JPH04102991A - Entering/leaving person counter - Google Patents

Abstract

PURPOSE:To specify the existence position of a facility inspecting person by arranging guide line loop antennas so that an AC magnetic field generated from a transmitter terminal is chained with only a guide line loop antenna set up inthe existence area of the inspector and induces voltage. CONSTITUTION:A magnetic field H generated from the transmitter terminal 4 is chained only with the guide line loop antenna 3 set up in the existence area of the inspector due to its locality and induces voltage in the antenna 3. The induced voltage signal is guided up to a central control unit 6 when an antennna controller 8 receives a poling signal, so that the device 6 can observe the induced voltage generated in each antenna 3. Thus, the central control unit 6 discriminates the antenna 3 from which voltage is induced and specifies the equipped area of the antenna 3 as the existence area of the inspector.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to an entry/exit counting device, and more specifically,
Relating to an entry/exit counting device capable of dividing a closed space such as a tunnel, underground structure, or inside a building into appropriate areas and detecting the presence of people entering each area. .

<Prior art and the problem to be solved by the invention> In tunnels, underground tunnels, basements, or closed spaces inside buildings where cables are laid, people enter and exit as needed to carry out work. It can be understood as a closed space system.

Working in a closed space can lead to serious accidents if a worker is left inside to observe the work from the outside. For this reason, it is extremely important to constantly observe and understand how many people or who is in which area of a closed space. Additionally, if an abnormal situation such as a fire occurs in the vicinity of a person entering the premises, it is important to inform the outside and take some measures.

For this reason, corporate entities that manage closed spaces such as tunnels have established management centers to observe and understand the number of people entering the premises and their identification numbers (IDs) in each area of the closed space.

That is, in the past, as shown in FIG. 17, a closed space 1 such as a tunnel is divided into appropriate areas, and infrared counters 21, 22, 23°, etc. are provided at the boundaries of each area, and the infrared counters 21, 22, 23°, etc. It counted the number of people passing by and processed the counts on each counter to manage the number of people in each area.

This system is economically advantageous because it uses a simple infrared counter, but human behavior is complex, and it requires multiple people to walk back and forth in front of a single counter many times. If you line up and cross the counter,
The number of people entering the campus in each area no longer matches the calculations.

In addition, counting errors occur even when the machine passes in front of the counter. If such an error occurs, the purpose of this system, which is to accurately grasp the number of people, will not be achieved.

Therefore, each person entering the campus is required to carry a wireless transmitting terminal, receiving antennas are installed in each area of the campus, and the location of the person entering the campus is estimated in the area corresponding to the receiving antenna that most strongly received the radio waves emitted by the wireless transmitting terminal. can also be considered.

However, with this method, it is thought that radio waves can be transmitted over long distances, with little attenuation in tunnels or tunnels, so the radio waves emitted from the wireless transmitting terminal owned by the person are received by many receiving antennas, and the It becomes difficult to determine the location.

It becomes even more difficult if radio waves or facing occur.

It is conceivable to notify the current location via voice from a wireless transmitter terminal, but it would be costly to prepare a large number of voice wireless transmitters, and it would require complicated work for those entering the premises, so it would be of little practical use.

The present invention has been made in view of the above problems, and its purpose is to tell the person entering the building whether he or she is in a closed space such as an underground structure or inside a building. To provide a crowd counting device that does not require complicated work and can accurately detect people.

As shown in Figure 1, the attendance counting device (means and operation for solving the above-mentioned problems) has the lowest frequency at which it emits radio waves to each person entering the premises. A transmitter terminal 4 that generates an alternating current magnetic field (induction field) at a frequency below fo is divided into a plurality of areas in a closed space such as a tunnel, and a guided wire loop antenna 3 is installed in each area. It is installed. Guide wire loop antenna 3
An antenna controller 8 that converts the signal voltage induced in the induction wire loop antenna 3 into an intermediate frequency signal is connected to the terminal of the antenna controller 8, and a common They are connected via a signal transmission line 5.

That is, it has a branch configuration in which a plurality of antenna controllers 8 are connected to the signal transmission line 5 by branch lines 9.

As shown in FIG. 2, the transmitter terminal 4 has a driver 41 that generates an alternating current with a frequency f below the antenna cutoff frequency fo, and an antenna 42.
An alternating current magnetic field H is generated from the antenna 42 by driving the antenna 42 at a frequency f below o. AC magnetic field H
is an induced field, and as shown in Figure 3, it has the characteristic that its intensity decreases rapidly with distance.

Signals are exchanged between the central management device 6 and the antenna controller 8 using polling signals.

For this reason, each antenna controller 8 is assigned an address, and the signal transmission line 5 is connected to the guide wire loop antenna 3.
In addition to the terminal signal line [3] for transmitting the aforementioned intermediate frequency signal obtained by converting the voltage induced by the voltage into an intermediate frequency, it includes a polling signal line [2] and a response signal line [2].

The polling signal line]]- transmits a polling signal that is supplied from the central management device 6 and specifies the address of one of the antenna controllers 8.

The response signal line 2 derives a response signal containing the antenna controller 8's own address when its own address matches the address in the polling signal.

The antenna controller 8 then uses a switch (not shown) or a switch that connects/cuts off the antenna controller 8 and the terminal signal line 13, and the address in the polling signal mentioned above matches its own address. Sometimes, the antenna controller and the terminal signal line 13 are connected by a switch, and when a bow link signal specifying an address other than the own address is received, the antenna controller and the terminal signal line 13 are connected. It is equipped with a switching controller that performs switching control of the switching device for shutting off.

Furthermore, the antenna controller 8 includes a function check switch that loads 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 self address 1 - Receipt confirmation function that confirms whether a predetermined operation is to be performed when polled for response] 0 An operation confirmation display that displays the result of the function check is provided.

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

Then, the central management device 6 can identify the guide wire loop antenna 3 in which the voltage is induced, and specify the area where the guide wire loop antenna 3 is installed as the area where the visitor is present.

Moreover, according to such a configuration, since the signal transmission line 5 is shared, the number of signal transmission lines can be reduced.

Furthermore, by operating a function check switch, a function check program can be activated to check the function of the antenna control unit on the antenna controller side.

<Example> Embodiments will be described in detail below with reference to the accompanying drawings showing examples.

FIG. 4 is a schematic diagram showing an example of a turnout counting device, in which a plurality of areas are set in opposite directions, and each area has parallel guiding wire loop antennas 3a, 3b3c, . . . (hereinafter referred to as "3").
) has been established. Each person entering the campus has their own transmitter terminal 4a.

4b, 4c, ... (hereinafter represented by the symbol "4"). The induction wire loop antenna 3 includes antenna controllers 8a, 8b, 8c that frequency convert the induced signal voltage into an intermediate frequency signal (hereinafter referred to as "intermediate frequency signal").
, - (hereinafter represented by the symbol "8") are connected.

Signal transmission between the central management device 6 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 the symbol "9"). With this configuration, signals are transmitted between the antenna controller 8 and the central management device 6 by applying a polling method.

Note that 10 is a branching device for branching the signal transmission line 5 to different observation areas.

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 designated by the polling signal, and a transmitter terminal. It has a terminal signal line 13 for transmitting the aforementioned intermediate frequency signal obtained by converting the signal voltage generated in the guide wire loop antenna 3 by the magnetic field from the guide wire loop antenna 3 into an intermediate frequency signal.

Addresses are individually assigned to the plurality of antenna controllers 8, and the central management device 6 derives a polling signal specifying the address corresponding to any one of the antenna controllers 8 to assign an address to any one of the antenna controllers 8. Controller 8
The antenna controller 8, which has been assigned the address in response to this, derives a response signal including its own address on the response signal line, and transmits the transmitter terminal 4 on the terminal signal line 13. An intermediate frequency signal corresponding to the signal from is derived.

FIG. 5 is a block diagram showing the configuration of the antenna controller 8. As shown in FIG. A polling signal from the polling signal line 11 is received by a receiver 22 via a coupler 21. The polling signal has a format as shown in FIG.

In other words, following the synchronization signal, the start bit (STX
), the address of the antenna controller 8 that is allowed to transmit, an error detection bit, and an end bit (PAD) are transmitted.

The polling signal received by the receiver 22 is given to the address determination circuit 23, and the address in the polling signal and the address assigned to the antenna controller 8 are assigned to the CPU.
(Central processing unit) 24 is compared with the address stored in the memory 25 connected to it. When the two addresses match, the CPU 24 gives the response signal creation circuit 26 the address stored in the memory 25 and other necessary data, and the response signal created based on this is sent from the transmitter 27. It is led out to the response signal line 12 via the coupler 28. The format of the response signal is 7th.
The synchronization signal, start bit (STX
), seven traces of the antenna controller 8, an error detection bit, and a termination bit (PAD).

The signal voltage transmitted through the induction wire loop antenna 3 is applied to the frequency converter 30 via two balloons. This frequency converter 30 mixes the signals given from the two balloons and the reference frequency signal from the local oscillator 3 and converts the signals from the two balloons into intermediate frequency signals. This intermediate frequency signal is further led out to the terminal signal line 13 from the coupler 34 via the switch 33 which is switched by the switch operation circuit 32 based on the output of the address determination circuit 23. The switch operation circuit 32 connects the frequency converter 30 and the coupler 34 in the switch 5 switch 33 only when the address determination circuit 23 detects whether the addresses match.

The antenna controller 8 is a device that includes a CPU 24 therein, and it is important in terms of maintenance and operation to be able to check the command control operation of the CPU 24 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 three function check switches so that the function check program 38 can be loaded when the function check switch 39 is operated. At this time, it would be a problem if the result of the operation by the function check program 38 is input to the central control unit 6 as a response signal, so the operations of the response signal generation circuit 26, transmitter 27, and coupler 28 are stopped during the function check. ing. Then, the result of the function check is displayed on the operation confirmation display 36, the LED lamp 361, or the numerical digital display 3.
62 so that the inspector can easily confirm the information.

[6] The contents of the check function of the function check program 38 are selected from at least the following items 1 to 2.

■ Confirming the power supply voltage value 0 Confirming the output level of the local oscillator 31 ■ Confirming the self-address of the antenna controller 8 ■ Confirming the pseudo polling signal receiving function Here, check the pseudo polling signal receiving function in (■) above. The addresses of all the antenna controllers 8 existing in the system (for example, 600, 601, 602, 603, . . . , 66 are group addresses) are stored in the attached memory of the check program 38, and these addresses (600, 600, 66 are group addresses) are stored at the time of check. 801, 602, 603,..., 6)
The CPU 24 sequentially creates a pseudo polling signal containing
0) or when group polling is performed using a group address (for example, 6), it is checked whether a predetermined operation is to be performed.

FIG. 8 is a sectional view of the tunnel, and the width of the tunnel is indicated by W. Cutoff wavelength λC when the tunnel is viewed as a waveguide
can be approximated by λc = 2W, so the cutoff frequency fc at which electromagnetic waves propagate is f c = c / 2 W
(c is the speed of light) ・■. The transmission frequency f of the transmitter terminal 4 is of course selected to be lower than the lowest frequency fo that allows radio waves to be radiated from the antenna, as described above, and is also selected to be cut in order to eliminate the propagation of electromagnetic waves in the opposite direction. The frequency is also selected to be smaller than the off frequency fC (in this example, fc <
fo).

If the guide wire loop antenna 3 is to receive an alternating magnetic field, it may be installed at a position corresponding to the shape of the tunnel. For example, it may be installed along the ceiling of a tunnel-like tunnel as shown in FIG. 9(a), or it may be installed along both side walls as shown in FIG. 9(b). As shown in (c) of the same figure, it may be installed along the bottom surface of the roof (Q), or it may be installed along one side wall as shown in (d) of the same figure. In particular, a position close to the bottom as shown in FIG. 4(c) is preferable because even if a person holding the transmitter terminal falls in the event of an accident, it can be reliably detected.

Figure 10 shows the frequency characteristics of the spatial noise level (equivalent noise figure) up to several tens of MHz, which is the CCIR standard (in the figure, A is a business area, B is a residential area, and C
indicates a rural area, and D indicates a quiet rural area. C.C.I.R.
(See C Small R1-258-4). FIG. 11 shows the frequency characteristics of the equivalent noise figure actually measured in the actual direction of the winding, and the noise becomes lower as the frequency increases. Therefore, in order to reduce the influence of urban noise, it is preferable to choose the frequency f to be as high as possible within a smaller range than fC.

Furthermore, in order to reduce the influence of noise, it is also important that the magnetic field is detected as efficiently as possible by the guide wire loop antenna 3. Figure 12 is a model for calculating reception efficiency, with the spacing of the parallel induction wire loop antenna 3 being set to 2.
D, the wire diameter is 2 r %, and the distance from the center of the parallel induction wire loop antenna 3 to the transmitter terminal 4 is X.

The coupling coefficient C [d B] between the guide wire loop antenna and the transmitter terminal is as follows, where ω is the angular frequency and A is a predetermined coefficient. From this equation, it can be seen that the coupling coefficient C increases in proportion to the square of the frequency, so from this point also the frequency f
is preferably higher than fc within a smaller range.

Next, specific guidelines for selecting the frequency f will be explained.

Assume a tunnel with width W shown in Figure 8. The force/soto-off frequency is calculated using the formula (■), and since radio waves no longer propagate below this frequency, the only electromagnetic waves that exist are local induced fields. fc
The length of the tunnel at the following frequency f and the attenuation constant of the electromagnetic field in the direction are approximated by adopting the waveguide theory as follows: a [dB/ml= 0.1.819 f [MHxl
It is estimated that (f'o#)2-1...■.

If the tunnel width W = 5 m, fc = 3 from formula 0.
0 MHz, but with some margin, f=20M
Choose Hz. From equation (2), the damping coefficient α=4 dB/m can be obtained. According to this, if you are 10m away, it will be 40dB, 2
If the distance is 0 m, the attenuation will be 80 dB, so 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 approximately equal to the characteristic impedance of the antenna (see FIG. 13(a)).

For example, if the frequency f is 20 MHz, the wavelength will be 15 m. The length of the induction wire loop antenna is 100m.
In this case, the length of the loop antenna becomes sufficiently long compared to the wavelength. In such a case, if a conductor is short-circuited instead of the resistor Ro, the coupling degree C between the inductive wire loop antenna and the transmitter terminal will change the wave at every 1/2 wavelength, as shown in Fig. 13(b). It becomes a standing wave shape. Therefore, when the position of the transmitter terminal 4 comes to the position of the trough of the standing wave, it is no longer coupled to the guide wire loop antenna.

Therefore, as shown in Fig. 13(a), the terminal end of the inductive wire loop antenna is connected to a resistor R approximately equal to its characteristic impedance.
When connected at 0, the degree of coupling C between the guide wire loop antenna and the transmitter terminal becomes almost uniform at any position, and the transmitter terminal can be detected at any position.

This attendance counting device has an identification number (hereinafter referred to as rlDJ) in the transmitter terminal 4, and is designed to not only detect the presence of people entering the premises, but also individually identify them. .

Figure 14 shows the format of the magnetic field modulation signal generated from the transmitter terminal 4, which includes a preamble, a synchronization bit, a start bit (STX), an ID bit indicating the affiliation and number of the person entering the premises, and an error detection bit. , termination bit (PAD). In the central management device 6, by demodulating each AC voltage signal received through the signal line 5, decoding and detecting the ID bits contained therein, it is possible to determine the affiliation of the person entering the premises and each individual person.

Table 1 shows each area A, B, and
C, shows the number of people entering the campus and the defle of IDs (001,,002,003,-.) of the people entering the area. (Margin below) Table 1 Next, a second example will be described.

The guide wire loop antenna 3 is an important piece of equipment for detecting the presence of the transmitter terminal 4, so if it is disconnected or short-circuited, it will become impossible to detect people entering the premises. However, since the guide wire loop antenna 3 is usually installed over a wide area, it is not easy to closely examine its damaged state. Therefore, by installing the antenna condition monitoring device 2 as in the present invention, the inspector can easily find out whether the antenna is short-circuited, damaged, etc. while looking around inside the closed space 1.

The configuration of the antenna condition monitoring device 2 will be described below. 1st
As shown in FIG. 5, a filter consisting of a coil of a capacitor C1 connected near the connection terminal 3 of the induction wire loop antenna 3, a voltage source E, and a series resistor R3 can be seen. The voltage across the series resistor R8 can be measured externally using a voltmeter V. Of course, the voltmeter (2) may be incorporated into the antenna condition monitoring device 2.

The filter passes the signal of the transmission frequency f induced in the guide wire loop antenna 3 to the connection terminal 3], or
The current flowing from the voltage source E (hereinafter referred to as "test current") is cut off so that it does not flow into the connection terminal 31. Therefore, when viewed from the guide wire loop antenna 3, the filter does not become a load for the signal of frequency f.

The test current flowing from the voltage source E flows unless the induction wire antenna 3 is disconnected, and its value It is equal to the voltage E.
It is determined by the resistance r of the 1-guide wire loop antenna 3, the series resistance R3, and the terminating resistance Ro of the guide wire loop antenna 3 (described later).

■t = E Ro+r+Rs Therefore, the voltage V across the series resistor Rs is v ==
RS ERo+r+Rs=Rs ERo+Rs. Here, it is assumed that the resistance r is sufficiently smaller than the resistance Rs.

If the induction wire loop antenna 3 is disconnected, the current Ii will not flow, so ①=0.

When the guide wire loop antenna 3 is short-circuited, it becomes V-R8E (E r+Rs) instead of Ro-〇.

E=5V, Rs=500Ω, Ro=600Ω,
Taking the numerical example of r' and 0, if the antenna is normal, v = 2,3V, and if the antenna is short-circuited, it will be V#5V. Therefore, depending on whether the antenna is normal, short-circuited, or disconnected, the measured values of the voltmeter V will be 2°3V, 5V, and 5V, respectively.
It becomes 0 ■. These values are values that can be sufficiently distinguished, and the state of the guide wire loop antenna 3 can be detected by reading the voltmeter V.

Isn't the terminating resistor RO of the above-mentioned inductive wire loop antenna 3 absolutely necessary?The value of the terminating resistor Ro almost determines the current in the normal state of the antenna, so it is necessary to detect the state of the inductive wire loop antenna 3. It would be better if there were.

An antenna condition monitoring device 2 consisting of a filter consisting of the capacitor C1 coil L, a voltage source E, a series resistor R8, and an antenna condition monitor (described later) that detects the voltage of the resistor RS is incorporated into the antenna controller 8. ing.

FIG. 16 is a block diagram showing the antenna controller 8 including this 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 consisting of a capacitor C1 coil connected to the connection terminal of the induction wire loop antenna 3, and depending on the current value, This determines whether the wire loop antenna 3 is normal, disconnected, or short-circuited. The monitoring signal representing this judgment result is C
It enters the PU 24 and is displayed by the operation confirmation display 36 connected to the CPU 24 using an LED.

In addition, the normality, disconnection, and short circuit status of the guide wire loop antenna is transmitted to the central management device 6, and the central management device 6
By managing and grasping the status of each guiding wire loop antenna and displaying it on a CRT or printing it out on a printer as necessary, you can centrally understand the status of each guiding wire loop antenna, so the system can be improved. It goes without saying that maintenance and operation will be streamlined.

Now, as shown in the figure, the CPU 24 is provided with a function check program 38 and three function check switches, and when the function check switch 39 is operated, the function check program 38 is loaded and detected by the antenna status monitoring device 35. The current state of the guided wire loop antenna 3 is displayed on the operation confirmation display 36 with the LED lamp 36] or on the numeric digital display 362. Therefore, the inspector can check whether the antenna condition monitoring device 2 is functioning or not.

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

When there is no transmission from the transmitter terminal 4, that is, when no voltage is induced in the induction wire loop antenna 3, the reception level monitor 37 cannot detect the intermediate frequency signal. At this time, the CPU 24
information to that effect is included in the response signal and sent back.

When the central management device 6 sequentially designates the antenna controllers 8 to receive the intermediate frequency signal, if the response signal includes information indicating that there is no transmission from the transmitter terminal 4, the central management device 6 selects the antenna controller 8 to receive the intermediate frequency signal. 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. In this way, it is possible to prevent the waste of time of conducting long reception observation for the relevant area even though the number of transmitter terminals is actually zero, which further reduces the overall reception observation time. be able to.

And when I operated the three function check switches,
The function check program 38 is loaded, and 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 with an LED lamp 361. Therefore, the inspector can check whether the reception level monitor 37 is functioning or not.

Note that the present invention is not limited to the above embodiments. For example, in the second embodiment, the antenna condition monitor 35,
Although both the receiving level monitor 37 and the receiving level monitor 37 were provided, it is not necessary to provide both. The present invention may be implemented using only one of the antenna condition monitor 35 and reception level monitor 37. Various design changes can be made without changing the gist of the invention.

<Effects of the Invention> As described above, according to the people counting device of the present invention, the alternating current magnetic field H generated from the transmitter terminal, due to its locality, can be applied to the guide wire installed in the area where the visitors are located. Induces voltage by interlinking only with the loop antenna. The central management unit can identify the guided wire loop antenna where the voltage is induced, and specify the area where the guided wire loop antenna is installed as the area where the visitor is present.

Therefore, in a closed space such as an underground structure or inside a building, it is possible to accurately detect whether the person is in the same area as the person entering the building without requiring the person entering the building to perform complicated operations.

Furthermore, since the function of the antenna controller can be checked on the antenna controller side, a large number of items 1" can be checked easily and in a short time.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing an outline of the 51-person device of the present invention, Fig. 2 is a diagram showing an outline of the transmitter terminal, and Fig. 3 is a diagram showing the distance attenuation characteristics of the induced field output from the transmitter terminal. 4 is a diagram showing an outline of a crowd counting device which is an embodiment of the present invention, FIG. 5 is a block diagram showing an embodiment of an antenna controller, and FIG. 6 is a diagram showing a central management device. Figure 7 shows the format of the polling signal output, Figure 7 shows the format of the response signal output from the antenna controller, Figure 8 is a cross-sectional view of the tunnel, Figure 9 shows the guide wire loop antenna in the opposite direction. A diagram illustrating the arrangement state, FIG.
Figure 11 shows the frequency characteristics of the equivalent noise figure actually measured in the opposite direction. Figure 12 shows the transmitter terminal and the inductor. Fig. 13(a) is a perspective view showing the inductive wire loop antenna with the terminal ends connected with a resistor; Fig. 13(b) is the inductive wire loop antenna with the terminal ends short-circuited. FIG. 14 is a signal format of a modulation signal that modulates an alternating magnetic field generated from a transmitter terminal; FIG. 5 is a diagram showing an example of a circuit of an antenna condition monitoring device; FIG. FIG. 17 is a diagram showing a conventional crowd counting device using an infrared counter. 1. Closed space, 2. Antenna condition monitoring device, 3.
・Guiding wire loop antenna, 4... transmitter terminal,
5...Signal transmission line, 6...Central management device, 8...Antenna controller, 11 Baulink signal line, ]-2-Response signal line, 24-CPU, 36...Operation confirmation display, 38...Function check program, 39 Function check switch, 41...Driver, 42.Transmission antenna Patent applicant Sumitomo Electric Industries, Ltd. Patent applicant Nippon Telegraph and Telephone Corporation Patent applicant Sumiden Ofcom Co., Ltd. Toha e-bin → Yado Fumoto 8 Dp p Pilgrimage Old model Mimi 1 Tofu Hikijosun no l7/ + Toz 7) Carved N Sho 1110 Connected to the 4 suns of the monks - Sunsun Tohachi → (lJI → Include Fu mo Ha Ok chant (To) Navy blue
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Claims (1)

[Claims] 1. A person who enters a closed space such as an underground structure or inside a building is given a transmitter terminal, the closed space is divided into a plurality of areas, and each area is , a guide wire loop antenna is installed to detect the alternating current magnetic field generated from the transmitter terminal, and the voltage induced in one of the guide wire loop antennas is detected via the signal transmission line to detect the presence of a person entering the premises. The transmitter terminal includes a central management device that specifies an area, and the transmitter terminal has a transmitting antenna and a frequency f that is lower than the lowest frequency fo that can emit radio waves from the transmitting antenna.
and a driver for driving the transmitting antenna with an alternating current signal, and an antenna controller for converting the signal voltage induced in the guide wire loop antenna into an intermediate frequency signal is connected to the guide wire loop antenna. , The central management device is connected to multiple antenna controllers via a common signal transmission line, and each antenna controller is individually assigned an address. A polling signal line through which a polling signal specifying the address of one of the plurality of antenna controllers is sequentially derived from the device, and a response signal derived when each antenna controller receives a polling signal specifying its own address. and a terminal signal line for transmitting the intermediate frequency signal; When the antenna controller receives a polling signal specifying its own address, it outputs the intermediate frequency signal to the terminal signal line, and when it receives a polling signal specifying an address other than its own address, it outputs the intermediate frequency signal to the antenna controller. A switching controller that performs switching control of the switching device that cuts off the connection with the terminal signal line, and a function check program that performs a functional check of at least one of the following items (a) to (d). (a) Power supply voltage value (b) Output level of local oscillator for intermediate frequency signal conversion (c) Self-address of antenna controller (d) Self-address of each antenna controller generation of a pseudo-polling signal including the generation of a pseudo polling signal, and a reception confirmation function for confirming whether or not a predetermined operation is performed when polled by the user's own address; and an operation confirmation display for displaying the result of the function check. Counting device. 2. The above guide wire loop antenna is equipped with an antenna condition monitoring device that detects disconnections and short circuits in the guide wire loop antenna, and when the function check switch is operated, the function to detect disconnections and short circuits in the guide wire loop antenna is activated. 2. The entry/exit counting device according to claim 1, wherein operation can be confirmed by said antenna controller. 3. The antenna controller has a detection circuit that constantly detects the signal voltage induced in the induction wire loop antenna to detect the presence or absence of transmission from the transmitter terminal in each area, and when the function check switch is operated. 2. The entrance/exit counting device according to claim 1, wherein the detection level by the detection circuit can be confirmed by the antenna controller.