JP2001338399A - Sea area monitoring system and sea area monitoring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sea area monitoring device which can quickly and accurately detect doubtful ships (poaching ships) to prevent the poaching and also to decrease the poaching damage. SOLUTION: A sea area is monitored according to the acoustic information which are collected by an underwater microphone and a secret sound transmitter is attached to every regular ship of regular sea area workers to transmit the prescribed frequency (secret sounds) for discriminating easily and quickly the poaching ships from regular ones. The transmission frequency of the secret sound transmitter can be changed for preventing production of a spurious secret sound transmitter.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sea area monitoring system and apparatus, and more particularly to a sea area monitoring system and apparatus effective for monitoring a poaching boat or the like illegally entering a fishing ground.

[0002]

2. Description of the Related Art A conventional sea area monitoring system for monitoring poaching boats generally monitors and records video cameras or infrared cameras installed on land in order to monitor approach and intrusion of poaching boats to fishing grounds. .

[0003]

However, in the case of a conventional camera-based sea area monitoring system, it is possible to monitor a relatively long distance in the daytime. There was a problem that the range was considerably limited. Therefore, it is conceivable to install bright lighting, but in this case, there is a possibility that the fish and the like in the fishing ground will be adversely affected. Therefore, there is a demand for a monitoring system using a stable monitoring information source regardless of day and night. Also, despite the complicated image processing, the construction of feature extraction algorithms, the construction of a fishing boat database, and the digital signal processing required to determine whether a ship is a suspicious ship using a conventional camera, the possibility of erroneous determination is small. There was a mistake.

[0004] It is an object of the present invention to provide a monitoring system and an apparatus capable of stably monitoring day and night.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a receiving means for capturing sound information emitted from an object to be monitored, for example, a fishing boat or a suspicious boat, and the sound received by the receiving means. Monitoring means for monitoring information as a monitoring information source is provided. Since underwater acoustic information propagates over a wide range, it is possible to detect the approach of a fishing ground by a ship from a long distance. In addition, the distinction between a suspicious ship and a regular marine work vessel can be easily and reliably made by attaching an acoustic transmitter that emits a predetermined secret sound to the regular marine work vessel. It is possible to do.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS. The numbers in parentheses in the text correspond to the step numbers in FIG. In FIG. 1, reference numeral 1 denotes a secret sound transmission device towed by a ship, the device includes a specified frequency generator 3 for generating an electric signal (specified frequency) for transmitting a secret sound, and a time interval of the secret sound transmission. And a sound transmitting unit that converts the electric signal of the secret sound into an acoustic signal and transmits the signal to the sea as a secret sound. 5 is a receiving device for receiving a secret sound, the receiving device is installed under the sea, includes a microphone that captures acoustic information, and a receiving unit 6 that converts the acoustic signal into an electric signal;
A classification unit 7 for classifying a signal from the receiving device 5 into a ship sound, a secret sound, and a noise; a determination unit 8 for determining whether a suspicious ship is based on a timer and the presence or absence of a secret sound; It includes a timer unit 9 that measures the elapsed time simultaneously with the detection of the ship sound and an alarm generation unit 10 that generates an alarm signal based on a signal from the determination unit 8. The receiving device main body 5 is, for example, a monitoring hut made on land and installed there, or installed on a ship side. Receiver main body 5 and receiver 6
Is connected with a cable or the like.

[0007] A regular work boat (ship) approaches the working sea area while towing the secret sound transmitting device 1 for reproducing a predetermined frequency. The specified frequency generating unit 3 sends a frequency reproduction signal to the sound transmitting unit 4 at predetermined time intervals measured by the timer unit 2 based on a predetermined frequency setting. Frequency sound (secret sound)
Outgoing.

At this time, the receiving device 5 operates as shown in FIG. That is, the receiving device 5 that has received the acoustic signal including the ship sound (running sound, screw sound, etc.) and the secret sound,
The acoustic signal is received by the receiving unit 6 and converted into an electric signal (step 11). This electric signal is sent to the classification unit 7,
The classification unit 7 performs frequency classification (step 12). The electric signal separated into the frequency components is further sent to the determination unit 8. The classification unit 7 detects a ship sound from the acoustic signal, and at the same time, sends a drive signal to the timer unit 9, and the timer unit 9 measures an elapsed time after receiving the ship sound (step 13). The determination unit 8 extracts a predetermined frequency component based on the frequency-separated electric signal sent from the classification unit 7 (Step 14). Thus, the secret sound is decoded. At the same time, the elapsed time measured by the timer unit 9 is monitored. In the case of a regular sea area work boat, the elapsed time measured by the timer unit 9 is detected by the discriminating unit 8 by detecting a frequency component that is a secret sound within a preset time.
The generation of the alarm request signal to the alarm generation unit 10 is stopped, and the generation of the alarm is stopped. When the discriminating unit 8 detects a frequency component that is a secret sound, the timer unit 9 is reset and the elapsed time is set to 0 (step 15). While the work boat continues working, the secret sound transmitter 1 emits a secret sound within a predetermined time interval. Thus, no alarm is generated in the case of a regular work boat.

Next, in the case of a ship having no secret sound transmitter 1, the receiver 5 performs the following operation. The receiver 5 receives an acoustic signal composed of the sound of a ship, and converts the acoustic signal into an electric signal by the receiving unit 6 (step 11). This electric signal is sent to the classification unit 7, and the classification unit 7 performs frequency classification (step 12). The electric signal separated into the frequency components is further sent to the determination unit 8. In addition, the classification unit 7 detects a ship sound from the acoustic signal and, at the same time, sends a driving signal to the timer unit 9,
The timer section 9 measures the elapsed time from receiving the ship sound (step 13). The discriminating unit 8 attempts to extract a predetermined frequency component based on the frequency signal sent from the classifying unit 7 (step 14). Not judge. At the same time, the elapsed time measured by the timer unit 9 is
Since the secret sound cannot be detected even after the preset time has elapsed, the timeout signal is detected by the determination unit 8 after the specified time has elapsed.
(Step 16). The determination unit 8 generates an alarm request signal to the alarm generation unit 10, and the alarm generation unit 10 generates an alarm (Step 17). To prepare for the next detection, the determination unit 8 resets the timer unit 9 and sets the elapsed time to 0 (step 15).

The secret sound transmitter 1 can arbitrarily change the transmission frequency in order to prevent forgery of the secret sound transmitter. If the transmission frequency is not changed, set the transmission signal ON, OF
It is also possible to transmit a secret sound by encoding into a binary number similar to the Morse code using F.

[0011]

According to the present invention, a wide sea area can be monitored regardless of day or night. In addition, since it is possible to easily and reliably distinguish between regular vessels and suspicious vessels, quick and correct alarms can be generated, preventing illegal fishing by suspicious boats (poaching boats) and reducing the damage caused by poaching. Can be expected.

[Brief description of the drawings]

FIG. 1 is a block diagram for explaining a basic structure of a sea area monitoring system and apparatus according to the present invention.

FIG. 2 is a flowchart for explaining the operation of the sea area monitoring system and apparatus of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Secret sound transmission apparatus 2 ... Timer part 3 ... Regular frequency generation part 4 ... Transmission part 5 ... Receiving apparatus 6 ... Receiving part 7 ... Classification part 8 ... Timer unit 9 ・ ・ ・ Discrimination unit 10 ・ ・ ・ Alarm generation unit

Claims (5)

[Claims] 1. A sea area monitoring system in which a sound receiving unit is installed in the sea, and the sound information from the sound receiving unit is captured to monitor an object to be monitored. Providing a sound transmitting device for transmitting, a receiving unit for converting the acoustic signal into an electric signal on the monitoring device side, a classifying unit for classifying a signal from the receiving unit into a ship sound, a secret sound, and noise, and a constant by the ship sound A timer unit that operates for a time, a discriminating unit that discriminates between a marine vessel and a suspicious vessel based on the presence of a timer and a secret sound, and an alarm generating unit that generates an alarm signal based on a signal from the discriminating unit. Sea area monitoring system. 2. The sound receiving section comprises a microphone,
The sea area monitoring system according to claim 1, wherein the monitoring device is installed on the ship or land. 3. The discriminating unit according to claim 1, when there is a secret sound within a certain time during the operation of the timer, judges that the ship is a regular work vessel in the sea area, and when there is no secret sound within a certain time during the operation of the timer. Is a sea area surveillance system that determines a suspicious ship. 4. A sea area monitoring system according to claim 1, wherein the acoustic transmitter for transmitting a secret sound transmits a predetermined single frequency or a plurality of frequencies and can change a transmission frequency. 5. A sea area monitoring device in which a sound receiving unit is installed in the sea, and the sound information from the sound receiving unit is captured to monitor a monitoring target, and is provided on a ship side of a regular sea area worker. A receiving unit that converts an acoustic signal from an acoustic transmission device that emits a secret sound into an electric signal, a classifying unit that classifies the signal from the receiving unit into a ship sound, a secret sound, and noise, and operates for a fixed time by the ship sound A sea area monitoring device comprising: a timer section; a judgment section for judging a regular sea area work boat and a suspicious ship based on the presence of a timer and a secret sound; and an alarm generation section for generating an alarm signal based on a signal from the judgment section. .