KR20060087118A - Apparatus for warning magnetic field derangement using the terrestrial magnetism sensor - Google Patents

Abstract

The present invention uses the phenomenon that the earth magnetic field is disturbed by the electromagnetic wave of the electronic product, an alarm is generated when a magnetic field of a certain intensity or more is detected so that the user can effectively suppress exposure to harmful electromagnetic waves. A magnetic field alarm device, comprising: an X-axis and a Y-axis magnetic field detection device detecting an X-axis and a Y-axis magnetic field by driving control of a sensor driving circuit enabled by a CS (Chip Selection) signal; First and second magnetic field amplifiers each amplifying the detected values of the Y-axis magnetic field detection device; digitally converting the amplified values of the first and second magnetic field amplifiers, and using the values to obtain angle = arctan (Y value / X value) It includes magnetic field strength calculation and alarm control block that outputs alarm signal by comparing the reference value with the intensity of magnetic field through the distance between X value and Y value from the center value. It is sex.

Geomagnetic sensor, magnetic field alarm

Description

Apparatus for warning magnetic field derangement using the terrestrial magnetism sensor}

1 is a configuration diagram of an abnormal magnetic field alarm device according to the present invention

2 is a flow chart showing a process for measuring the strength of the geomagnetic field for the abnormal magnetic field alarm

3A and 3B are graphs showing the magnetic field strength and the output of the geomagnetic sensor when measuring the geomagnetic intensity

Figure 4 is a graph of the X, Y axis when performing the algorithm for obtaining the magnetic field strength according to the present invention

Explanation of symbols for main parts of the drawings

11. Sensor drive circuit 12a.12b. 1,2 magnetic field amplifier

13. Magnetic field strength calculation and alarm control block 14. Geomagnetic sensor

15. X-axis magnetic field detection device 16. Y-axis magnetic field detection device

The present invention uses the phenomenon that the earth's magnetic field is disturbed due to the electromagnetic wave of the electronic product, an alarm is generated when a magnetic field of a certain intensity or more is detected, so that the user can effectively suppress exposure to harmful electromagnetic waves. It relates to a magnetic field alarm device.

With the recent surge in the use of electronic and electrical devices, there is a growing concern and concern about the damage caused by electromagnetic waves emitted from these devices.

In particular, there is an increasing concern about the effects of electromagnetic waves emitted from mobile communication terminals which are used in contact with the human body. In this regard, for apparatuses used in close contact with a human body such as a mobile communication terminal, a national institution or an international organization prescribes a specific absorption rate (SAR) of the human body.

The human body absorption rate (SAR) of electromagnetic waves is a figure indicating how much electromagnetic waves generated by devices such as mobile communication terminals are absorbed by the human body. When using a mobile communication terminal, it refers to a numerical value expressed in terms of the amount of electromagnetic waves per unit mass of the biological tissue absorbed by the biological tissue.

Until now, electromagnetic wave blocking products including electromagnetic wave shielding materials have been developed and marketed to block harmful electromagnetic waves generated from electronic products. Also, in order to avoid the risk of the electromagnetic waves, the so-called avoidance that reduces the use time of products that generate a lot of electromagnetic waves ( Countermeasures such as Prudent Avoidance are emerging.

However, even when such a method is applied, it is practically difficult to block or avoid this in the case of a device that is used very much in everyday life such as a mobile communication terminal.

In the conventional mobile communication terminal, the earth magnetic field measuring device is applied, but this is used for the purpose of informing the correct direction and is not used to block or avoid the electromagnetic waves.

The present invention is to solve the problem of the electromagnetic wave blocking or avoiding method in the conventional mobile communication terminal as described above, when a magnetic field of a certain intensity or more is detected by using the phenomenon that the earth magnetic field is disturbed by the electromagnetic wave of the electronic product. It is an object of the present invention to provide an abnormal magnetic field alarm device using a geomagnetic sensor that can effectively suppress exposure to harmful electromagnetic waves by generating an alarm.

Abnormal magnetic field alarm device using a geomagnetic sensor according to the present invention for achieving the above object is to detect the X-axis, Y-axis magnetic field by the drive control of the sensor drive circuit enabled by the CS (Chip Selection) signal Axis and Y-axis magnetic field detection device; First and second magnetic field amplifiers for amplifying the detection values of the X-axis magnetic field detection device and the Y-axis magnetic field detection device, respectively; Digitally converts the amplified values of the first and second magnetic field amplifiers Magnetic field strength calculation and alarm control block that calculates the intensity of the magnetic field through the distance between X value and Y value from the center value and compares it with the reference value by using angle = arctan (Y value / X value). And characterized in that the configuration.

Here, the magnetic field strength calculation and alarm control block is characterized in that the alarm is generated so that the user can know that the magnetic field of a predetermined intensity or more is entered when the obtained magnetic field strength value has a value other than 250 ~ 300mG.

In addition, the alarm output from the magnetic field strength calculation and the alarm control block is preferably output in different forms step by step according to the strength value of the magnetic field obtained by using the color or sound.

Other objects, features and advantages of the present invention will become apparent from the following detailed description of the embodiments.

Preferred embodiments of the abnormal magnetic field alarm device using the geomagnetic sensor according to the present invention will be described in detail with reference to the accompanying drawings.

1 is a configuration diagram of an abnormal magnetic field alarm device according to the present invention.

Various communication devices and home appliances that are closely used in daily life emit electromagnetic waves harmful to the human body. To solve this problem, the present invention utilizes a phenomenon in which the earth's magnetic field is disturbed due to electromagnetic waves of electronic products. When a magnetic field of more than a certain intensity is entered, an alarm is generated to prevent the user from being exposed to more than a certain amount of electromagnetic waves.

That is, by detecting the magnetic field strength of the geomagnetic sensor that is applied to determine the direction in the mobile communication terminal, it is possible to know the degree to which the electromagnetic waves from the electronic product disturb the earth magnetic field.

The abnormal magnetic field alarm device according to the present invention is a magnetic field strength calculation and alarm control block that controls the support sensor 14 and the geomagnetic sensor 14 and converts the analog output value of the geomagnetic sensor 14 into a digital value. 13) is composed largely.

The abnormal magnetic field alarm device according to the present invention is enabled by a CS (Chip Selection) signal, as shown in Figure 1, the sensor drive circuit 11 for controlling the drive of the geomagnetic sensor 14 for the detection of the X, Y axis magnetic field ), An X-axis magnetic field detection device 15 for detecting the X-axis magnetic field by the drive control of the sensor drive circuit 11, and a Y-axis magnetic field for detecting the Y-axis magnetic field by the drive control of the sensor drive circuit 11. The first magnetic field amplifier 12a for amplifying the detection value of the detection device 16, the X-axis magnetic field detection device 15, and the second magnetic field amplifier 12b for amplifying the detection value of the Y-axis magnetic field detection device 16. ), And digitally convert the amplified values of the first and second magnetic field amplifiers 12a and 12b, and use the values to calculate angle = arctan (Y value / X value), and the distance between the X value and the Y value from the center value. When the intensity of the magnetic field is obtained and the user is exposed by comparing with the reference value, the magnetic field of dangerous intensity is entered. If it is determined to include a magnetic field strength calculation and alarm control block 13 for outputting an alarm signal is configured.

The abnormal magnetic field alarm device according to the present invention is to determine the reference value after applying a certain magnetic field strength through the calibration equipment to measure the strength of the magnetic field, and to inform the user if it has a value other than 250 ~ 300mG.

When enable / disable is set as the CS (Chip Selection) signal and the X and Y axes are selected, a voltage value indicating the magnitude of the magnetic field emitted through the X and Y axis magnetic field detection devices 15 and 16 is obtained. After amplifying through the first and second magnetic field amplifiers 12a and 12b, the signals are output as analog voltages through the output terminals of the X-axis output and the Y-axis.

The magnetic field strength calculation and the digital conversion using the ADC (Anlog to Digital Convertor) of the alarm control block (13) are obtained as angle = arctan (Y value / X value), and the distance between the X value and the Y value from the center value is obtained. Find the strength of the magnetic field.

Here, the X-axis selection, Y-axis selection, X-axis output, Y-axis output terminals of the magnetic field strength calculation and alarm control block 13 may be implemented with a single PIN according to the implementation of the geomagnetic sensor.

The process for applying a certain magnetic field strength through the calibration equipment and the process of obtaining the magnetic field strength using the output of the geomagnetic sensor will be described as follows.

2 is a flow chart showing a process for measuring the strength of the geomagnetic field for the abnormal magnetic field alarm, Figures 3a and 3b is a graph showing the output of the magnetic field strength and geomagnetic sensor when measuring the geomagnetic intensity.

First, the measurement process for obtaining the analog values of the outputs VXmax, VXmin, VYmax, and Vymin is as follows.

Measurement (Calibration) Measures the magnetic field inside the equipment (S201) And the reverse magnetic field is applied to offset the magnetic field inside the measuring equipment (S202).

And the magnetic field is generated as in Figure 3a. 3A shows the strength of the magnetic field during measurement. (S203)

As shown in FIG. 3B, the output value from the geomagnetic sensor is converted into an ADC value and then stored.

The magnetic field strength is calculated by using Avxmax, Avxmin, Avymax, and Avymin, which convert analog values of outputs VXmax, VXmin, VYmax, and Vymin obtained from the measurement step into digital values.

4 is a graph of the X and Y axes when the algorithm is performed to obtain the magnetic field strength according to the present invention.

In fact, when the ADC converted value of the X- and Y-axis output values of the geomagnetic sensor is x and y, the magnetic field strength is calculated. The magnetic field of + 1G and -1G is applied to the X and Y axes, respectively, The center values MidX and MidY that are represented are calculated as follows.

That is, MidX = (Avxmin + Avxmax) / 2 and MidY = (Avymin + Avymax) / 2.

The difference between Avxmax and Midx, and the difference between Avymax and MidY is 1G (= 1000mG), and the ADC per 1mG considering the X-axis and Y deviation is configured as follows.

And the distance from the center value to x, y is calculated as follows.

With this result in calculating the actual magnetic field strength,

The magnetic field strength (mG) = Distant X (mG per ADC). If the intensity of the magnetic field is calculated and the value is other than 250 ~ 300mG, it is judged that the magnetic field of a certain intensity is over. Alternatively, an alarm may be generated to prevent the user from being exposed to a certain amount of electromagnetic waves through sound.

In the magnetic field alarm device according to the present invention, the earth magnetic field is generally about 250 to 300 mG, which is disturbed by electromagnetic waves of electronic products, and uses a phenomenon in which magnetic field strengths are different in many places such as homes and offices. .

As such, the magnetic field strength may be measured by using a geomagnetic sensor that indicates a direction in the current navigation as a method of measuring the magnetic field strength, thereby indicating how much the user is exposed to electromagnetic waves.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the spirit of the present invention.

Therefore, the technical scope of the present invention should not be limited to the contents described in the embodiments, but should be defined by the claims.

Such an abnormal magnetic field alarm device using a geomagnetic sensor according to the present invention has the following effects.

First, by using the phenomenon that the earth magnetic field is disturbed by the electromagnetic wave of the electronic product, an alarm is generated when a magnetic field of a certain intensity or more enters through the geomagnetic sensor, thereby preventing the user from being exposed to the electromagnetic wave above a certain level.

Second, the electromagnetic wave avoidance is possible by using a geomagnetic sensor applied to the terminal to know the correct direction, thereby increasing the reliability of the mobile communication terminal.

Claims (6)

An X-axis and Y-axis magnetic field detection device for detecting X-axis and Y-axis magnetic fields by drive control of a sensor drive circuit enabled by a CS (Chip Selection) signal; First and second magnetic field amplifiers each amplifying detection values of the X-axis magnetic field detector and the Y-axis magnetic field detector; Digitally convert the amplification values of the first and second magnetic field amplifiers, and use the values to obtain angle = arctan (Y value / X value), and obtain the magnetic field intensity through the distance between the X value and the Y value from the center value. An abnormal magnetic field alarm device using a geomagnetic sensor comprising a magnetic field strength calculation and an alarm control block for outputting an alarm signal in comparison with the control signal. The magnetic field strength calculation and alarm control block is configured to generate an alarm so that the user can know that a magnetic field of a predetermined intensity or more is entered when the obtained magnetic field strength value is other than 250 to 300 mG. Abnormal magnetic field alarm device using a geomagnetic sensor. The abnormal magnetic field alarm device of claim 2, wherein the alarm output from the magnetic field strength calculation and alarm control block is output in a stepwise manner according to the intensity value of the magnetic field obtained using color or sound. . The method of claim 1, wherein the digital values of the digitally converted X and Y axes are x, y, and the minimum and maximum values are Avxmax, Avxmin, Avymax, Avymin. The center value MidX, MidY, Abnormal magnetic field alarm device using a geomagnetic sensor, characterized in that calculated as MidX = (Avxmin + Avxmax) / 2 and MidY = (Avymin + Avymax) / 2. The digital conversion value per mG according to claim 4, wherein the difference between Avxmax and Midx, and the difference between Avymax and MidY is 1G (= 1000mG), and the deviation between the X-axis and Y is taken into consideration.

The distance from the center to x, y is

Abnormal magnetic field alarm device using a geomagnetic sensor, characterized in that the calculated magnetic field strength (mG) = Distant X (mG per ADC). The method of claim 4, wherein in order to obtain analog values of the outputs VXmax, VXmin, VYmax, and Vymin, the magnetic field inside the measurement equipment is measured and a reverse field is applied to cancel the magnetic field inside the measurement equipment. Abnormal magnetic field alarm device using geomagnetic sensor.

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