A fiber grating hydrophone towed array monitoring system

Abstract

The present invention discloses a fiber grating hydrophone towed array monitoring system, which relates to the field of fiber optic sensing, including a watertight electronic cabin, a transmission optical cable and a fiber grating towed linear array. The watertight electronic cabin has an outer shell, and a plurality of functional modules are loaded in the outer shell. The functional modules are connected to a power supply and communication interface and an optical cable transmission interface provided on the outer shell. The power supply and communication interface supplies power and communicates to each functional module. The optical cable transmission interface is connected to the fiber grating towed linear array through a transmission optical cable to realize the transmission of optical signals between the watertight electronic cabin and the fiber grating towed linear array; the fiber grating towed linear array is used to receive external target signals. The present invention adopts the fiber grating towed linear array technology to realize a thin-diameter towed array. Through the low-power consumption and small-size design, the transmitting and receiving dry-end equipment is moved from the unmanned platform cabin to the outside of the cabin through the electronic cabin, avoiding the problem of the towed linear array cable passing through the cabin.

Description

Technical Field

[0001] The invention relates to the field of optical fiber sensing, and in particular to a fiber grating hydrophone towed array monitoring system. Background Art

[0002] Maritime unmanned platforms can carry a variety of sensors and combat modules to perform underwater navigation and combat missions such as warning, reconnaissance, surveillance, tracking and anti-submarine. They have the advantages of flexible operations, rapid response, strong concealment, and the ability to repeatedly perform high-risk combat missions. They have attracted much attention from navies of various countries and have high tactical value and military application prospects in the fields of underwater reconnaissance, early warning detection, etc.

[0003] The application of unmanned platforms in the field of underwater acoustic detection has promoted the development of underwater acoustic detection equipment technology suitable for unmanned platforms. Towed linear array sonar is an important part of underwater reconnaissance and detection systems. The towed linear array is towed away from the carrying platform and is free from platform noise interference. It is an important means of underwater information acquisition in contemporary underwater warfare. At present, three-dimensional imaging sonar, mine detection sonar, forward-looking sonar, scanning sonar, etc. are widely used in unmanned platforms, and the application of towed linear array sonar on unmanned platforms is mostly in the research stage. For large and super-large offshore unmanned platforms, due to their strong load capacity and large size, the existing towed linear array sonar can be carried after adaptive modification. However, for small and medium-sized unmanned platforms, due to limited load space and volume, higher requirements are placed on the aperture and deployment of the towed linear array. Under the premise of limited space and load capacity of unmanned platforms, the existing towed linear array sonar faces difficulties such as heavy weight, complex release and recovery system, and large installation space requirements. Summary of the invention

[0004] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a fiber Bragg grating hydrophone towed array monitoring system, which has the characteristics of small size and low power consumption. The sensing part has the advantages of no need for power supply, no electronic components, and not susceptible to electromagnetic interference, which can effectively improve the detection ability of the towed linear array to underwater targets. Compared with traditional fiber optic hydrophones, it has the advantages of small size, simple process, and the sensing unit is only the size of one optical fiber, and "series connection is an array". It can be widely used in small-diameter towed arrays of small nuclear boats, unmanned submersibles, etc., effectively solving the limited storage space of towed arrays of small nuclear boats and underwater unmanned vehicles, and the contradiction between the increasing range and the detection distance, and realizing light load, small space carrying and digital transmission.

[0005] The objective of the present invention is achieved through the following technical solutions: This fiber Bragg grating hydrophone towed array monitoring system comprises a watertight electronic cabin, a transmission optical cable and a fiber Bragg grating towed linear array, wherein the watertight electronic cabin has an outer shell, and a plurality of functional modules are loaded in the outer shell, wherein the functional modules are connected to a power supply and communication interface and an optical cable transmission interface arranged on the outer shell, wherein the power supply and communication interface supplies power and communicates to each functional module, and the optical cable transmission interface is connected to the fiber Bragg grating towed linear array through the transmission optical cable, so as to realize the optical signal transmission between the watertight electronic cabin and the fiber Bragg grating towed linear array; and the fiber Bragg grating towed linear array is used to receive external target signals.

[0006] As a further technical solution, the outer shell includes an upper end cover, a lower end cover and a barrel body. The barrel body is a watertight metal cylinder. A sealing ring is used to make the barrel body, the upper end cover and the lower end cover watertight and fixed with screws. The power supply communication interface and the optical cable transmission interface are embedded in the upper end cover.

[0007] As a further technical solution, the functional module includes an optical transceiver module, a signal demodulation module, a signal processing module, a data storage module and a power supply control module; the power supply control module has multiple power supply and control interfaces, and its power supply input end is electrically connected to the power supply communication interface, and the typical value of the input voltage is +24V. Its power supply output end is electrically connected to the optical transceiver module, the signal demodulation module, the signal processing module, and the data storage module respectively to realize power supply.

[0008] As a further technical solution, the optical transceiver module is an optical device integrated module, which is used to provide high-power pump laser to the fiber Bragg grating dragged linear array and simultaneously receive the returned optical signal and perform wavelength division processing. The typical value of the laser wavelength is 980nm or 1480nm, and the typical value of the optical power is greater than 100mW; the optical transceiver module outputs laser to the optical cable transmission interface, and transmits it to the fiber Bragg grating dragged linear array through the transmission optical cable; the power supply control module can control the current of the optical transceiver module, thereby adjusting the optical power of the laser output by the optical transceiver module.

[0009] As a further technical solution, the signal demodulation module uses the FPGA+DSP architecture as a signal processing platform, receives the multiple wavelength optical signals after wavelength division multiplexing by the optical transceiver module, adjusts the optical power, and parses the external target information received by the fiber grating dragged linear array from the optical signal and sends it to the data storage module.

[0010] As a further technical solution, the signal processing module receives the array element target information sent by the signal demodulation module from the data storage module, and sends the target information to the power supply and communication interface by means of broadband warning, target tracking, azimuth and distance measurement, and target line spectrum feature extraction.

[0011] As a further technical solution, the data storage module adopts multicast technology, has data exchange and storage functions, and stores the array data information output by the signal demodulation module.

[0012] As a further technical solution, the fiber Bragg grating drag array uses a flexible tube, the outer diameter of which is typically Several fiber grating hydrophones are arranged in the flexible tube to receive external target signals; the multiplexing mode of the fiber grating hydrophone is wavelength division multiplexing, the typical value of the number of wavelength division multiplexing is 8, and the typical value of the central wavelength interval is 300G.

[0013] The beneficial effects of the present invention are as follows: the fiber Bragg grating towed linear array technology is adopted to realize a thin-diameter towed array, and the transmitting and receiving dry-end equipment is moved from the inside of the unmanned platform cabin to the outside of the cabin through the electronic cabin through a low-power and small-size design, thereby avoiding the problem of the towed linear array cable passing through the cabin, and at the same time, digital transmission of hydrophone signals can be realized, reducing system signal interference, and providing an effective solution to solve the problems of limited space and low load capacity of offshore unmanned platforms. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a structural schematic diagram of the present invention.

[0015] Figure 2 It is a flowchart of the workflow of the present invention.

[0016] Explanation of the reference numerals: watertight electronic compartment 10, outer shell 11, upper end cover 111, lower end cover 112, barrel body 113, power supply and communication interface 114, optical cable transmission interface 115, optical transceiver module 12, signal demodulation module 13, signal processing module 14, data storage module 15, power supply control module 16, transmission optical cable 20, fiber Bragg grating towed linear array 30, fiber Bragg grating hydrophone 31. DETAILED DESCRIPTION

[0017] The present invention will be described in detail below with reference to the accompanying drawings:

[0018] Example: As shown in the attached Figure 1As shown, the fiber Bragg grating hydrophone towed array monitoring system includes a watertight electronic cabin 10, a transmission optical cable 20 and a fiber Bragg grating towed linear array 30. The watertight electronic cabin 10 is a sealed structure with an outer shell 11, and the outer shell 11 includes an upper end cover 111, a lower end cover 112 and a barrel 113. The barrel 113 is a watertight metal cylinder. A sealing ring is used between the barrel 113 and the upper end cover 111 and the lower end cover 112 to make them watertight and fixed with screws. The upper end cover 111 is embedded with a power supply and communication interface 114 and an optical cable transmission interface 115. The outer shell 11 is loaded with several functional modules, including an optical transceiver module 12, a signal demodulation module 13, a signal processing module 14, a data storage module 15 and a power supply control module 16; each functional module is connected to a power supply communication interface 114 and an optical cable transmission interface 115 provided on the outer shell 11, the power supply communication interface 114 supplies power and communication to each functional module, and the optical cable transmission interface 115 is connected to a fiber grating drag array 30 through a transmission optical cable 20 to realize optical signal transmission between the watertight electronic cabin 10 and the fiber grating drag array 30; the fiber grating drag array 30 is used to receive external target signals.

[0019] Preferably, if Figure 2 As shown, the power supply control module 16 has multiple power supply and control interfaces, its power supply input end is electrically connected to the power supply communication interface 114, the typical input voltage is +24V, and its power supply output end is electrically connected to the optical transceiver module 12, the signal demodulation module 13, the signal processing module 14, and the data storage module 15 respectively to realize power supply.

[0020] The optical transceiver module 12 is an optical device integrated module, which is used to provide high-power pump laser to the fiber Bragg grating dragged linear array 30 and simultaneously receive the returned optical signal and perform wavelength division processing. The typical value of the laser wavelength is 980nm or 1480nm, and the typical value of the optical power is greater than 100mW; the optical transceiver module 12 outputs laser to the optical cable transmission interface 115, and transmits it to the fiber Bragg grating dragged linear array 30 through the transmission optical cable 20; the power supply control module 16 can control the current of the optical transceiver module 12, thereby adjusting the optical power of the laser output by the optical transceiver module 12.

[0021] The signal demodulation module 13 uses the FPGA+DSP system architecture as a signal processing platform, receives the multiple wavelength optical signals after wavelength division multiplexing by the optical transceiver module 12, adjusts the optical power, and parses the external target information received by the fiber grating dragged linear array 30 from the optical signal and sends it to the data storage module 15.

[0022] The data storage module 15 adopts multicast technology, has data exchange and storage functions, and stores the array data information output by the signal demodulation module 13 .

[0023] The signal processing module 14 receives the array element target information sent by the signal demodulation module 13 from the data storage module 15, and sends the target information such as the direction, distance, target type, etc. to the power supply and communication interface 114 through broadband warning, target tracking, direction and distance measurement, and target line spectrum feature extraction.

[0024] The fiber Bragg grating towed array 30 uses a flexible tube with zero buoyancy design, and its outer diameter is typically Several fiber grating hydrophones 31 are arranged in the flexible tube to receive external target signals. By absorbing the pump laser sent by the optical transceiver module 12, the laser with a wavelength of 1550nm is stimulated to modulate the hydroacoustic signal to the wavelength of the array element. The multiplexing mode of the fiber grating hydrophone 31 is wavelength division multiplexing. The typical value of the number of wavelength division multiplexing is 8, and the typical value of the center wavelength interval is 300G. It can be expanded by space division multiplexing, that is, increasing the number of optical fibers.

[0025] It is understandable that, for those skilled in the art, any equivalent replacement or change to the technical solution and inventive concept of the present invention should fall within the protection scope of the claims attached to the present invention.

Claims

1. A fiber grating hydrophone towed array monitoring system, characterized in that: The invention comprises a watertight electronic cabin (10), a transmission optical cable (20) and a fiber Bragg grating towed array (30). The watertight electronic cabin (10) has an outer shell (11). A plurality of functional modules are loaded in the outer shell (11). The functional modules are connected to a power supply and communication interface (114) and an optical cable transmission interface (115) provided on the outer shell (11). The power supply and communication interface (114) supplies power to and communicates with each functional module. The optical cable transmission interface (115) is connected to the fiber Bragg grating towed array (30) via the transmission optical cable (20) to realize optical signal transmission between the watertight electronic cabin (10) and the fiber Bragg grating towed array (30). The fiber Bragg grating towed array (30) is used to receive external target signals. The outer shell (11) comprises an upper end cover (111), a lower end cover (112) and a barrel body (113); the barrel body (113) is a watertight metal cylinder; a sealing ring is used between the barrel body (113) and the upper end cover (111) and the lower end cover (112) to ensure watertightness and to fix the barrel body (113) with screws; the power supply communication interface (114) and the optical cable transmission interface (115) are embedded in the upper end cover (111); The functional module comprises an optical transceiver module (12), a signal demodulation module (13), a signal processing module (14), a data storage module (15) and a power supply control module (16); the power supply control module (16) has a plurality of power supply and control interfaces, a power supply input end thereof is electrically connected to the power supply communication interface (114), a typical input voltage value is +24V, and a power supply output end thereof is electrically connected to the optical transceiver module (12), the signal demodulation module (13), the signal processing module (14) and the data storage module (15) respectively to realize power supply; The optical transceiver module (12) is an optical device integrated module, used for providing high-power pump laser to the fiber Bragg grating dragged linear array (30) and receiving the returned optical signal and performing wavelength division processing, the typical value of the laser wavelength is 980nm or 1480nm, and the typical value of the optical power is greater than 100mW; the optical transceiver module (12) outputs laser to the optical cable transmission interface (115), and transmits it to the fiber Bragg grating dragged linear array (30) through the transmission optical cable (20); the power supply control module (16) can perform current control on the optical transceiver module (12), thereby adjusting the optical power of the laser output by the optical transceiver module (12); The signal demodulation module (13) uses an FPGA+DSP system architecture as a signal processing platform, receives the multiple wavelength optical signals after wavelength division multiplexing by the optical transceiver module (12), performs optical power adjustment, and parses the external target information received by the fiber grating towed linear array (30) from the optical signal and sends it to the data storage module (15); The signal processing module (14) receives the array element target information sent by the signal demodulation module (13) from the data storage module (15), and sends the target information to the power supply and communication interface (114) by means of broadband warning, target tracking, azimuth and distance measurement, and target line spectrum feature extraction; The fiber grating towed linear array (30) adopts a flexible tube, the outer diameter of which is typically Ø20 mm. A plurality of fiber grating hydrophones (31) are arranged in the flexible tube for receiving external target signals. The fiber grating hydrophones (31) are multiplexed in wavelength division multiplexing, the number of wavelength division multiplexing is typically 8, and the central wavelength interval is typically 300G.

2. The fiber Bragg grating hydrophone towed array monitoring system according to claim 1, characterized in that: The data storage module (15) adopts multicast technology, has data exchange and storage functions, and stores array data information output by the signal demodulation module (13).

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