JPH05312932A - Electronic coniometer - Google Patents

Abstract

PURPOSE:To confirm in which azimuth the other party is located between the persons carrying electronic goniometers to each other. CONSTITUTION:A transmitting part 18, a receiving part 17, a magnetism detecting part 16 and a display part 2 are provided in an electronic azimuth instrument. Signals are transmitted from the transmitting parts 18 of the electronic goniometer and another electronic goniometer having the same constitution to the opposite sides to each other at a specified time interval. At the time of detection, the signals from the opposite sides are received with the receiving parts 19. The intensity of the received signals are detected, and the azimuth where the maximum signal strengths is obtained is detected. The azimuth when the maximum signal intensity is obtained is made to be the azimuth of the target, and the azimuth is displayed or announced with a sounds.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic compass,
In particular, the present invention relates to an electronic azimuth meter having a transmission / reception function and capable of confirming mutual azimuths between at least two electronic azimuth meters.

[0002]

2. Description of the Related Art Conventionally, an electronic azimuth meter has been developed which calculates and displays the direction of the earth's magnetism by utilizing a magnetic detection element (a magnetoresistive element, a Hall element, a ferromagnetic material, etc.). This electronic azimuth meter has also been made smaller and lighter by the integration technology, and can be used by mounting it on an arm like a wristwatch.

[0003]

By the way, the conventional electronic azimuth meter has only the function of detecting the azimuth and is used alone. However, since there is a function that can detect the direction, if you have a function that allows you to confirm which direction the other party is in between multiple electronic azimuth meters other than using it alone, It is very convenient for use in the mountains and waiting in large areas. It can be said to be particularly useful for finding out in case of distress.

Therefore, an object of the present invention is to provide an electronic azimuth meter capable of confirming in which direction a plurality of partners are in each other.

[0005]

To achieve the above object, an electronic azimuth meter according to the present invention comprises transmitting means for transmitting a signal at a predetermined time interval, and receiving means for receiving the signal transmitted by the transmitting means. Signal strength detecting means for detecting the strength of the signal received by the receiving means, azimuth detecting means for detecting the azimuth when the signal strength detected by the signal strength detecting means is maximum, and detection by the azimuth detecting means And an informing means for informing the azimuth thus set.

[0006]

According to the present invention, when the signal transmitted from the other party is received, the strength of the received signal is detected, and further the direction in which the strength is maximized is detected. Then, when the azimuth at which the intensity is maximized is detected, a notification (for example, a display on the display unit, a notification sound such as a sound) is given. Therefore,
Since the direction in which the strength of the received signal is maximum is the direction in which the other party is, it is possible to mutually confirm the directions in which the other party is.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG. 1 is a front view showing an embodiment of an electronic azimuth meter 1 according to the present invention, and FIG. 2 is a plan view showing an example of the display. This electronic azimuth meter 1 is formed in a disk shape like a general wristwatch, and a display unit 2 composed of a liquid crystal display is attached to the entire surface thereof. The display shown in FIG. 2 is displayed on the display unit 2. In this figure, 3 is a bezel display area. In this area 3, a mark (“◯”) 4 indicating a target direction (direction of the other party) and a mark (“●”) 5 indicating a north direction which is a magnetic needle are shown. Is displayed.

The bezel is generally a metal ring surrounding the glass surface of the watch surface, and there are two types that can be rotated by the user and one that cannot be rotated. The Bethel of this embodiment is displayed on the peripheral portion of the display unit 2.

Continuing on, in FIG. 2, reference numeral 6 denotes a target azimuth display area, in which the target azimuth (7) and the direction 8 are displayed. In this figure, "northwest" and "315 °" are displayed. Further, the north, south, east, west (E, W, S, N) is also displayed in the present direction display area 6.

Returning to FIG. 1, a push button type detection switch 9 is provided on the side surface of the electronic azimuth meter 1, and the detection mode is executed while the detection switch 9 is being pushed. The detection mode is a process of detecting the azimuth (the above-mentioned target azimuth) in which the user carrying the electronic azimuth meter similar to this embodiment is.

Next, FIG. 3 is a block diagram showing the configuration of the electronic azimuth meter 1. In this figure, 10 is a CPU (central processing unit), which controls each part of the electronic azimuth meter 1.
This CPU 10 has a ROM (Read Only Memory) 1
1, a RAM (random access memory) 12, an interface circuit 13, and a notification signal generation circuit 14 are provided. A program for controlling the CPU 10 is written in the ROM 11, and the CPU 10 measures the azimuth according to the program and displays the result. Also, the azimuth of the user who carries another electronic azimuth meter having the same function is detected, and the azimuth is displayed and notified.

A plurality of areas are secured in the RAM 12, and various measurement results are written in these areas. Here, Table 1 shows a part of the contents of the RAM 12.

[0013]

[Table 1]

In Table 1, the order of "D1", "X", "Y", "X1" from the beginning of the address is
Areas such as "X2", "Y1", "Y2", "signal strength", "maximum signal strength", "D2" are secured. D1
The azimuth is written in the area, and the detected magnetism (hereinafter, detected data) is written in each of the X1, X2, Y1, and Y2 areas. Further, in the X area, the difference (X1-
X2) is written, and the difference (Y1-Y2) of the detection data in the Y direction is written in the Y area. In this case, the detection data is output from the magnetic detection unit 16 described later. The details will be described later. The measured signal strength is written in the signal strength area. The maximum measured signal strength is written in the maximum signal strength area. The azimuth at the maximum signal strength, that is, the target azimuth is written in the D2 area.

The interface circuit 13 exchanges data between each unit of the electronic azimuth meter 1 and the CPU 10. The notification signal generation circuit 14 outputs a notification signal in response to a command from the CPU 10 and causes the speaker 15 to generate a notification sound.

Returning to FIG. 3, reference numeral 18 denotes a transmitter, which is a CPU.
11 and is controlled by a fixed time interval (for example, 20 mse
In c), the signal is transmitted on a carrier having a predetermined frequency.
The receiving unit 17 extracts only a signal of a predetermined frequency from the signals transmitted from the outside, digitally converts the intensity thereof, and outputs it. In this case, the output data is input to the CPU 11 when the detection mode is selected and written in the signal strength area of the RAM 12 as described above. Also,
At this time, the data corresponding to the maximum signal strength is written in the maximum signal strength area, and the direction in which the signal strength is obtained is written in the D2 area.

Here, FIG. 4 is a diagram showing the azimuth and the signal strength characteristic, and the azimuth having the maximum signal strength is the target azimuth. In this case, the receiving unit 17 has an antenna 1 with high directivity.
9 is connected, and the higher the directivity of the antenna 19, the sharper the curve shown in FIG. That is,
Therefore, the target direction can be accurately captured. On the other hand, an omnidirectional antenna 20 is connected to the transmitter 18. In this embodiment, the transmitter 18 and the receiver 17 use the same frequency, but different frequencies may be used. In this way, by using different frequencies, or by giving a signal an ID (Identifier number) code or the like, it is possible to recognize between a plurality of (3 or more) electronic azimuth meters.

Returning to FIG. 3, the magnetic detector 16 detects magnetism to detect each of the X, Y, X1, X2, Y1 and Y described above.
The detection data of 2 is output. Reference numeral 21 is a switch unit having the detection switch 9, and its output is input to the CPU 10.

FIG. 5 is a block diagram showing the structure of the magnetic detector 16. Further, FIG. 6 shows the magnetic detection unit 16
FIG. 7 is a plan view showing the structure of the magnetic sensor 22 constituting the above, and FIG. 7 is a circuit diagram showing the electrical configuration of the magnetic sensor 22. First, in FIG. 6, the magnetic sensor 22 includes four magnetic resistance elements M on a substrate 23 formed of glass or alumina.
R1 to MR4 and four pads P1 to P4 are formed. In this case, the magnetoresistive elements MR1 to MR
Each of the magnetic field detectors 4 is coupled to the adjacent magnetic resistance element so that the magnetic detection direction differs by 90 degrees, and the detection direction has an inclination of 45 degrees with respect to the measurement direction N.

Further, the magnetoresistive elements MR1 to MR4 are connected in a bridge shape as shown in FIG. 7, and a voltage V is applied between the connection points K1 and K3. In this case, as is well known, the resistance value of the magnetoresistive element changes due to the action of a magnetic field, and the connection point K of the magnetoresistive elements MR1 to MR4 which are now bridge-connected.
When the voltage V is applied between 1 and K3, the resistance value changes due to the action of the magnetic field, and a potential is generated between the connection points K2 and K4.
In this case, if the potential of the connection point K2 is V1 and the potential of the connection point K4 is V2, a potential difference VS of V1-V4 occurs between the connection points K2 and K4.

In the magnetic sensor 22, two bias coils C1 and C2 shown in FIG. 5 are wound around the magnetoresistive elements MR1 to MR4 so that they are orthogonal to each other. Of these, the bias coil C1 supplies the supplied current. 6, a bias magnetic field in the direction of arrow B1 shown in FIG. 6 and the opposite direction of arrow B3 (hereinafter referred to as bias magnetic fields B1 and B3) is applied to the magnetoresistive elements MR1 to MR4. On the other hand, the bias coil C2 generates a bias magnetic field (hereinafter referred to as a bias magnetic field B2, B4) in the arrow B2 direction shown in FIG. 6 and the opposite arrow B4 direction depending on the direction of the supplied current. Apply to.

Returning to FIG. 5, reference numeral 24 is an element driving section for applying a voltage V between the connection points K1 and K3 of the magnetic sensor 22.
Reference numeral 25 is a differential amplifier circuit, which is a connection point K of the magnetic sensor 22.
The detection voltages V1 and V2 at 2 and K4 are input, and the difference voltage VS (V1-V2) is amplified and output. 26 is A /
It is a D (analog / digital) conversion circuit, which digitally converts the difference voltage VS output from the differential amplifier circuit 25 and outputs it to the register 27. Further, the A / D conversion circuit 26 is
The in-conversion signal Sb is output during the / D conversion.

Reference numeral 28 is a coil drive circuit for supplying bias currents I1 and I2 to the bias coils C1 and C2. In this case, the directions of the bias currents I1 and I2 are reversed to generate the bias magnetic fields B1 and B3 and the bias magnetic fields B2 and B4 as described above.
4 is applied. The bias currents I1 and I2 are alternately flowed and their directions change, so that the bias magnetic fields B1 to
B4 occurs in the order of B1 → B2 → B3 → B4.

Reference numeral 29 is a waveform synthesizing circuit, which outputs signals S1 to S4 for operating the coil driving circuit 28 as described above, and R corresponding to the bias magnetic fields B1 to B4.
Area signals A1, A0 indicating the storage areas of the detection data X1, X2, Y1, Y2 of the AM 12 are output to the register 30.
Further, it outputs a conversion timing signal Sa for instructing the A / D conversion timing based on the signals S1 to S4 to the A / D conversion circuit 26. Further, during the A / D conversion of the A / D converter 26, the in-conversion signal Sb output from the A / D converter 26 is input.

Further, the waveform synthesizing circuit 29 instructs the CPU 10 to start the data rewriting process by the interrupt signal I.
Output NT. In this case, the interrupt signal INT is output every predetermined time (for example, 1 msec). CPU10 is RAM1 based on the interrupt signal INT
The rewriting process of the data of 2 is performed. That is, D1, X,
The values of Y, X1, X2, Y1, Y2, signal strength, maximum signal strength, and D2 are rewritten. However, if the detection mode is not selected, signal strength, maximum signal strength, D2
Each value of is not rewritten.

The register 27 has detection data X1, X2, Y of the potential difference VS output from the A / D conversion circuit 26.
1 and Y2 are temporarily stored and output in response to a request from the CPU 10. Further, the register 30 is a waveform synthesis circuit 29.
Temporarily store the area signals A1 and A0 output by
Output in response to a request from the CPU 10.

Detection data X1 and X of the RAM 12 described above
Of the 2, Y1 and Y2 storage areas, the X1 and X2 areas are
Bias coil C1 allows magnetoresistive elements MR1 to MR4.
The detection data X1 and X2 of the potential difference VS obtained when the bias magnetic fields B1 and B3 are applied to are stored. Also,
In the Y1 and Y2 regions, the detection data Y1 and Y2 of the potential difference VS obtained when the bias magnetic fields B2 and B4 are applied to the magnetoresistive elements MR1 to MR4 by the bias coil C2.
Is stored. The difference between the detection data X1 and X2 is stored in the X area of the RAM 12, and the detection data Y is stored in the Y area.
The difference between 1 and Y2 is stored. The detailed contents of the magnetic detector 16 are described in the specification (Japanese Patent Application No. 4-82846) which has already been filed by the present applicant.

The CPU 10 detects the detection data X of the potential difference VS.
1, X2, Y1, Y2 are the areas X1, X2,
After storing in Y1 and Y2 and performing a calculation to obtain the difference X between the detection data X1 and X2 and the difference Y between the detection data Y1 and Y2,
The data is stored in the areas X and Y of the RAM 12, and then the azimuth calculation processing is performed. The calculation of this azimuth is obtained by Equation 1.

[0029]

[Equation 1]

However, since the value of tan ⁻¹ (Y / X) is 0 ° to 360 °, it cannot be determined.
As shown in, the azimuth is discriminated based on the magnitude of the values of the difference X and the difference Y.

[0031]

[Table 2]

That is, when the values of the difference X and the difference Y are both positive, the azimuth is obtained by the formula 1, and when the difference X is negative, the formula 1 is obtained.
Then, the azimuth is calculated by the formula in which 180 is added. Further, when the difference X is positive and the difference Y is negative, the azimuth is obtained by the equation obtained by adding 360 to the equation 1.

The receiving section 17 corresponds to receiving means, and the transmitting section 18 corresponds to transmitting means. Further, the CPU 10 is the RO
M11 and the signal strength detection means 35 are configured, and R
The OM 11 and the magnetic detector 16 constitute the azimuth detecting means 36. Further, the CPU 10 constitutes the notification means 37 together with the notification signal generation circuit 14.

Next, the operation in the detection mode of the electronic azimuth meter 1 having the above structure will be described with reference to the flow chart shown in FIG. This detection mode is used to detect the azimuth (target azimuth) where the user carrying the electronic azimuth meter having the same function is, and the electronic azimuth meter 1 is rotated once to detect the azimuth. At this time, the target azimuth is the azimuth in which the signal intensity is the highest. Of course, when the detection mode is used with the electronic azimuth meter 1 worn on the wrist, the user may make one rotation.

When the detection switch 9 is pushed, the measurement of the signal strength is started in step S1. When this measurement is started, the CPU 10 measures the signal strength each time the interrupt signal INT output from the magnetic detection unit 16 is input and writes the signal strength in the signal strength area of the RAM 12, and further, in step S2, the current signal strength. Is greater than the maximum signal strength.

If it is determined in this determination that the current signal strength is higher than the maximum signal strength, the current signal strength is written in the maximum signal strength area of the RAM 12 in step S3. Then, in step S4, the azimuth is measured and written in the D2 area of the RAM 12. Next, the process proceeds to step S5, and it is determined whether or not one rotation (rotation by 360 degrees) has been performed. This determination is made based on the azimuth (north azimuth) calculated based on the detection data X1, X2, Y1, Y2 output from the magnetic detection unit 16. That is, it can be determined that one rotation has been made when the original azimuth appears.

On the other hand, if it is determined in step S2 that the current signal strength is smaller than the maximum signal strength, nothing is done and the process proceeds to step S5. If it is determined in step S5 that one rotation has been performed, the process proceeds to step S6, the azimuth at which the maximum signal strength is obtained (target azimuth) is displayed on the display unit 2, and a notification sound is generated.

In the above embodiment, the electronic azimuth meter 1 is rotated once during execution of the detection mode, or the user himself is rotated once while the electronic azimuth meter 1 is worn on the arm. It may be rotated by a motor or the like.

Further, in the above embodiment, the display of the target azimuth is represented by the direction (north, east, west, north and south), the azimuth and the mark "○", but the display is not limited to this. Further, the target direction may be notified by voice.

Further, the above embodiment may be provided with a clock function.

[0041]

According to the present invention, the signal transmitted from the other party is received, and the direction in which the intensity of the received signal is maximized is detected and notified. Since it is possible to confirm which direction the other party is in, it becomes very convenient for use in the mountains and waiting in a large area, and it is particularly useful for finding out in case of distress.

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment of an electronic azimuth meter according to the present invention.

FIG. 2 is a plan view showing a display of the electronic azimuth meter according to the embodiment.

FIG. 3 is a block diagram showing a configuration of an electronic azimuth meter according to the same embodiment.

FIG. 4 is a diagram for explaining a relationship between an azimuth and a signal strength in the electronic azimuth meter of the same embodiment.

FIG. 5 is a block diagram showing a configuration of a magnetic detection unit of the electronic azimuth meter according to the same embodiment.

FIG. 6 is a plan view showing a configuration of a magnetic sensor of the electronic azimuth meter according to the embodiment.

FIG. 7 is an equivalent circuit diagram of a magnetic sensor of the electronic azimuth meter according to the embodiment.

FIG. 8 is a flowchart for explaining the operation of the electronic azimuth meter according to the same embodiment.

[Explanation of symbols]

 2 display section 9 detection switch 10 CPU 11 ROM 14 notification signal generation circuit 16 magnetic detection section 17 receiving section (receiving means) 18 transmitting section (receiving means)

Claims (1)

[Claims] 1. A transmitting means for transmitting a signal at a predetermined time interval, a receiving means for receiving the signal transmitted by the transmitting means, and a signal strength detecting means for detecting the strength of the signal received by the receiving means. And an azimuth detecting means for detecting an azimuth when the signal strength detected by the signal strength detecting means is maximum, and an informing means for informing the azimuth detected by the azimuth detecting means. An electronic compass.