JP4046274B2 - Intruder and obstacle detection device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an intruder and an obstacle detection device that specifies the position of an intruder or an obstacle by radiating radio waves from a leaking cable.
[0002]
[Prior art]
Conventionally, a radio wave having a specific frequency radiated from a transmitter side leakage cable and reflected or blocked by an intruder or an obstacle, and the intensity of the received signal is changed again to the receiver via the reception side leakage cable. Based on the delay time to return, the distance is calculated from the propagation speed of the radio wave, and the position of the intruder or the obstacle in the direction of laying the leaking cable is specified.
[0003]
Also, the closer to the receiving side leakage cable, the stronger the change in the received signal due to the influence of the intruder or obstacle. By replacing the receiving side and transmitting side leakage cables, the intruder or obstacle becomes the receiving side leakage cable. Or close to the transmission-side leakage cable (see, for example, Patent Document 1).
[0004]
[Patent Document 1]
Japanese Patent Laid-Open No. 10-95338
[Problems to be solved by the invention]
In such a conventional technique, the position of the intruder or the obstacle can be specified only by the distance in the laying direction of the leaking cable, and the two-dimensional position (position on the plane) cannot be specified. There was a problem.
[0006]
Furthermore, it is only possible to determine whether the position to the intruder or the obstacle is close to the receiving side leakage cable or the transmission side leakage cable by switching the transmission side and the reception side and comparing the reception intensity. In addition, the two-dimensional position could not be specified.
[0007]
In order to eliminate the above-mentioned problems, the present invention uses a radio wave of a plurality of frequencies, or changes the transmission side and the reception side, so that the distance to the intruder or obstacle in the direction of the leakage cable Intrusions that can not only measure the vertical distance from the leaking cable to the intruder or obstacle, and therefore identify the location on the plane of the intruder or obstacle sandwiched by the leaking cable It is an object to provide a person and an obstacle detection device.
[0008]
[Means for Solving the Problems]
To achieve the above object, an intruder and obstacle detection apparatus according to the present invention, the sender and receiver leaking cables in parallel laid, is connected to one end of the transmission-side leakage cable, a different radio frequencies A transmitter capable of transmitting and an end of the receiving side leakage cable on the same side as one end of the transmitting side leakage cable, radiated from the transmission side leakage cable and returned through the reception side leakage cable; A receiver for receiving the received radio wave, and a delay time measuring instrument for measuring a delay time until the radio wave transmitted from the transmitter is received by the receiver through the transmission side leakage cable and the reception side leakage cable with the door, the delay time measuring device transmits a first radio and a second radio wave having different frequencies from the transmitter, wherein the radiation angle depending on the frequency different from the first radio wave first Of radio waves to each of the delay time until received by the receiver is measured by reflection or blocked propagation path by an intruder or an obstacle, a distance between the receiving-side leak cable and the transmitting side leakage cable, radio wave speed , in the emission angle, and the two-dimensional plane including the transmission-side leakage cable and the receiving leaky cable based on the delay time, it is characterized in identifying the location of the intruder or obstacles.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the accompanying drawings.
[0010]
Embodiment 1 FIG.
FIG. 1 is a block diagram showing a schematic configuration of an intruder and obstacle detection device according to Embodiment 1 of the present invention. In this figure, the delay time measuring device 1 measures the delay time of the radio wave until the radio wave transmitted from the transmitter 2 is received by the receiver 3 through the propagation path blocked by the intruder or obstacle. Is. That is, the radio wave transmitted from the transmitter 2 passes through the transmission side leakage cable 4 and is transmitted to the reception side leakage cable 5 arranged in parallel to the transmission side leakage cable 4. The transmission time is measured by the delay time measuring device 1.
Here, when a radio wave having a frequency different from the delay time is transmitted from the transmitter 2, it indicates a time difference in transmission time until the receiver 3 receives the radio wave.
[0011]
By the way, since the angle at which the radio wave transmitted from the transmitter 2 is radiated from the transmission side leakage cable 4 to the reception side leakage cable 5 varies depending on the frequency of the radio wave, the length of the propagation path from the transmitter 2 to the receiver 3 is increased. Therefore, the delay time varies depending on the frequency. The delay time varies depending on the frequency.
[0012]
As shown in FIG. 2, the radiation angle determined by a certain frequency of the radio wave radiated from the transmission-side leakage cable 4 (the angle of the radiated radio wave with respect to the axis of the transmission-side leakage cable 4) is θ1, and an intruder or obstacle Let t1 be the delay time in the propagation path (A → B → D → F) reflected or blocked by. Next, the transmission path (A → C → E → F) is set in the same manner by changing the frequency to a frequency different from the previous one, and transmitting the transmitter 2 and radiating from the transmitting side leakage cable 4 with θ2 as the angle of the radio wave. The delay time is measured and is set as t2. The distance between the receiving side and transmitting side leakage cables 4 and 5 is h, the radio wave velocity is v, the distance from the receiver 3 or the transmitter 2 to the intruder or obstacle is x, and the transmission of the leakage cable is performed. If the distance from the side (the transmitting side leakage cable 4) is y, the two-dimensional (plane) coordinates (x, y) of the intruder or obstacle are
x = [v (tanθ2 ・ t2-tanθ1 ・ t1) -h {(1 / cosθ2)-(1 / cosθ1)}] / 2 (tanθ2-tanθ1)
y = v (t1-t2) / 2 {(1 / tanθ1)-(1 / tanθ2)} + (h / 2) [1-{(1 / sinθ1)-(1 / sinθ2)} / {(1 / tanθ1)-(1 / tanθ2)}]
The position in two dimensions can be specified.
[0013]
As described above, according to the intruder and obstacle detection device according to the first embodiment, the two-dimensional position of the intruder or the obstacle can be detected on the plane sandwiched between the leakage cables. effective.
That is, by changing the frequency of the radio wave radiated from the transmitter 2, the radiation angle from the leakage cable changes, and the propagation path changes due to the difference in the radiation angle, resulting in a difference in delay time. Even if the distance in the direction parallel to the leakage cable (the distance in the x-axis direction) is the same, the distance in the vertical direction from the transmission-side leakage cable 4 (the distance in the y-axis direction that is perpendicular to the x-axis direction) ), A difference in radio wave propagation delay time appears by changing the frequency, and this can be used to identify the distance to the intruder or obstacle in the y-axis direction of the leaked cable, and therefore The position in two dimensions can be specified.
[0014]
Embodiment 2. FIG.
FIG. 3 is a block diagram showing a schematic configuration of an intruder and obstacle detection device according to Embodiment 2 of the present invention, and FIG. 4 is a diagram for explaining the operation thereof.
As shown in FIG. 3, the configuration of the second embodiment is such that in FIG. 1, the transmitter 2 and the receiver 3 are replaced with the first transmitter / receiver 2A and the second transmitter / receiver 3A, respectively, so that the transmitter / receiver function is provided. Except for this point, the second embodiment is substantially the same as the first embodiment.
[0015]
In the second embodiment, instead of changing the frequency of the radio wave transmitted from the transmitter 2 as in the first embodiment, the transmitter 2 is changed to the first transmitter / receiver 2A and the receiver 3 is changed to the second transmitter / receiver. Instead of 3A, the first and second transceivers 2A and 3A alternately transmit radio waves of the same frequency and pass through a pair of leaky cables 4 and 5 and received by the other of the first and second transceivers. The delay time until measurement is measured by the delay time measuring device 1. Also in this case, the propagation path length of the radio wave from the first transceiver 2A to the second transceiver 3A and the propagation path length of the radio wave from the second transceiver 3A to the first transceiver 2A are a pair of leaks. Since it differs depending on the positions of intruders and obstacles existing between the cables 4 and 5, the delay time is also different.
[0016]
In FIG. 4, the radiation angle at the frequency of the radiated radio wave is θ, the delay time of the propagation path ((A → C → E → F) before switching between transmission and reception is t1, and the propagation path after switching (F → D). → B → A) t2 is the delay time, h is the distance between the cables 4 and 5, and v is the velocity of the radio wave. The receiver (first transmitter / receiver) 2A or the transmitter (second If the distance from the transmitter / receiver) 3A to the intruder or obstacle is x and the distance from the transmission side of the leaked cable is y, the two-dimensional (plane) coordinates (x, y) of the intruder or obstacle are
x = (v / 4) (t1 + t2)-(h / 2) (cosθ / sin ² θ)
y = (v / 4) tanθ ・ (t1-t2) + (h / 2)
Therefore, the position of the intruder or the obstacle in two dimensions can be specified.
[0017]
In the above description, in order to easily explain that the position can be specified on the x and y planes in terms of geometry, the propagation velocity of the radio wave in the leakage cables 4 and 5 is equal to that in the space, and the velocity v is calculated. However, in the actual leakage cables 4 and 5, the radio wave propagation speed in the leakage cables 4 and 5 determined by the material may be different from the radio wave propagation speed in space. Even in this case, since it can be reflected in the propagation path length in the leakage cables 4 and 5 described in FIG. 2 and FIG. 3, it goes without saying that the position of the obstacle or the intruder can be specified similarly. Further, in order to obtain a difference in the propagation path length of the radio wave, a frequency whose radiation angle θ from the leakage cables 4 and 5 is not 90 degrees is used.
[0018]
Embodiment 3 FIG.
In the second embodiment, the positions of intruders and obstacles existing between the pair of leaking cables 4 and 5 are specified by alternately transmitting radio waves of the same frequency from the first and second transceivers. 1, in the intruder and obstacle detection apparatus configured as shown in FIG. 1, a pair of transmitter 2 and receiver 3 and a pair of leakage cables 4, 5 are paired with transmitter 2 and receiver 3. A switch for simultaneously switching the connection with the leaking cables 4 and 5 is provided. With this switch, the connection between the transmitter 2 and the receiver 3 and the pair of leaking cables 4 and 5 is switched at the same time. The delay time measuring device 1 may measure the delay time until the radio waves having the same frequency are alternately transmitted to the pair of leaking cables 4 and 5 and received by the receiver 3.
[0019]
As described above, according to the intruder and the obstacle detection device according to the second and third embodiments, one of the leaks can be obtained by radiating radio waves of the same frequency by switching the reception side and the transmission side of the leakage cable. Since there is a difference in the propagation path depending on the distance in the y-axis direction from the cable to the intruder or the obstacle, a difference occurs in the delay time of the radio wave propagation. Therefore, as in the first embodiment, this delay time difference is used. Thus, the distance to the intruder or the obstacle in the y-axis direction of the leakage cable can be specified, and therefore the position in two dimensions can be specified.
[0020]
【The invention's effect】
As described above, according to the present invention, there is an effect that the two-dimensional position of an intruder or an obstacle can be detected on a plane sandwiched between leaking cables.
That is, by changing the frequency of the radio wave radiated from the transmitter, the radiation angle from the leakage cable changes, the propagation path changes due to the difference in the radiation angle, and the delay time varies, so the location of the intruder or obstacle is Even if the distance in the direction parallel to the leaky cable (distance in the x-axis direction) is the same, the delay in radio wave propagation by changing the frequency depending on the distance in the vertical direction (distance in the y-axis direction) from the transmission-side leaky cable Since it appears as a time difference, this can be used to identify the distance to the intruder or obstacle in the y-axis direction of the leaked cable, and thus to identify the position in two dimensions.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a schematic configuration of an intruder and obstacle detection device according to Embodiment 1 of the present invention.
FIG. 2 is an explanatory diagram when position detection is performed by changing a frequency according to the first embodiment of the present invention.
FIG. 3 is a block diagram illustrating a schematic configuration of an intruder and obstacle detection device according to a second embodiment of the present invention.
FIG. 4 is an explanatory diagram when performing position detection by switching between a transmission side and a reception side according to Embodiment 2 of the present invention;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Delay time measuring device, 2 transmitter, 2A 1st transmitter / receiver, 3 receiver, 3A 2nd transmitter / receiver, 4 (transmission side) leakage cable, 5 (reception side) leakage cable.

Claims (4)

A transmitting side and a receiving side leakage cable laid in parallel;
A transmitter connected to one end of the transmitting-side leakage cable and capable of transmitting radio waves having different frequencies;
A receiver connected to an end of the receiving side leakage cable on the same side as one end of the transmitting side leakage cable, and receiving a radio wave radiated from the transmitting side leakage cable and returned through the receiving side leakage cable When,
A delay time measuring device that measures a delay time until the radio wave transmitted from the transmitter is received by the receiver through the transmitting side leakage cable and the receiving side leakage cable, and
The delay time measuring device transmits a first radio wave and a second radio wave having different frequencies from the transmitter, and the first radio wave and the second radio wave having different radiation angles depending on the frequency are intruders. or each of the delay time until received at the receiver is measured by reflection or blocked propagation path by the obstacle, the distance between the transmitting side leakage cable and receiving leaky cable, radio wave speed, the emission angle, and the delay time in the two-dimensional plane including the transmission-side leakage cable and the receiving leaky cable based on an intruder and obstacle detection apparatus characterized by specifying the location of the intruder or obstacles. A pair of leaky cables laid in parallel;
A first transceiver connected to one end of the leakage cable;
A second transceiver connected to the other end of the leaky cable on the same end as the one end of the one leaky cable;
Delay time measurement for measuring a delay time until a radio wave transmitted from one of the first and second transceivers is received by the other of the first and second transceivers through the pair of leakage cables. Equipped with
First and second radio waves having the same frequency are transmitted from the first and second transceivers, and the first radio wave and the second radio wave are transmitted at the same radiation angle depending on the frequency. Each delay time until the signal is received by the other of the first and second transmitters / receivers by a propagation path reflected or blocked by an intruder or an obstacle is measured, and the distance between the pair of leaking cables and the radio wave velocity are measured. the emission angle, and the delay in the two-dimensional plane including the pair of leaky cable based on time, intruder and obstacle detection apparatus characterized by specifying the location of the intruder or obstacles. A pair of leaky cables laid in parallel;
A transmitter provided on one end side of the leakage cable;
The other of the leaky cables, a receiver provided on the same end side as one end of the one leaky cable;
A delay time measuring device for measuring a delay time until the radio wave transmitted from the transmitter is received by the receiver through the pair of leaky cables;
A switch for simultaneously switching connection between the transmitter and receiver and the pair of leaky cables;
The transmitter and receiver and the connection between the pair of leakage cable simultaneously switched by the switching unit, transmits the first radio and second radio wave of the same frequency from the transmitter to the pair of leaky cables and, up to the first radio and the second radio wave depending on the frequency being transmitted at the same angle of radiation is received at the receiver by reflection or blocked propagation path by an intruder or an obstacle the respective delay times are measured, the distance between the pair of leaky cable, radio wave speed, in the emission angle, and the two-dimensional plane including the pair of leaky cables on the basis of the delay time, the intruder or disorder An intruder and obstacle detection device characterized by specifying the position of an object. With two leaky cables laid in parallel, a transmitter that transmits radio waves is connected to the end of one leaky cable, and radio waves delayed according to position are received on the same cable end side of the other leaky cable In a device that connects a receiver and measures the delay time until the radio wave returns depending on the location of the intruder or obstacle,
Ri by the fact that switch the transmitter and the receiver to transmit a first radio wave before replacement, the second wave after replacement with the first radio and the same frequency, the same depending on the frequency Measuring each delay time until the first radio wave and the second radio wave transmitted at a radiation angle are received by the receiver through a propagation path reflected or blocked by an intruder or an obstacle , cable parallel to distance between leaky cable, radio wave speed, the emission angle, and in the two-dimensional plane including the laid leakage cable in parallel on the basis of the delay time, allow the localization of the intruder or an obstacle Intruder and obstacle detection device.

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