JP3998333B2 - Buried life exploration device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a technique for searching for a life form confined in a collapsed building, accumulated rubble, earth and sand, snow (hereinafter referred to as sediment). Such a technique is particularly useful for finding buried survivors during disasters.
[0002]
[Prior art]
Insert a saddle-shaped antenna device with a structure in which both a small transmitting antenna and a receiving antenna are attached to the tip of the saddle-shaped support member into the deposit, and reflect the reflected wave of the microwave radiated from the transmitting antenna. By receiving the characteristics of this reflected wave, such as the phase change, by receiving it with the receiving antenna, the influence of the reflected wave (noise) from the surface of the deposit and surrounding moving objects is reduced, and the life of the buried creature There has already been proposed a method and apparatus for detecting minute displacements of the body surface accompanying breathing and heartbeat or movements of various parts of the body such as limbs, and thereby detecting the buried life form (Japanese Patent Application No. 8). -125475: see JP-A-9-304525).
[0003]
As a modification of this method, it is also possible to prepare a similar saddle-shaped transmitting antenna device and receiving antenna device separately, insert them into the deposit, and detect the living body according to the same principle as described above. In particular, the reliability of detection can be increased by using a plurality of at least one of the transmitting antenna tool and the receiving antenna tool (see Japanese Patent Application No. 9-158632: Japanese Patent Application Laid-Open No. 11-006874).
[0004]
The detection principle of these methods is to detect fluctuations in the amplitude or phase of the reflected wave. It is highly probable that it is due to the movement of the survivors, so the existence of buried survivors is estimated.
[0005]
[Problems to be solved by the invention]
However, even if there is no detection output indicating fluctuations in the amplitude or phase of the reflected wave, this does not necessarily mean that there is no buried survivor. This is because the radio wave characteristic of the radio wave path in the deposit from the transmitting antenna through the target area to the receiving antenna is unknown. In particular, in the case of a building collapsed due to an earthquake or the like, there are many cases where fairly large radio wave reflectors such as metal furniture and building parts are buried in various places. For example, if there is a radio wave reflector between the transmitting antenna and the surviving survivor, the emitted radio wave is reflected there and cannot reach the surviving survivor. The reflected wave cannot be received if there is a radio wave reflector between the buried survivor and the receiving antenna even if it reaches the person and is reflected there. In either case, the amplitude or phase of the reflected wave A detection output indicating fluctuations in the number cannot occur.
[0006]
Therefore, if it is possible to know the characteristics of the path of radio waves in the sediment from the transmitting antenna through the target area to the receiving antenna, it is possible to take measures and discover the buried survivor as much as possible. be able to.
One of the objects of the present invention is an embedded life form detecting apparatus of a type in which a bowl-shaped transmitting antenna tool and a receiving antenna tool are inserted into a deposit, and the inside of the deposit from the transmitting antenna to the receiving antenna through the target area. The purpose is to easily obtain information on the radio wave characteristics of a radio wave path.
[0007]
Another problem with such a type of buried survivor detection device is the mismatch of impedance matching between the antenna and the cable. When the antenna device is manufactured, impedance matching between the antenna and the cable is taken. However, in many cases, this antenna device is subjected to considerable rough handling. Therefore, when the cover (cone) of the antenna portion is broken or the joint portion between the antenna member and the support member is loosened, moisture enters from there. Corrosion will occur at the antenna or at the connection between the antenna and the cable. If this happens, impedance mismatch occurs between the antenna and the cable, and signal reflection occurs. As a result, the power of the transmitted radio wave decreases for the transmitting antenna, and the input power of the receiving circuit for the receiving antenna. Decrease.
[0008]
Another object of the present invention is to easily obtain information on impedance matching between an antenna and a cable in the antenna device of the above type.
[0009]
[Means for Solving the Problems]
In the present invention, a display device for displaying the intensity of a signal traveling from the antenna to the transmitter / receiver on the cable is provided at the rear end of the bowl-shaped antenna device. A circuit for generating a data signal representing the intensity of this signal may be built in the antenna device or provided outside. If this circuit is provided outside, the same antenna device can be used for both transmission and reception. The display device may be detachable.
[0010]
In the case of an antenna device dedicated to transmission, a circuit (for example, a directional coupler) that separates a signal traveling from the antenna to the transmitter / receiver from a signal in the opposite direction, and detects the intensity of the separated signal and outputs the output. A signal strength detection circuit supplied to the display device may be built in the antenna device.
[0011]
In the case of a reception-only antenna device, a circuit (for example, a distributor / synthesizer) that separates a part of the signal traveling from the antenna to the transmitter / receiver, and the intensity of the separated signal are detected and the output thereof is A signal strength detection circuit supplied to the display device may be built in the antenna device.
[0012]
Further, the separation circuit, the signal strength detection circuit, and the display device may be integrated into a unit that can be attached to and detached from the rear end portion of the antenna support member.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows an example of an antenna device according to the present invention, in which (a) is an overall external view, and (b) is a cross-sectional view of a tip portion. The basic structure of the transmitting antenna device and the receiving antenna device are the same. A microstrip antenna 3 covered with a plastic protective lid 2 is attached to the tip of a tube 1 as a stainless steel supporting member having a length of about 1.5 meters. A cable 4 connecting the vessels passes through the tube 1. A display unit 5 is attached to the rear end of the tube 1. The diameter of the portion consisting of the tube 1 and the circular lid 2 is about 7 centimeters at the thickest portion (the base of the circular lid). The length of the tube 1 should be at least 50 centimeters and the diameter of the thickest part should not exceed 15 centimeters. This antenna has a gentle directivity in the length direction of the antenna device.
[0014]
FIG. 2 shows details of the appearance of the display unit 5. A meter 7 is provided on the upper surface of the box 6, and a connecting pipe 8 for connecting to the pipe 1 of the antenna device is attached to one of the side faces. The outer diameter of the connecting pipe 8 can be inserted exactly into the rear end of the pipe 1 and is slightly smaller than the inner diameter of the pipe 1 so that it can be pulled out. Although not shown, a male and female cable connector for connecting a circuit in the box 6 and a cable in the pipe 1 is provided at the front end of the connecting pipe 8 and the rear end of the pipe 1. A cable connector for connection between the circuit in the box 6 and the cable 9 from the transmitter / receiver is provided on the side surface opposite to where the tube 8 is provided.
[0015]
FIG. 3 shows a circuit accommodated in the display unit for a transmitting antenna device. The directional coupler 10 separates the signal traveling from the antenna to the transmitter on the contrary from the signal transmitted from the transmitter to the antenna, and the separated signal (the signal traveling from the antenna to the transmitter) is amplified by the amplifier 11. Thereafter, the wave is detected by the detector 12, and the detection output is supplied to the meter 7. Power to the amplifier 11 is supplied from the battery 13. In the circuit of this example, the detector 12 is a simple diode detector, and since the display device is a moving coil type meter, it is not necessary to supply power to them. Also, power is supplied from the battery 13. Note that when the transmission output is sufficiently large, the amplifier 11 is not necessary, and therefore a power source for that purpose is also unnecessary, so that the battery can be removed from the display unit for the transmission antenna.
[0016]
FIG. 4 shows a circuit accommodated in the receiving antenna display unit. The distributor / synthesizer 14 separates a part of the signal traveling from the antenna to the receiver, and the separated signal is amplified by the amplifier 11 and then detected by the detector 12, and the detection output is supplied to the meter 7. Supplied. Power to the amplifier 11 is supplied from the battery 13. In the circuit of this example, the detector 12 is a simple diode detector and the display device is a moving coil type meter, as in the case of the display unit for the transmitting antenna device. If necessary depending on the type of the equipment, power is also supplied from the battery 13 to them.
[0017]
There may be many variations on the embodiments described above. First, the display unit may be fixed to the tube 1. Various changes can be made to the internal circuit of the display unit. In particular, the detector 12 and the meter 7 can be replaced by any other type of device as long as it is a means for detecting the signal strength and a means for displaying the result. For example, a digital display device can be used as the display means.
[0018]
Of the circuits shown in FIGS. 3 and 4, the portion excluding the meter 7 may be provided in the transceiver instead of being provided in the display unit. For example, in the case of the circuit of FIG. 3, it can be inserted between the final stage amplifier of the transmission circuit and the transmission terminal, and in the case of the circuit of FIG. 4, it is inserted between the first stage amplifier of the reception circuit and the reception terminal. can do.
[0019]
According to the present invention, in the case of a transmission antenna device, it is possible to know the state of reflection in the vicinity of the antenna on the transmission wave path. In other words, if the intensity of the reflected signal is very high, it may be estimated that a considerably large radio wave reflector exists in the transmission wave path very close to the transmission antenna. In this case, it is necessary to change the insertion position of the transmission antenna tool.
[0020]
In the case of a receiving antenna tool, information can be obtained about the state of the path of a radio wave from the transmitting antenna through the target area to the receiving antenna. For example, if the intensity of the received signal is very small, there may be a fairly large reflector on the transmitted wave path or somewhere on the reflected wave path. If the intensity of the received signal is abnormally high, the transmitting antenna and the receiving antenna are too close, so the transmitted wave has reached the receiving antenna directly, or is relatively close to the transmitting antenna on the path of the transmitted wave. There may be fairly large reflectors that reflect most of the transmitted wave in the direction of the receiving antenna. In these cases, it is desirable to change the insertion position of at least one of the transmission antenna and the reception antenna.
[0021]
Further, if the transmitting antenna device and the receiving antenna device according to the present invention are combined, the state of the radio wave path can be estimated more specifically, and measures can be easily taken. For example, when a large reflected wave is observed at the transmission antenna, first of all, it is necessary to change the insertion position of the transmission antenna tool. However, even though the reflected wave to the transmitting antenna is in the normal range, if the received signal at the receiving antenna is very small, there is a high possibility that there is a reflector on the path of the reflected wave. If the insertion position of the antenna tool is changed and improvement is not improved, it is recommended to change the insertion position of the transmission antenna tool.
[0022]
Furthermore, if the transmitter antenna is directed in a direction where there is no obvious reflector nearby, for example, in the air, and the intensity of the signal traveling from the antenna to the transceiver is examined, Since it is caused by reflection from the connection point between the antenna and the transmission cable, the degree of impedance mismatch between the antenna and the transmission cable can be known.
[0023]
For the receiving antenna tool, if the signal strength detection circuit is provided outside, for example, in the transmitter / receiver, the cable of the receiving antenna tool is connected to the transmitter side, and the antenna is the same as in the case of the transmitting antenna tool. By examining the intensity of the signal going from the transmitter to the transceiver, the degree of impedance mismatch between the antenna and the receiving cable can be known. When a detachable display unit is used, the same test as described above can be performed by connecting a display unit for a transmitting antenna tool to a receiving antenna tool.
[0024]
【The invention's effect】
As is apparent from the above description, according to the present invention, in a buried life form detection apparatus of a type in which a bowl-shaped transmission antenna device and a reception antenna device are inserted into a deposit, a reception antenna is transmitted from a transmission antenna through a target area. It is possible to easily obtain information on the radio wave characteristics of the radio wave path in the deposits leading to. Moreover, since the display device is provided on the antenna tool, an operator who inserts and moves the antenna tool can directly determine the situation on the spot, and accordingly, the appropriate insertion position of each antenna tool can be determined. Can be decided quickly.
[0025]
In addition, information on impedance matching between the antenna and the cable in the antenna device of the above type can be easily obtained.
[Brief description of the drawings]
1A and 1B show an example of an antenna device according to the present invention, in which FIG. 1A is an overall external view, and FIG.
FIG. 2 is an external view of a display unit.
FIG. 3 is a circuit diagram of a display unit for a transmitting antenna device.
FIG. 4 is a circuit diagram of a display unit for a receiving antenna device.
[Explanation of symbols]
1: Tube as support member 3: Antenna 4: Cable 5: Display unit 7: Meter 10: Directional coupler for separating the signal traveling from the antenna to the transmitter from the transmission signal 12: Detector 14: Reception from the antenna Distributor / synthesizer for separating part of the signal going to the mixer

Claims (2)

  An antenna attached to the front end of a bowl-shaped support member, a cable for connecting the antenna to a transmitter, and a signal traveling to the antenna on the cable at the rear end of the support member and the opposite direction The maximum dimension in the direction perpendicular to the length direction of the support member having a display device for detecting the intensity of the signal separated by the separation circuit and the output of the signal separated by the separation circuit and displaying the output thereof is 15 centimeters or less A transmitting antenna device, an antenna attached to the tip of a bowl-shaped support member, a cable for connecting the antenna to a receiver, and a rear end of the support member receiving the cable. In a direction perpendicular to the length direction of the support member, comprising a separation circuit for separating a part of the signal going to the container, and a display device for detecting the intensity of the signal separated by the separation circuit and displaying the output thereof Buried organism exploration device large dimensions, characterized in that it comprises both a receive antenna device is 15 centimeters or less.   The buried life form exploration device according to claim 1, wherein the display device is detachable from the support member.

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