JP2859399B2 - Inbound / outbound counting device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to an inbound / outbound counting device, and more specifically, in a closed space such as a road, a tunnel, an underground structure, or a building. Is divided into appropriate areas, and an entrance / exit counter that can detect the presence of a person in each area.

<Problems to be solved by the conventional technology and the invention> In a closed space in a road where cables and the like are to be laid, an underground tunnel, a basement, or a building, humans enter and exit as needed to perform work and work. It can be regarded as a closed space system.

Work in a closed space is difficult to observe from the outside, and if an entrant is left inside, it can lead to a serious accident. For this reason, it is very important to always observe and grasp how many people or who is in which area of the closed space. When an abnormal situation such as a fire accident occurs near the place where the entrant is present, it is also important to inform the outside of the situation and take some measures.

For this reason, in a business entity that manages closed spaces such as roads, a management center is provided to observe and grasp the number of visitors and their identification numbers (ID) in each area in the closed space.

That is, in the related art, as shown in FIG. 17, infrared counters 21, 22, 23,... Are provided at appropriate boundaries in a closed space 1 such as a road and the like, and a person passes in front of the counters. Was counted, and the number of counts of each counter was processed to control the number of persons present in each area.

Although this system is economically advantageous in that it uses a simple infrared counter, human behavior is complex and it can make multiple round trips in front of a single counter or multiple people. If they cross the counter side by side, the number of visitors in each area will not match the calculation. In addition, counting errors occur even if the machine crosses in front of the counter. If such an error occurs, the purpose of the present system for reliably grasping the number of people cannot be achieved.

Therefore, each entrant has a wireless transmission terminal,
It is also conceivable to install a receiving antenna in each area of the premises and estimate the position of the entrant in an area corresponding to the receiving antenna that has most strongly received the radio wave emitted from the wireless transmission terminal.

However, in this method, radio waves are considered to travel to a distant place with little attenuation in the road or tunnel, so the radio waves emitted from the wireless transmission terminal owned by the entrant are received by many receiving antennas, and the position of the entrant is Is difficult to determine. It is even more difficult if the radio waves fade.

It is conceivable that the current position is notified from the wireless transmission terminal by voice. However, it is costly to prepare a large number of voice wireless transmitters, and a complicated operation is required for the visitors, and there is almost no practicality.

The present invention has been made in view of the above problems, and an object of the present invention is to make it difficult for an entrant to determine in which area the occupant is located in an enclosed space such as an underground structure or a building. It is an object of the present invention to provide an entry / exit counter that does not require a simple operation and can accurately detect.

<Means and Actions for Solving the Problems> To achieve the above object, an entrance / exit counter according to claim 1, as shown in FIG. An electromagnetic wave at a frequency less than or equal to the frequency fc (an electromagnetic wave is a wave in which a magnetic field and an electric field alternately fluctuate, so it can also be regarded as a magnetic field wave. (The expression may be used.) The user possesses a transmitter terminal 4 that generates a (guidance field), and vertically divides a closed space 1 such as a road into a plurality of areas along a road in the space, and respectively. The guide wire loop antenna 3 is installed so as to be substantially parallel to the road in the area of (1). An antenna controller 8 for converting a signal voltage induced in the inductive wire loop antenna 3 to an intermediate frequency signal is connected to a terminal of the induction wire loop antenna 3, and the central control device 6 and the plurality of antenna controllers 8 are connected to each other. The sections are connected via a common signal transmission line 5. That is, the antenna controller 8 is connected to the branch line 9 with respect to the signal transmission line 5.
Are connected in a branched configuration.

As shown in FIG. 2, the transmitter terminal 4 includes a driver 41 for generating an alternating current having a frequency f equal to or lower than the lowest frequency fc.
And an antenna 42. When the antenna 42 is driven at a frequency f equal to or lower than fc, an AC magnetic field H is generated from the antenna 42. The AC magnetic field H is an induction field,
As shown in the figure, it has a characteristic that the intensity is rapidly attenuated with the distance D.

The transmission and reception of signals between the central management device 6 and the antenna controller 8 is performed by a polling method. Therefore, each antenna controller 8 is assigned an address, and the signal transmission line 5 transmits the above-mentioned intermediate frequency signal obtained by converting the voltage induced in the dielectric wire loop antenna 3 to the intermediate frequency. A polling signal line 11 and a response signal line 12 are included in addition to the terminal signal line 13 for the communication.

The polling signal line 11 transmits a polling signal supplied from the central management device 6 and specifying an address of one of the antenna controllers 8.

The response signal line 12 derives a response signal including its own address when its own address matched by each antenna controller 8 matches the address in the polling signal.

Although not shown, the antenna controller 8 has a switch for connecting / disconnecting between the antenna controller 8 and the terminal signal line 13, and the address in the polling signal coincides with its own address. Sometimes, the antenna controller and the terminal signal line 13 are connected by a switch, and when a polling signal specifying a combined address other than the own address is received, the antenna controller and the terminal signal line are connected. And a switching controller for performing switching control of the switching device for shutting off.

Further, the antenna controller 8 includes a function check switch for loading a function check program for checking at least one of the following items (a) to (d) into the switching controller: (a) power supply voltage Value (b) Output level of local oscillator for intermediate frequency signal conversion (c) Self-address of antenna controller (d) Generation of pseudo polling signal including self-address of each antenna controller and when polling with self-address A reception confirmation function for confirming whether or not to perform a predetermined operation; and an operation confirmation display for displaying a result of the function check.

With the above configuration, the magnetic field H generated from the transmitter terminal 4 is linked with only the guide wire loop antenna 3 installed in the area where the entrant is located due to its locality, and thus the guide wire loop antenna 3 to induce a voltage. The induced voltage signal is guided to the central control device 6 when the antenna controller 8 receives the polling signal, and the central control device 6 can observe the induced voltage generated in each induction wire loop antenna 3. .

Then, the central management device 6 can identify the induction wire loop antenna 3 in which the voltage has been induced, and specify the area where the induction wire loop antenna 3 is installed as the presence area of the entrant.

Further, according to such a configuration, since the signal transmission lines 5 are shared, the number of signal transmission lines can be reduced.

Further, by operating the function check switch, the function of the antenna controller can be checked on the side of the antenna controller by operating the function check program.

<Example> Hereinafter, an example will be described in detail with reference to the accompanying drawings.

FIG. 4 is a schematic diagram showing a specific example of an entrance / exit counting apparatus, in which a plurality of areas are set in a road, and parallel guide wire loop antennas 3a, 3b, 3c,. "). The entrant has their own transmitter terminals 4a, 4b, 4c,... (Hereinafter, represented by reference numeral "4"). The induction line loop antenna 3 has antenna controllers 8a, 8b, 8c,... (Hereinafter referred to as reference numeral "8") for frequency-converting the induced signal voltage into a signal having a customary frequency (hereinafter referred to as "intermediate frequency signal"). .) Is connected.

Signal transmission between the central management device and the plurality of antenna controllers 8 is performed by sharing the signal transmission line 5 connected to the central management device 6. That is, the plurality of antenna controllers 8 are commonly connected to the signal transmission line 5 via branch lines 9a, 9b,... (Hereinafter, represented by reference numeral “9”). With this configuration, a polling method is applied, and the antenna controller 8
A signal is transmitted between the terminal and the central management device 6. Reference numeral 10 denotes a branching device for branching the signal transmission line 5 into different observation regions.

The signal transmission line 5 includes a polling signal line 11 from which the central management device 6 derives a polling signal, a response signal line 12 for transmitting a response signal from the antenna controller 5 specified by the polling signal, and a transmitter terminal. And a terminal signal line 13 for transmitting the above-mentioned intermediate frequency signal obtained by converting a signal voltage generated in the induction wire loop antenna 3 by the magnetic field from 4 into an intermediate frequency signal.

An address is individually assigned to each of the plurality of antenna controls 8, and the central management device 6 derives a polling signal specifying an address corresponding to any one of the antenna controllers 8, so that any one of the antenna controls 8 is controlled. Table 8
In response to this, the antenna controller 8 having the address assigned thereto derives a response signal including its own address on the response signal line, and transmits the response signal to the terminal signal line 13 to the transmitter terminal 4. Derive an intermediate frequency signal corresponding to the signal from

FIG. 5 is a block diagram showing the configuration of the antenna controller 8. The polling signal from the polling signal line 11 is received by the receiver 22 via the coupler 21. The polling signal has a format as shown in FIG. That is, the start bit (STX),
The address of the antenna controller 8 to which transmission is permitted, an error detection bit, and an end bit (PAD) are transmitted.

The polling signal received by the receiver 22 is supplied to an address determination circuit 23, and an address in the polling signal and a memory 25 allocated to the antenna controller 8 and connected to a CPU (central processing unit) 24 are stored in the memory 25. Collation with the stored address is performed. When the two addresses match, the CPU 24 gives the address stored in the memory 25 and other necessary data to the response signal generation circuit 26, and the response signal generated based on the address is sent from the transmitter 27. The signal is output to the response signal line 12 via the coupler 28. The format of the response signal is shown in FIG. 7 and includes a synchronization signal, a start bit (STX), an address of the antenna controller 8, an error detection bit, and an end bit (PAD).
It is comprised including.

What is the signal voltage induced in the induction loop antenna 3? The signal is supplied to the frequency converter 30 via the balloon 29. The frequency converter 30 mixes the signal supplied from the balloon 29 with the reference frequency signal from the local
This is to convert the frequency of the signal from 29 into an intermediate frequency signal. This intermediate frequency signal passes through a switch 33 that can be switched by a switch operation circuit 32 based on the output of the address determination circuit 23, and further from a coupler 34 to a terminal signal line.
Derived to 13. The switching operation circuit 32 includes an address determination circuit
Only when an address match is detected at 23, the switch 33 connects the frequency converter 30 and the coupler 34.

The antenna controller 8 is a device including a CPU 24 inside,
It is important for maintenance and operation to be able to check the instruction control operation of the PU24 and confirm that there are no abnormalities.

Therefore, as shown in FIG. 5, the CPU 24 is provided with a function check program 38 and a function check switch 39,
When the function check switch 39 is operated, the function check program 38 can be loaded. At this time, it is not desirable that the result of the operation by the function check program 38 be input to the central control device 6 as a response signal. Therefore, the operation of the response signal generation circuit 26, the transmitter 27, and the coupler 28 should be stopped during the function check. ing. By displaying the result of the function check on the operation confirmation display 36 on the LED lamp 361 or the digital digital display 362,
Inspectors can easily check.

Check function of function check program 38
It is selected from at least the following:

Checking the power supply voltage value Checking the output level of the local oscillator 31 Checking the self-address of the antenna controller 8 Checking the pseudo polling signal receiving function The function of checking the pseudo polling signal receiving function is included in the function check program 38 The addresses (for example, 600, 601, 602, 603,..., 6; 6 are group addresses) of all the antenna controllers 8 existing in the system are stored in the memory, and these addresses (600, 601, 602,
Pseudo polling signals including 603,..., 6) are sequentially created in the CPU 24, and are polled by the self address (for example, 600) of the antenna controller 8 or group polled by the group address (for example, 6). At this time, it is checked whether a predetermined operation is performed.

FIG. 8 is a cross-sectional view of the road, where the width of the road is W.
Indicated by Cut-off wavelength λ when viewing the path as a waveguide
Since c can be approximated by λc = 2W, the cutoff frequency fc at which the electromagnetic wave can be carried is: fc = c / 2W (c is the speed of light). The transmission frequency f of the transmitter terminal 4 is selected to be lower than the cutoff frequency fc in order to eliminate the propagation of electromagnetic waves in the road.

The induction line loop antenna 3 may be installed at any position according to the shape of the road 1 as long as it can receive an AC magnetic field. For example, it may be installed along the ceiling of the tunnel-shaped road 1 as shown in FIG. 9 (a), or may be installed along both side walls as shown in FIG. 9 (b). As shown in FIG. 3 (c), it may be installed along the bottom of the road 1,
It may be installed along one side wall as shown in FIG. In particular, a position close to the bottom surface as shown in FIG. 3C is preferable because even if a human being with a transmitter terminal falls down in the event of an accident, it can be reliably detected.

FIG. 10 shows the frequency characteristics of the spatial noise level (equivalent noise figure) up to several tens of MHz standardized by CCIR (in the figure, A is a business area, B is a residential area, C is a rural area, D is Shows a quiet rural area, CCIR Report 25
8-4). FIG. 11 shows the frequency characteristics of the equivalent noise figure actually measured in the actual road, and the noise decreases as the frequency increases. Therefore, in order to reduce the influence of city noise, it is preferable to select the frequency f as high as possible in a range smaller than fc.

In order to reduce the influence of noise, it is important that the magnetic field is detected by the induction loop antenna 3 as efficiently as possible. FIG. 12 shows a model for calculating the reception efficiency.
D, the wire diameter is 2r, and the distance from the center of the parallel guide wire loop antenna 3 to the transmitter terminal 4 is X. Coupling coefficient C [d between the induction loop antenna and the transmitter terminal
B] is, given that ω is an angular frequency and A is a predetermined coefficient, Becomes From this equation, it can be seen that the coupling coefficient C increases in proportion to the square of the frequency.
It is preferable that the value be higher in a range smaller than fc.

Next, a specific designated index of the frequency f will be described. 8th
A road having a width W in the figure is assumed. The cutoff frequency is
Using the formula, Since the radio wave does not propagate below this frequency, the only possible electromagnetic wave is a local guidance field. fc
The attenuation constant of the electromagnetic wave in the length direction of the road at the following frequency f is approximately determined by using the waveguide theory, It is estimated to be.

If the width of the road is W = 5 m, fc = 30 MHz from the equation. However, with some margin, f = 20 MHz is selected. From the formula,
An attenuation coefficient α = 4 dB / m is obtained. According to this, the attenuation is 40 dB at a distance of 10 m and 80 dB at a distance of 20 m, so that the locality of the magnetic field can be sufficiently achieved.

It is preferable that the ends of the parallel induction wire loop antenna 3 are connected by a resistor Ro having a value substantially equal to the characteristic impedance of the antenna (see FIG. 13A).

For example, if the frequency f is 20 MHz, the wavelength is 15 m. Assuming that the length of the guide wire loop antenna is 100 m, the length of the loop antenna becomes sufficiently longer than the wavelength. In such a case, if the conductor is short-circuited instead of the resistor Ro, as shown in FIG. 13 (b), the coupling degree C between the inductive edge loop antenna and the transmitter terminal becomes a wave every 1/2 wavelength. It becomes a standing wavy shape. For this reason, when the position of the transmitter terminal 4 comes to the position of the valley of the standing wave, it will not be coupled to the induction loop antenna. Therefore, as shown in FIG. 13 (a), when the end of the induction wire loop antenna is connected with a resistance Ro substantially equal to its characteristic impedance, the coupling C between the induction wire loop antenna and the transmitter terminal is almost equal at any position. The transmitter terminal can be detected at any position.

In this entry / exit counter, the transmitter terminal 4 has an identification number (hereinafter, referred to as "ID"), and not only detects the presence of an entrant but also performs individual identification of the entrant. .

FIG. 14 shows a format of a modulated signal of a magnetic field generated from the transmitter terminal 4. The preamble, the synchronization bit, the start bit (STX) are followed by the affiliation of the participant.
ID bit, error detection bit, end bit (PA
D). In the central control unit 6, if each AC voltage signal received through the signal line 5 is demodulated, and the ID bit contained therein is decoded and detected, it is possible to determine the affiliation of the entry and the individual judgment thereof.

Table 1 shows each area A, B, C,
.. Shows a table of the number of visitors and the IDs (001, 002, 003,...) Of the visitors who enter the area.

Next, a second embodiment will be described.

The guide wire loop antenna 3 includes a transmitter terminal 4
Since it is an important facility for detecting the presence of a entrant, if it is disconnected or short-circuited, the detection of an entrant becomes impossible. However, since the guide wire loop antenna 3 is usually laid in a wide range, it is not easy to examine the broken state in detail. Therefore, by installing the antenna condition monitoring device 2 as in the present invention, the inspector can check the closed space 1.
It was decided to easily know whether the antenna was short-circuited or damaged while looking inside.

Hereinafter, the configuration of the antenna state monitoring device 2 will be described. No.
As shown in FIG. 15, the connection terminal of the induction wire loop antenna 3
A filter composed of a capacitor C and a coil L connected near 31, a voltage source E, and a series resistor Rs are mounted. The voltage across the series resistor Rs can be externally measured with a voltmeter V. Of course, the voltmeter V may be incorporated in the antenna condition monitoring device 2.

The filter passes the signal of the transmission frequency f induced by the induction loop antenna 3 to the connection terminal 31.
The current flowing from the voltage source E (hereinafter referred to as “test current”) is cut off so as not to flow into the connection terminal 31. Therefore, when viewed from the induction loop antenna 3, the filter does not become a load for the signal of the frequency f.

The test current flowing from the voltage source E flows as long as the induction loop antenna 3 is not disconnected, and its value It is the voltage E, the resistance r of the induction loop antenna 3, the series resistance Rs, and the value of the induction loop antenna 3. It is determined by the terminating resistor Ro (described later).

Therefore, the voltage V across the series resistor Rs is Becomes Here, it is assumed that the resistance r is sufficiently smaller than the resistance Rs.

When the induction loop antenna 3 is disconnected, the current It does not flow, so that V = 0.

When the induction loop antenna 3 is short-circuited, Ro → 0 is set, Becomes

Numerical examples of E = 5V, Rs = 500Ω, Ro = 600Ω, and r ≒ 0 are as follows: V ≒ 2.3V when the antenna is normal, and V ≒ 5V when the antenna is short-circuited. Therefore, the measured values of the voltmeter V are 2.3 V, 5 V, and 0 V, respectively, depending on whether the antenna is normal, short-circuited, or disconnected. These values are values that can be sufficiently discriminated, and the state of the induction wire loop antenna 3 can be detected by reading the voltmeter.

Although the terminating resistor Ro of the induction loop antenna 3 is not absolutely necessary, the current in the normal state of the antenna is almost determined by the value of the terminating resistor Ro. Is preferred.

The antenna condition monitoring device 2 including the filter including the capacitor C and the coil L, the voltage source E, the series resistor Rs, and an antenna condition monitor (described later) for detecting the voltage of the resistor Rs is incorporated in the antenna controller 8. Have been.

FIG. 16 is a block diagram showing an antenna controller 8 including the antenna condition monitoring device. As shown in the figure, the antenna condition monitoring device 35 monitors the current of the voltage source E through a filter including a capacitor C and a coil L connected to the connection terminal of the induction wire loop antenna 3, and according to the current value, This is for determining whether the induction loop antenna 23 is normal, disconnected, or short-circuited. The monitoring signal indicating this judgment result is CPU2
Then, the operation confirmation display 36 connected to the CPU 24 displays an LED.

It should be noted that the normal, disconnection, and short-circuit states of the induction loop antenna are transmitted to the central management device 6, and the central management device 6 manages and grasps the status of each induction loop antenna and displays it on the CRT as necessary. If printing is performed by a printer, the state of each guide wire loop antenna can be grasped in a unified manner, so that the maintenance and operation of the system is of course streamlined.

Now, as shown in the figure, the CPU 24 is provided with a function check program 38 and a function check switch 39,
When the function check switch 39 is operated, the function check program 38 is loaded, and the state of the inductive loop antenna 3 detected by the antenna state monitor 35 is displayed on the operation confirmation display 36 as an LED lamp 361 or a digital digital display. It is displayed as 362. Therefore, the inspector can check whether the antenna condition monitoring device 2 is functioning.

According to FIG. 16, a reception level monitor 37 is provided. The reception level monitor 37 detects the presence or absence of transmission from the transmitter terminal 4.

If there is no transmission from transmitter terminal 4,
That is, when no voltage is induced in the induction loop antenna 3, the reception level monitor 37 cannot detect the intermediate frequency signal. At this time, the CPU 24 replies to the central management device 6 with the information to that effect included in the response signal.

When receiving the intermediate frequency signal by sequentially designating the antenna controller 8, the central management device 6 determines that the information indicating that there is no transmission from the transmitter terminal 4 is included in the response signal. The observation of the intermediate frequency signal from the controller 8 is skipped, and the intermediate frequency signal for the next antenna controller 8 is observed. If you do this,
Although the number of transmitter terminals is actually zero, it is possible to prevent a waste of time of performing long-time reception observation in the area, so that the entire reception observation time can be further reduced.

And when the function check switch 39 is operated,
The function check program 38 is loaded, and the status of the presence or absence of transmission from the transmitter terminal 4 detected by the reception level monitor 37 is also displayed on the operation confirmation display 36 by the LED lamp 361. Therefore, the inspector can check whether the reception level monitor 37 is functioning.

Note that the present invention is not limited to the above embodiment. For example, in the second embodiment, the antenna state monitor 35,
Although both the reception level monitors 37 are provided, it is not always necessary to provide them. The present invention may be implemented with only one of the antenna state monitor 35 and the reception level monitor 37. Various other design changes can be made without changing the gist of the present invention.

<Effects of the Invention> As described above, according to the entry / exit counter of the present invention, the guidance field generated from the transmitter terminal has a locality, so that the guidance line loop antenna installed in the area where the entrance is located. Induces voltage in linkage with only The central management device can identify the induction loop antenna in which the voltage has been induced, and specify the area where the induction loop antenna is installed as the existing area of the entrant.

Therefore, in a closed space such as an underground structure or a building, it is possible to accurately detect the area where the entrant is located without requiring the entrant to perform complicated work.

Further, since the function of the antenna controller can be checked on the side of the antenna controller, a large number of items can be checked easily in a short time.

[Brief description of the drawings]

FIG. 1 is a diagram showing an outline of an entry / exit counter of the present invention, FIG. 2 is a diagram showing an outline of a transmitter terminal, and FIG. 3 is a graph showing a distance attenuation characteristic of an inductive field output from the transmitter terminal. FIG. 4 is a diagram showing an outline of an entry / exit counter according to an embodiment of the present invention, FIG. 5 is a block diagram showing an embodiment of an antenna controller, and FIG. 6 is a polling output from a central management unit. FIG. 7 shows a format of a response signal output by the antenna controller, FIG. 8 shows a cross-sectional view of a road, and FIG. 9 shows an arrangement state of a guide wire loop antenna in the road. Fig. 10 illustrates the frequency characteristics of the spatial noise level (equivalent noise figure) up to several tens of MHz, which is standardized by CCIR. Fig. 11 shows the equivalent noise figure FIG. 12 is a graph showing frequency characteristics. FIG. 13 (a) is a perspective view showing an induction wire loop antenna in which ends are connected by resistors, and FIG. 13 (b) is a short-circuited end. FIG. 14 is a perspective view showing an induction wire loop antenna, FIG. 14 is a signal format of a modulation signal for modulating an AC magnetic field generated from a transmitter terminal, FIG. 15 is a diagram showing a circuit example of an antenna condition monitoring device, and FIG. FIG. 17 is a block diagram showing an antenna controller according to a second embodiment of the invention, and FIG. 17 is a diagram showing a conventional inbound / outbound counting device using an infrared counter. 1 ... closed space, 2 ... antenna condition monitoring device, 3 ...
... guide wire loop antenna, 4 ... transmitter terminal, 5
…… Signal transmission line, 6 …… Central management unit, 8 …… Antenna controller, 11 …… Polling signal line, 12 …… Response signal line, 24 …… CPU, 36 …… Operation confirmation display, 38 …… Function check program, 39 …… Function check switch, 41…
… Driver, 42 …… Transmit antenna

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yoshizo Shibano 1-3-1 Shimaya, Konohana-ku, Osaka-shi, Osaka Sumitomo Electric Industries, Ltd. Osaka Works (72) Inventor Seichi Higuchi Shimaya, Konohana-ku, Osaka-shi, Osaka 1-3-1, Sumitomo Electric Industries, Ltd., Osaka Works (72) Inventor Haruo Suzuki 1-3-1, Shimaya, Konohana-ku, Osaka-shi, Osaka Sumitomo Electric Industries, Ltd. Osaka Works (72) Inventor Yukio Nakayama Tokyo Nippon Telegraph and Telephone Corporation, 1-1-6 Uchisaiwai-cho, Chiyoda-ku, Tokyo (72) Inventor Tatsuro Imada Tatsuro 1-16-1 Uchisaiwaicho, Chiyoda-ku, Tokyo Nippon Telegraph and Telephone Corporation (72) Inventor Yukio Togo Ota, Tokyo 7-6-31 Omori-nishi-ku Sumitomo Opcom Co., Ltd. Examiner Tokio Goto (56) References JP-A-62-287727 (JP, A) JP-A-63-301399 (JP, A) JP-A-1-216629 (JP, A) JP-A-2-268529 (JP, A) JP-B-55-5077 (JP, B2) (58) Survey Field (Int.Cl. ⁶ , DB name) G06M 7/00-11/00 G08B 25/10

Claims (3)

(57) [Claims] An apparatus for detecting an occupant having a transmitter terminal in a closed space such as an underground structure or an inside of a building, wherein the transmitter terminal and the closed space are located in a space. An induction wire loop antenna that is installed so as to be substantially parallel to the road in each of the areas when divided vertically into a plurality of areas along the road, and detects an electromagnetic wave generated from the transmitter terminal; A central management device for identifying a region where an entrant is present by detecting a voltage induced in any of the induction wire loop antennas, wherein the transmitter terminal includes: a transmission antenna; And a driver for driving the transmitting antenna with an AC signal having a frequency f equal to or lower than the lowest frequency fc that can propagate the signal, and the induction loop antenna is induced by the induction loop antenna. An antenna controller for converting a signal voltage to an intermediate frequency signal is connected, and the central control device is connected to a plurality of antenna controllers via a common signal transmission line, and each antenna controller is Addresses are individually assigned, the signal transmission line is a polling signal line from which a polling signal specifying one of the addresses of the plurality of antenna controllers is sequentially derived from the central control device, and each antenna controller is It includes a response signal line for transmitting a response signal derived when a polling signal specifying its own address is received, and a terminal signal line for transmitting the intermediate frequency signal. A switch for permitting or prohibiting the intermediate frequency signal from being led out to the terminal signal line, and receiving the polling signal designating its own address, the antenna controller transmits the intermediate frequency signal to the terminal signal line. A switching controller for deriving a terminal signal line and, when receiving a polling signal designating an address other than its own address, performing switching control of a switch for disconnecting between the antenna controller and the terminal signal line; A function check switch for loading a function check program for checking at least one of the items (a) to (d) into the switching controller; (a) a power supply voltage value; and (b) an intermediate frequency signal conversion. (C) Self-address of antenna controller (d) Suspected including self-address of each antenna controller Receiving confirmation function for generating a polling signal and confirming whether or not to perform a predetermined operation when polling is performed by its own address. . 2. An antenna condition monitoring device for detecting disconnection / short-circuit of an induction wire loop antenna is mounted on said induction wire loop antenna, and detecting a disconnection / short-circuit condition of the induction wire loop antenna when a function check switch is operated. 2. The function of the antenna controller can be confirmed by the antenna controller.
An entry / exit counter as described. 3. The antenna controller according to claim 1, further comprising a detection circuit for constantly detecting a signal voltage induced in the induction wire loop antenna to detect the presence or absence of transmission from the transmitter terminal in each area. 2. The apparatus according to claim 1, wherein a detection level of the detection circuit can be confirmed by the antenna controller when operated.