JP2716154B2 - Active sonar device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an active sonar device that emits a sound wave and receives a reflected sound from a target, and in particular, simultaneously searches for a short distance target and a long distance target. It relates to an active sonar device that can be used.

2. Description of the Related Art Conventionally, this kind of active sonar device is composed of one transmitter for transmitting one frequency and one receiver corresponding to this transmission frequency. Search in chronological order.

For example, as shown in FIG. 5, a search for a short distance target is performed several times, a search for a long distance target is performed, and then a search for a short distance target is performed again. I was doing it.

[Problem to be Solved] In the conventional active sonar device described above, the search for the short-range target and the search for the long-range target are performed in chronological order. It was impossible to search for a target at a short distance, and during a time period in which a search for a long-distance target was being performed, it was impossible to search for a target at a short distance. This has the disadvantage that, for example, if the targets are present or may exist at long distances and short distances at the same time, the chances of capturing the targets per unit time are reduced and the targets cannot be captured continuously. there were.

In addition, since the distance between the long-distance targets is long, there is a disadvantage that the analysis of the motion of the long-distance targets has a very long time.

The present invention has been made in view of the above problems, a transmitter for generating a frequency f _2, f ₃ to perform the search for the frequency f ₁ and long-distance target for performing search for short-range target, these frequencies And an active sonar device having a transmitter for receiving short distances and a search for a short distance and a long distance at the same time, and improving an opportunity to capture a target per unit time.

[Means for Solving the Problems] To achieve the above object, an active sonar apparatus according to the present invention provides a search signal for a frequency f1 for searching for a short-distance target and a search for a long-distance target. A transmitter that generates a search signal of the frequency f2, f3 to be performed, and a receiver that processes a reception band corresponding to these frequencies f1, f2, f3,
A search signal consisting of a combination of frequencies f1 and f3, and a search signal consisting of a combination of frequencies f1 and f3, and a search signal consisting of a combination of frequencies f1 and f2, followed by a search consisting of a combination of frequencies f1 and f3. The signal is received and the frequencies f1 and f3
After the search signal consisting of the combination of
A transducer for receiving a search signal comprising a combination of
The transducer is provided with a switch for alternately transmitting and receiving the search signal.

The invention of claim (2) provides a transmitter that generates search signals of at least two frequencies, a receiver that processes a reception band corresponding to the plurality of frequencies, and at least a transmitter that generates a search signal corresponding to the plurality of frequencies. A transducer for transmitting search signals of two frequencies alternately at predetermined intervals and receiving the search signals of the plurality of frequencies, and a switch for causing the transducer to alternately transmit and receive the search signal. And performing a long-distance search with a search signal of another frequency while performing a short-distance search with a search signal of any one of the frequencies.

Next, an embodiment of the present invention will be described with reference to FIG.

FIG. 1 shows a block diagram of one embodiment of the present invention. 1
Is a transmitter having three types of transmission frequencies f ₁ , f ₂ and f _3, and a timing generation circuit 2 is connected to the transmitter 1.
3, 4 and 5 in the receiver, the receiver 3 to the transmission frequency f _1, the receiver 4 to the transmission frequency f _2, the receiver 5 processes the received band corresponding to the transmission frequency f _3.

The transmitter 1 and the receivers 3, 4, and 5 are connected to a transmitter / receiver 7 via a switch 6, and a display 8 is connected to the receivers 3, 4, and 5.

In order to search for a target with the active sonar device as described above, the transmitter 1 generates the frequency f ₂ based on the command of the timing generation circuit 2 while the switch 6 is switched to the transmitter 1 side, and the transmission / reception is performed. after giving the transmission power to the vessel 7, providing the transmit power to the transducer 7 to generate the frequency f ₁ subsequently. Then, switch 6 is switched to receivers 3, 4, and 5, and
The receivers 3 and 4 process reception bands corresponding to the frequencies f ₁ and f ₂ , respectively.

Next, switch the predetermined time has elapsed after the switch 6 to the transmitter 1 side, and transmits the frequency f ₃ in place of the frequency f _2, the same operation is repeated thereafter.

In search of these goals, as shown in FIG. 2, together with the transmission frequency f _1, f ₂ is transmitted in the interval T1, performs search for short-range target by the transmission frequency f _1,
The transmission frequency f ₃ which is transmitted at the preceding stage of the transmission is performed a search for long-distance target.

Then, in the next section T2, the transmission frequencies f ₁ and f ₂
There while being transmitted, performs a search for short-range target by the transmission frequency f _1, performs the search for long distance target by the transmission frequency f ₂ transmitted in the section T1.

FIG. 3 is a timing chart showing another example of the target search method.

Searching method illustrated in this figure, using the transmission frequency f _1, f _2, the transmission frequency f ₁ and f ₂ transmitted alternately at predetermined intervals, while one has searched the short distance the other is always far Is to be searched.

FIG. 4 is also a timing chart showing another example of the target search method.

In the search method shown in this figure, the transmission frequencies f ₁ , f ₂ , f ₃ are sequentially transmitted at predetermined intervals, and while one transmission frequency is searching for a short distance, the remaining transmission frequencies are always for a long distance. It is made to search.

This As has been described [Effect of the Invention] The invention, frequency f _2, f ₃ to perform the search for the frequency f ₁ and long-distance target for performing search for short-range target
, And a receiver only corresponding to the transmission frequencies f ₁ , f ₂ , and f ₃ , so that the search density (effective search time per unit time) for the short-range target and the long-range target By making the search density for the target the same and capturing the target at regular intervals, the number of times the target is detected can be increased, and the analysis can be completed in a short time when performing motion analysis of the target. There is.

[Brief description of the drawings]

FIG. 1 is a block diagram of one embodiment of the present invention, FIG. 2 is a timing chart showing a method of searching for a target according to the above, FIGS. 3 and 4 are timing charts showing another search method, and FIG. This is a timing showing a conventional search method. 1: Transmitter, 3, 4, 5: Receiver

Claims (2)

(57) [Claims] A transmitter for generating a search signal of a frequency f1 for searching for a short-range target and a search signal of frequencies f2 and f3 for searching for a long-range target, and a reception corresponding to these frequencies f1, f2 and f3. A receiver that processes the band, the transmission of the search signal consisting of a combination of the frequencies f1 and f2, f1 and f3 from the transmitter every predetermined period, and the transmission of the search signal consisting of the combination of the frequencies f1 and f2, followed by the frequency A search signal consisting of a combination of f1 and f3 is received, and frequencies f1 and f3
After the search signal consisting of the combination of
An active sonar device comprising: a transmitter / receiver for receiving a search signal comprising a combination of the following: and a switch for causing the transmitter / receiver to alternately transmit and receive the search signal. 2. A transmitter for generating search signals of at least two frequencies, a receiver for processing reception bands corresponding to the plurality of frequencies, and a search signal of at least two frequencies generated from the transmitter. A transmitter and a receiver that alternately transmit the search signal at predetermined intervals and receive search signals of these multiple frequencies, and a switch that causes the transceiver to alternately transmit and receive the search signal. An active sonar device characterized in that while performing a short-distance search with a search signal of any one of the frequencies, a long-distance search is performed with a search signal of another frequency.