JPH06118172A - Acoustic position measuring device - Google Patents

Abstract

PURPOSE:To miniaturize an acoustic position-measuring device mounted at a buoy by installing one LBL receiver in the buoy for driving it with a small- capacity power supply. CONSTITUTION:This measuring device consists of a transmitter 6 for sending acoustic interrogation signals with different frequencies, a receiver 5 for receiving acoustic response signals, and a plurality of transponders 2 for sending the acoustic response signals with same frequencies to the acoustic interrogation signals with different frequencies. The acoustic interrogation signals with different frequencies are transmitted by time-sharing and a position is measured by obtaining a direct distance for each acoustic response signal to the acoustic interrogation signal. The acoustic interrogation signals with different frequencies are formed by a plurality of oscillators 10 with different oscillation frequencies and the acoustic interrogation signals are time-shared and transmitted by a selection switch 11 for switching the connection between the transmitter 6 and the receiver 5. Also, the receiver 6 and the transmitter 5 can be installed at a buoy 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positioning system for an acoustic positioning device.

[0002]

2. Description of the Related Art Conventional acoustic positioning will be described with reference to the configuration diagram of the conventional acoustic positioning apparatus shown in FIG. In FIG.
1 is water, 2-1 to 2-3 are first to third transponders installed on the seabed, 3 is a buoy installed in water, 4A is a wave transmitter installed in the buoy, and 4B is installed in the buoy. The received wave receivers 5-1 to 5-3 are first to third Long Base Lines (hereinafter, referred to as “L”) installed inside the buoy.
BL ”. ) A receiver, 6 is a transmitter, 7 is an arithmetic control unit, 8 is a display, and 9 is a reference clock.

The operation of the conventional acoustic positioning device having the above structure will be described below. The transmitter 6 receives a transmission command from the arithmetic and control unit 7 at regular intervals from a certain reference time according to the input from the reference clock 9, and transmits a transmission signal to the wave transmitter 4A. The wave transmitter 4A is driven by the transmission signal and transmits an ultrasonic pulse having a frequency f ₀ to the underwater 1.

When this ultrasonic pulse is received by the first to third transponders 2-1 to 2-3 as an acoustic interrogation signal, each transponder has a different frequency f ₁ ,
f ₂ , f ₃ (for example, f ₁ = 15 kHz, f ₂ = 16 k
The acoustic response signal of Hz, f ₃ = 17 kHz) is transmitted.
The acoustic response signals respectively transmitted from the first to third transponders 2-1 to 2-3 are received by the wave receiver 4A and converted into electric signals, and then the first to third LBs are received.
It is received by the L receivers 5-1 to 5-3.

In each of the LBL receivers 5-1 to 5-3, the transponder 2-1 is operated after the arithmetic control unit 7 outputs a transmission command.
~ Time until the acoustic response signal of 2-3 is detected (that is, the ultrasonic pulse is transmitted to the buoy 3 and the transponder 2-1 to 2-1.
2-1 to 2-3 from the propagation time to and from 2-3)
Measures the direct distance to the transponder (generally called the slant range).

FIG. 4 is a time chart of a conventional acoustic positioning device. In the figure, the acoustic interrogation signal of frequency f ₀ is transmitted from the wave transmitter 4A, and the first to third transponders 2 are transmitted.
In -1 to 2-3, the waves are received with a time difference. Each transponder transmits an acoustic response signal in response to the acoustic interrogation signal. The frequency of the acoustic response signal is different for each transponder. For example, the frequencies of the acoustic response signals of the first to third transponders 2-1 to 2-3 are f ₁ , f ₂ and f ₃ , respectively. The acoustic response signals of the first to third transponders 2-1 to 2-3 are received by the wave receiver 4 of the buoy 3.
The signal is received at B and received by the first to third LBL receivers.

Therefore, the time interval between the transmitter output and the receiver input of FIG. 4 is the round-trip propagation time between the buoy 3 and the transponder 2. That is, the first LBL receiver 5-1 receives the acoustic response signal of the frequency f ₁ transmitted from the first transponder 2-1 and measures its direct distance r ₁ . Further, the second LBL receiver 5-2 receives the acoustic response signal of the frequency f ₂ transmitted from the second transponder 2-2, and measures the direct distance r ₂ thereof. Similarly, the third L
BL receiver 5-3 receives the acoustic response signal of a frequency f ₃ which is transmitted from the third transponder 2-3, to measure the linear distance r _3. These measured direct distances r _{1 to} r ₃
Is supplied to the arithmetic control unit 7 from each LBL receiver 5-1 to 5-3.

First to third transponders 2-
When the position of 1～2-3 previously determined by an operator of the calibration, the position of the buoy 3 is calculated as the intersection of the straight distance r ₁ ~r ₃ from the first to third transponder 2-1 to 2-3 It The position coordinates of the buoy 3 calculated by the arithmetic control unit 7 can be displayed on the display 8.

In the apparatus having the above-mentioned configuration, when calculation is performed to find the intersections of the direct distances r _{1 to} r ₂ from the positions of the first to third transponders 2-1 to 2-3, the first to third transponders 2
The solution of the position of two buoys above and below the plane connecting -1 to 2-3 is obtained. As to which of these solutions to choose,
Select the solution above the sea floor. Although it is possible to display the positioning data on the display device 8, it is rare that a human enters the buoy to actually perform measurement. Therefore, in addition to the display unit 8, a data recording device is connected. Then, the data is stored in the data recording device and collected at a later date to collect the data.

By measuring the position of the buoy, the tidal current that determines the position of the buoy can be measured. Further, when another measuring device is attached to the buoy, it is also possible to measure the accurate position of the buoy and use it for adding position information to the measuring device.

[0011]

However, in the acoustic positioning device having the above configuration, the intersections of the direct distances r _{1 to} r ₃ are obtained from the positions of the first to third transponders 2-1 to 2-3. In an environment of special circumstances where three LBL receivers are required, the power supply capacity of a buoy is small, and the space for housing the device is also small, the three L
It is very difficult to secure a sufficient power source for driving the BL receiver, and it is structurally complicated to install the three LBL receivers.

In order to eliminate the drawbacks of the acoustic positioning device described above, it is an object of the present invention to reduce the size of the acoustic positioning device mounted on a buoy with one LBL receiver installed in the buoy.

[0013]

In order to achieve the above object, in an acoustic positioning device of the present invention, a transmitter for transmitting acoustic interrogation signals of different frequencies, and a receiver for receiving acoustic response signals, respectively. It consists of a plurality of transponders that transmit the acoustic response signals of the same frequency to the acoustic interrogation signals of different frequencies, and transmits the acoustic interrogation signals of different frequencies in a time division manner, and the acoustic response signal to the acoustic interrogation signals. Positioning is performed by obtaining the direct distance for each, the acoustic interrogation signal of different frequency is formed by a plurality of oscillators of different oscillation frequency, the time division transmission of acoustic interrogation signal, the transmitter and the oscillator. This is done by switching the connection of. Also, the transmitter and receiver can be installed on the buoy.

[0014]

In the acoustic positioning device of the present invention, the transponder is selected by changing the reception frequency of the transponder according to the above configuration, and the transmission frequencies of the plurality of transponders are set to the same reception frequency of the buoy. The above LBL receiver enables acoustic response signals from a plurality of transponders to be received, and the direct distance to each transponder is measured by time division.

Further, by installing the transmitter and the receiver on the buoy, the position of the buoy can be measured, and it can be applied to the measurement of the tidal current and the position information of the measuring device installed on the buoy.

[0016]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a configuration diagram of an acoustic positioning device of the present invention. In the figure, 1 is water, 2-1 to 2-3
Are first to third transponders respectively installed on the seabed, 3 is a buoy installed in water, 4A is a wave transmitter installed in the buoy, 4B is a wave receiver, and 5 is L installed inside the buoy.
on Base Line (hereinafter referred to as “LBL”) receiver, 6 transmitter, 7 arithmetic control unit, 8 display, 9 reference clock, 10-1 first oscillator, 10-2 second An oscillator, 10-3 is a third oscillator, and 11 is a changeover switch.

The operation of the acoustic positioning device of the present invention having the above configuration will be described below. First, the reference clock 9 inside the buoy 3
According to the time data input from, the transmitter 6 repeats transmission from a certain reference time at regular intervals. In this transmission, the transmitter 6 receives the transmission command signals of different frequencies from the first oscillator 10-1 to the third oscillator 10-3. The changeover switch 11 switches the transmission command signals of the first oscillator 10-1 to the third oscillator 10-3 to the transmitter 6. The changeover switch 1
Switching of 1 is controlled by a signal from the arithmetic control unit 7.

Therefore, signals of different frequencies are sequentially and periodically output from the transmitter 6, and the output of the transmitter is the transmitter 4A.
Ultrasonic pulses are transmitted into the water via. These frequencies are different frequencies f ₁ , f ₂ , f ₃ (for example, f
_{1 = 10kHz, f 2 = 11.0kHz} , f 3 = 11.
5 kHz). The ultrasonic pulse transmitted from the wave transmitter 4A becomes an acoustic interrogation signal, and the first to third transponders 2-1 to 2-3 installed on the seabed.
Sent to. First to third transponders 2-1 to 2-
The frequency of the acoustic response signal in 3 is the same frequency f
₄ (for example, f ₄ = 15 kHz).

First, when the first oscillator 10-1 is selected by the changeover switch 11, the transmitter 6 transmits an acoustic interrogation signal of frequency f ₁ . When the acoustic interrogation signal of the frequency f ₁ is received by the first transponder 2-1, the transponder 2-1 transmits the acoustic response signal having the same frequency as the other transponders 2-2 and 2-3. Second, third
The transponders 2-2 and 2-3 have frequencies f ₂ ,
Since it is set to respond to the acoustic interrogation signal of f ₃ , it does not respond to the acoustic interrogation signal of frequency f ₁ and does not transmit the acoustic response signal.

Therefore, the only transponder which responds to the acoustic interrogation signal of frequency f ₁ is the first transponder, and what is received by the receiver 4B is the acoustic response of frequency f ₄ transmitted from the first transponder. Become a signal. Next, when the transmission frequency is sequentially switched by transmitting the oscillator connected to the transmitter 6 by the changeover switch 11, the first to third transponders 2-1 are transmitted.
The acoustic response signals respectively transmitted from ~ 2-3 are received by the wave receiver 4A and converted into electric signals, and then LB.
It is received by the L receiver 5.

FIG. 2 is a time chart of the acoustic positioning device of the present invention. The output from the transmitter 4A is the changeover switch 1
According to the frequencies f ₁ , f ₂ and f _{3 of the first} to third oscillators connected to the transmitter 6 according to the switching timing of ₁ ,
Acoustic inquiry signals of frequencies f ₁ , f ₂ , and f ₃ are transmitted in order. The output interval of the transmitter output is determined by the switching interval of the changeover switch 11.

When the first transponder 2-1 receives the acoustic interrogation signal having the frequency f ₁ from the first oscillator, it receives the frequency f _1.
The acoustic response signal ₄ is transmitted, and the wave receiver 4B of the buoy 3 receives the acoustic response signal. The time interval between the transmitter output and the receiver input corresponds to twice the direct distance r ₁ between the buoy 3 and the first transponder 2-1. Next, by switching the changeover switch 11, the frequency f _{2 of} the second oscillator is changed.
Of the acoustic interrogation signal of, and the wave receiver 4B receives the acoustic response signal of the frequency f ₄ according to the acoustic interrogation signal. The time interval between the transmitter output and the receiver input is the buoy 3 and the second
This corresponds to twice the direct distance r ₂ with the transponder 2-2.

Further, the changeover switch 11 is switched to transmit the acoustic interrogation signal of the frequency f ₃ of the third oscillator, and the receiver 4B receives the acoustic response signal of the frequency f ₄ according to the acoustic interrogation signal. The time interval between the transmitter output and the receiver input corresponds to twice the direct distance r ₃ between the buoy 3 and the third transponder 2-3. The switching timing of the change-over switch 11 is set so as to be connected to the oscillator of the next frequency after receiving the acoustic response signal to the acoustic interrogation signal transmitted by the oscillator of a certain frequency. The above setting is such that if the next acoustic inquiry signal is transmitted before the acoustic response signal for the previous acoustic inquiry signal is received, depending on the installation position of the transponder, the next acoustic response signal may be received before the previous acoustic response signal is received. This is because a response signal may be received, and it may be impossible to distinguish the transponder that responded.

The LBL receiver 5 measures the direct distance to the transponder 2 from the time from when the arithmetic control unit 7 outputs the transmission command until the acoustic response signal of the transponder 2 is detected. That is, the LBL receiver 5 transmits the frequency f ₁ from the buoy 3, receives the acoustic response signal of the frequency f ₄ transmitted from the first transponder 2-1, and measures the direct distance r ₁ .

The LBL receiver 5 has a frequency higher than that of the buoy 3.
f₂Is transmitted from the second transponder 2-2.
Frequency f_FourOf the acoustic response signal of the
₂To measure. Similarly, the LBL receiver 5 is
₃Is transmitted from the third transponder 2-3.
Frequency f_FourOf the acoustic response signal of the ₃
To measure.

The data of the measured direct distances r _{1 to} r ₃ are L, together with information indicating which frequency is transmitted.
It is supplied from the BL receiver 5 to the arithmetic control unit 7. Based on this transmission frequency information, each transponder and the direct distance r
Correspondence with the data of _{1 to} r ₃ can be performed. If the positions of the first to third transponders 2-1 to 2-3 are determined in advance by a work called calibration, the position of the buoy 3 will be set to the first to third transponders 2-1.
Is calculated as an intersection of straight distances r ₁ to r ₃ from ˜2-3.

In the apparatus having the above-described structure, when calculation is performed to find the intersections of the direct distances r _{1 to} r ₃ from the positions of the first to third transponders 2-1 to 2-3, the first to third transponders 2
The solution of the position of two buoys above and below the plane connecting -1 to 2-3 is obtained. The solution existing on the seabed is selected from these two solutions and the positioning data is displayed on the display 8. Actually, it is rare for a person to enter the buoy 3 to perform measurement. Therefore, as a normal use method, a data recording device is connected to the arithmetic control unit 7 and the measurement data is recorded in the data recording device. It will be collected at a later date and the data will be measured.

The position information of the buoy measured as described above can be used as data for measuring the tidal current. Further, when another measuring device is attached to the buoy, accurate position information can be added to the measurement data of the measuring device for use. The present invention is not limited to the above-described embodiments, and various modifications can be made based on the spirit of the present invention, and these modifications are not excluded from the scope of the present invention.

[0029]

As described above in detail, the present invention has the following effects. (1) Since it is possible to measure the direct distance from the three transponders with one LBL receiver, a small and lightweight positioning device can be provided. (2) Further, since positioning can be performed by one LBL receiver, it can be driven by a small capacity power source.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an acoustic positioning device of the present invention.

FIG. 2 is a time chart of the acoustic positioning device of the present invention.

FIG. 3 is a configuration diagram of a conventional acoustic positioning device.

FIG. 4 is a time chart of a conventional acoustic positioning device.

[Explanation of symbols]

 1 Underwater 2-1 to 2-3 Transponder 3 Buoy 4A Wave transmitter 4B Wave receiver 5 LBL receiver 6 Transmitter 7 Arithmetic control unit 8 Display 9 Reference clock 10-1 to 10-3 Oscillator 11 Changeover switch

Front Page Continuation (72) Inventor ▲ Takahashi Hideyuki Hashi 1-1-12 Toranomon, Minato-ku, Tokyo Oki Electric Industry Co., Ltd.

Claims (4)

[Claims] 1. A transmitter for transmitting acoustic interrogation signals of different frequencies, a receiver for receiving acoustic response signals of (b), and (c) acoustic interrogation signals of different frequencies,
A plurality of transponders that transmit the acoustic response signal of the same frequency, and (d) transmit the acoustic interrogation signals of different frequencies in a time division manner, and obtain the direct distance for each acoustic response signal to the acoustic interrogation signal. An acoustic positioning device characterized in that positioning is performed by using. 2. The acoustic positioning device according to claim 1, wherein the acoustic interrogation signals having different frequencies are formed by a plurality of oscillators having different oscillation frequencies. 3. The acoustic positioning device according to claim 2, wherein the time division transmission of the acoustic interrogation signal is performed by switching a connection between the transmitter and the oscillator. 4. The acoustic positioning device according to claim 1, wherein the transmitter and the receiver are installed in a buoy.