.

The adjustment value of the amount of attenuation is stored in the storage device 4.

The above calibration process is repeated at predetermined frequency intervals in the frequency range of the transmitting antenna 2 and the receiving antenna 3, and after the calibration process is completed in the frequency range, the receiving antenna 3 is removed,
The settings are changed so that the transmitting antenna 2 is directed toward the specimen 1.

Next, in order to perform the RS test, the adjustment amount of the attenuator 8 obtained in the above-mentioned calibration process is read from the storage device 4, and while adjusting the attenuator 8 using the adjustment value corresponding to the predetermined frequency section. Similarly to the above, a radio wave having a predetermined radiated electric field strength is emitted from the transmitting antenna 2 and showered on the specimen 1.

In this way, the radiated electric field strength is controlled to a predetermined value in the frequency range of the transmitting antenna 2.

However, the above control of the radiation field strength has the following drawbacks.

That is, since the electric field calibration is performed with the transmitting antenna 2 and the receiving antenna 3 facing each other, it is unclear what the electric field around the specimen 1 is like, and furthermore, since the RS test is conducted in a shielded room,
There is a large fluctuation in the electric field distribution due to the resonance phenomenon that exists in this room. This electric field distribution is related to the indoor setting position and frequency of the transmitting antenna 2, so it is difficult to predict this variation.As long as the electric field calibration and electric field level control described above are performed, It is impossible to generate . When attempting to generate an electric field as high as 100 V/m, for example, the electric field level may be inappropriately controlled and reach an abnormally high electric field level, leading to destruction of the specimen 1. Furthermore, since the calibration is performed using the receiving antenna 3 that corresponds to the frequency range of the transmitting antenna 2, there is a drawback that the work is complicated and takes a long time.

The present invention solves the problems in the conventional RS test device and provides a safe and accurate RS test device.The present invention will be described in detail below with reference to the drawings.

Hereinafter, one embodiment of the present invention will be shown in FIGS. 2 to 7. FIG. 2 is a configuration diagram of an embodiment of the present invention, FIG. 3 is a configuration diagram of an electric field strength measuring device and an electric field sensor, and FIG. 4 is a flowchart showing the flow of processing.
Figure 5 is a signal system diagram showing measurement, control, and processing processing; Figure 6 is a diagram showing the relationship between electric field strength and control amount in the time domain; Figure 7 is a diagram showing the attenuator adjustment value and control in the frequency domain. It is a figure which shows the relationship with the final value of quantity.

In the figure, 1, 2, 4 to 10, and 12 to 17 are the same as in FIG. 18 is connected to the output terminal of the irreversible circuit 10 and takes out a part of the RF signal and sends it to an RF power meter 19
This is a coupler that outputs the main part of the RF signal to the transmitting antenna 2 side.

The RF power meter 19 measures the power of a part of the RF signal extracted by the coupler 18 according to the control command of the CPU 6, and introduces this measured value to the CPU 6 via the input/output interface 12. It is something.

20 is an electric field sensor that detects the electric field strength of radio waves radiated from the transmitting antenna 2; 21 is a fiber cable that electrically transmits optical signals between the electric field sensor 20 and the electric field strength measuring device 22;

This electric field strength measuring device 22 is the electric field sensor 2
The electric field detection signal obtained from
It is configured to be sent to CPU6.

FIG. 3 is a configuration diagram of an electric field strength measuring device and an electric field sensor, and in the figure, 23 is a fiber cable 21.
24 to 38 are the components of the electric field strength measuring device 22, and 24 is connected to the CPU 6 via the interface bus cable 17.
An interface circuit connected to the CPU 6 and relaying signals exchanged with the CPU 6; 25 a decoder that decodes instructions from the CPU 6; 26 a register that stores upper-level radiation field strength values; and 27 an error in the radiation field strength values. 28 is a light source that emits the light beam 29; 30 is a first lens that focuses the light beam 29; and 31 is a light splitter that distributes the light beam 29. , 32 is a second lens that focuses the light beam 29, 33 is a third lens that focuses the light beam 29, 34 is a first photoelectric conversion element on which the light beam 29 focused by the third lens 33 is incident, 35 36 is a reflecting mirror that reflects and focuses a part of the luminous flux 29 distributed by the optical distributor 31; 36 is a second photoelectric conversion element that receives the luminous flux 29 focused by the reflecting mirror 35; An error detection circuit 38 compares the electric signals of the first photoelectric conversion element 34 and the second photoelectric conversion element 36, and 38 is an interface circuit 2 that arranges electric field strength data stored in the register 26.
This is an encoder that sends data to 4.

Next, the operation of one embodiment of the present invention will be explained using FIGS. 2 to 7. At A in FIG. 4, the input device 5 connects the CPU via the input/output interface 12.
Enter the test conditions in step 6. This test condition requires RS
It includes the frequency range of the test, the required electric field strength and the frequency sweep step, the initial state of the process, the control boundary value, the number of repetitions in the sampling interval, the initial trial data and the initial setting data in the first optimization interval.

The initial settings of the signal generator 7, attenuator 8, RF power meter 19, and field strength measuring device 22 shown in B of FIG. This is done by sending a control command via No. 12.

At C in FIG. 4, the CPU 6 sends a drive command to the signal generator 7 to output a frequency corresponding to the first frequency sweep step in the frequency range of the RS test.

Furthermore, a drive command is sent from the CPU 6 to the attenuator 8 to set it to a predetermined amount of attenuation based on the initial trial data in the first optimization section.

Furthermore, a drive command is sent to the RF power meter 19 and the field strength measuring device 22 to set them in a ready state.

Measurement, control, and processing are performed at D in Figure 4.
This will be explained using FIGS. 6 and 7.

In Figure 5, in the measurement of RF power meter 19
The power of the power-amplified RF signal is measured, and the electric field sensor 20 and the electric field strength measuring device 2
2, the electric field strength near the specimen 1 of the radio waves radiated by the transmitting antenna 2 is measured. Looking at this operation in more detail, in FIG. 3, when the radio wave is incident on the dielectric 23 of the electric field sensor 20, the dielectric 23 generates heat due to dielectric loss. This heat is transferred to the fiber cable 21 buried in the dielectric 23.
and changes this optical transmission loss.

On the other hand, an interface circuit 2 connected to the CPU 6 by an interface bus cable 17
4 receives the control command from the CPU 6 and sends it to the decoder 25.
Here, the control command is decoded and sent to the register 26 and A/D conversion circuit 27.

Now, the luminous flux 29 emitted from the light source 28 is the first
The light beam 29 is focused by the lens 30 and enters the light splitter 31, where it is divided and a part of the light beam 29 travels straight and enters the fiber cable 21 via the second lens 32. This light beam 29 is transmitted through the fiber cable 21
Then, it passes through the electric field sensor 20 and returns to the electric field strength measuring device 22. and the third lens 33
The light enters the photoelectric conversion element 34, is focused, and enters the first photoelectric conversion element 34, where it is converted into a first electrical signal.

On the other hand, the other part of the previously distributed luminous flux 29 is rerouted and focused by the reflecting mirror 35 and enters the second photoelectric conversion element 36, where it is converted into a second electrical signal.

The first and second electrical signals are transmitted to the error detection circuit 37.
These differences are extracted and input to the A/D conversion circuit 27. Here, it is converted into a digital signal and held in the register 26.

Then, according to the instructions of the CPU 6, the encoder 38
CPU 6 via interface circuit 24
It is sent as a radiated field strength value.

Next, in FIG. 5, control is performed at J. Here, optimization control calculations are performed by the CPU 6 at K so that the radiation electric field intensity value matches the radiation electric field standard value, and as a result, a control amount is determined and this control amount is input to the process M.

In M, the CPU 6 sends a command to the attenuator 8 based on the control amount, and adjusts the amount of attenuation to adjust the radiated electric field strength of the radio waves radiated from the transmitting antenna 2.

Next, at I, the CPU 6 gives a command to the electric field sensor 20 and the electric field strength measuring device 22 to measure the radiated electric field strength. The radiation field strength value obtained as a result is sent to the CPU 6 via the interface bus 17 and the input/output interface.

Next, at L, state estimation and identification are performed by the CPU 6. State estimation is the process of measuring the state variable expressed as the vector sum of these disturbances and the control amount when a disturbance occurs, that is, a change in the amplification degree of the amplifier 9 or a change in the radiated electric field intensity due to resonance of the shielding chamber 15. be. Kalman filter theory can be used to estimate the state variables.

In addition, the identification of L means weighting the past control amount data, specifically the adjustment amount of the attenuator 8, in an exponential manner by calculation of the CPU 6 in estimating the state variable. The closer the control amount data is, the more important the state variable is estimated.

Next, in K, based on the state variables estimated in L,
The CPU 6 performs optimization control calculations as described above.

Note that the operation shown in J, that is, K and L, is within the sampling interval △, as shown in FIG.
The control amount Q changes every time T, and this operation is repeated by the CPU 6 to control the radiated electric field strength P so that it matches the radiated electric field standard value.

Next, in FIG. 4, at E, the CPU 6 determines whether or not the repetition of the sampling interval ΔT has ended, and if it has not, it moves to G, advances the sampling interval ΔT by one step, and executes D again.
When finished, move to H, advance frequency step △F in Fig. 7 by one step, and repeat C, D,
Repeat E, F, G.

By repeating the above operation over the entire frequency range of the RS test, the final value O of the control amount Q at the ΔT terminal and the adjustment amount N of the attenuator 8 are obtained, as shown in FIG. is controlled over the entire frequency range to meet predetermined radiated field strength standards.

The effect of this kind of action is,
First, since the radiated electric field intensity is detected by the electric field sensor 20 placed near the specimen 1, it is possible to accurately know the radiated electric field intensity of the radio waves bombarding the specimen 1 at all times.

Furthermore, the CPU 6 performs optimization control,
Fluctuations in the radiated electric field intensity due to the resonance of the shielding chamber 15 and fluctuations in the radiated electric field intensity due to variations in the amplification degree of the amplifier 9 can be minimized, making it possible to conduct accurate tests and ensure safety for the specimen 1. Tests can be conducted.

Furthermore, since the intensity of the radiated electric field can be detected using only one type of electric field sensor 20, there is no need to replace the receiving antenna 3 as in the conventional case, and labor saving and speeding up can be realized.

Next, another embodiment of the present invention will be described using FIG. 8.

FIG. 8 is a block diagram showing another embodiment of the present invention, in which numerals 1 to 22 are the same as in FIG. 1, and a coupler 18
The configuration is such that the RF power meter 19 is removed.
That is, excluding the coupler 8 and the RF power meter 19, the radiated field strength is set to a predetermined value only by the radiated field strength value of the radio wave detected by the electric field sensor 20. Even in such a configuration, the same effects as in the embodiment described above can be obtained.

Next, still another embodiment of the present invention will be described using FIG. 9.

FIG. 9 is a block diagram showing still another embodiment of the present invention, in which numerals 1 to 22 are the same as in FIG. 2, and a plurality of electric field sensors 20 are arranged in the shielding chamber 15.

In such a configuration, the electric field sensor 20 can detect the electric field distribution due to resonance within the shielding chamber 15, and thereby the electric field distribution causes fluctuations in the radiated electric field intensity of the radio waves bombarding the specimen 1. can be predicted more accurately.

In the above embodiment, each component was shown separated one by one, but several components may be combined into one to provide the functions of each of the components described above. Various modifications may be made without departing from the gist of the invention. Further, in another embodiment of the present invention shown in FIG. 8, similar effects can be obtained even when a plurality of electric field sensors are used.

Since the present invention is configured as described above, a radiation interference test can be performed accurately and safely.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing the configuration of a conventional radiation interference sensitivity test device, Fig. 2 is a block diagram of an embodiment of the device according to the present invention, and Fig. 3 is a block diagram showing the configuration of a conventional radiation interference sensitivity test device.
2 and a configuration diagram of the electric field sensor 20, FIG. 4 is a flowchart showing the flow of processing, FIG. 5 is a signal system diagram showing measurement, control, and processing processing, and FIG. 6 shows electric field strength and control amount in the time domain. FIG. 7 is a diagram showing the relationship between the adjustment amount of the attenuator 8 and the final value of the control amount in the frequency domain, FIG. 8 is a configuration diagram of another embodiment of the device according to the present invention, FIG. 9 is a block diagram of still another embodiment of the apparatus according to the present invention. In the figure, 1 is a specimen, 2 is a transmitting antenna, 3 is a receiving antenna, 4 is a storage device, 5 is an input device, 6 is a central processing unit, 7 is a signal generator, 8 is an attenuator, 9
is an amplifier, 10 is an irreversible circuit, 11 is a receiver, 1
2 is an input/output interface, 13 is a display device, 1
4 is a printing device, 15 is a shielded room, 16 is a high frequency transmission line, 17 is an interface bus cable, 18 is a coupler, 19 is a high frequency power meter, 20 is an electric field sensor, 21 is a fiber cable, and 22 is an electric field strength measuring device , 23 is a dielectric, 24 is an interface circuit, 25 is a decoder, 26 is a register, 27 is an A/D conversion circuit, 28 is a light source, 29 is a luminous flux, 30
31 is a first lens, 31 is a light distributor, 32 is a second lens, 33 is a third lens, 34 is a first photoelectric conversion element, 35 is a reflecting mirror, 36 is a second photoelectric conversion element, 37 38 is an error detection circuit, and 38 is an encoder. In the drawings, the same or corresponding parts are indicated by the same reference numerals.

Claims (1)

[Claims] 1. A signal generator that generates a high-frequency signal, an attenuator connected to the signal generator that adjusts the intensity of the high-frequency signal, and an attenuator that adjusts the intensity of the high-frequency signal that is connected to the attenuator. an amplifier for amplification; a non-reciprocal circuit connected to the amplifier and the output terminal to allow the amplified high-frequency signal to pass in only one direction; and a non-reciprocal circuit connected to the non-reciprocal circuit to radiate the amplified high-frequency signal as radio waves. A radiation interference sensitivity test device comprising a transmitting antenna and a means for receiving the radio waves radiated by the transmitting antenna and measuring the radiated electric field strength, the dielectric material absorbing the radio waves transmitted by the transmitting antenna and the dielectric An electric field sensor is configured with a fiber cable provided in the body and has a reciprocating path for light, and detects the intensity of the radiated electric field of the radio wave, and light is incident on the fiber cable provided in the electric field sensor, and the fiber cable is connected to the dielectric body. an electric field strength measuring device having a mechanism for measuring the heat generated when the radio waves are absorbed by the dielectric by detecting the intensity of the light that has passed through the dielectric, and obtaining a radiated electric field strength value of the radio waves; Information is exchanged between a storage device that stores programs, test conditions, etc. necessary for controlling the signal generator, attenuator, and electric field strength measuring device, and the electric field strength measuring device. A central processing unit that collects the radiated electric field strength values of the radio waves obtained from the radio waves, and performs predetermined processing and control to set the radiated electric field strength of the radio waves to a predetermined value based on the measured values, and test conditions etc. A radiation interference sensitivity testing device comprising: an input device for inputting to the central processing unit. 2. The device according to claim 1, wherein a plurality of the electric field sensors are provided, and the radiated electric field intensity is set to a predetermined value based on the radiated electric field intensity value of the radio waves obtained from these electric field sensors. Radiation interference sensitivity test equipment. 3. A signal generator that generates a high frequency signal, an attenuator connected to this signal generator that adjusts the intensity of the high frequency signal, an amplifier that is connected to this attenuator and amplifies the intensity adjusted high frequency signal, and a non-reciprocal circuit connected to the output end of the amplifier and allowing the amplified high-frequency signal to pass in only one direction; a transmitting antenna connected to the non-reciprocal circuit and radiating the amplified high-frequency signal as a radio wave; In a radiation interference sensitivity test device equipped with means for receiving radio waves radiated by a transmitting antenna and measuring the radiated electric field strength, the main part of the amplified high-frequency signal is connected to the output terminal of the amplifier and sent to the transmitting antenna. An output coupler, a high frequency power meter connected to the coupler and measuring the power of a part of the amplified high frequency signal, a dielectric body that absorbs the radio waves, and an optical an electric field sensor configured with a fiber cable having a reciprocating path and detecting the radiated electric field intensity of the radio wave; light is incident on the fiber cable provided in the electric field sensor, and the intensity of the light passing through the dielectric body is detected. An electric field strength measuring device having a mechanism for measuring heat generated when the radio wave is absorbed by the dielectric material and obtaining a radiated electric field strength value of the radio wave, the signal generator, and the attenuator. and a storage device that stores programs, test conditions, etc. necessary for controlling the electric field strength measurement device, and the signal generator that exchanges information between the storage device and the storage device;
The power value of the high frequency signal and the radiated field strength value of the radio wave obtained from the attenuator, the high frequency wattmeter, and the field strength measuring device are collected, and the radiated field strength of the radio wave is calculated based on these measured values. A radiation interference sensitivity testing device comprising: a central processing unit that performs predetermined processing and control to set a predetermined value; and an input device that inputs test conditions and the like to the central processing unit. 4. The device according to claim 3, wherein a plurality of the electric field sensors are provided, and the radiated electric field intensity is set to a predetermined value using the radiated electric field intensity value of the radio waves obtained from these electric field sensors. Radiation interference sensitivity test equipment.