JPH1048276A - Unit and system for informing electromagnetic interference - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inform presence of electromagnetic interference wave in a specified frequency band by extracting a specified frequency band from an electromagnetic interference wave and delivering an alarm based on a detection signal thereof when a set level is exceeded. SOLUTION: A frequency tuning circuit 2 extracts only a preset specified frequency component from an electromagnetic wave received by an antenna 1 and an electromagnetic wave detection circuit 3 detects the extracted component and converts it into a DC signal. That signal is compared with a preset level by a comparator 4 and an informing circuit 5 is operated when a set level is exceeded to inform an electromagnetic interference. The alarm is provided by sound, vibration, lighting of lamp, indication on an indicator or combination thereof. Since the unit responds only to a preset frequency, it does not respond to a strong electromagnetic wave of different frequency, e.g. a power line or lightning, when a frequency to which an electronic apparatus is susceptible, e.g. the frequency of radio wave for a portable communication unit, is set and a stabilized operation is attained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic interference reporting device and an electromagnetic interference reporting system for detecting and displaying the presence of electromagnetic noise, and belongs to the technical field of measuring electromagnetic waves.

[0002]

2. Description of the Related Art Conventionally, a device which issues an alarm when detecting an electromagnetic interference wave receives and detects an electromagnetic wave over a wide band, and outputs an acoustic output when the detected output exceeds a predetermined level. A device for turning on a lamp or displaying a level on a display or the like has been developed and is commercially available. The common features of these devices are that they do not detect electromagnetic interference waves in a very limited specific frequency band, and because they are intended to be used stand-alone, they can be connected to a communication cable and configured as a system. It is not.

[0003]

The above-described conventional electromagnetic interference detection apparatus receives and detects electromagnetic waves over a wide band, and cannot determine what frequency the electromagnetic interference waves are generated, and There is a problem that even if the generation of the electromagnetic interference wave can be detected, it cannot be recognized in a remote place.

The present invention has been made in view of the above circumstances, and detects the occurrence and presence of an electromagnetic interference wave in a specific frequency band, and detects that such an electromagnetic interference wave has been detected by a holding device. It is an object of the present invention to provide an electromagnetic interference notification device and an electromagnetic interference notification system that can be recognized not only by a person but also in a remote place.

[0005]

In order to achieve the above object, the present invention provides a means for extracting a specific frequency band from electromagnetic interference waves over a wide band, and a method for extracting an electromagnetic interference wave of the extracted specific frequency band. If the level exceeds a preset level, a means for outputting a detection signal, a means for issuing an alarm such as sound, vibration, lamp lighting, display of characters on a display, etc. by the detection signal to reduce electromagnetic interference of a specific frequency band. A device capable of detecting occurrence or presence can be configured.
Means for multiplexing and outputting an address signal and a detection signal of an electromagnetic interference wave to such a device, means for transmitting and receiving this output signal via a communication cable, decoding the content of the signal to be transmitted and received, and generating an alarm A system capable of recognizing the generation and presence of an electromagnetic interference wave at a remote location can be configured by the information management means for displaying the information.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows the basic configuration of the present invention. In FIG. 1, 1 is an antenna, 2 is a frequency tuning circuit, 3 is an electromagnetic wave detection circuit, 4 is a comparator, 5 is a reporting circuit,
Reference numeral 6 denotes a power supply of the notification device.

That is, from the electromagnetic wave received by the antenna 1, only a predetermined specific frequency component is extracted by the frequency tuning circuit 2, detected by the electromagnetic wave detection circuit 3, and converted into a DC level corresponding to the strength of the electromagnetic field. Is done. This DC level is compared with a preset level by the comparator 4, and if it exceeds the preset level, the notification circuit 5 operates to report an electromagnetic interference. In this case, the alarm display is performed by sound, vibration, lamp lighting, display of characters on a display, or a combination thereof.

[0008] The feature of the present notification device is that it responds only to a preset frequency.
Although the frequencies of power lines and lightning are different but do not respond to strong electromagnetic waves, stable operation can be expected.

[First Embodiment] FIG. 2 shows a first embodiment of the present invention. 2, 1 is an antenna, 2 is a frequency tuning circuit, 3 is an electromagnetic wave detection circuit, 4 is a comparator, 5 is a notification circuit, 6 is a power supply, 7 is an audio transmitter, 8 is a speaker, 9 is a diode, and 10 is a diode. 11 is a capacitor, 12 is a set level of the comparator 4, 13 is a vibration generator,
14 is a lamp lighting device, and 15 is a character display.

As the antenna 1, a printed antenna in which a dipole antenna or a loop antenna is formed using a printed circuit board is used. From the high frequency signal received by the antenna 1, only a specific frequency component is extracted by the frequency tuning circuit 2. Here, the frequency tuning circuit 2 uses a resonator using a strip line. The output of the frequency tuning circuit 2 is detected by a diode 9 and a resistor 10 and a capacitor 11
A low-frequency component is extracted by the low-pass filter composed of. Since the frequency component of the signal extracted from the low-pass filter is sufficiently wider than the switching frequency of the AM modulation wave or TDAM, the frequency component is usually about DC to 5 kHz. When this value exceeds a preset level 12 of the comparator 4, the comparator 4 operates and the output becomes high (hereinafter referred to as Hi). When the detection signal exceeds the set level 12, the comparator 4 keeps the state of Hi for a certain period of time even if the detection becomes lower than the set level 12. The holding time can be freely set, and is usually set to 1 to 10 seconds. However, the Hi state can be maintained until the reset switch is pressed. When the output of the comparator 4 becomes Hi, the audio transmitter 7 operates, and the audio signal is transmitted from the speaker 8 as an alarm sound.

When the comparator 4 operates, not only the audio transmitter 7 but also the vibration generator 13 and the lamp lighting device 1
4. The character display 15 also operates at the same time to generate an alarm.
In order to reduce the size of the notification device, it is of course possible to reduce some of the functions of the audio transmitter 7, the vibration generator 13, the lamp lighting device 14, and the character display 15.

Embodiment 2 FIG. 3 shows a second embodiment of the present invention, wherein 1 is an antenna, 2 is a frequency tuning circuit, 3 is an electromagnetic wave detection circuit, 4 is a comparator, and 5 is a message. The circuit, 16 is a filter, and 17 is a DC-DC converter.

As in the first embodiment, the interference wave received by the antenna 1 passes through the frequency tuning circuit 2 and passes through the electromagnetic wave detection circuit 3
Is converted to a DC level. In this embodiment, this DC
A part of the level is set to an appropriate voltage level using the DC-DC converter 17, and is used as a power source of the notification device.
The filter 16 is used to prevent noise of the DC-DC converter 17 from going to the comparator 4.

Usually, the strength of the electric field for sounding an alarm is as high as 1 V / m or more, and it is sufficiently possible to operate the notification device itself by using the energy.
However, since the voltage level is low, the voltage is raised to a voltage at which other electronic elements can operate with a DC-DC converter using a switched capacitor or the like.

[Embodiment 3] FIG. 4 shows a third embodiment of the present invention, wherein 1-1 is an antenna, 1-2 is an antenna placed at a position orthogonal to the antenna 1-1, 1-
3 is an antenna placed at a position orthogonal to the antennas 1-1 and 1-2, 2 is a frequency tuning circuit, 3 is an electromagnetic wave detection circuit,
4 is a comparator, 5 is a notification circuit, 6 is a power supply, and 18 is a power combiner.

The direction of the electromagnetic field vector changes depending on the surrounding environment. For example, in the vicinity of a metal body, the electric field is perpendicular to the metal surface. Therefore, in the disturbing wave reporting device in which the element is oriented in one direction, since the electric field intensity in only one direction can be measured, the intensity of the electric field intensity cannot be measured accurately. In the present embodiment, the influence of the change in the direction of the electric field vector is canceled by obtaining the magnitude of the electric field vector using three antennas arranged orthogonally to each other.

The electric fields received by the antennas 1-1 to 1-3 are converted into DC levels by the electromagnetic wave detection circuit 3 via the corresponding frequency tuning circuits 2. The relationship between the output of each electromagnetic wave detection circuit 3 and the electric field strength is determined by antennas 1-1 to 1-1.
Since -3 is placed in a direction orthogonal to each other, the components of the electric field vector Ex, Ey, if ^{Ez Vx = Ex 2 (1)} Vy = Ey 2 (2) Vz = Ez 2 and (3) Become.

The power combiner 18 by the three detection output sum taken if ^{Vx + Vy + Vz = Ex 2} + Ey 2 + Ez 2 = E 2 next to, the output corresponding to the magnitude of the electric field vector is obtained. By comparing this output level with a value set in advance by the comparator 4, it is possible to realize an interference wave reporting device that is not affected by the surrounding environment. The power combiner 18 can be easily realized by an operational amplifier or the like.

Fourth Embodiment FIG. 5 shows a fourth embodiment of the present invention, wherein 1 is an antenna, 2 is a frequency tuning circuit, 3 is an electromagnetic wave detection circuit, 4 is a comparator, and 5 is a message. The circuit, 6 is a power supply, and 19 is an ID signal generator.

That is, when an interference wave is generated and reaches a predetermined level, it is input through the antenna 1, the frequency tuning circuit 2 and the electromagnetic wave detection circuit 3, and the comparator 4 is turned on (O
N), and the alarm generator of the notification circuit 5 operates. An ID signal generator 19 is attached to the alarm generation unit of the notification circuit 5, and generates an ID of the interference wave notification device that has detected the interference wave. As a method of generating the ID, a method of identifying a reporting device by incorporating a plurality of sound sources and generating them in a specific combination by a switch incorporated in advance (for example, a sound source of 500 Hz to 2500 Hz every 100 Hz). If incorporated, the combination total of 2 ²¹ next, it is possible to identify about 200 thousands of notification apparatus) and,
There is a method of generating a digital signal by alternately generating sounds of different pitches to identify a notification device. This method can be easily realized by using a microprocessor and a ROM.

[Embodiment 5] FIG. 6 shows a fifth embodiment of the present invention, wherein 1 is an antenna, 5 is a notification circuit having an alarm generator, 6 is a power supply such as a battery, and 20 is A / D converter, 21 is a buffer memory, 22 is an arithmetic processing unit, 2
Reference numeral 3 denotes a spectrum comparison unit, and reference numeral 24 denotes a spectrum database.

The interfering wave received by the antenna 1 is converted into a digital signal by an A / D converter 20 using a sampling principle, and comprises a buffer memory 21, an arithmetic processing unit 22, a spectrum comparing unit 23, and a spectrum database 24. Is sent to the data processing unit. The data processing unit temporarily stores the waveform in the time domain in the buffer memory 21 and then converts the waveform into the frequency domain by the FFT of the arithmetic processing unit 22 or the like. By comparing the nature of the frequency spectrum with the spectrum data stored in the spectrum database 24 in advance by the spectrum comparing section 23, an alarm of the interfering wave is generated from the alarm generating section of the notification circuit 5.

The feature of this embodiment is that the monitoring frequency band is very wide. For example, sampling time 25
When an A / D converter of 0 ps is used, the frequency can be measured up to 1 / (2T) by the sampling theorem.
When the buffer memory 21 of the data processing unit is 1 kbyte, the cycle is 250 ns, and the period is 4 MHz to 4 MHz.
It is possible to monitor a very wide frequency band of 2 GHz.

[Embodiment 6] FIG. 7 shows a sixth embodiment. In FIG. 7, reference numeral 25 denotes an electromagnetic interference notification device;
Is a microphone that captures a sound signal generated by the electromagnetic interference notification device 25, 27 is a communication device, 28 is an information management device main body, 2
9 is an information display device, and 30 is a recording device.

When a strong electromagnetic field is generated near the electromagnetic interference notification device 25, the electromagnetic interference notification device 25 has, for example, the structure shown in Embodiment 4 and generates a specific combination of sound waves. This is picked up by, for example, a microphone 26 provided in each room. The audio signal picked up by the microphone 26 is converted into an electric signal and sent to the communication device 27. Communication device 27
Operates when a voice of a combination registered in advance is input to the microphone 26, and sends a signal to the information management device main body 28.
In the information management device main body 28, based on the transmitted signal,
The location where the alarm is generated and the owner of the electromagnetic interference notification device 25 are displayed on the display of the information display device 29 and are recorded on the recording device 30 at the same time. The communication device 27 can be easily realized by rewriting a program of a normal CPU-controlled communication device, and the information management device main body 28 can be easily created by creating a program on a workstation.

By using such a system,
Electromagnetic interference in large buildings such as hospitals can be centrally managed. As described above, according to the embodiment of the present invention, even if the presence of an electromagnetic interference wave can be detected conventionally, it was difficult to specify what caused the electromagnetic interference wave. Can solve the two points that the recognition of the existence of the electromagnetic interference wave is limited to the vicinity of the device that detects the electromagnetic interference wave. Since the embodiment of the present invention has such characteristics, for example, (1) A person who has embedded a sensitive device in the body holds the electromagnetic interference notification device according to the embodiment of the present invention. For example, in the case where a radio wave is emitted from a mobile phone in the vicinity of the user, the radio wave can be immediately notified to the person, so that it is possible to prevent a serious accident from occurring.

(2) The electromagnetic interference reporting device according to the embodiment of the present invention is incorporated in or installed in a device that is sensitive to a specific external electromagnetic interference wave, and the device has a resistance to the electromagnetic interference wave. If the electromagnetic interference notification device according to the embodiment of the present invention sets the level of an electromagnetic interference wave that outputs an alarm based on the value, a source of the electromagnetic interference wave is specified by issuing an alarm display, and a measure for keeping the electromagnetic interference wave away is provided. This is extremely effective in preventing malfunction of the device.

(3) In a room or space in which a device sensitive to a specific external electromagnetic interference wave is installed, it is necessary to manage the room or the entire space against intrusion of the electromagnetic interference wave. Even if there are many such rooms or spaces, by installing the electromagnetic interference notification system according to the embodiment of the present invention, the monitoring device does not reside in each room or space, and the control device It is possible to centrally monitor all the rooms or spaces in the place where is installed, and it is extremely effective in preventing malfunctions of equipment sensitive to specific external electromagnetic interference waves. And so on.

[0029]

As described above, according to the present invention, the occurrence or presence of an electromagnetic interference wave in a specific frequency band is detected, and the detection of such an electromagnetic interference wave is determined by the holder of the detection device. In addition, it is possible to provide an electromagnetic interference notification device and an electromagnetic interference notification system that can be recognized even in a remote place.

[Brief description of the drawings]

FIG. 1 is a configuration explanatory diagram showing an example of a basic configuration of the present invention.

FIG. 2 is a configuration explanatory view showing a first embodiment of the present invention.

FIG. 3 is a configuration explanatory view showing a second embodiment of the present invention.

FIG. 4 is a configuration explanatory view showing a third embodiment of the present invention.

FIG. 5 is a configuration explanatory view showing a fourth embodiment of the present invention.

FIG. 6 is a configuration explanatory view showing a fifth embodiment of the present invention.

FIG. 7 is a configuration explanatory view showing a sixth embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Antenna, 1-1 ... Antenna, 1-2 ... Antenna 1
Antenna placed at a position orthogonal to -1, 1-3 ... 1-
1, an antenna placed at a position orthogonal to 1-2, 2 ... frequency tuning circuit, 3 ... electromagnetic wave detection circuit, 4 ... comparator, 5 ...
Notification circuit, 6 ... Power supply of notification device, 7 ... Audio transmitter, 8 ... Speaker, 9 ... Diode, 10 ... Resistance, 11
... Condenser, 12 ... Comparator setting level, 13 ... Vibration generator, 14 ... Lamp lighting device, 15 ... Character display, 16
... Filter, 17 ... DC-DC converter, 18 ... Power combiner, 19 ... ID signal generator, 20 ... A / D converter,
21: buffer memory, 22: arithmetic processing unit, 23: spectrum comparison unit, 24: spectrum database,
25: an electromagnetic interference notifying device; 26, a microphone for capturing a sound signal generated by a notifying device; 27, a communication device; 28, an information management device main body; 29, an information display device;

Claims (6)

[Claims] An electromagnetic wave detection circuit for outputting a signal when an electromagnetic wave exceeding a predetermined level is detected in a predetermined frequency band, an output of the electromagnetic wave detection circuit as an input signal, And a circuit for indicating presence. 2. The electromagnetic interference notifying device according to claim 1, wherein the notifying device is operated by the detected energy. 3. The electromagnetic interference notifying device according to claim 1, wherein the antennas for detecting the electromagnetic waves are orthogonal to each other.
An electromagnetic interference reporting device, wherein two antennas are used, the energy of the electromagnetic field is determined from the levels detected by those antennas, and the energy level is used as a criterion for reporting. 4. The apparatus according to claim 1, wherein a waveform detected by the antenna is converted into a digital signal, and an arithmetic operation is performed on the signal to specify the type and level of the interference source and issue an alarm. Characteristic electromagnetic interference reporting system. 5. The electromagnetic interference notifying device according to claim 1, wherein an address circuit for setting an address of the device, a circuit for outputting a signal of the address circuit, an output signal of an electromagnetic wave detecting circuit, and an output of the address circuit. An electromagnetic interference reporting device, comprising: a circuit that multiplexes a signal; and an output terminal that outputs a signal of the multiplexing circuit. 6. An electromagnetic apparatus comprising: a plurality of the electromagnetic interference reporting devices according to claim 5; a communication cable connecting them; and an information management device for exchanging signals with the electromagnetic interference reporting device. Jamming notification system.