CN111512179A

CN111512179A - Underwater detection system and method

Info

Publication number: CN111512179A
Application number: CN201980002890.0A
Authority: CN
Inventors: 费尔南德斯·佩尔斯·瓦昆
Original assignee: Electronic Submarine Co ltd
Current assignee: Electronic Submarine Co ltd
Priority date: 2018-11-29
Filing date: 2019-11-22
Publication date: 2020-08-07
Also published as: WO2020109639A1; ES2763748A1

Abstract

The invention relates to an underwater detection system and method, comprising the following steps: (a) a first underwater device comprising in sequence: (a.1) high frequency active and passive sonars (4) arranged in a fixed manner and/or in a sonar-carrying mode under the vessel and configured for transmitting acoustic signals and receiving sonar echoes; and (a.2) a subsea containment device (5) configured to alert authorized subsea devices of the presence in the confined area; and wherein the system further comprises (b) a second aquatic device comprising: (b.1) a communication device (2), the communication device (2) being configured for establishing a communication interface between the underwater device (4, 5) and the above-water device (1, 2, 3, 6); and (b.2) a marine control device (1) configured to process data acquired by the active and passive sonars (4) and to issue a warning by the underwater prevention device (5) if the presence of an unauthorized underwater device in the confined area is detected.

Description

Underwater detection system and method

Technical Field

The technical field to which the invention belongs is underwater detection systems for detecting divers, manned and unmanned submarines to prevent and monitor the threats that may be presented in commercial ports, naval bases, power stations, drilling platforms, moored vessels, environmental protection areas and floating crashes.

Background

In recent years, international interest has grown in the protection of ports, military and civilian vessels, and infrastructure where underwater threats are critical. This protection requires the use of highly specialized sensors characterized by a high detection probability and a low false alarm probability.

Document ES2076316T3 describes an acoustic sonar system in which the received signal is processed without significant filtering thereof to preserve the high fourier components of the received signal and thereby preserve useful information about the target. This is achieved by using a wideband detector module to demodulate the received signal, thereby eliminating the usual intermediate frequency stage. The module includes a broadband input amplifier, a broadband full-wave detector, and a low-pass active filter having a cutoff frequency of at least 50 kHz.

Document ES2422756T3 describes an autonomous acoustic signal processing system that provides a device capable of autonomously performing a large amount of acoustic signal processing. The systems and methods may be configured to autonomously detect, track, classify, and report the presence of quiet targets (e.g., submarine targets) that may be operating in densely transported areas.

Finally, document ES2159220a1 describes a passive sonar system to avoid collisions with whales including a permanent passive (passive sonar) positioning system that tracks in real time the individual movements of whales, in particular sperm whales, to prevent collisions with all types of ships. The system consists of a series of fixed, passive acoustic buoys with the possibility to arrange active acoustic buoys for calibration, a position analysis software program, a buoy-to-buoy communication system, a shore-to-buoy communication system, an onshore three-dimensional geo-software tracking program, a ship-to-shore communication system and an onboard geo-tracking receiver system. The system can be applied in areas where sea traffic causes collisions with whales, which can cause physical and human damage to shipping companies and endanger the protection of certain whale species.

Disclosure of Invention

The object of the invention is defined according to the claims mentioned below. The underwater detection system of claim 1 is configured for detecting intruders in ships, ports and critical offshore installations. Furthermore, an underwater intruder detection method according to claim 14 is also an object of the invention. The dependent claims describe in detail specific and/or preferred embodiments of the invention.

Specifically, the underwater detection system object of the present invention comprises four basic devices: (a) a first underwater active device for installing high frequency active and passive sonar under a water vessel in a fixed manner and/or in a sonar carrying mode and configured for transmitting acoustic signals and receiving sonar echoes; (b) a second diving device configured for alerting authorized diving elements to the presence of a restricted area; (c) a third marine device configured for establishing a communication interface between devices comprising the system; and (d) a fourth watercraft device for providing a user interface and data processing. This system is modular in its entirety, which facilitates future updates thereof. In addition, it is a lightweight system, which facilitates its transportation and operational deployment; finally, it has a wide coverage.

Further, the object of the underwater detection method of the present invention includes: (a) a step for installing a high-frequency active sonar under water, having the steps of transmitting an acoustic signal and receiving a sonar echo; (b) processing a sonar echo signal; (c) a step of detecting the presence of an underwater element in the confined area; and (d) issuing an underwater warning/alarm when the presence of underwater elements in the confined area is detected.

As described above, the present invention provides a system and method for underwater detection of divers, manned and unmanned submarines, providing protection and monitoring of their threats in commercial ports, naval bases, power stations, drilling platforms, moored vessels, environmentally protected areas and loss of buoyancy, in a more efficient and simpler manner than the systems described in the prior art.

Throughout the description and claims the word "comprise" and variations such as "comprises" and "comprising" are not intended to exclude other technical features, additions, components or steps. Additional objects, advantages and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The following examples and figures are provided by way of illustration and are not intended to limit the present invention. Moreover, the invention covers all possible combinations of the specific and preferred embodiments indicated herein.

Drawings

A series of drawings that will help to better understand the invention and that will explicitly relate to the embodiments of said invention presented as non-limiting examples thereof will be described very briefly below.

FIG. 1 shows a diagram of an underwater detection system object of the present invention.

Detailed Description

As shown in fig. 1, the system object of the present invention includes a marine device (1 to 3 and 6) and an underwater device (4, 5). In a first embodiment, an underwater apparatus includes high frequency active and passive sonar (4) disposed underwater at a fixed point and configured for transmitting acoustic signals and receiving sonar echoes. In a second practical embodiment, which is arranged in sonar piloting mode under the vessel, with flexible lines under the hull of the vessel, is a novel aspect of this type of sonar, which is typically mounted at a fixed point or suspended on a moored or anchored vessel (when not underway).

The underwater device comprises an underwater preventing device (5) configured to warn of the presence of unauthorized underwater elements in the confined area, and a set of transducers configured to facilitate the understanding of the acoustic voice messages transmitted into the water.

The system of the invention is completed by a water device (1, 2, 3, 6). The water device consists of a water control device (1), a communication device or an interface (2), an underwater cable (3) connected with the active sonar (4) and an amplifier device (6) connected with the underwater device.

The communication means or interface (2) is configured for establishing a communication interface between the devices constituting the system, providing data feed and interface with the underwater devices, and connection with the marine control means (1) using an interface of the ethernet type, with the possibility of wired or wireless connection.

Finally, the system is completed with an above-water control device (1), the above-water control device (1) being configured to provide a user interface and data processing, said system essentially consisting of a computer which can be provided in various configurations depending on the number of connected underwater devices or the desired configuration of the system (portable, for fitting in a ship or cabinet for installation in a control center).

The described system has a number of advantages and features. Thus, due to the emitted acoustic power and the sensitivity and directivity of the hydrophone assembly used, the detection range can reach 1000m depending on the ambient conditions.

With conventional sonar processing techniques in these systems, the control device (1) can detect, track and automatically classify threat contacts. In this manner, when one of the above threats is detected, the trajectory automatically appears, and as a result of the algorithm for evaluating the trajectory behavior, the contacts are also automatically classified and an alert is issued to the operator. Another feature is that the active sonar (4) is configured for transmitting CW and FM pulses, configuring the transmission of the antenna, and establishing appropriate settings in processing the received sonar signals. It also comprises means configured for electronic orientation of the transmitted beam, which allows setting its vertical angle in order to adapt it to the antenna deployment conditions. Finally, a source stage can be provided in the marine device, setting the antenna transmit power from the user interface.

The system has an angular coverage of 90/180/270/360, limits the transmission of energy to the selected sector, and processes echoes received exclusively from the selected sector. In addition, there are alarm suppression areas that can be configured by the operator and that establish areas where received signals are ignored.

The graphical display of distance and azimuth positions the threat with high accuracy by displaying the tracking results on a graphical map. The system provides an integrated electronic chart based on client requirements.

Another feature of the system is that it allows integration of multiple subsea devices in a common control device (1), covering a larger or more complex area where the common control arrangement is maintained.

The system of the invention also makes use of the same underwater sonar device (4), slightly modified in the fixed system and supported by the same processing software with different configurations in the control device (1), thus facilitating different modes of deployment (seabed, harbour, moored vessel). Furthermore, the system allows to work as an autonomous system or to be integrated in a monitoring system and to forward status information and alarms in the system to a security control system via an ethernet interface for start-up and autonomous operation.

Physically speaking, the present invention employs a smaller size, lightweight, low maintenance device that can be provided in air in a configuration (individual weight per device) of no more than 40 kg.

In a particular embodiment, the system implements available wireless communication protocols as an option between the intermediate communication device (2) and the control device (1), replacing wired ethernet interfaces and avoiding the need for complex wiring according to installation.

In another particular embodiment, the system integrates a plurality of sensors to compensate for any movement of the subsea installation as part of the installation's components and to facilitate compensation for its movement (particularly for suspended deployment modes).

In another particular embodiment, the system comprises means configured for recording and transshipping digital data by means of an internal hard disk drive that allows recording of the data digitized by the antenna and is capable of processing such data as input sonar, facilitating the task of viewing alarms detected during the recording period.

The system is configured with three levels of system operational testing, including a first level for reporting the status of components (availability, temperature sensors, etc.). A second stage that evaluates the signal received at the passive stage, and a third stage that performs transmit and receive loop verification. All of this is performed at the active subsea device level and is controlled by and reported to the user interface device.

Finally, the system incorporates an integrated operator training mode provided as an option in combination with a pre-recorded signal that reproduces various scenes of interest. In another particular embodiment, the system includes acoustic performance prediction as an option and is based on internationally recognized prediction models implemented according to system characteristics.

Claims

1. An underwater detection system, comprising: (a) a first underwater device comprising in sequence: (a.1) high frequency active and passive sonars (4), said high frequency active and passive sonars (4) being arranged under a ship in a fixed manner and/or in a sonar-carrying mode and being configured for transmitting acoustic signals and receiving said sonar echoes; and (a.2) underwater preventing means (5) configured to alert authorized underwater components to the presence in the restricted area; (b) a second watercraft device, the watercraft device comprising: (b.1) a communication device (2), the communication device (2) being configured for establishing a communication interface between the underwater device (4, 5) and the above-water device (1, 2, 3, 6); and (b.2) a marine control device (1) configured to process the data acquired by the active and passive sonars (4) and to issue a warning by the underwater preventing device (5) if the presence of an unauthorized underwater element in a restricted area is detected.

2. The system according to claim 1, wherein the underwater preventing device (5) is configured for alerting an unauthorized underwater device to the presence in a restricted area and comprises a set of transducers configured for facilitating the understanding of an acoustic voice message transmitted into the water.

3. The system according to any of the preceding claims, wherein the communication device (2) is configured for establishing a communication interface between the devices constituting the system, providing data feed and interface with the underwater devices, and connecting with the topside control device (1) with an interface of the ethernet type, wired or wireless connection being possible.

4. The system according to any one of the preceding claims, wherein the marine control device (1) is configured for providing the user interface and data processing, and comprises at least one computer configured for detecting, tracking and automatically classifying a threat's contact, such that when a threat is detected, a trajectory automatically occurs, and as a result of an algorithm for evaluating the trajectory behavior, the contact is automatically classified and an alarm is issued to an operator.

5. The system according to any one of the preceding claims, wherein the active and passive sonars (4) are configured for transmitting CW and FM pulses, configuring the transmission of the antenna, and establishing appropriate settings in processing the received sonar signals; and wherein it further comprises means configured for electronic orientation of the transmitted beam, which allows setting its vertical angle in order to adapt it to the antenna deployment conditions; furthermore, a source stage may be provided in the marine device, wherein the antenna transmission power from the user interface is set.

6. The system of any of the preceding claims, comprising an angular coverage of 90 °/180 °/270 °/360 °, limiting the energy transmission to a selected sector, and processing echoes received only from the selected sector; and wherein there is also a warning suppression area that can be configured by the operator and that establishes an area in which the received signal is ignored.

7. The system of any one of the preceding claims, wherein the graphical display of distance and azimuth allows the threat to be located with high accuracy using the tracking results displayed on a graphical map; and wherein the integrated electronic chart is provided to the system based on previous demand.

8. The system according to any of the preceding claims, wherein the system implements a wireless communication protocol that can be used as an option between the intermediate communication device (2) and the control device (1), replacing the wired ethernet interface and avoiding the need for complex wiring depending on the installation.

9. A system according to any preceding claim, wherein the system incorporates a plurality of sensors to compensate for any movement of the underwater device, as part of the device components, and to facilitate compensation for movement of the underwater device.

10. A system according to any preceding claim, comprising means configured for recording and transshipping digital data by means of an internal hard disk drive which allows recording of data digitised by the antenna and which is capable of processing such data as input sonar, thereby facilitating the task of viewing alerts detected during the recording period.

11. The system of any preceding claim, comprising three system operation test stages, a first stage for reporting the status of the component, a second stage for evaluating signals received at the passive stage, and a third stage for performing transmit and receive loop validation; wherein all stages are performed under the active subsea device level and are controlled and reported to the user interface device.

12. The system according to any of the preceding claims, comprising an integrated operator training mode provided as an option in combination with a pre-recorded signal reproducing various scenes of interest.

13. The system of any preceding claim, comprising acoustic performance prediction as an option and provided based on an internationally recognised predictive model implemented for being set as a feature of the system.

14. A method of underwater detection implemented in a system according to any one of claims 1 to 13, characterized in that the method comprises: (a) a step of placing a high frequency active sonar and including a step of emitting an acoustic signal and receiving the sonar echo; (b) processing a sonar echo signal; (c) a step of detecting the presence of an underwater element in the confinement region; and (d) issuing an underwater warning to underwater components detected in the confined area.