JPS5953512B2 - Device for confirming the presence of people in buildings using leaky waveguide cables - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention can be used in shielded buildings such as underground malls, building premises, and tunnels where long-distance propagation of radio waves is not possible, or in buildings where sufficient line-of-sight cannot be obtained. The present invention relates to a personnel presence confirmation device that is capable of confirming the presence of personnel in a building and giving instructions such as appropriate evacuation guidance through wireless communication or the like.

In response to recent social demands, underground shopping streets have developed and skyscrapers have grown in large cities, and the total length of tunnels has increased significantly due to the spread of high-speed railways and expressways.

Since these buildings move or accommodate large numbers of people, communication equipment is essential for crime prevention, disaster prevention, and emergency evacuation commands in the event of a disaster or other emergency.

Portable mobile radios are mainly used for these so-called security communications, but all of the above-mentioned buildings (hereinafter referred to as underground malls, etc.) are so-called shielded buildings where radio waves cannot propagate over long distances. Because the area is divided into regions, the range over which mobile radios can communicate is significantly shortened, and it is often difficult to achieve the intended purpose.

In addition, these buildings have branching and crossing passageways, and in the event of a fire, smoke obstructs visibility, making it difficult to escape even when communicating via mobile radio. arise.

By the way, as shown in FIG. 3, it is being considered to install one leaky coaxial cable 20 in each of the divided sections A, B, C, and D of the passageway of the underground shopping mall 1, and to communicate with the transceiver 14. .

When the transceiver cable is moved along the leaky coaxial cable 20 in section C while maintaining a constant distance between the transceiver cables and the transmission output from the transceiver 14 is received by the leaky coaxial cable, the reception level becomes curve C in FIG. A curve that repeats fluctuations every small period as shown is obtained.

This variation is caused by interference coupling between waves emitted from a radiation source such as a slot provided in the cable's outer conductor and waves reflected from various objects in the underground passageway. This cannot be avoided as long as leaky coaxial cables are used.

By the way, when the transceiver 14 is at the point shown in FIG. 3, the transmission output of the transceiver 14 is in the section C.
In addition to the leaky coaxial cable in Section B, Section D, and Section A, the signal is also received by the leaky coaxial cable in Section B, Section D, and Section A.

That is, when the transceiver moves along section C of the passage, a reception output as shown by curve B in FIG. 4 is obtained from the leaky coaxial cables laid in sections B, D, and A.

Depending on the position of the transceiver 14, the minimum value of the received output level of the leaky coaxial cable in section C becomes smaller than the received output level of the leaky coaxial cable in section B (hereinafter section B will be taken as a representative), such as point P in the figure. , Q point, R point, etc., the reception level of the leaky coaxial cable in section B is higher than the reception level of the leaky coaxial cable in section C.

Therefore, if you try to confirm the presence of personnel simply by looking at the magnitude of the reception level, at points P, Q, R, etc. in the figure, it will appear as if the person is holding a transceiver, even though the transceiver is located in section C. This results in an erroneous determination that a pedestrian exists in section B.

The present invention enables appropriate evacuation after confirming the presence of pedestrians and other personnel in areas where sufficient line-of-sight cannot be obtained in the event of a fire in a shielded building where radio waves cannot propagate over long distances. For each section of a passage in a building that is divided into multiple sections that can give guidance instructions, multiple leaky waveguide cables are installed in parallel along the passage and terminated at one end with a terminating resistor. , a receiver having a means for encoding a signal connected to the other end of each of the plurality of leaky waveguide cables, and a logical sum connected to these receivers and combining the logical sums of the signals from each receiver. In addition to providing a circuit,
The present invention attempts to propose a personnel presence confirmation device using a leaky waveguide cable, characterized by comprising means for centrally monitoring the output of the OR circuit.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a plan view of one embodiment of the apparatus for confirming the presence of people in a building according to the present invention, and FIG. 2 is an explanatory diagram showing the state in which the embodiment of FIG. 1 is used.

In the figure, passage 1 of the building has multiple sections, A, B, C, D, etc., as indicated by broken lines in the figure.
..., etc., and within each section, two leaky coaxial cables 3 and 4 are laid in parallel and spaced apart along the ceiling side wall of the passage.

A terminating resistor 5 is installed at one end of the two leaky coaxial cables.
6 is connected, and the other end is connected to a connection unit 7.

The connection unit 7 includes a distribution coupler 8 for feeding power to the leaky coaxial cables 3 and 4, and a receiver 9 having means for encoding the outputs received by the leaky coaxial cables 3 and 4, respectively.
and a logical sum circuit 10 that synthesizes and transmits the logical sum of the outputs of the receiver 9.

Reference numeral 13 denotes a monitoring center for monitoring the occurrence of disasters, etc., and is equipped with an offshore central processing unit 11 and a wireless transmitter 12.

A case where a fire breaks out in the underground mall 1 will be explained as an example.

When the pedestrian 15 takes out the emergency communication transceiver 14 from a communication box (not shown) provided on the wall of the passageway 2, the power of the transceiver 14 is turned on and transmission begins.

After the radio waves transmitted from the transceiver 14 are captured by the leaky coaxial cables 3 and 4 provided in the passage,
It is encoded by the receiver 9.

This encoded signal is input to the OR circuit 10, and the combined output of the OR circuit 10 is sent out.

The outputs from each logical sum circuit 10 installed in each section of the passageway of the underground mall are centrally monitored at a monitoring center 13.

After the occurrence of a fire is detected by a fire detector (not shown), the central processing unit 11 displays on a display panel, etc., the presence or absence of personnel in each section based on the presence or absence of transmission from the transceiver from each section.

The monitoring center 13 closes fire shutters in unmanned sections, directs people to the shortest evacuation route in sections where personnel are present, directs traffic, and communicates instructions to the fire brigade to extinguish fires.

In the case of FIG. 2, an evacuation guidance command for pedestrians in section A is sent by radio transmitter 12, and power is supplied to leaky coaxial cables 3 and 4 via distribution coupler 8.

Transmitted through a leaky coaxial cable, the emitted radio waves are received by the transceiver 14 and the pedestrian 15 is sent to the monitoring center 10.
You can safely evacuate based on instructions from

Now, if a pedestrian 15 carrying a transceiver 14 moves along a path where leaky coaxial cables 3 and 4 are laid, the received voltage of each leaky coaxial cable 3 and 4 will be as shown in FIG. and the receiving voltage port.

These received voltages A and A are input to a receiver 9.9.

The receiver 9 has a preset determination reference level for determining the presence of personnel.

In other words, if the input voltage is above the judgment reference level, the receiver 9 indicates the presence of personnel, and if it is below, it indicates the absence of personnel.
It outputs the level.

With these settings, the output of each receiver will be as shown in Figure 6, I9.
It will be encoded as shown in the image.

The output of each receiver is a pedestrian 15 with a transceiver 14.
However, even if the judgment standard level is set high, there is a very small probability that the level will be O level at the same time because multiple leaky coaxial cables are installed. , therefore, this output is sent to the OR circuit 10
By inputting and synthesizing, the probability that the synthesized output will be 0 level becomes extremely small.

Therefore, the criterion level for determining the presence of personnel can be set high, and low reception outputs from other sections can be set to O level.

In addition, even if the pedestrian 15 carrying the transceiver 14 moves and the output drops from the level to 0, if the O level is not maintained for a certain period of time, it will not be determined that there is no personnel present, so that the presence of personnel will be mistakenly recognized as absent. There's nothing to do.

Furthermore, according to the device of the present invention, the received voltages of multiple leaky coaxial cables are encoded by the receiver, and the combined output is centrally monitored by the OR circuit, so that when the received voltages of multiple lines are directly combined, Since the received voltages have the same amplitude and opposite phase, etc., the output of the signal synthesizer disappears, and there is no possibility of erroneously confirming the presence of personnel.

Furthermore, multiple leaky coaxial cables are installed, the received voltage of each leaky coaxial cable is encoded by the receiver, and the combined output is centrally monitored by the OR circuit, so the judgment standard level of the receiver can be raised. The influence of low reception power from other sections can be removed, and errors will not occur in presence determination at the end of the section as shown in FIG.

As the leaky waveguide cable used in the present invention, in addition to a leaky coaxial cable, a cable having the functions of signal transmission and radiation at the same time, such as a leaky waveguide or a parallel two-wire cable, can be used.

In the embodiment of the invention illustrated in FIGS. 1 and 2,
We have shown a case in which the monitoring center confirms the presence of pedestrians when the pedestrian sends a message using a transceiver, and the transceiver receives an evacuation guidance command sent from the monitoring center using a leaky coaxial cable. After the monitoring center confirms the presence of a pedestrian by transmitting a signal using a simple ultra-high frequency oscillator for generating an emergency signal, the center directly issues an evacuation guidance command using a public address system. You can.

Buildings in the present invention include not only underground structures such as underground malls and tunnels described in the above embodiments, but also high-rise buildings and cabins and passageways of large ships.

In addition to the evacuation guidance described above, the present invention can also be applied to a system for displaying the location of important persons in buildings or security patrol shells, and has a wide range of applications.

[Brief explanation of the drawing]

Fig. 1 is a plan view of an underground mall showing one embodiment of the present invention;
The figure is an explanatory diagram showing the usage state of the embodiment of FIG. 1. Fig. 3 is a plan view of the area near the intersection of the underground mall, Fig. 4 is a graph showing fluctuations in the reception level in the longitudinal direction of the leaky coaxial cables installed in section C and section B in Fig. 3, and Fig. 5 is a graph showing the present invention. 6 is a graph showing the fluctuation of the reception level in the longitudinal direction of a plurality of leaky coaxial cables, and FIG. In the figure, A, B, C, D, E. F and G are multiple divided sections of underground shopping mall 1, 2 are underground shopping mall passages, and 3
, 4 is a leaky coaxial cable, 5°6 is a terminating resistor, 8 is a distribution coupler, 9 is a receiver, 10 is an OR circuit, and 13 is a monitoring center.

Claims (1)

[Claims] 1. For each section of a passage in a building that is divided into multiple sections, a plurality of leaky waveguide cables are installed in parallel along the passage and terminated at one end with a terminating resistor, and each of the plurality of A receiver having a means for encoding a signal connected to the other end of the leaky waveguide cable, and an OR circuit connected to these receivers and synthesizing the OR of signals from each receiver, A system for confirming the presence of personnel in a building using a leaky waveguide cable, characterized in that it includes means for centrally monitoring the output of the OR circuit.