JPH08136650A - Acoustic position measuring instrument - Google Patents

Abstract

PURPOSE: To accurately monitor the movement of a submarine from a submarine tender even when the submarine has excellent maneuverability by providing a GPS receiver which is mounted on the tender and outputs the position measuring information of the tender. CONSTITUTION: An arithmetic and control section 7 calculates the direct distances r1 -r3 from a submarine tender 12 to transponders 2-1 to 2-3 based on the position measuring information of the tender 12 measured by means of a GPS receiver 13 and average GPS error information received by means of radio equipment 14. Therefore, no underground acoustic wave is used at the time of measuring the position of the tender 12, but used only when the direct distances r21 -r23 from a submarine 3 to the transponders 2-1 to 2-3 are measured. In other words, ultrasonic pulses transmitted from the pinger 4 of the submarine 3 synchronously to a reference clock 9 are received by means of the transponders 2-1 to 2-3 as interrogating signals. The response signals to the interrogating signals are received by means of a receiver 11 and converted into electric signals. LBL receivers 5-1 to 5-3 receive the electric signals and the arithmetic and control section 7 calculates the position of the submarine 3.

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art Known examples of an acoustic positioning device for measuring the position of a ship or a moving object in water using underwater acoustic waves include, for example, "Marine Acoustics (Reference and Application) P209-".
214, 1984, Ocean Acoustics Research Society ".

FIG. 3 is a functional block diagram of a conventional acoustic positioning device shown in the above document. In FIG. 3, 1 is underwater, and 2-1 to 2-3 are installed on the seabed at the apex of the triangle including the moving area of the submersible or the underwater vehicle, respectively.
1 to # 3 transponder, 3 is an underwater submersible or a vehicle, 4 is a pinga attached to the submarine 3, 5-1 to 5-3
Is # 1 to # 3 Long Ba installed on the mother ship on the water
se Line (hereinafter referred to as LBL) receiver, 6 is a transmitter, 7 is a calculation control unit, 8 is a display, 9 is a reference clock, 10
Is a wave transmitter, 11 is a wave receiver, and 12 is a mother ship.

The transmitter 10 and the receiver 11 are mounted on the bottom of the mother ship 12 so as to transmit and receive underwater acoustic waves.
Other devices are provided inside the mother ship 12. Then, between the wave transmitter 10 and the transmitter 6 and between the wave receiver 11 and # 1 to # 3.
The LBL receivers 5-1 to 5-3 are connected by waterproof cables. The # 1 to # 3 transponders 2-1 to 2-3 are installed such that their mutual intervals are separated from each other by a distance (for example, about 2 km) which is generally equal to the water depth. The distance between these transponders is called the baseline length, and the long length is the LBL (Long Base).
This is the reason why it is called the Line method.

FIG. 4 is a waveform diagram for explaining the acoustic positioning operation of FIG. 3, and referring to FIG. 4, the configuration of FIG.
The operation of the acoustic positioning device will be described. First, the arithmetic control unit 7 in the mother ship 12 supplies a transmission command repeatedly to the transmitter 6 at regular intervals T from a certain reference time based on the time data input from the reference clock 9 (see (a) of FIG. 4). ). In response to this transmission command, the transmitter 6 immediately excites the wave transmitter 10 to transmit an ultrasonic pulse (generally a burst wave) into the water 1.
When the ultrasonic pulse is received to the # 1 to # 3 transponders 2-1 to 2-3 as an interrogation signal, each transponder, the frequency f _1, f _2, f ₃ a different immediate respectively
(For example, f ₁ = 15 kHz, f ₂ = 16 kHz, f ₃ =
(17 kHz). # 1 to #
The acoustic response signals respectively transmitted from the three transponders 2-1 to 2-3 are received by the wave receiver 11 and converted into electric signals, and then the # 1 to # 3 LBL receivers 5-1 to -5.
-3 is received individually for each frequency f ₁ , f ₂ , f ₃ .

Now, the wave receiver 11 to each transponder 2-
Assuming that the direct distances (generally called slant ranges) from 1 to 2-3 are r ₁₁ , r ₁₂ , and r ₁₃ and the propagation velocity of the underwater acoustic wave is C (about 1500 m / sec), each LBL receiver 5- 1 to 5-3 is the time from when the arithmetic control unit 7 outputs the transmission command to when the response signal of the transponder is detected exceeding the threshold value, that is, the ultrasonic pulse is the direct distance r.
_11, the r _12, the propagation time t ₁₁ to reciprocate r _13, t _12, t ₁₃ measures, calculates each linear distance. That is, # 1 LBL receiver 5
-1 receives the response signal of a frequency f ₁ transmitted from the # 1 transponder 2-1, from the propagation time t _11, calculates the straight distance r ₁₁ = Ct _11/2. The # 2LBL receiver 5-2 receives a response signal of a frequency f ₂ transmitted from # 2 transponders 2-2, from the propagation time t _12, calculates the straight distance r ₁₂ = Ct _12/2. Likewise # 3LBL receiver 5-3 receives a response signal of frequency f ₃ transmitted from the # 3 transponders 2-3, from the propagation time t _13, calculates the straight distance r ₁₃ = Ct _13/2 ((B) of FIG. 4
See).

Direct distance r calculated by each LBL receiver
The data of ₁₁ , r ₁₂ , and r ₁₃ are supplied to the arithmetic control unit 7, respectively. # 1 to # 3 transponder 2-1 in advance
By determining the positions of 2-3 through a calibration operation, the arithmetic control unit 7 causes the mother ship 12
Can be calculated as the intersection point positions of the direct distances r ₁₁ , r ₁₂ , and r ₁₃ from the # 1 to # 3 transponders 2-1 to 2-3.

The submarine 3 is equipped with a pinger 4 generally called "synchronous pinga" which operates in synchronization with the reference clock 9 in the mother ship 12, and the time when the transmitter 10 of the mother ship 12 transmits a sound wave. After a fixed delay time τ has passed, the pinger 4 transmits an ultrasonic pulse (see (c) of FIG. 4).
In addition, the arithmetic control unit 7 in the mother ship 12 uses the constant delay time τ
Since it knows the value of, the transmission time of the pinger 4 is known. The ultrasonic pulses transmitted from the pinga 4 of the submersible 3 are used as interrogation signals # 1 to # 3 transponder 2
Received by -1～2-3, each transponder, as in the case of the interrogation signal from the mother ship 12, and transmits an acoustic response signal by the frequency f _1, f _2, f ₃ a different immediately, respectively. These acoustic response signals are received by the wave receiver 11 of the mother ship 12, converted into electric signals, and then received by the # 1 to # 3 LBL receivers 5-1 to 5-3, respectively.

Now from the pinger 4 to each transponder 2-1
Each of the LBL receivers 5-1 to 5-1 is assumed to have a direct distance of up to 2-3 as r ₂₁ , r ₂₂ and r ₂₃ and a propagation velocity of an underwater acoustic wave as C.
5-3 measures time t ₂₁ , t ₂₂ , t ₂₃ from when the pinga 4 of the submersible 3 transmits a sound wave until the response signal relayed by each transponder exceeds the threshold and is detected. The respective direct distances (r ₂₁ + r ₁₁ ) corresponding to the time, (r ₂₂
+ R ₁₂ ) and (r ₂₃ + r ₁₃ ) are calculated (see (d) in FIG. 4).

That is, the # 1 LBL receiver 5-1 receives the response signal of the frequency f ₁ transmitted from the # 1 transponder 2-1, and the direct distance (r ₂₁ + r ₁₁ ) = from the measurement time t ₂₁ thereof.
Calculate Ct ₂₁ . Also, the # 2 LBL receiver 5-2 is the # 2
Receiving a response signal of frequency f ₂ transmitted from the transponder 2-2, straight distance from the measured time t ₂₂ (r ₂₂ + r
₁₂ ) = Ct ₂₂ is calculated. Similarly, # 3LBL receiver 5-
3 is the frequency f transmitted from the # 3 transponder 2-3
The response signal ₃ is received, and the direct distance (r ₂₃ + r ₁₃ ) = Ct ₂₃ is calculated from the measured time t ₂₃ . Then, the data of the direct distances are supplied to the arithmetic control unit 7.

The arithmetic and control unit 7 operates from the submersible 3 supplied from each LBL receiver to the mother ship 1 via each transponder.
3 direct distances up to 2 (r ₂₁ + r ₁₁ ), (r ₂₂ +
r ₁₂ ), (r ₂₃ + r ₁₃ ) data, the direct distances r ₁₁ , r ₁₂ , r ₁₃ between the transponders and the mother ship 12 obtained at the time of measuring the position of the mother ship 12 are subtracted, and each transponder and the submersible 4 The direct distances r ₂₁ , r ₂₂ , and r _{23 up} to are obtained. Next, the arithmetic control unit 7 uses the calibrated # 1 to # 1.
The position of the submersible 3 can be calculated as the intersection position of the three direct distances r ₂₁ , r ₂₂ , and r ₂₃ from the positions of the # 3 transponders 2-1 to 2-3. The calculated position of the submersible 3 is displayed on the display 8. Such a method of alternately measuring the positions of the mother ship and the underwater submersible using the underwater acoustic wave is generally called a SHIP / SUB mode measurement method.

[0012]

However, in the acoustic positioning device having the above configuration, the frequency of the inquiry signal from the mother ship and the transmission frequency of the pinga of the submarine to the three transponders are the same, so that the SHIP / SUB is the same. As in the mode measurement method, it is necessary to measure the mother ship and submersible alternately in time. Since the propagation speed of acoustic waves in water is as low as about 1500 m / sec, it takes a long time of several seconds to 10 seconds to measure the mother ship and the submersible when the transponder is installed at a deep water depth of, for example, about 2 km.
For this reason, there is a problem that the measurement interval becomes large and the movement of the submersible cannot be accurately monitored from the mother ship when the submersible has good movement performance.

[0013]

An acoustic positioning device according to the present invention has at least three transponders installed on the seabed around a moving region of an underwater moving object, and each position of the transponders is calibrated in advance. In an acoustic positioning device that is fixed and measures the position of an underwater moving object from a waterborne mother ship within the movement area, GPS reception that receives radio waves from GPS satellites mounted on the mother ship and sequentially outputs positioning information of the mother ship Machine, a synchronizing pinger mounted on the underwater moving object, which transmits an acoustic wave pulse repeatedly at regular intervals from a reference time synchronized with the reference clock in the mother ship, and mounted on the mother ship and transmitted from the synchronizing pinger. Receiving each acoustic wave transmitted as a response signal from each transponder based on the acoustic wave pulse, and from the time required for its propagation, By at least three underwater acoustic wave receiving means for measuring each direct distance from the underwater moving object to the mother ship via each transponder, and by at least three underwater acoustic wave receiving means mounted on the mother ship. From each measured direct distance from the underwater moving object to the mother ship via each transponder, the position of each transponder determined by the calibration and the GPS
Subtract each direct distance between each transponder and the mother ship obtained from the positioning information of the mother ship output by the receiver, and calculate each direct distance from each underwater moving object to each transponder,
And a position calculating means for calculating the position of the underwater moving object from the calculated direct distances.

[0014]

In the present invention, at least three transponders are installed on the seabed around the moving area of the underwater moving object, and the respective positions of the transponders are determined by calibration in advance, and In an acoustic positioning device that measures the position of an underwater moving object from a waterborne mother ship, a GPS receiver is mounted on the mother ship and receives radio waves from GPS satellites, and sequentially outputs positioning information of the mother ship. Is mounted on the mother ship and repeatedly transmits acoustic wave pulses at regular intervals from a reference time synchronized with the reference clock inside the mother ship, and at least three underwater acoustic wave receiving means are mounted on the mother ship and transmitted from the synchronization pinga. Receiving each of the acoustic waves transmitted as a response signal from each of the transponders based on the acoustic wave pulse, the propagation required time, Each straight distance from serial underwater moving objects to the mother ship, which via each transponder is measured,
The position calculating means is mounted on the mother ship, and is determined by the calibration from each direct distance from the underwater moving object measured by the at least three underwater acoustic wave receiving means to the mother ship via each transponder. The respective direct distances of the transponders and the mother ship obtained from the position of each transponder and the positioning information of the mother ship output by the GPS receiver are respectively subtracted to calculate the respective direct distances of the transponders from the underwater moving object, Since the position of the underwater moving object is calculated from each of the calculated direct distances, the measurement using the underwater acoustic wave is performed only when the direct distance between the underwater moving object and each transponder is obtained, and the measurement interval is the same as the conventional one. As a result of being shortened to less than half of the SHIP / SUB mode measurement method, even if the moving performance of the underwater moving object is good, the underwater moving object from the mother ship Consisting of motion can be accurately monitored.

[0015]

FIG. 1 is a functional block diagram of an acoustic positioning device according to the present invention. In FIG. 1, reference numeral 13 denotes a GPS receiver (including an antenna) mounted on the mother ship 12, which supplies GPS positioning signals to the sequential calculation control unit 7. Reference numeral 14 denotes a wireless device (including an antenna), which receives GPS average error information transmitted from a reference position on land and supplies this received information to the arithmetic control unit 7. 1-5-3, 7-9, 11 in FIG.
And 12 are the same as in FIG. Therefore, the apparatus having the configuration shown in FIG. 1 is obtained by removing the transmitter 6 and the transmitter 10 from the apparatus having the configuration shown in FIG. 3 and providing a GPS receiver 13 and a radio 14 on the mother ship 12 instead. Although the arithmetic control unit 7 has the same configuration, the operation content is different between FIG. 1 and FIG.

The function of the acoustic positioning device of FIG. 1 is essentially different from that of the device of FIG. 3 in that the positions of the transponders # 1 to # 3 are fixed by calibration in advance, and then the position of the mother ship 12 is received by GPS. It is a point measured by the machine 13. That is, the mother ship 12 measured by the GPS receiver 13
The calculation control unit 7 calculates the direct distances r ₁₁ , r ₁₂ , and r ₁₃ between the mother ship 12 and each transponder based on the positioning information of No. 1 and the GPS average error information received by the wireless device 14. Therefore, the underwater acoustic wave is not used for the position measurement of the mother ship 12, and only when the direct distances r ₂₁ , r ₂₂ and r ₂₃ between the submersible 4 and each transponder are measured, the underwater acoustic wave is obtained as in the case of FIG. Measure using waves. 2 is a waveform diagram for explaining the acoustic positioning operation of FIG. 1, and the operation of FIG. 1 will be described below with reference to FIG.

First Step First, when the moving area of the underwater moving object in water is determined,
Usually, a circle including this moving area is drawn, and three points on this circumference (for example, 3 which are the vertices of a triangle inscribed in this circle)
Points), and # 1 to # 3 transponders 2-1 to 2-3 are installed on these three seabeds, respectively. Next, three-dimensional coordinates used to measure the position of the submersible 3 are set. This 3
The values x, y, z on each axis of the dimensional coordinate generally correspond to the longitude, latitude and altitude (or depth) indicating the position on the earth, and the coordinate position between the two can be converted. I wish I had it. Next, according to the three-dimensional coordinates installed above, each position P ₁ (x ₁ ,
y ₁ , z ₁ ), P ₂ (x ₂ , y ₂ , z ₂ ), P
₃ (x ₃ , y ₃ , z ₃ ) is fixed by a work called calibration.

Second step The position P ₀ (x ₀ , y ₀ , of the mother ship 12 is determined from the GPS positioning information.
z ₀ ), GPS (Global Posi) mounted on the mother ship 12
The positioning system receiver 13 selects, through its own antenna, three satellites in good reception condition out of the 24 artificial satellites traveling in outer space about 21,000 km above the surface of the earth, and the GPS radio waves of these satellites are selected. GPS that is calculated by receiving positioning information and calculating positioning information (longitude, latitude and altitude information) of the mother ship 12 at a rate of about once per second.
Positioning information is sequentially supplied to the arithmetic control unit 7. However, the positioning information obtained by a general civilian GPS receiver is about 1
In addition to the measurement error of about 100 to 200 meters, the measured value constantly fluctuates due to the operating position of GPS satellites and the propagation state of GPS radio waves (for example, the propagation state of radio waves changes if a sunspot occurs on the sun). , There are variations. Therefore, in the present invention, a plurality of positioning information is used to average the dispersion of the measured values, and G obtained from the GPS receiver for error evaluation provided at the reference position on land is used.
When the PS average error information is available, the GPS average error information is used to correct the average value of the GPS positioning information to improve the accuracy of the measurement position of the mother ship 12.

The arithmetic and control unit 7 has a built-in memory capable of storing a predetermined number of positioning information. The positioning information sequentially input from the GPS receiver 13 is sequentially stored in the memory, and the memory becomes full. Then, the newest positioning information is written to the address where the oldest positioning information is stored in the memory to update the information. In this way, a predetermined number of updated positioning information is constantly stored. Meanwhile submersible 3
Since the mother ship 12 usually stops the engine during the work of (1) and is drifting over the sea, it can be considered that the mother ship 12 is in substantially the same position within a short time. Therefore, the arithmetic control unit 7 reads out a plurality of positioning information within the time when the mother ship 12 can be considered to be at the same position from its built-in memory, and calculates the average value (substantially the moving average value). By this averaging process, the dispersion of the GPS measurement values converges, but the average error (error included in the average value like the offset value) is not removed, so the GPS positioning error is still large.

In order to eliminate the GPS positioning average error of the mother ship 12, a land reference position relatively close to the mother ship 12 (this reference position is about 21,000 k used for GPS measurement).
It is desirable that the azimuths and distances of the mother ship 12 and this reference position from each satellite above m can be considered to be approximately equal, and the information on the longitude, latitude, and altitude of this reference position is Pre-calibrated and known. ), A GPS receiver for error evaluation is installed. Next, using this GPS receiver for error evaluation, a moving average value (longitude, latitude, and altitude average value) of a plurality of positioning information that is sequentially measured from GPS satellites is calculated. By comparing each of the calibration values of longitude, latitude and altitude of a certain reference position, the average error of the GPS positioning information (longitude,
Calculate each average error of latitude and altitude).

The average error of the GPS positioning information calculated at the reference position on land in this manner is transmitted to the mother ship 12 via a radio device or the like. On the mother ship 12, this transmitted GPS
The wireless device 14 receives the average error information, and supplies the received information to the arithmetic control unit 7. The arithmetic control unit 7 receives GPS average error information (each average error of longitude, latitude and altitude) received from the radio 14 with respect to the calculated average value of the positioning information (longitude, latitude and altitude) of the mother ship 12. Is corrected, and the corrected position P ₀ (x ₀ , y ₀ , z ₀ ) of the mother ship 12 is corrected.
To calculate. By correcting the GPS positioning average error in this manner, an error of about 100 to 200 meters originally held by the positioning information from the GPS receiver 13 is reduced to 10 to 2
The error can be reduced to about 0 meters. The altitude of the mother ship 12 (the altitude of the GPS antenna) is regarded as the sea level, and the correction of the altitude can be omitted.

Third step Calculation of direct distances r ₁₁ , r ₁₂ and r ₁₃ between the mother ship 12 and the # 1 to # 3 transponders 2-1 to 2-3, and the arithmetic control unit 7 measures the positioning of the GPS receiver 13. Position P ₀ (x ₀ , y ₀ , z ₀ ) of the mother ship 12 obtained based on the information
And the positions P ₁ (x ₁ , y ₁ , z ₁ ) and P ₂ (x ₂ ,
y ₂ , z ₂ ), P ₃ (x ₃ , y ₃ , z ₃ ) and the direct distances r ₁₁ , r ₁₂ , r ₁₃ between them are calculated by the following formula (1),
It is calculated by (2) and (3).

[0023]

[Equation 1]

Fourth step Calculation of the direct distances r ₂₁ , r ₂₂ , r ₂₃ between the submersible 3 and the # 1 to # 3 transponders 2-1 to 2-3. This step is the step in the SUB mode described in FIG. Although it is almost the same as the above, the main part will be described repeatedly. The submarine 3 is equipped with a pinga 4 which is generally called "synchronous pinga" and which operates in synchronization with the reference clock 9 in the mother ship 12,
The pinker 4 repeatedly transmits an ultrasonic pulse at regular intervals T from a certain reference time (see (a) of FIG. 2). The arithmetic and control unit 7 is aware of each transmission time of the pinger 4 that operates in synchronization with the reference clock 9 in the mother ship 12.

The ultrasonic pulses transmitted from the pinga 4 of the submersible 3 are used as interrogation signals # 1 to # 3 transponder 2-.
1 to 2-3, each transponder immediately receives a different frequency f ₁ , f ₂ , f ₃ (eg f.
_{1 = 15kHz, f 2 = 16kHz} , f 3 = 17kH
The acoustic response signal according to z) is transmitted. Then, these acoustic response signals are received by the receiver 11 of the mother ship 12,
# 1 to # 3 LBL receiver 5-after being converted into an electric signal
1 to 5-3.

Now, from the pinger 4 to each transponder 2-1.
Each of the LBL receivers 5-1 to 5-1 is assumed to have a direct distance of up to 2-3 as r ₂₁ , r ₂₂ and r ₂₃ and a propagation velocity of an underwater acoustic wave as C.
5-3 measures the times t ₁ , t ₂ and t ₃ from when the pinger 4 of the submersible 3 transmits a sound wave until the response signal relayed by each transponder exceeds the threshold and is detected. The respective direct distances (r ₂₁ + r ₁₁ ) corresponding to the time, (r ₂₂
+ R ₁₂ ) and (r ₂₃ + r ₁₃ ) are calculated (see (b) in FIG. 2).

That is, the # 1 LBL receiver 5-1 receives the response signal of the frequency f ₁ transmitted from the # 1 transponder 2-1, and the direct distance (r ₂₁ + r ₁₁ ) = from the measurement time t ₁ thereof.
Calculate Ct ₁ . Also, the # 2 LBL receiver 5-2 is the # 2
Receiving a response signal of frequency f ₂ transmitted from the transponder 2-2, the measured time t ₂ from the straight distance (r ₂₂ + r
₁₂ ) = Ct ₂ is calculated. Similarly, # 3LBL receiver 5-
3 is the frequency f transmitted from the # 3 transponder 2-3
The response signal ₃ is received, and the direct distance (r ₂₃ + r ₁₃ ) = Ct ₃ is calculated from the measured time t ₃ . Then, the data of the direct distances are supplied to the arithmetic control unit 7.

The arithmetic and control unit 7 operates from the submarine 3 supplied from each LBL receiver to the mother ship 1 via each transponder.
3 direct distances up to 2 (r ₂₁ + r ₁₁ ), (r ₂₂ +
From the data of r ₁₂ ), (r ₂₃ + r ₁₃ ), the above formula (1),
Each transponder and mother ship 1 determined by (2) and (3)
The direct distances r ₁₁ , r ₁₂ , r ₁₃ to 2 are subtracted to obtain the direct distances r ₂₁ , r ₂₂ , r ₂₃ to each transponder and the submarine 4.

Fifth step: Calculation of the position of the submarine 3, and then the arithmetic control unit 7 makes the calibrated #
Positions P ₁ and P of ₁ to # 3 transponders 2-1 to 2-3
It is possible to calculate the position of the submersible 3 as an intersection position of three straight distances r ₂₁ , r ₂₂ , r ₂₃ from ₂ , P ₃ . The calculated position of the submersible 3 is displayed on the display 8. In addition, when calculating the position of the submarine 3, theoretically, #
Two positions, an upper side and a lower side of a plane including 1 to # 3 transponders 2-1 to 2-3 (substantially the same as the seabed) are required, but since the submersible 3 does not exist below the seabed,
The position above the seabed is naturally selected.

Since the measurement using the underwater acoustic wave is performed only when the direct distance between the submersible and each transponder is obtained, the measurement interval is shortened to less than half of the conventional one.
Even when the performance of the submersible is good, the movement of the submersible can be accurately monitored from the mother ship. In addition, since the GPS receiver is used to measure the position of the mother ship and the average error of the GPS positioning information is corrected, the position of the mother ship can be measured with high accuracy. As a result, the position of the mother ship was used. The accuracy of the position measurement of the submersible can also be improved.

[0031]

As described above, according to the present invention, at least three transponders are installed on the seabed around the moving region of an underwater moving object, and the respective positions of the transponders are previously determined by calibration. Every other time, in the acoustic positioning device for measuring the position of the underwater moving object from the waterborne mother ship in the movement area, the GPS receiver receives radio waves from GPS satellites mounted on the mother ship and sequentially outputs positioning information of the mother ship, The synchronizing pinger is mounted on the underwater moving object, and repeatedly transmits acoustic wave pulses at regular intervals from a reference time synchronized with the reference clock in the mother ship, and at least three underwater acoustic wave receiving means are mounted on the mother ship. And receiving each acoustic wave transmitted as a response signal from each of the transponders based on the acoustic wave pulse transmitted from the synchronization pinger, and From the time required for sowing, each direct distance from the underwater moving object to the mother ship via each transponder is measured, and the position calculating means is mounted on the mother ship and measured by the at least three underwater acoustic wave receiving means. From each direct distance from the underwater moving object to the mother ship via each transponder, each transponder and mother ship obtained from the position of each transponder determined by the calibration and the positioning information of the mother ship output by the GPS receiver. By subtracting each of the direct distances from and, to calculate each direct distance from the underwater moving object to each transponder, so as to calculate the position of the underwater moving object from each calculated direct distance, the underwater acoustic wave The measurement interval used is the conventional S
It is shortened to less than half of the HIP / SUB mode measurement method, and the motion of the underwater moving object can be accurately monitored from the mother ship even when the moving performance of the underwater moving object is good.

[Brief description of drawings]

FIG. 1 is a functional block diagram of an acoustic positioning device according to the present invention.

FIG. 2 is a waveform diagram illustrating the acoustic positioning operation of FIG.

FIG. 3 is a functional block diagram of a conventional acoustic positioning device.

FIG. 4 is a waveform diagram illustrating the acoustic positioning operation of FIG.

[Explanation of symbols]

 1 Underwater 2-1 to 2-3 Transponder 3 Submersible 4 Pingers 5-1 to 5-3 LBL receiver 7 Arithmetic control unit 8 Display 9 Reference clock 11 Wave receiver 12 Mother ship 13 GPS receiver 14 Radio equipment

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor ▲ Takahashi Hideyuki Toranomon 1-7-12 Toranomon, Minato-ku, Tokyo Oki Electric Industry Co., Ltd.

Claims (3)

[Claims] 1. At least three transponders are installed on the seabed around the moving area of an underwater moving object, and the respective positions of the transponders are preliminarily determined by calibration. In an acoustic positioning device for measuring the position of an underwater moving object, a GPS receiver mounted on the mother ship for receiving radio waves from GPS satellites and successively outputting positioning information of the mother ship; A synchronization pinger that repeatedly transmits an acoustic wave pulse at regular intervals from a reference time synchronized with a reference clock in the ship, and is mounted on the mother ship, and as a response signal from each transponder based on the acoustic wave pulse transmitted from the synchronization pinga. Each transmitted acoustic wave is received, and from the time required for its propagation, the underwater moving object passes through each transponder. The at least three underwater acoustic wave receiving means for measuring the respective direct distances to the mother ship, and the underwater moving object mounted on the mother ship and measured by the at least three underwater acoustic wave receiving means. From each direct distance to the mother ship via the transponder, each direct distance between each transponder and the mother ship obtained from the position of each transponder determined by the calibration and the positioning information of the mother ship output by the GPS receiver, respectively. An acoustic positioning device, comprising: a position calculating means that subtracts and calculates each direct distance from an underwater moving object to each transponder, and calculates the position of the underwater moving object from each calculated direct distance. 2. The position calculating means calculates an average value of a plurality of positioning information sequentially output from the GPS receiver of the mother ship within a time period in which the mother ship can be considered to be at substantially the same position. The acoustic positioning device according to claim 1, comprising: 3. The position calculating means is supplied with GPS positioning average error information calculated based on the positioning information of an error-evaluating GPS receiver installed at a reference position on land, and is calculated by the average value calculating means. The acoustic positioning device according to claim 2, further comprising: an average value correction unit that corrects the average value of the GPS positioning information of the mother ship, which is supplied, by the supplied GPS positioning average error information.