Metastructure for enhancing the detection sensitivity of underwater sound sensors and device including the same

Abstract

The present invention relates to a metastructure for improving the reception sensitivity of an underwater acoustic sensor and a device including the same, comprising: an acoustic incident plate having an incident surface formed on one side through which acoustic is incident; and a block-shaped metabody having one side in contact with the other side of the acoustic incident plate to improve the signal-to-noise ratio of the acoustic passing through the acoustic incident plate, wherein the metabody includes grooves formed on both sides facing a second axis direction perpendicular to a first axis direction through which acoustic passes, and a hole penetrating the center in a third axis direction perpendicular to the first and second axes, wherein the grooves and holes are formed in a plurality at a predetermined interval in the first axis direction.

Description

Technology Field

[0001] The present invention relates to a metastructure for improving the reception sensitivity of a sensor for measuring acoustics underwater and a device including the same. Background Technology

[0003] Underwater acoustic sensors are devices that detect and analyze acoustic signals in the marine environment. They are used for military and security purposes, such as submarine detection using SONAR systems and seabed topography exploration; for marine exploration, such as detecting seabed earthquakes, analyzing the sounds of marine life, and exploring seabed topography and resources; and for environmental monitoring, such as Underwater Acoustic Communication (UAC) systems, marine pollution detection, and marine ecosystem research.

[0004] Underwater acoustic sensors have a structure that detects acoustic signals transmitted underwater and converts them into electrical signals, and piezoelectric sensors, electromagnetic sensors, and optical sensors can be primarily used.

[0005] However, existing sensors have limitations in detecting minute signals and suffer from high costs and low durability. In particular, regarding signal processing, even when using low-noise amplifiers, environmental noise is amplified along with the signal, resulting in a low signal-to-noise ratio (SNR).

[0006] The aforementioned background technology is technical information that the inventor possessed or acquired during the process of deriving the embodiments of the present invention, and it cannot be considered as prior art disclosed to the general public prior to the filing of the embodiments of the present invention. The problem to be solved

[0008] To solve the above problem, the present invention provides a metastructure having a predetermined shape and a device including the same to improve the reception sensitivity of an underwater acoustic sensor. means of solving the problem

[0010] A metastructure for improving the reception sensitivity of an underwater acoustic sensor according to one embodiment of the present invention comprises: an acoustic incident plate having an incident surface formed on one side through which acoustic is incident; and a block-shaped metabody having one side in contact with the other side of the acoustic incident plate to improve the signal-to-noise ratio of the acoustic passing through the acoustic incident plate, wherein the metabody includes grooves formed on both sides facing a second axis direction perpendicular to a first axis direction through which acoustic passes, and a hole penetrating the center in a third axis direction perpendicular to the first axis and the second axis, and a plurality of grooves and holes may be formed with a predetermined spacing in the first axis direction.

[0011] According to one embodiment of the present invention, the grooves and holes may be arranged alternately in the first axis direction.

[0012] According to one embodiment of the present invention, the grooves may be formed parallel to each other in the third axis direction on both sides of the metabody.

[0013] According to one embodiment of the present invention, a plurality of meta bodies may be formed with a predetermined spacing in the second axis direction.

[0014] According to one embodiment of the present invention, the other surfaces of a plurality of meta bodies can be connected.

[0015] According to one embodiment of the present invention, the metabody may be formed of a thermoplastic polymer material.

[0016] According to one embodiment of the present invention, the thermoplastic polymer material may be ABS (Acrylonitrile Butadiene Styrene).

[0017] An apparatus for improving the reception sensitivity of an underwater acoustic sensor according to one embodiment of the present invention may include: a metastructure according to the present invention; and a medium portion having one surface in contact with the other surface of the metastructure and the other surface in contact with the acoustic inlet of the underwater acoustic sensor, and containing a predetermined medium inside to amplify the sound passing through the metastructure.

[0018] According to one embodiment of the present invention, the distance from one surface of the medium to the other surface may be Equation 1.

[0019] [Mathematical Formula 1]

[0020]

[0021] Here, d is the distance from one side of the medium to the other side, represents the wavelength of the sound at the target frequency to be received, and n represents an odd integer.

[0022] According to one embodiment of the present invention, a frame portion surrounding the outer periphery of an acoustic incidence plate of a metastructure may be further included to form an opening into which sound is incident.

[0023] According to one embodiment of the present invention, a converter may further include a converter that receives sound passing through a metastructure and a medium with an underwater acoustic sensor and converts the acoustic signal into a Fourier transform frequency. Effects of the invention

[0025] A metastructure for improving the reception sensitivity of an underwater acoustic sensor and a device including the same according to one embodiment of the present invention have the advantage of being able to improve the signal-to-noise ratio with only a simple configuration, without existing complex measurement systems or special programs.

[0026] In addition, since the device of the present invention can be mounted on the receiver of an existing underwater acoustic sensor, there is no need to replace the existing device.

[0027] In addition, since the meta structure of the present invention can be manufactured through 3D printing, it is easy to manufacture and repair.

[0028] The effects obtainable from the invention are not limited to those mentioned above, and other unmentioned effects will be clearly understood by those skilled in the art to which the invention belongs from the description below. Brief explanation of the drawing

[0030] FIGS. 1 and 2 illustrate a perspective view, a front view, a top view, and a side view of a metastructure for improving the reception sensitivity of an underwater acoustic sensor according to one embodiment of the present invention. FIG. 3 shows a perspective view of a device including a metastructure for improving the reception sensitivity of an underwater acoustic sensor according to one embodiment of the present invention. FIG. 4 illustrates the results of a numerical analysis simulation of a device including a metastructure for improving the reception sensitivity of an underwater acoustic sensor according to one embodiment of the present invention. FIGS. 5 and 6 are graphs illustrating the simulation results of a received signal received by a device including a metastructure for improving the reception sensitivity of an underwater acoustic sensor according to one embodiment of the present invention and a received signal according to a comparison example. Specific details for implementing the invention

[0031] The present invention will become clear from the embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below but may be implemented in various different forms. These embodiments are provided merely to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention, and the present invention is defined only by the scope of the claims. Meanwhile, the terms used in this specification are for describing the embodiments and are not intended to limit the present invention.

[0032] Throughout this specification, the singular form includes the plural form unless specifically stated otherwise in the text.

[0033] Throughout this specification, the terms “comprises” and / or “comprising” as used mean that the mentioned components, steps, actions and / or elements do not exclude the presence or addition of one or more other components, steps, actions and / or elements, and that, unless specifically stated otherwise, they do not exclude other components but may include additional components.

[0034] Additionally, terms such as “...part” as used throughout this specification refer to a unit that processes at least one function or operation, which may be implemented in hardware or software, or a combination of hardware and software.

[0035] Furthermore, throughout this specification, when a part is described as being “connected” to another part, this includes not only cases where they are “directly connected” but also cases where they are connected “with other components in between.”

[0037] The present invention will be described in more detail below.

[0038] FIGS. 1 and 2 illustrate a perspective view, a front view, a top view, and a side view of a metastructure (100) for improving the reception sensitivity of an underwater acoustic sensor according to one embodiment of the present invention.

[0039] Referring to FIGS. 1 and 2, a meta structure (100) for improving the reception sensitivity of an underwater acoustic sensor according to one embodiment of the present invention may include an acoustic incident plate (110) and a meta body (120).

[0040] The acoustic incident plate (110) is configured such that sound incident on one side can pass through to the other side, and is formed in contact with one side of the meta structure (100) described below. Here, the one side may be formed as an incident surface (111) that forms a predetermined area. The shape of the incident surface (111) is not particularly limited, but if a plurality of meta bodies (120) described below are formed, it may be provided with a shape opposite to the position and shape where the corresponding meta bodies (120) are provided.

[0041] The meta body (120) is configured to be stacked in the direction through which sound passes (hereinafter, in the first axis direction, in the x-axis direction of FIG. 1 and FIG. 2) to transmit sound incident on the acoustic incident plate (110).

[0042] More specifically, one side of the meta body (120) is in contact with the other side of the acoustic incident plate (110), and the configuration is a block shape formed by a meta structure (100) such that when sound passing through the acoustic incident plate (110) is incident on and passes through the meta body (120), the signal-to-noise ratio (SNR) of the sound passing through can be improved. The shape of the meta body (120) is described in detail below.

[0043] Referring to FIGS. 1 and 2, the metabody (120) has a shape having a volume with a plurality of faces formed therein, and grooves (121) may be formed on both sides facing the second axis direction (y-axis direction in FIGS. 1 and 2) which is perpendicular to the first axis direction. The shape and length of the grooves (121) are not particularly limited, but preferably, they may be formed in an uneven shape and may be formed parallel to the third axis direction (z-axis direction in FIGS. 1 and 2) which is perpendicular to the first axis and the second axis.

[0044] Additionally, the meta body (120) may include a hole (122) penetrating the center in the third axis direction. This may penetrate the meta body (120) in a direction parallel to the grooves (121) formed on both sides. The shape of the hole (122) is not particularly limited, but preferably, it may be provided penetrating the meta body (120) with a square cross-section.

[0045] These grooves (121) and holes (122) may be formed in multiple numbers in the first axis direction and spaced apart at a predetermined interval. Referring to FIGS. 1 and 2, it is preferable that the grooves (121) and holes (122) be arranged alternately in the first axis direction.

[0046] In addition, the meta body (120) may be provided in at least one or more ways in the meta structure (100) of the present invention. That is, a plurality of meta bodies (120) may be formed into a single meta structure (100).

[0047] Referring to FIGS. 1 and 2, a plurality of meta bodies (120) may be arranged in a second axis direction. In particular, the meta bodies (120) may be arranged spaced apart at a predetermined interval in the second axis direction. Preferably, the meta bodies (120) may be arranged spaced apart at a predetermined interval in the second axis direction. More preferably, the other sides of the plurality of meta bodies (120) may be formed to be in contact with each other, and the portion between one side and the other side of the meta bodies (120) may be formed spaced apart.

[0048] The dimensions and spacing of the groove (121) and hole (122) formed in the meta body (120) of the present invention, and the spacing between a plurality of meta bodies (120), are not particularly limited and can be modified according to the type of underwater acoustic sensor and the size of the device including the meta structure (100) of the present invention.

[0049] In the meta structure (100) of the present invention, the type of meta body (120) may be formed from a thermoplastic polymer material. Preferably, the thermoplastic polymer material may be ABS (Acrylonitrile Butadiene Styrene). When the meta body (120) is formed from ABS, it is easy to manufacture through 3D printing and can effectively improve the signal-to-noise ratio of the sound.

[0051] FIG. 3 shows a perspective view of a device (10) including a metastructure for improving the reception sensitivity of an underwater acoustic sensor according to one embodiment of the present invention.

[0052] Referring to FIG. 3, the device (10) of the present invention may include a meta structure (100) and a medium part (200) in contact with the meta structure (100).

[0053] The meta structure (100) may include all the features of the meta structure (100) for improving the reception sensitivity of an underwater acoustic sensor according to one embodiment of the present invention described above.

[0054] The medium section (200) is configured such that one side is in contact with the other side of the meta structure (100), and the other side is in contact with the acoustic inlet (s) of the underwater acoustic sensor. That is, the medium section (200) can be provided between the meta structure (100) and the underwater acoustic sensor. Accordingly, in the device (10) according to the present invention, the acoustic incident plate (110), the meta body (120), and the medium section (200) are stacked sequentially, and sound generated underwater can pass through in the above order and be introduced into the acoustic inlet (s) of the underwater acoustic sensor.

[0055] In particular, the medium portion (200) may include a medium for amplifying the magnitude of sound passing through, with a predetermined space formed inside. Here, the medium may be a liquid such as water or oil, as well as a uniform or non-uniform solid.

[0056] In particular, the distance from one side to the other side of the medium (200) can be formed by the following mathematical formula 1.

[0057] [Mathematical Formula 1]

[0058]

[0059] Here, d is the distance from one side to the other side of the medium part (200), is the wavelength of the sound at the target frequency to be received, n represents an odd integer.

[0060] Generally, the wavelength of sound in a medium ( Since ) is inversely proportional to the propagation speed (c) of sound entering the medium, the distance from one side to the other side of the medium part (200) can be reduced as a medium with a smaller propagation speed is used.

[0061] FIG. 4 illustrates the results of a numerical analysis simulation of a device (10) including a metastructure for improving the reception sensitivity of an underwater acoustic sensor according to an embodiment of the present invention. Referring to FIG. 4, the sound pressure passing through the metastructure (100) is formed with a somewhat low magnitude (yellow part), but the magnitude of the sound pressure can increase (red part) as it passes through the medium part (200). That is, the magnitude of the amplitude of the sound pressure signal can increase as it moves in the x-axis direction. In addition, the present invention has the advantage of being able to amplify the target frequency to be actually received while simultaneously suppressing surrounding frequencies (noise) relatively.

[0062] Also, referring to FIG. 3, a frame portion (300) surrounding the outer periphery of the acoustic incident plate (110) of the metastructure (100) may be further included to form an opening into which sound is incident. The frame portion (300) is intended to separate the area of ​​the part into which sound is incident from the acoustic incident plate (110), and in one embodiment, it may be provided as a frame made of steel.

[0064] The effects of the present invention are compared below through comparative examples and embodiments.

[0065] FIGS. 5 and 6 are graphs showing the simulation results of a received signal received by a device (10) including a metastructure for improving the reception sensitivity of an underwater acoustic sensor according to one embodiment of the present invention and a received signal according to a comparison example.

[0066] FIG. 5(a) is a graph of the results of a simulation of measuring sound received by a device (10) including the meta-structure of the present invention. It can be seen that the device (10) including the meta-structure of the present invention has a large relative size of the target frequency portion to be actually received, while the size of the noise is relatively low.

[0067] Figure 5(b) is a graph showing the results of a simulation of sound received by a general device. It can be seen that with a general device, the noise magnitude in the frequency portion is relatively large over time, so the target frequency portion to be actually received cannot be distinguished.

[0068] This can be distinguished more clearly when the received acoustic signal is Fourier transformed.

[0069] Referring to FIG. 6(a), in the results of a simulation in which sound received by a device (10) including the meta-structure of the present invention is measured, it can be seen that the target frequency portion to be actually received is more clearly different. On the other hand, in the results of a simulation in which sound received by a general device is measured, it can be seen that the target frequency portion to be actually received is not clearly distinguishable.

[0070] Accordingly, the device (10) including a metastructure for improving the reception sensitivity of an underwater acoustic sensor according to one embodiment of the present invention may further include a converter (not shown) that receives sound passing through the metastructure (100) and the medium part (200) with an underwater acoustic sensor and converts the acoustic signal into a Fourier transform frequency. The converter is not particularly limited as long as it is configured to perform a Fourier transform on the received acoustic signal, and in one embodiment, it may be a microprocessor.

[0072] Although the present invention has been described above by limited embodiments, the present invention is not limited thereto, and it is obvious that various modifications and variations are possible within the scope of the technical spirit of the present invention and the equivalent scope of the claims described below by those skilled in the art to which the present invention belongs. Explanation of the symbols

[0074] 10: Device including a metastructure 100: Metastructure 110: Acoustic incident plate 120: Meta body 121: Home 122: Hall 200: Medium part 300: Frame section

Claims

Claim 1 A metastructure for improving the reception sensitivity of an underwater acoustic sensor, comprising: an acoustic incident plate having an incident surface formed on one side through which acoustic is incident; and a block-shaped metabody having one side in contact with the other side of the acoustic incident plate to improve the signal-to-noise ratio of the acoustic passing through the acoustic incident plate, wherein the metabody includes grooves formed on both sides facing a second axis direction perpendicular to a first axis direction through which acoustic passes, and a hole penetrating the center in a third axis direction perpendicular to the first and second axes, wherein the grooves and holes are formed in a plurality at a predetermined interval in the first axis direction. Claim 2 A meta structure according to claim 1, characterized in that the grooves and holes are arranged alternately in the first axis direction. Claim 3 A meta structure according to claim 1, wherein the groove is formed parallel to the third axis direction on both sides of the meta body. Claim 4 A meta structure according to claim 1, wherein the meta body is formed in a plurality of portions spaced apart at a predetermined interval in the direction of the second axis. Claim 5 In paragraph 4, the meta structure is characterized in that the other surfaces of a plurality of the above meta bodies are connected. Claim 6 In claim 1, the meta-body is characterized by being formed of a thermoplastic polymer material. Claim 7 A meta-structure characterized in that, in claim 6, the thermoplastic polymer material is ABS (Acrylonitrile Butadiene Styrene). Claim 8 A device for improving the reception sensitivity of an underwater acoustic sensor, comprising: a metastructure according to any one of claims 1 to 7; and a medium part having one surface in contact with the other surface of the metastructure and the other surface in contact with the acoustic inlet of the underwater acoustic sensor, and containing a predetermined medium inside to amplify the sound passing through the metastructure. Claim 9 An apparatus according to claim 8, characterized in that the distance from one side to the other side of the medium is Equation 1.[Equation 1] Here, d is the distance from one side to the other side of the medium, represents the wavelength of the sound at the target frequency to be received, and n represents an odd integer. Claim 10 In claim 8, the device further comprises a frame portion surrounding the outer periphery of the acoustic incidence plate of the metastructure to form an opening into which sound is incident. Claim 11 The apparatus according to claim 8, further comprising a converter that receives sound passing through the metastructure and medium portion with an underwater acoustic sensor and converts the acoustic signal into a Fourier transform frequency.

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