JPH05333130A - Moving body discriminating device - Google Patents

Abstract

PURPOSE:To seize a moving condition of a moving body by radiating sensor detection output according to the moving content on the moving body side as a radio wave after FM modulation, carrying out demodulation and signal processing on the radio wave after the radio wave is received on the fixed side, storing a pattern corresponding to a specific condition on the fixed side, and comparing the pattern with the received content. CONSTITUTION:A moving body discriminating device is composed of a moving body side device formed by integrating so as to be portable respective ones of an acceleration sensor 11 to detect a moving condition of a moving body, an FM modulator 12 to carry out frequency modulation according to an output condition of this acceleration sensor 11 and a transmitter 13 and an antenna 14 to radiate an output signal of this FM modulator 12 in the air by converting it into a desired frequency and electric power and a fixed side device formed by arranging respective ones of a receiver 22 to receive a transmission signal from this moving body side device, a demodulator 23 to demodulate the output, a pattern memory 25 to store beforehand a pattern corresponding to the content of a specific moving condition and an alarm unit 27 to give an alarm when demodulated output coincides with the pattern in this memory.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a moving body identifying apparatus for grasping the position of a moving body such as a person or a vehicle in a remote place.

[0002]

2. Description of the Related Art For example, there is a GPS (Global Positioning System) as a device for determining the existing position of a moving body such as a person or an automobile. This GPS is a satellite navigation and positioning system constructed and operated by the US Department of Defense, which orbits the earth1.
By receiving 3 or more of the 8 artificial satellites at the same time and processing them computerly, the current latitude and longitude can be displayed accurately, and by receiving 4 satellites, the altitude can be also displayed. I can know. At present, a device that can be placed on the palm is commercially available (for example, there is a positioning system "PYXIS" manufactured by Sony Corporation).

By the way, in recent years, the aging of the elderly is coming to an end in Japan as the life of the elderly becomes longer. Along with such a situation, various kinds of geriatric diseases are becoming new problems. For example,
One of them is senile dementia, which is known to behave in ways that are not normally considered. If such behavior cannot be avoided in advance, it is extremely important to quickly grasp the location of the behavior in order to prevent accidents.

[0004]

In such a case, however, conventionally, there is no choice but to rely on a public institution such as a police, and it is conceivable to bring the above-mentioned GPS when dealing individually. However, this only allows the owner to know his / her position, and cannot transmit his / her position information or other information to others.

Further, a device for always transmitting a radio wave by bringing a transmitting device and knowing the direction of the sender as seen from the receiver by exploring the transmitting direction at the receiving side is conventionally known. ing. However, this does not make it possible to know the condition of the transmitter holder. For example, in the case of a person with senile dementia, it is not possible to comprehend whether or not they are wandering in a sleepwalking state.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems in the prior art, and it is an object of the present invention to provide a moving body identifying apparatus capable of grasping the moving state and moving position of a moving body.

[0007]

In order to achieve the above object, the present invention provides a sensor for detecting the moving condition of a moving body, a frequency modulator for performing frequency modulation according to the output state of the sensor, and this frequency. A mobile-side device in which each of the transmitting means that radiates into the air a desired frequency and power of the output signal of the modulator is integrated, and reception and demodulation for receiving and demodulating the transmission signal from the mobile-side device Means, a memory for storing a pattern corresponding to a specific content of the movement situation in advance, and a processing means for issuing an alarm or the like when the demodulated output matches the pattern in the memory. And is set.

An acceleration sensor is used as the sensor in order to effectively detect the moving condition of the moving body side device.

Further, in order to know the position of the moving body side device, three or more fixed side devices may be provided, and the position of the moving body side device may be determined based on the output signal of each of them.

[0010]

According to the above-mentioned means, the sensor detection output according to the movement content is FM-modulated on the side of the moving body and is emitted as a radio wave, and this radio wave is demodulated and signal-processed after being received by the fixed side. On the fixed side, a pattern corresponding to a specific situation is stored, the pattern is compared with the received contents, and an alarm is issued when they match. Therefore, it becomes possible to determine the moving state of the moving body, for example, to distinguish the unconscious state and the conscious state when the person is the moving body.

By using the acceleration sensor as the sensor, the moving condition (walking direction, moving direction, etc.) of the moving body can be detected as a change in acceleration, and the moving condition can be effectively detected.

Further, by providing three or more fixed side devices, the phase difference between two signals of each can be detected, and the direction and position can be known from the situation.

[0013]

1 is a block diagram showing a basic embodiment of a moving body identifying apparatus according to the present invention.

The identification device is a moving body side device 1 attached to a moving body (such as a sick person or a moving vehicle as described above).
0 and a fixed-side device 20 that receives the radio wave from the mobile-side device 10 and decodes it.

The mobile unit 10 includes an acceleration sensor 11 for detecting an acceleration when the mobile unit moves, and an FM modulator 1 for performing frequency modulation (FM) according to an output voltage of the sensor.
2. Transmitter 13 that multiplies the output signal of this FM modulator 12 to a predetermined frequency and amplifies the power, antenna 14 that radiates the high frequency power of this transmitter 13 into the air, and FM modulator 12 and transmitter 13. Each of the batteries 15 supplies power. The mobile device 10 needs to be made as small and lightweight as possible for use by a person such as a sick person. Then, the transmission output of the mobile device 10 is set to a value that enables communication within the required communication distance.

On the other hand, the stationary device 20 is the moving device 1
Antenna 21 for receiving radio waves from 0, this antenna 2
1, a receiver 22 that amplifies the received signal of 1, a demodulator 23 that demodulates the output signal of the receiver 22, a signal processing unit 24 that performs predetermined processing (waveform recognition, etc.) on the output signal of the demodulator 23, Pattern memory 25, which stores the signal pattern of, the output of the signal processing unit 24 and the pattern memory 2
5 is composed of a comparator 26 for comparing the pattern with the pattern read from No. 5 and an alarm device 27 for issuing an alarm based on the comparison result of the comparator 26.

In the above configuration, for example, if an elderly person suffering from dementia is wandering while wearing the apparatus 10 on the moving body side (the power source is in the ON state), the acceleration sensor 11 outputs an electric signal according to the walking state. Is output. But,
A difference naturally appears in the output acceleration signal when the wearer moves unconsciously and when the wearer moves consciously. Therefore, if the change state of the acceleration is analyzed on the fixed side, the unconscious state and the conscious state can be distinguished. The walking method, the moving direction, and the like are determined to some extent by each person and do not change significantly, so that they can be distinguished with considerable accuracy. The output signal of the acceleration sensor 11 is F
The signal is FM-modulated by the M modulator 12, and further the transmitter 13
After being subjected to processing such as frequency conversion, frequency multiplication, power amplification, etc., it is radiated as a radio wave from the antenna 14.

The stationary device 20 always receives the radio wave from the mobile device 10, and the weak reception signal captured by the antenna 21 is amplified by the receiver 22. Further, the signal is sent to the demodulator 23 for FM demodulation, and then the signal processing unit 24 performs signal processing.

The signal processing section 24 performs signal analysis by FFT or the like. The target of analysis is signal strength, signal repeat cycle (frequency), signal continuous time length monitor, frequency analysis, and the like, and it becomes possible to grasp the state of consciousness of the wearer. On the other hand, the pattern memory 25 stores the data of the signal waveform corresponding to the unconscious state and the conscious state, and when the data is compared with the output signal of the signal processing unit 24 by the comparator 26, when the data matches. To generate an output signal (for example, a signal indicating that an unconscious state has occurred). The alarm 27 is driven by the output signal of the comparator 26, and notifies the fixed waiter of the occurrence of the abnormality.

It is known from the above that the wearer of the mobile device 10 has an abnormality.
By using the stand, the approximate position of the origination point,
Further, by using three or more fixed side devices, it is possible to make a specific position determination. This will be described below step by step.

The output signal from the acceleration sensor 11 is shown in FIG.
Although the waveform is as shown in (a), this signal is transmitted as an FM modulation wave using this signal as a non-carrier, and an acceleration signal is extracted by performing FM demodulation of this modulation wave, and signal processing described later is performed. Signal processing in the unit 24 and the memory 2
By comparing with the data stored in 5, it is possible to obtain an output (for example, an alarm of abnormality occurrence) according to the purpose. Further, as the carrier wave, a high frequency of about 100 MHz (megahertz) to 1 GHz (gigahertz) is used, and since it is FM modulation, the gain of the carrier wave is constant.

On the other hand, the output acceleration signal is generally
Most of the components have extremely low frequencies from about 1 Hz to about 100 Hz. Therefore, various signal processing methods such as FFT and cross-correlation method can be adopted, and the movement state can be grasped in real time. Further, since this acceleration signal output is generally a random signal, as will be described later, the transmission signal from this transmission source is received at two or more different locations, and a time lag (time delay) between the signals is detected. It can be known from the phase shift of the correlation function or transfer function.

In other words, as shown in FIG. 2B, the cross-correlation function of the two signals having only the time lag has the maximum correlation value at the number of delay stages corresponding to the delay time. By knowing the deviation time from the number of delay stages when the value is taken and multiplying by the speed value of the transmitted wave (electromagnetic wave speed), the difference in the distance to the transmission point can be known. It is also possible to obtain the transfer function and obtain it from the phase difference θ. However, θ is −180 ° <θ <+ 180 °
Within.

Now, paying attention to the fHz component of the acceleration signal component, and assuming that the phase shift (on the transfer function) of this frequency is θ °, the time shift is θ ° / (3
Since it corresponds to 60 ° × f), the distance difference to the transmission point can be obtained by multiplying the velocity value of the electromagnetic wave velocity in the same manner.

However, the electromagnetic wave velocity is 3 × 10 ⁸ m / se
Since it is too fast with respect to c, even if there is a distance difference of 10 m, a time difference of 33 nsec (1/30 second) is generated at most. Therefore, even if the phase difference is obtained by focusing on the signal of the 100 Hz component, 10 m is about (1/1
000) °, and the above-mentioned signal processing method cannot actually obtain the resolution, and it is difficult to detect the position with high accuracy.

A method of calculating the delay time from the phase shift of the fundamental wave component of the FM carrier (= extremely high frequency) can be considered, but the time difference can be obtained only within the limit of -180 ° <θ <+ 180 °. However, when the distance difference is large, the frequency of the carrier wave must be lowered, and the measurement range is widened, but the phase resolution is deteriorated, so the accuracy of the distance difference is also impaired, which is not realistic.

With a carrier wave of 1 GHz, ± 0.15 m is a measuring range 100 MHz 〃 ± 1.5 m 〃 1 MHz 〃 ± 150 m 〃 100 KHz 〃 ± 1.5 Km 〃 FIG. 3 shows the second embodiment of the present invention as an accuracy of the distance difference. FIG. 3 is a block diagram of a system configured for good seeking. As shown in FIG. 3, an AM modulator 16 is inserted between the FM modulator 12 and the transmitter 13, and an AM demodulator 28 for performing AM demodulation on the signal from the receiver 22 is added. A dedicated signal processing unit 31 for preparing a phase difference (time difference) between the AM demodulators 28, 28 'by preparing two or more side devices,
A distance difference analysis device including a calculation unit 32 for calculating a distance difference and a display unit 33 is added. That is, the signal processing unit 24 is mainly used for waveform recognition for grasping the moving state, and the signal processing unit 31 performs waveform processing for distance difference detection.

As the AM modulation signal in this embodiment, as shown in FIG. 4, an M-sequence pseudo-random signal or the like is used, which is generated on the mobile side and added with an appropriate DC signal (voltage signal), This signal is used for shallow AM modulation.
That is, although FM modulation and AM modulation are applied twice, the acceleration signal is an extremely low frequency signal up to about 100 Hz, so if the AM modulation wave has a sufficiently high frequency with respect to this acceleration signal, There is no effect on the FM modulated signal side.

Therefore, if the M sequence is generated with a frequency clock of about 1/10 of the frequency of the carrier wave, the frequency component will be on the order of 100,000 times the frequency component of the acceleration signal. AM modulation is possible without any adverse effect.

Further, because of the nature of the M sequence, it can be considered that the signal is usually a random signal.
For the demodulated signal, the signal processor 31 obtains the phase difference of the frequency components to obtain the time difference as described above. However, if the resolution of the phase analysis is about 10 °, carrier electromagnetic waves can be obtained. Since the time difference is obtained with the time resolution of the order of 1 cycle of
2 is obtained with high accuracy and is displayed on the display unit 33.

As described above, for the purpose of highly accurate position detection, the position is known from the transmission delay time of the pseudo random signal such as the M series. For the sake of clarity, the output signal from the acceleration detector is The following will be explained, assuming that it takes the form of the pseudo-random signal.

Considering a state in which the output signal of the acceleration sensor 11 is FM-modulated and is transmitted from the transmitter at the transmission point P by radio waves, the receiving base of this radio wave is as shown in FIGS. 5 (a) and 5 (b). It is assumed that they are provided at two points A and B. (However, it is assumed that the distances PA = l ₁ and PB = l ₂ are set.) Further, it is assumed that the simultaneity of time at the receiving points A and B is completely maintained.

That is, when transmitting a signal to the distance difference analysis device by wire, it is assumed that there is no difference in the time required for the transmission.

The arrival times t ₁ and t ₂ of the signal from the transmission point P to the reception points A and B2 are (C≈3 × 10 ⁸ m / sec) at the reception point A, where C is the velocity of the electromagnetic wave. ₁ = l ₁ / C At the receiving base B, t ₂ = l ₂ / C, and in general, there is a difference between t ₁ and t ₂ . Since the origin point P is usually unknown, the arrival times t ₁ and t ₂ cannot be directly obtained, but since the sources of signals received by the receiving bases A and B are the same, a time lag occurs. However, as described above, it is possible to know the time difference (t ₁ −t ₂ ) by comparing the two signals.

That is, if the required transmission times Td from the two points of the receiving bases A and B to the distance difference analysis device are adjusted to be completely equal, only the time difference (t ₁ -t ₂ ) remains. Is.

Therefore, it is possible to know this time difference with high accuracy by counting with a high-speed reference clock or by the method of peak detection by phase shift or cross-correlation method. (In order to improve the accuracy, the above-mentioned AM modulation method based on the M sequence or the like is actually used.) Since the time difference is (t ₁ −t ₂ ) = (l ₁ −l ₂ ) / C, (l ₁ −l ₂ ) = C × (t ₁ −t ₂ ), and it can be seen that the distance difference can be obtained with high accuracy.

As described above, assuming that the distance difference is obtained from the time difference, this distance difference (l ₁ -l ₂ ) is set to 2La. The distance between points A and B is set to 2Sa. At this time, innumerable points (positions) satisfying | l ₁ −l ₂ | = 2La are considered, and a hyperbola (x ² / La ² ) − {y ² / (Sa ² −La ² )} = 1 ... All locations on the line.

Here, the x-axis is a coordinate axis passing through points A and B, the y-axis is orthogonal to this, and the intersection (origin) is A and B.
The middle of the two points.

However, since the time difference is measured in a form that includes positive and negative signs, it is possible to determine whether the distance difference is positive or negative, and one of the hyperbolas satisfying this result formula can be determined. You can think of it as. That is, the location of the transmission point P is narrowed down to any location on the curve indicated by the solid line in FIG.

As described above, the absolute position cannot be determined by receiving only at the receiving points A and B, but
As shown in FIG. 6 (b), a receiving base C different from the receiving bases A and B is provided, and just as in the case of A and B, between A and C or between B and C (in the figure, between B and C is shown). Example) Obtaining the time difference and calculating the distance difference (l ₃ −l ₂ ) = 2Lb from this value,
Exactly the same as the formula derived from the time difference between points A and B2, (x ' ² / Lb ² )-{y' ² / (Sb on the coordinate axis x'-y 'plane determined at points B and C2. ² −Lb ² )} = 1 ...

In the equation, Sa and Sb are constants uniquely determined from the distance between the receiving bases, and La and Lb can be considered to have already been obtained by the above method. Further, both the xy coordinate axes and the x′-y ′ coordinate axes are the receiving base A,
Since it is determined by B and C, it is not difficult to find the common solution of the formulas by the coordinate axis conversion. This common solution is
Although it is not always one point (two solutions may be obtained), on the contrary, as long as it is a common solution, both the formula and the formula are satisfied, so the transmission point is Certainly it is somewhere in this solution. Furthermore, if the number of receiving bases is increased and the common solution is narrowed down, the point of origin will always be fixed at one point.

In the above embodiment, an example in which the invention is applied to the movement of a person has been shown, but it goes without saying that the invention can be applied to other vehicles such as automobiles and motorcycles as it is. Also, considering the recent pet boom, it may be used for grasping and capturing a pet's voluntary walking activities (escape from a pet hut).

Although the acceleration sensor is used as the sensor in the above embodiment, an ultrasonic sensor, an infrared sensor, or the like may be used to determine the moving state of the moving body from the reflected state of ultrasonic waves or infrared rays from the ground. You may make it the structure to grasp.

[0044]

Since the present invention is configured as described above, it has the following effects.

In the moving body identifying apparatus according to the present invention, a sensor for detecting a moving state of the moving body, a frequency modulator for performing frequency modulation according to an output state of the sensor, and an output signal of the frequency modulator are provided. A device on the side of a mobile unit in which each of the transmission units that radiates in the air at a desired frequency and power is portable, and a reception and demodulation unit that receives and demodulates a transmission signal from the device on the side of the mobile unit, and a specific movement in advance. A fixed side device including a memory for storing a pattern corresponding to the content of the situation, and a processing unit for providing an alarm or the like when the demodulated output matches the pattern in the memory. Therefore, it becomes possible to determine the moving state of the moving body, for example, to distinguish the unconscious state and the conscious state when the person is the moving body.

In the moving body identifying apparatus according to the second aspect, since the sensor is an acceleration sensor, it is possible to effectively detect the moving state of the moving body.

In the moving body identifying apparatus according to the present invention, three or more fixed side apparatuses are provided, and the position of the moving body side apparatus is discriminated based on the output signal of each of them. The position of the device, that is, the position of the moving body can be known.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a moving body identifying apparatus according to the present invention.

FIG. 2 is a waveform diagram of signals in FIG.

FIG. 3 is a block diagram showing a second embodiment of the present invention.

FIG. 4 is a waveform diagram of each signal in FIG.

FIG. 5 is an explanatory diagram for obtaining a transmission point from a reception point.

FIG. 6 is an explanatory diagram for obtaining a transmission point from a reception point.

[Explanation of symbols]

 10 Mobile Side Device 11 Acceleration Sensor 12 FM Modulator 13 Transmitter 14 Antenna 15 Battery 16 AM Modulator 20, 20 'Fixed Side Device 21,21' Antenna 22, 22 'Receiver 23, 23' FM Demodulator 24, 24 'Signal processing unit 25, 25' Pattern memory 26, 26 'Comparator 27, 27' Alarm device 28, 28 'AM demodulator 30 Distance difference analysis device 31 Signal processing unit 32 Calculation unit 33 Display unit

Claims (3)

[Claims] 1. A sensor for detecting a moving state of a moving body, a frequency modulator for frequency-modulating according to an output state of the sensor, and an output signal of the frequency modulator having a desired frequency and electric power and radiated into the air. A mobile unit in which each of the transmitting units is integrated in a portable manner, a receiving unit for receiving and demodulating a transmission signal from the mobile unit, and a demodulating unit, and a pattern corresponding to a specific movement situation content are stored in advance. An apparatus for identifying a mobile body, comprising: a memory; and a fixed-side device that is provided with each of processing means for issuing an alarm or the like when the demodulated output matches a pattern in the memory. 2. The apparatus for identifying a moving body according to claim 1, wherein the sensor is an acceleration sensor. 3. The moving body identifying apparatus according to claim 1, wherein three or more fixed side apparatuses are provided, and the position of the moving body side apparatus is discriminated based on an output signal of each of the fixed side apparatuses.