Small integrated underwater acoustic detection system based on phi-OTDR (Optical Time Domain Reflectometer)

Abstract

The utility model relates to the field of distributed optical fiber underwater acoustic detection, in particular to a small-sized integrated underwater acoustic detection system based on a phi-OTDR (Optical Time Domain Reflectometer). The distributed optical fiber underwater acoustic detection system based on the phi-OTDR comprises an underwater acoustic detection system cover plate, an underwater acoustic detection system shell, a waterproof aviation plug and an optical fiber interface, wherein the waterproof aviation plug and the optical fiber interface are arranged on the underwater acoustic detection system shell; the underwater sound detection system cover plate and the shell are fixed through screws; a groove is formed in the upper wall surface of the underwater acoustic detection system shell and is used for placing a water sealing strip; and an optical fiber waterproof sleeve is sleeved outside the optical fiber interface. According to the utility model, waterproof protection is carried out between the cover plate and the housing, and at the waterproof aviation plug and the optical fiber interface, and the outer wall of the system housing is provided with the reinforcing ribs, so that the system is ensured to have enough water tightness and pressure resistance underwater, and is suitable for multi-scene application carrying of a shore base, a ship base, a tower base and the like in a complex marine environment.

Description

Technical Field

[0001] This invention belongs to the field of distributed fiber optic underwater acoustic detection technology, and in particular, a small integrated underwater acoustic detection system based on a phase-sensitive optical time-domain reflectometer (Φ-OTDR). Through optimized structural design, this system achieves efficient acoustic wave detection in the underwater environment and is suitable for multiple applications such as marine safety, maritime rescue, ecological protection, and fisheries development. Background Technology

[0002] Acoustic wave detection is an important means of underwater information acquisition. Among them, underwater acoustic waves, due to their ability to carry information and propagate over long distances underwater, have become the core carrier of underwater detection. Traditional underwater acoustic detection technology mainly relies on piezoelectric sensors, but they have limitations such as large size, high power consumption, and weak anti-interference ability, making it difficult to meet the high-precision and distributed requirements of modern marine exploration.

[0003] In recent years, distributed fiber-optic underwater acoustic sensing technology based on phase-sensitive optical time-domain reflectometers (Φ-OTDR) has gradually become a research hotspot due to its advantages such as high sensitivity, long-distance detection, and strong anti-interference capability. This technology utilizes the phase modulation effect of Rayleigh scattering in optical fibers to achieve spatially continuous sound field measurement, and also features easy networking and passive operation at the wet end.

[0004] However, existing commercial Φ-OTDR devices typically employ a standard rack-mount structure, resulting in a bulky size that fails to meet the deployment requirements for miniaturized and lightweight underwater equipment. Furthermore, existing systems lack specific designs for the high-pressure and corrosive underwater environment, exhibiting insufficient waterproof sealing and pressure resistance, making long-term reliability difficult to guarantee. Simultaneously, underwater equipment must avoid using cooling fans to prevent noise interference, but the enclosed environment leads to heat accumulation, affecting device stability and severely limiting its application in the marine field. Utility Model Content

[0005] This invention addresses the problems of large size, poor underwater adaptability, and the contradiction between heat dissipation and noise in existing Φ-OTDR underwater acoustic detection systems. It proposes a small integrated underwater acoustic detection system based on a phase-sensitive optical time-domain reflectometer (Φ-OTDR). Through compact structural design, multi-layer waterproof sealing, fanless heat dissipation scheme, and electromagnetic isolation layout, the system achieves miniaturization while improving underwater environmental adaptability and detection reliability.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A small, integrated underwater acoustic detection system based on Φ-OTDR, characterized by comprising:

[0008] The shell (2) and the detachable cover plate (1) are integrally formed. The shell (2) adopts a biomimetic streamlined design. The cover plate (1) and the shell (2) are connected to the vacuum level by evenly distributed screws (5). The contact surface is provided with stepped double grooves (6) and embedded with nanocomposite sealing strips (7).

[0009] A waterproof aviation plug (3) and an optical fiber interface (4) are provided on the housing (2); wherein the waterproof aviation plug (3) adopts a self-sealing rotary locking structure, and the optical fiber interface (4) adopts a magnetic quick connection structure, and is externally fitted with an optical fiber waterproof sleeve (8).

[0010] Furthermore, the outer wall of the shell (2) is provided with biomimetic honeycomb reinforcing ribs (9), the thickness of which varies in a gradient, gradually increasing from top to bottom, with a thickness range of 3-8 mm, to ensure the pressure resistance of the shell (2) underwater. A distributed fiber optic sensor array is embedded for real-time monitoring of shell deformation.

[0011] Furthermore, the interior of the reinforcing rib (9)

[0012] Furthermore, the waterproof aviation plug (3) adopts an intelligent identification multi-protocol interface, integrating power, data and signal transmission functions into one.

[0013] Furthermore, the interface has a self-drying chamber inside, with a built-in miniature humidity sensor and an electric heating dehumidification device. A data transmission line (10) is led out from the tail.

[0014] Furthermore, the shell (2) adopts a three-dimensional support structure, including: a support column (11) at the bottom with internal threads; and a shelf (12) fixed above the support column (11).

[0015] Furthermore, the suspended layer (12) is made of superconducting material to form an electromagnetic shielding cabin; the lower optical cabin is equipped with an adaptive optics platform that can adjust the position of optical devices in real time; the upper electronic cabin adopts a modular plug-in design, and each functional module is connected without solder joints through quantum dot conductive adhesive.

[0016] Furthermore, the optical compartment is equipped with a heat-conducting pad to cover the optical components and transfer heat to the housing (2) for heat dissipation; the electronic compartment is equipped with a heat-conducting pad to cover the electronic components and transfer heat to the cover plate (1) and the shelf plate (12) for heat dissipation.

[0017] Furthermore, the system adopts a new energy power supply solution, including:

[0018] The shell surface integrates a flexible solar film and a water flow energy harvesting device;

[0019] The internal intelligent energy management module automatically optimizes energy distribution.

[0020] Beneficial effects

[0021] This invention provides a small, integrated underwater acoustic detection system based on Φ-OTDR. It has the following advantages:

[0022] (1) The small integrated underwater acoustic detection system based on Φ-OTDR is waterproofed between the cover plate and the housing, at the waterproof aviation plug and the fiber optic interface in order to meet the water use requirements. Furthermore, the outer wall of the system housing is reinforced with ribs to ensure that the system has sufficient water tightness and pressure resistance underwater.

[0023] (2) The small integrated underwater acoustic detection system based on Φ-OTDR isolates the optical part from the electrical part through the layer plate, and conducts the heat of the device into the housing and cover plate through the thermal pad to prevent heat accumulation, thereby protecting the device. Attached Figure Description

[0024] To more clearly illustrate the embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0025] The structures, proportions, sizes, etc. illustrated in this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed herein, and are not intended to limit the implementation conditions of this utility model. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that this utility model can produce, should still fall within the scope of the technical content disclosed in this utility model.

[0026] Figure 1 This is a three-dimensional structural diagram of the small integrated underwater acoustic detection system based on Φ-OTDR of this utility model.

[0027] Figure 2 This is a schematic diagram of the internal structure of the small integrated underwater acoustic detection system based on Φ-OTDR of this utility model.

[0028] Figure 3 This is a schematic diagram of the shell reinforcing ribs in the small integrated underwater acoustic detection system based on Φ-OTDR of this utility model.

[0029] Figure 4 This is a schematic diagram of the central support column of the small integrated underwater acoustic detection system based on Φ-OTDR of this utility model.

[0030] Legend:

[0031] 1. Cover plate; 2. Housing; 3. Waterproof aviation connector; 4. Fiber optic interface; 5. Screw; 6. Groove; 7. Water seal strip; 8. Fiber optic waterproof sleeve; 9. Reinforcing rib; 10. Data transmission line; 11. Support column; 12. Shelf. Detailed Implementation

[0032] The embodiments of this utility model will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and should not be construed as limiting the scope of this utility model.

[0033] Example 1

[0034] like Figure 1 As shown, a small integrated underwater acoustic detection system based on Φ-OTDR includes:

[0035] The shell 2 is integrally formed from high-strength aluminum alloy (such as 6061-T6) and the surface is anodized to improve corrosion resistance.

[0036] Detachable cover plate 1: It is fastened to the shell 2 by titanium alloy screws 5. The contact surface is provided with stepped double grooves 6 and embedded nano composite sealing strips 7 to ensure sealing performance under high pressure underwater environment.

[0037] In this embodiment, to prevent water ingress and damage to internal components when the system and the optical fiber under test are placed underwater for acoustic measurement, waterproof aviation connectors 3 are used for the electrical connections. The optical fiber interface 4 on the system's side wall is externally fitted with a waterproof optical fiber sleeve 8 to ensure continued airtightness after long-term use. Furthermore, to prevent deformation of the casing due to underwater pressure when the underwater acoustic detection system is placed underwater, the casing and cover plate are thickened, and a series of reinforcing ribs 9 are provided on the outer wall and bottom surface of the casing to ensure sufficient pressure resistance of the system underwater. Figure 3 As shown. The thickness of the reinforcing rib 9 varies gradually from 3mm at the top to 8mm at the bottom to enhance pressure resistance (pressure resistance rating ≥10MPa).

[0038] The waterproof aviation plug 3 has 10 pins, with one pin leading out to the data transmission line 10. The data transmission line 10 is connected to the computer's network port to achieve real-time data transmission via Ethernet. The waterproof aviation plug (3) is equipped with a miniature electric heating dehumidifier to prevent condensation from affecting the circuit.

[0039] like Figure 2 and Figure 4 As shown, the internal structure of the shell employs a three-dimensional support structure:

[0040] A support column 11 is provided at the bottom, and the support column 11 has internal threads. A shelf 12 is fixedly installed above the support column 11. The shelf 12 isolates the electrical part from the optical part. Optical parts are fixedly installed below the shelf 12, and electrical parts are fixedly installed above the shelf 12, in order to avoid electromagnetic crosstalk.

[0041] In this embodiment, to ensure the underwater acoustic detection system meets water usage requirements, no cooling fan is installed inside the housing 2. Therefore, heat dissipation is primarily achieved through heat transfer. The optical components below the shelf 12 transfer heat to the housing 2 via thermal pads, while the electrical components above the shelf 12 transfer heat to the system cover 1 and the shelf 12 itself via thermal pads. The shelf 12 then couples the heat to the housing 2. This design effectively dissipates heat without a fan, preventing heat accumulation and damage to the components.

[0042] System noise level is an important indicator for evaluating the performance of a Φ-OTDR system. System noise level refers to the probabilistic statistics of the system noise power distribution per unit frequency. The lower the system noise level, the less likely the target is to be overwhelmed by noise. In this embodiment, the underwater acoustic detection system is a sealed device with no airflow inside the system housing 2, which reduces the system's own noise interference and improves the system's detection performance.

[0043] In this embodiment, the optical fiber under test is connected to the Φ-OTDR system and submerged underwater after being protected by a waterproof optical fiber sleeve 8. The system uses a new energy power supply method, powered by a flexible solar film integrated on the shell surface and a water flow energy harvesting device. The system is equipped with an intelligent energy management module that automatically optimizes energy distribution. The data transmission line 10 is connected to the network port of the computer, and Ethernet communication is performed by setting an IP address to continuously transmit the Rayleigh scattering signal of the optical fiber under test to the computer, which displays it in real time.

[0044] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A small integrated underwater acoustic detection system based on Φ-OTDR, characterized in that, include: The shell (2) and the detachable cover plate (1) are integrally formed. The shell (2) adopts a biomimetic streamlined design. The cover plate (1) and the shell (2) are connected to the vacuum level by evenly distributed screws (5). The contact surface is provided with stepped double grooves (6) and embedded with nanocomposite sealing strips (7). A waterproof aviation plug (3) and an optical fiber interface (4) are provided on the housing (2); wherein the waterproof aviation plug (3) adopts a self-sealing rotary locking structure, and the optical fiber interface (4) adopts a magnetic quick connection structure, and is externally fitted with an optical fiber waterproof sleeve (8). 2.The Φ-OTDR-based small integrated underwater acoustic detection system according to claim 1, characterized in that: The outer wall of the shell (2) is provided with biomimetic honeycomb reinforcing ribs (9). The thickness of the reinforcing ribs (9) varies in a gradient, gradually increasing from the top to the bottom, with a thickness range of 3-8 mm, to ensure the pressure resistance of the shell (2) underwater. 3.The Φ-OTDR-based small integrated underwater acoustic detection system according to claim 2, characterized in that: The reinforcing rib (9) is embedded with a distributed fiber optic sensor array for real-time monitoring of shell deformation. 4.The Φ-OTDR-based small integrated underwater acoustic detection system according to claim 1, characterized in that: The waterproof aviation plug (3) adopts an intelligent identification multi-protocol interface, integrating power, data and signal transmission functions into one. 5.The miniaturized integrated water acoustic detection system based on Φ-OTDR according to claim 4, characterized in that: The interface has a self-drying chamber, a built-in miniature humidity sensor and an electric heating dehumidification device, and a data transmission line (10) is led out from the tail. 6.The Φ-OTDR based miniaturized integrated underwater acoustic detection system of claim 1, wherein: The shell (2) has a three-dimensional support structure inside, including: a support column (11) at the bottom with internal threads; and a shelf (12) fixed above the support column (11). 7.The miniaturized integrated water acoustic detection system based on Φ-OTDR according to claim 6, characterized in that: The layer plate (12) is made of superconducting material to form an electromagnetically shielded lower optical cabin and an upper electronic cabin; the lower optical cabin is equipped with an adaptive optics platform that can adjust the position of optical devices in real time; the upper electronic cabin adopts a modular plug-in design, and each functional module is connected without solder joints through quantum dot conductive adhesive. 8.The Φ-OTDR-based small integrated underwater acoustic detection system according to claim 7, characterized in that, The optical compartment is equipped with a heat-conducting pad to cover the optical components and transfer heat to the housing (2) for heat dissipation; the electronic compartment is equipped with a heat-conducting pad to cover the electronic components and transfer heat to the cover plate (1) and the shelf plate (12) for heat dissipation.

9. The small integrated underwater acoustic detection system based on Φ-OTDR according to any one of claims 1-8, characterized in that, The adoption of new energy power supply solutions includes: The shell surface integrates a flexible solar film and a water flow energy harvesting device; The internal intelligent energy management module automatically optimizes energy distribution.

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