CN116430315A - Sound source single-point positioning device and method, electronic equipment and storage medium - Google Patents
Sound source single-point positioning device and method, electronic equipment and storage medium Download PDFInfo
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S5/00—Position-fixing by co-ordinating two or more direction or position line determinations; Position-fixing by co-ordinating two or more distance determinations
- G01S5/18—Position-fixing by co-ordinating two or more direction or position line determinations; Position-fixing by co-ordinating two or more distance determinations using ultrasonic, sonic, or infrasonic waves
- G01S5/22—Position of source determined by co-ordinating a plurality of position lines defined by path-difference measurements
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01H—MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
- G01H9/00—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by using radiation-sensitive means, e.g. optical means
- G01H9/004—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by using radiation-sensitive means, e.g. optical means using fibre optic sensors
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P40/00—Technologies relating to the processing of minerals
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Abstract
The present disclosure relates to a sound source single point positioning device and method, an electronic device, and a storage medium, the device comprising: the micro-nano optical fiber sensing component, the acoustic wave coupling tube and the signal processing component; the length of the acoustic wave coupling tube is smaller than the acoustic wave length; the micro-nano optical fiber sensing assembly comprises acoustic films and micro-nano optical fibers, wherein the acoustic films are packaged at two ends of the acoustic wave coupling tube, the micro-nano optical fibers are distributed on the acoustic films, and the micro-nano optical fibers are used for transmitting a first optical signal, a second optical signal, a third optical signal and a fourth optical signal respectively; the signal processing component is connected with the micro-nano optical fiber, performs photoelectric conversion on an optical signal received from the micro-nano optical fiber, correspondingly generates a first photoelectric signal, a second photoelectric signal, a third photoelectric signal and a fourth photoelectric signal, restores sound waves generated by a sound source to be positioned by using the first photoelectric signal and the second photoelectric signal, and performs single-point positioning on the sound source to be positioned by using the third photoelectric signal and the fourth photoelectric signal. The embodiment of the disclosure can realize single-point accurate positioning of the sound source and high-fidelity recovery of the sound source information when the sensor spacing is smaller than the sound wave wavelength.
Description
Technical Field
The invention relates to the field of sound wave positioning detection, in particular to a sound source single-point positioning method and device.
Background
In recent years, acoustic detection and acoustic localization techniques have played an important role in the fields of industry, traffic, military, and the like. The most commonly used device in sound source positioning is a microphone array, the array type microphone utilizes the time delay difference of sound signals reaching each microphone and the geometric relation between each microphone to solve the sound source position, and because of the limitation of the wavelength of a target sound source, the adjacent array elements in the microphone array are required to keep a larger distance to generate detectable time delay difference, and the limitation is larger, so that the research of the miniaturized sound positioning technology and devices with wide application range is carried out, and the device has important application value.
The optical microphone is an acoustic wave measurement technology for inverting sound source information by detecting mechanical movement of a cantilever or a reflecting film induced by acoustic waves in an acoustic wave monitoring system, and compared with a traditional acoustic microphone, the optical microphone can accurately capture vibration of a sound source part, isolate the vibration from background noise and convert the vibration into a light intensity signal for transmission, so that the acoustic microphone has better anti-noise performance. In addition, when the traditional acoustic microphone receives sounds with different frequencies, the output signal can be amplified or attenuated along with the change of the frequencies, and the defect of the traditional acoustic microphone is overcome by the appearance of the optical microphone, and the optical microphone has higher sensitivity and larger detection frequency range due to the adoption of the optical signal as a conducting medium.
In the existing optical microphone measurement technology, as shown in CN114449426a publication, a membraneless optical microphone is represented, wherein sound pressure waves are detected by pure optics of a micro fabry-perot etalon. The etalon is a small interference cavity formed by two parallel semi-transparent mirrors with millimeter size, works by sensing the tiny change of the refractive index of a sound propagation medium of the cavity, can realize analysis of sound wave signals, but can not realize single-point positioning of a sound source. In summary, in the prior art, single-point positioning of a sound source cannot be achieved by using an optical microphone, and there is also a strict limitation on the distance between sensors in sound wave detection and sound source positioning.
Disclosure of Invention
The disclosure provides a single-point positioning method and device for a sound source, and the method and device can solve the problem that sound source positioning is difficult to achieve when the sound wave wavelength is larger than the sensor spacing.
According to an aspect of the present disclosure, there is provided a sound source single point localization apparatus including: the micro-nano optical fiber sensing component, the acoustic wave coupling tube and the signal processing component; the length of the acoustic wave coupling tube is smaller than the acoustic wave length.
The micro-nano optical fiber sensing assembly comprises acoustic films and micro-nano optical fibers, wherein the acoustic films are packaged at two ends of the acoustic wave coupling tube, the micro-nano optical fibers are distributed on the acoustic films, and the micro-nano optical fibers are respectively used for generating and transmitting a first optical signal, a second optical signal, a third optical signal and a fourth optical signal; the first optical signal and the second optical signal are optical signals generated by driving the micro-nano optical fiber to vibrate when acoustic films on two sides of the acoustic coupling tube are subjected to the initial action of acoustic waves of a sound source to be positioned, and the third optical signal and the fourth optical signal are optical signals generated by displacing the acoustic films on two sides again under the coupling action of the cavity of the acoustic coupling tube after a certain time interval;
the signal processing component is connected with the micro-nano optical fiber, performs photoelectric conversion on the optical signals received from the micro-nano optical fiber, correspondingly generates a first photoelectric signal, a second photoelectric signal, a third photoelectric signal and a fourth photoelectric signal, restores sound waves generated by a sound source to be positioned by using the first photoelectric signal and the second photoelectric signal, and realizes single-point positioning of the sound source by using the third photoelectric signal and the fourth photoelectric signal.
In some possible embodiments, the micro-nano optical fibers are distributed in a wavy shape extending from one end edge of the acoustic membrane to the opposite edge in a radial bend. Further, the micro-nano optical fiber adopts an embedded structure on the acoustic membrane to improve the sensitivity of sensing the vibration of the acoustic membrane.
In some possible embodiments, the preparation method of the micro-nano optical fiber comprises the following steps:
cutting two sections of single-mode optical fibers, and stripping a part of coating layer in the middle of the single-mode optical fibers;
wiping the residual coating layer on the single-mode optical fiber to obtain a preform for preparing the micro-nano optical fiber;
the step of stretching the preform rod by adopting a stepping motor and a micro-nano motion platform is as follows;
1) One end of the prefabricated rod is fixed on a micro-nano motion platform, the other end of the prefabricated rod is fixed on a stepping motor, the initial position of the stepping motor is set at 50mm, the speed is 100mm/s, and the acceleration is 0.3m/s 2 Deceleration of 0.2m/s 2 Heating and stretching the preform rod by adopting an alcohol lamp;
2) When the stepping motor moves to 46mm, the speed of the stepping motor is set to be 2mm/s and the acceleration is set to be 0.3m/s 2 Deceleration of 0.3m/s 2 Further stretching the optical fiber;
3) When the stepper motor moves to 22mm, the speed of the stepper motor is set to be 0.01mm/s and the acceleration is set to be 0.01m/s 2 Deceleration of 0.3m/s 2 Drawing the optical fiber is completed; the final fiber diameter was 1.5 μm, forming the micro-nano fiber.
In some possible embodiments, the apparatus further comprises: a light emitting assembly for generating an initial light signal;
the optical branching component is used for dividing the initial optical signal sent by the optical emission component into two paths and respectively transmitting the two paths of the initial optical signal to the initial optical signal input ends of the micro-nano optical fibers distributed on the acoustic films at the two ends of the acoustic coupling tube;
and/or
The signal processing assembly includes:
the two groups of photoelectric detectors are respectively connected with the optical signal output ends of the micro-nano optical fibers and are used for receiving a first optical signal, a second optical signal, a third optical signal and a fourth optical signal, and performing photoelectric conversion on the received optical signals to obtain the first photoelectric signal, the second photoelectric signal, the third photoelectric signal and the fourth photoelectric signal; one group of photoelectric detectors is used for receiving the first photoelectric signal and the third photoelectric signal, and the other group of photoelectric detectors is used for receiving the second photoelectric signal and the fourth photoelectric signal;
and the signal processor is connected with the photoelectric detector, performs differential noise reduction based on the characteristic that the phases of the received vibration signals between the first photoelectric signal and the second photoelectric signal are opposite, recovers the sound wave of the sound source to be positioned with high fidelity, and positions the sound source of the sound wave based on the phase difference, the time difference and the distance between the received third photoelectric signal and the received fourth photoelectric signal.
The signal processor is configured to perform differential noise reduction based on the characteristic that the phases of vibration signals between the first photoelectric signal and the second photoelectric signal are opposite, and restore sound waves of a sound source to be positioned with high fidelity;
the azimuth angle and the distance of the sound source to be positioned can be determined based on the phase difference and the time difference between the third photoelectric signal and the fourth photoelectric signal, and the two-dimensional position of the sound source to be positioned is determined according to the azimuth angle and the distance.
According to a second aspect of the present disclosure, there is provided a sound source localization method including: receiving four paths of optical signals transmitted by the micro-nano optical fiber sensing assembly; performing photoelectric conversion on the optical signals to obtain a first photoelectric signal, a second photoelectric signal, a third photoelectric signal and a fourth photoelectric signal; restoring sound waves of a sound source to be positioned by using the first photoelectric signal and the second photoelectric signal, determining azimuth angles and distances of the sound source to be positioned by using phase differences and time differences between a third photoelectric signal and a fourth photoelectric signal, and determining two-dimensional positions of the sound source to be positioned according to the azimuth angles and the distances;
the micro-nano optical fiber sensing assemblies are packaged at two ends of the acoustic wave coupling tube and comprise acoustic films packaged at two ends of the acoustic wave coupling tube and micro-nano optical fibers distributed on the acoustic films, wherein the micro-nano optical fibers are used for transmitting a first photoelectric signal, a second photoelectric signal, a third photoelectric signal and a fourth photoelectric signal respectively;
The first optical signal and the second optical signal are optical signals generated by driving the micro-nano optical fiber to vibrate by the sound films at two sides of the sound wave coupling tube under the action of sound waves of an external sound source, and are respectively recorded as a first optical signal and a second optical signal; when the acoustic films are subjected to external sound waves, a pressure is generated to opposite sides due to the coupling action of the sound wave coupling tube cavity, the sound films at the two sides are displaced again under the action of opposite sides pressure, and at the moment, the output light signals in the micro-nano optical fibers at the two sides of the sound wave coupling tube are respectively recorded as a third light signal and a fourth light signal.
According to a third aspect of the present disclosure, there is provided an electronic device comprising: a processor; a memory for storing processor-executable instructions; wherein the processor is configured to invoke the instructions stored in the memory to perform the sound source localization method of the second aspect; and/or comprising a sound source localization device as claimed in any one of the first aspects.
According to a fourth aspect of the present disclosure, there is provided a computer readable storage medium having stored thereon computer program instructions which, when executed by a processor, implement the method of the second aspect.
In the embodiment of the disclosure, in order to solve the technical problems mentioned in the background art, a technical scheme capable of realizing sound source detection and single-point positioning when the distance between the sensors is smaller than the wavelength of sound waves is provided. The sound source positioning device comprises a sound wave coupling tube and a micro-nano optical fiber sensing assembly packaged on the sound wave coupling tube, the sound films on two sides vibrate in the tube when the sound pressure is received by the sound films on two sides, the micro-nano optical fiber on the film is driven to vibrate, the phases of a first photoelectric signal and a second photoelectric signal which are output by the micro-nano optical fibers on two ends are opposite due to the opposite vibration directions of the sound films on two sides, and the high-fidelity recovery of sound source information can be realized by carrying out differential noise reduction on the first photoelectric signal and the second photoelectric signal. In addition, vibration on two sides of the acoustic membrane can be transmitted to opposite sides through the coupling cavity, at the moment, third photoelectric signals and fourth photoelectric signals received in the micro-nano optical fibers at two ends are transmitted, because the length of the acoustic coupling tube is smaller than the wavelength of acoustic waves, when the acoustic source emits acoustic signals, the two optical fibers can generate coupling in the cavity due to the pressure of the opposite side acoustic membrane, so that strong angular response is generated on incident acoustic waves, the ratio of the amplitudes of the two resonant cavities provides a clear method for determining the incident angle, the angular response is the result of coherent superposition of an ultra-radiation mode and a sub-radiation mode, due to the characteristic of degenerate modes in the micro-nano optical fibers, evanescent fields around the micro-nano optical fibers close to one side of the acoustic source are coupled to the other side, so that the output light intensity of the two sides is inconsistent, in addition, the coupling can amplify time difference between the two paths of signals, and further acoustic wave detection and acoustic source positioning can be realized by detecting the time difference of the two micro-nano optical fibers.
The method can detect the sound wave signal and locate the sound source with high sensitivity and high fidelity, can realize single-point location of the sound wave and improve the recovery quality of the sound wave signal.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure.
Other features and aspects of the present disclosure will become apparent from the following detailed description of exemplary embodiments, which proceeds with reference to the accompanying drawings.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the disclosure and together with the description, serve to explain the technical aspects of the disclosure.
Fig. 1 illustrates a schematic structural diagram of a sound source localization apparatus according to an embodiment of the present disclosure;
FIG. 2 shows a schematic structural diagram of a sound source localization device according to an embodiment of the present disclosure;
FIG. 3 illustrates a schematic view of spatial coordinates and azimuth angles in accordance with an embodiment of the present disclosure;
FIG. 4 is a flow chart of a sound source localization method of an embodiment of the present disclosure;
FIG. 5 is a schematic diagram of a structure simulating acoustic membrane movement in accordance with an embodiment of the present disclosure;
Detailed Description
Various exemplary embodiments, features and aspects of the disclosure will be described in detail below with reference to the drawings. In the drawings, like reference numbers indicate identical or functionally similar elements. Although various aspects of the embodiments are illustrated in the accompanying drawings, the drawings are not necessarily drawn to scale unless specifically indicated.
The word "exemplary" is used herein to mean "serving as an example, embodiment, or illustration. Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments.
The term "and/or" is herein merely an association relationship describing an associated object, meaning that there may be three relationships, e.g., a and/or B, may represent: a exists alone, A and B exist together, and B exists alone. In addition, the term "at least one" herein means any one of a plurality or any combination of at least two of a plurality, for example, including at least one of A, B, C, and may mean including any one or more elements selected from the group consisting of A, B and C.
Furthermore, numerous specific details are set forth in the following detailed description in order to provide a better understanding of the present disclosure. It will be understood by those skilled in the art that the present disclosure may be practiced without some of these specific details. In some instances, methods, means, elements, and circuits well known to those skilled in the art have not been described in detail in order not to obscure the present disclosure.
The sound source positioning device provided by the embodiment of the disclosure can be used for single-point positioning of sound sources of sound waves and can be used in optical microphones. Fig. 1 is a schematic block diagram of a sound source positioning device according to an embodiment of the present disclosure, fig. 2 is a schematic block diagram of a sound source positioning device according to an embodiment of the present disclosure, and fig. 3 is a schematic diagram of space coordinates and azimuth angles according to an embodiment of the present disclosure. Wherein, sound source positioning device includes: the micro-nano optical fiber sensing assembly 10, the acoustic wave coupling tube 20 and the signal processing assembly 30.
The acoustic coupling tube 20 may be configured as a tubular structure having a cavity, such as a cylindrical tube. The micro-nano optical fiber sensing assembly 10 is packaged at two ends of the acoustic wave coupling tube 20 to form a closed acoustic wave sensing assembly. The micro-nano optical fiber sensing assembly 10 may include an acoustic membrane 11 disposed at two ends of the acoustic coupling tube 10, and a micro-nano optical fiber 12 disposed on the acoustic membrane. In the embodiment of the disclosure, the length of the acoustic wave coupling tube is smaller than the acoustic wave length; the micro-nano optical fibers 12 on the acoustic membrane on both sides are used for generating and transmitting a first optical signal, a second optical signal, a third optical signal and a fourth optical signal respectively. The signal processing assembly 30 is connected to the micro-nano optical fiber assembly 10, performs photoelectric conversion on the optical signal received from the micro-nano optical fiber assembly 10, correspondingly generates a first photoelectric signal, a second photoelectric signal, a third photoelectric signal and a fourth photoelectric signal, and locates the sound source of the sound wave by using the four photoelectric signals.
The light emitting assembly of the embodiments of the present disclosure may include a laser 41 and a coupler 42. The laser 41 may be a distributed feedback laser with an output wavelength λ=1550 nm and an output power of 2.35 mW. The laser 41 is configured to generate and emit an initial optical signal, which may be split into two optical signals, a first optical signal and a second optical signal, via the coupler 42. Wherein the coupler 42 may be a 1×2 coupler configured with a wavelength of 1550nm, a bandwidth of ±15nm, a splitting ratio of 50:50, and an interface type of FC/PC connector. And transmitted to the micro-nano optical fiber of the micro-nano optical fiber sensing assembly via the coupler 42.
In some possible implementations, the two micro-nano optical fibers 11 of the examples of the present disclosure are micro-nano optical fibers made of single-mode optical fibers having a diameter of 1.5 μm and a length of 1.5cm of thin optical fiber lines.
The method for preparing the micro-nano optical fiber comprises the following steps:
cutting two sections of single-mode optical fibers, and stripping a part of coating layer in the middle of the single-mode optical fibers; wiping the residual coating layer on the single-mode optical fiber to obtain a preform for preparing the micro-nano optical fiber; and (3) scanning and heating the preform rod back and forth to a molten state by flame, and then stretching, wherein the diameter of a molten part is continuously reduced in the stretching process, so that the micro-nano optical fiber is formed.
The specific steps for preparing micro-nano optical fibers may be as follows, but are not specifically defined by the present disclosure.
The step of stretching the preform rod by adopting a stepping motor and a micro-nano motion platform is as follows;
1. one end of the prefabricated rod is fixed on a micro-nano motion platform, the other end of the prefabricated rod is fixed on a stepping motor, the initial position of the stepping motor is set at 50mm, the speed is 100mm/s, and the acceleration is 0.3m/s 2 Deceleration of 0.2m/s 2 Heating and stretching the preform rod by adopting an alcohol lamp;
2. when the stepping motor moves to 46mm, the speed of the stepping motor is set to be 2mm/s and the acceleration is set to be 0.3m/s 2 Deceleration of 0.3m/s 2 Further stretching the optical fiber;
3. when the stepper motor moves to 22mm, the speed of the stepper motor is set to be 0.01mm/s and the acceleration is set to be 0.01m/s 2 Deceleration of 0.3m/s 2 Drawing the optical fiber is completed; the final fiber diameter was 1.5 μm, forming the micro-nano fiber.
In the disclosed embodiment, the acoustic wave coupling tube 20 is configured as a pipe structure having a cavity, such as may be configured as a glass tube. In one embodiment, the acoustic coupling tube 20 may be a transparent quartz glass tube, specifically a silica capillary tube 1.6cm in height, 1cm in bottom diameter, and 1mm in wall thickness.
In addition, the acoustic membrane 11 of the micro-nano optical fiber sensing assembly 10 may be a circular film packaged at two sides of the acoustic coupling tube 20, so that the acoustic coupling tube 20 is constructed into a closed tube cavity structure, and when the acoustic membrane vibrates, the internal air flow is affected by the vibration pressure to generate pressure coupling and interference on the opposite acoustic membrane, so that the vibration of the acoustic membranes at two sides generates a difference. The acoustic membrane of the embodiments of the present disclosure may be a circular thin film having a diameter of 1cm and a thickness of 200 μm, and the material may be Polydimethylsiloxane (PDMS).
In some possible embodiments, the method of making an acoustic membrane may comprise: 1) Firstly, fully stirring and mixing PDMS basic components and a curing agent respectively according to the mass ratio of 10:1, and then placing the mixed PDMS in a vacuum pump to pump out bubbles; 2) After the bubbles are removed, the mixed PDMS is evenly spread on a glass slide, the thickness of the PDMS is 200 mu m, and the glass slide is placed in an incubator at 80 ℃ for 1 hour for shaping; 3) The resulting PDMS was then cut into 1cm diameter discs.
After the acoustic membrane is prepared, it may be assembled with the micro-nano optical fiber 12 by a method comprising: spreading a layer of 100 mu m prepared PDMS adhesive on the cut PDMS wafer; and bending and distributing the drawn micro-nano optical fiber waist area on the PDMS, so that the micro-nano optical fiber 11 is completely wrapped by the acoustic membrane PDMS. Then placing the mixture into a constant temperature oven for baking. For the sonic frequency range of 20Hz-20000Hz, the transmission tube can be configured as a glass tube with a length of 1.6cm, a diameter of 1cm and a wall thickness of 1 mm. And then PDMS wrapping the micro-nano optical fiber can be fixed at two ends of the glass tube (the periphery is sealed by PDMS and then baked to form a closed cavity) to be used as an acoustic wave sensor.
In some possible embodiments, the micro-nano optical fibers 12 may be arranged on the acoustic membrane 11 in a wavy manner, or may also be distributed in a spiral loop extending from one end edge of the acoustic membrane 11 to the opposite edge in a curved manner. The micro-nano optical fibers 12 can be more sensitive to the vibration of the acoustic membrane 11 through bending distribution, and the difference of photoelectric signals detected by the micro-nano optical fibers on the acoustic membranes on the two sides can be further increased due to the vibration difference of the acoustic membranes on the two sides, so that the sensitivity and the accuracy of the sensor are improved. In addition, in the embodiment of the present disclosure, the micro-nano optical fibers 12 on the acoustic films at two sides are symmetrically distributed, so as to keep the same arrangement mode at two sides, so as to improve the stability and measurement accuracy of the sensor.
In some possible implementations, the signal processing assembly 30 of the disclosed embodiments may include a photodetector 31 and a signal processor 32. The optical fiber may include two photodetectors 31, and the two photodetectors 31 may be respectively connected to the micro-nano optical fiber 12, and perform photoelectric conversion on the received first optical signal, second optical signal, third optical signal, and fourth optical signal to obtain a first optical signal, the second optical signal, the third optical signal, and the fourth optical signal. The signal processor 32 is connected to the photodetector 31, and recovers an acoustic signal based on a phase difference between the received first and second photoelectric signals, and uses a phase difference and a time difference between the third and fourth photoelectric signals to realize single-point positioning of a sound source.
In the embodiment of the disclosure, the photodetector 31 may be configured as an invisible light type photodetector, manufactured by the company of cable Lei Bo, and the model number is DET01CFC, which is matched with the distributed feedback laser, and the detection range of the invisible light type photodetector is 800nm-1700nm, and is used in combination with the laser, so as to detect the first photoelectric signal, the second photoelectric signal, the third photoelectric signal and the fourth photoelectric signal. When the acoustic films on two sides of the acoustic coupling tube are subjected to the acoustic action of an external acoustic source, a first optical signal and a second optical signal are generated in the micro-nano optical fibers on two sides of the acoustic coupling tube, and then the first optical signal and the second optical signal are detected by the photoelectric detectors on two sides of the acoustic coupling tube, and when the acoustic films on two sides are displaced again due to the coupling action of the acoustic coupling tube cavity, compared with the first optical signal and the second optical signal, the amplitude and the frequency of the signals detected by the photoelectric detectors are changed at the moment, so that the first optical signal, the second optical signal, the third optical signal and the fourth optical signal are distinguished.
In some embodiments of the present disclosure, the signal processor 32 may incorporate a multi-channel USB dynamic signal acquisition module 33 for sampling the photoelectric signal, converting the analog signal into a digital signal, and then analyzing the digital signal to locate the light source. In the application process, the space positions and optical fibers of a laser, a 1X 2 coupler, a micro-nano optical fiber, an acoustic membrane, a transparent glass tube, a photoelectric detector and a signal processing component are fixed. After fixing, the optical path is required to be ensured to be communicated, then the change of the light intensity signal caused by the micro-nano optical fiber is detected by utilizing the photoelectric detectors, and after the two photoelectric detectors detect the signals, the signal acquisition module converts the acquired first photoelectric signal, second photoelectric signal, third photoelectric signal and fourth photoelectric signal into digital signals and transmits the digital signals to the signal processor. The signal processor filters two paths of light intensity signals after digital signal conversion under the control of a pre-installed program, and the light intensity signals are detected by the photoelectric detectors at two ends to recover sound waves and perform single-point positioning on a sound source. Wherein, two paths of acquisition channels can be added firstly, and then the sampling frequency and the sampling point number are set; positioning two paths of digital signals obtained in the second step as S1 and S2 respectively, inputting the two paths of signals into a low-pass filtering control, and recording output signals as S11 and S21; the detection and sound source localization of the sound wave signals can be realized by analyzing the two paths of signals.
In some possible embodiments, the signal processor 32 may recover sound source information based on the first and second photoelectric signals, and determine the azimuth of the sound wave using the phase difference and the time difference of the third and fourth photoelectric signals. For example, the phase difference and the time difference of the third photoelectric signal and the fourth photoelectric signal can be detected, and the distance of the sound source is determined according to the product of the receiving time difference of the two paths of signals and the speed of light, so that the single point positioning is carried out on the sound source on the horizontal plane where the sensor is located.
In other possible embodiments, the signal processor 32 may further determine an azimuth angle of the sound source according to a time difference between the third photoelectric signal and the fourth photoelectric signal, and localize a spatial position of the sound source according to the azimuth angle. In the embodiment of the present disclosure, a plane coordinate system may be established based on the center of the acoustic wave coupling tube 20, wherein a schematic diagram of the plane coordinate system of the embodiment of the present disclosure is shown in fig. 4. The center of the acoustic wave coupling tube 20 is taken as an origin o, the length direction of the acoustic wave coupling tube 20 is taken as an x-axis, the radial direction which is horizontally perpendicular to the x-axis is taken as a y-axis, and the angle of the acoustic source on the xoy plane is taken as an azimuth angle theta.
In some embodiments of the disclosure, the high-fidelity recovery is performed on the sound source according to the first photoelectric signal and the second photoelectric signal, and the azimuth angle and the distance of the sound source are determined according to the phase difference and the time difference of the third photoelectric signal and the fourth photoelectric signal. Comprising at least one of the following means:
a) And performing high-fidelity recovery on the information of the sound source signal by using the phase difference of the first photoelectric signal and the second photoelectric signal.
Wherein, the embodiment of the disclosure can lay sound sources around the sound source positioning device in advance through an experimental recording mode, record the position information of the sound sources, such as plane space coordinates, azimuth angle and distance, and vibrate through the acoustic films of the micro-nano optical fiber sensing assembly, when the acoustic films at two sides receive sound pressure, the acoustic films at two sides vibrate into the tube, the micro-nano optical fibers on the film are driven to vibrate, and as the vibration directions of the acoustic films at the two sides are opposite, the phases of the first photoelectric signals and the second photoelectric signals output by the micro-nano optical fibers at the two ends are opposite, namely, the phases of the first photoelectric signals and the second photoelectric signals output are opposite, and the high-fidelity recovery is carried out on the sound source signals by carrying out differential noise reduction on the first photoelectric signals and the second photoelectric signals.
B) The movement trend of the acoustic membrane after bending towards the inner side of the pipe wall is that the acoustic membranes at the two sides bend towards the outer side of the pipe wall. In the process, the sound membrane at one end of the near sound source is subjected to the coupling action of the sound membrane at one end of the far sound source, and the time difference between the sound membranes at the left end and the right end can be amplified in the process. The azimuth angle and the distance can be determined by utilizing the phase difference and the time difference of the third photoelectric signal and the fourth photoelectric signal, so that the single-point positioning of the sound source is realized.
In this embodiment, after the sound source emits sound, the sound films at two ends are subjected to external pressure from the sound waves so that the sound films at two ends are recessed inwards, and the first optical signal and the second optical signal can be used to perform high-fidelity recovery on the sound source signal, as shown in fig. 5, so as to simulate the movement process of the sound film, and when the sound film receives the external sound wave pressure of the sound source and is recessed towards the inner side of the pipe wall, the sound film is located at the position shown as 1 in the example. The bending direction of the acoustic membrane is opposite at this time. The light intensity signals detected by the micro-nano optical fiber in the acoustic membrane are as follows:
wherein I is 1 Representing the interference signal due to left-hand acoustic membrane vibration, I 2 Representing the interference signal generated by the vibration of the sound film on the right side, the two paths of interference signals are opposite in phase because the vibration directions of the sound film on the left side and the sound film on the right side are opposite, the following formula can be obtained by subtracting the formula (15) and the formula (16),
By subtracting the two paths of signals, the signal amplitude is doubled, the common mode noise of the signals is eliminated, and the signals are obtained by phase expansion
And then, the following formula is utilized to realize the high-fidelity recovery of the sound source signal.
In the embodiment of the disclosure, after the acoustic membrane is bent towards the inner side of the pipe wall, the acoustic membrane at the far sound source end is subjected to mode coupling of the acoustic membrane at the near sound source end, and the time difference that the sound source reaches the acoustic membranes at the two sides cannot be detected because the length of the acoustic coupling pipe is smaller than the wavelength of the sound wave. But when coupling is created in the cavity, the coupling causes the time difference of the sound source acting on the acoustic membrane to be amplified. The time difference of the sound source acting on the acoustic films at the two ends can be detected by utilizing the mode coupling process carried between the third photoelectric signal and the fourth photoelectric signal so as to obtain the azimuth angle and the distance. And localizes the spatial position of the sound source using azimuth and distance. And realizing single-point positioning of the sound source. The embodiment of the disclosure establishes the relationship between the space position and azimuth angle and distance of the sound source, and obtains the horizontal space position of the sound source based on the response time difference and the position corresponding relationship of the micro-nano optical fibers at two sides.
Based on the above configuration of the embodiments of the present disclosure, single-point localization of a sound source can be achieved. According to the embodiment of the disclosure, by constructing the acoustic cavity structure, acoustic wave detection and sound source single-point positioning can be realized at the sensor spacing under the subsonic wave wavelength, acoustic wave can be measured in real time, and the acoustic cavity structure has the advantages of low cost, good instantaneity, good applicability and the like. In addition, the bending micro-nano optical fiber is embedded in the sensing film, the light intensity signals with different amplitudes can be directly obtained by utilizing the high sensitivity of the micro-nano optical fiber and the coupling effect between the two micro-nano optical fibers, the recovery and the sound source positioning of the sound wave signals can be more conveniently realized, and the problem that the single point positioning cannot be realized due to the fact that the sound film distance of the traditional sound wave sensor is limited by the sound wave wavelength is solved. In addition, the present disclosure may be developed as an integrated device, miniaturizing the measurement apparatus, and applying to actual engineering measurement. Further, the present disclosure may utilize the linear relationship between the amplitude difference and the sound source angle within a sub-region of space to precisely localize the sound source position.
In addition, the embodiment of the present disclosure further provides a sound source positioning method, which may be used in an optical microphone or other acoustic wave device, and fig. 4 shows a flowchart of the sound source positioning method according to an embodiment of the present disclosure, where the method includes:
s100: receiving two paths of optical signals transmitted by the micro-nano optical fiber assembly;
s200: performing photoelectric conversion on the optical signals to obtain a first photoelectric signal, a second photoelectric signal, a third photoelectric signal and a fourth photoelectric signal;
s300: performing high-fidelity recovery on sound source information by using the first photoelectric signal and the second photoelectric signal, and performing single-point positioning on a sound source by using the third photoelectric signal and the fourth photoelectric signal;
the sound wave sensing assembly comprises a sound wave coupling tube and sound films arranged on two sides of the sound wave coupling tube cavity, and the length of the sound wave coupling tube cavity is smaller than the wavelength of sound waves; the micro-nano optical fiber assembly comprises two micro-nano optical fibers and is used for transmitting a first optical signal, a second optical signal, a third optical signal and a fourth optical signal, and the two micro-nano optical fibers are respectively packaged in acoustic films at two sides of the acoustic wave coupling tube cavity.
In order to support the principles of the methods and apparatus provided by the embodiments of the present disclosure, specific procedures and demonstrations of the embodiments of the present disclosure are described in detail below.
Referring to fig. 1 to 3, sensing films with micro-nano optical fibers embedded therein are packaged at both sides of a transparent glass tube.
The light intensity of the first and second optical signals output by the micro-nano optical fibers at two sides of the acoustic cavity can be respectively recorded as
Wherein I is 0 Representing the initial intensity of light in the micro-nano fiber,
L 1 (t 1 ) Representing displacement function L generated by sound pressure of sound source received by near-sound source micro-nano optical fiber 2 (t 2 ) Representing displacement function generated by far-sound source micro-nano optical fiber under the coupling of sound source sound pressure and air pressure in cavity, and the vibration directions of sound films at two sides are opposite, i.e. I is caused 1 And I 2 By subtracting the two paths of signals, differential noise cancellation of the sound source signal can be realized.
Let P be ex For an angular frequency w, the amplitude is |P ex Harmonic external pressure wave of. The sound source is located at an angle θ measured from the central axis of the head. Finger meansLet the pressure function at the tympanic membrane of the two acoustic membranes (x=0 and x=l) be
Wherein the wave number is
c is the speed of sound in air. P (P) ex0 、P exL The pressures of the two acoustic membranes x=0 and x=l are shown. θ is the angle (azimuth angle) between the sound source and the central axes of the two acoustic films, the range of θ is-180 DEG to 180 DEG, and w=2pi f is the angular frequency of the sound wave.
Let the air in the optical microphone cavity be moved by the described pressure p (x, r, phi; t), where p (x, r, phi; t) represents the forced pressure of the air in the cavity in a cylindrical coordinate system, r is the radius of the membrane, phi is the phase, and t is the time. At this time, the movement of the air in the chamber satisfies the following
Where c is the propagation velocity of the air in the cavity, assuming the air cavity is a closed cavity, if the air movement in the cavity is continuous in time, the average velocity v of the air movement in the cavity and the pressure p in the cavity satisfy the following equation, and the gradient change of the pressure is equal to the product of the air density ρ in the cavity and the derivative of the average velocity with time.
At this time, the movement velocity v of the particles in the air moving in the x direction x Can be written as follows
Wherein k is x In the x directionWavenumber, J q Bessel functions representing the q-th order of the first class, requiring adjustment of the coefficient k qs 、
And->
The vibration distribution of the internal air and the two films at x=0 and x=l was made the same.
Furthermore, since the cavity is closed, there is no mass transfer. The air cavity can be used as a whole resonant cavity, at the moment, when the membrane close to one side of the sound source vibrates due to sound pressure, air in the cavity is compressed to generate a pressure wave, the pressure wave can act on the sound membrane far away from one end of the sound source along with the forward transmission of the cavity, so that the net vibration of the sound membrane at the other side is reduced, the phase difference of optical signals in the micro-nano optical fibers in the sound membrane is enhanced by the coupling between the sound cavity and the membrane, and in addition, the output intensity of the optical signals of the micro-nano optical fibers in the membranes at two ends is different due to the existence of internal pressure waves.
The specific analysis process is as follows
When the two acoustic cavity films are subjected to external sound pressure P ex When the acoustic diaphragm vibration is the same as the micro-nano fiber vibration in the acoustic diaphragm, namely the displacement function of the two acoustic diaphragms is L x0 (t) and L xL (t). Wherein x is 0 The acoustic membrane of the near source is forced to vibrate mainly by the sound pressure from the source, while the driving force ψ (r, φ; t) of the far end acoustic membrane is the difference between the external pressure and the force exerted by the pulsating air in the lumen. In calculating the vibrational eigenmodes of the membrane, further consideration of the fiber-to-membrane loading is required. As previously described, the derivation is focused first on the force-driven membrane, and then the characteristic mode is calculated.
Let u (r, phi; t) be the displacement of one of the membranes in the x-direction. For u (r, phi; t) to satisfy the two-dimensional damped wave equation at polar coordinates under an applied force phi (r, phi; t)
Wherein alpha is the damping coefficient of the membrane, C M For the propagation speed of the wave on the film ρ m The film density, d the film thickness.
Where the film is fixed at the boundary r=a, i.e. u (a, phi; t) =0, the first step in solving (5) is to calculate the homogeneous solution (i.e. ψ=0), and it is possible to obtain
I.e. omega mn ＝k mn /C M Resonance frequency f at the time mn Is that
Wherein J m Representing a bessel function of order m. In addition, the boundary condition r=a also determines the parameter 
And->
The forces acting on the two acoustic membranes consist of two parts. On the one hand constant external pressure P from acoustic source stimulation ex On the other hand from the force of the oscillating air within the internal cavity. The external pressure is given by equation 1, the internal pressure is given by equation 4, and in general, the boundary conditions require that the velocity in the cylinder at x=0 and x=l be equal to the velocity of the diaphragm, as follows
The negative sign in the above ensures the displacement function mu of the membrane 0 Sum mu L Is consistent with the coordinate system of the cylinder. Function mu 0/L And v x Is a linear combination of orthogonal functions in the same set. Furthermore, only external forces from the sound source can activate the movement of the inner cavity. The pressure function P in the lumen can thus be written as:
in order to further characterize the relationship between the sound source position and the output time difference at the two ends of the micro-nano optical fiber, the central point of the central axis of the sound source measuring device is the origin of x and y coordinate axes, the x axis is the axial direction of the glass tube, and the y axis is the short axis direction of the glass tube. The cavity of the glass tube is closed, and acoustic films at two intersection points of edges of two sides of the device and the x axis in the model are used as vibration monitoring points. Because the scale of the sound source detection device is far smaller than the distance between the sound source and the sound film in the actual test, the far-field condition is satisfied. The sound wave can be approximated as a plane wave under far field conditions, so the sound field in this model is equivalent to a far-distance sound field, setting the sound source type as a plane wave.
The law of response at this frequency (when the sound wave frequency is incident at the eigenfrequency of the acoustic cavity membrane) as a function of the incident angle of the sound source is simulated based on the eigenfrequency of the coupling mode of the single-point localized fiber microphone. The plane sound wave is incident on the positioning device at an azimuth angle theta, and the incident sound wave can be expressed as
Where Pa is the amplitude of sound pressure of a sound source, ω=2ρc/λ, λ is the wavelength of sound waves, j is an imaginary unit, ω is the angular frequency of sound, t is time, c is the sound velocity in air, (x, y, z) is the coordinates of any point on a planar space with the center of a transmission tube as the center of a circle and 40cm as the radius.
According to the above-described derivation process, the direction of the sound source can be determined by comparing the differences in phase and time of the signals received by the two ears with the distance.
Assuming that the sound source has a direction angle θ (angle system) on the center line of the sensor, the length of the sensor is L 0 Then the sound source is located at a distance (L) from the left acoustic membrane of the sensor 0 D/2), a distance from the right ear of (L 0 +d/2), where d is the distance of the sound source from the lizard.
Let sound source emit sound wave with frequency f, sound velocity v, wavelength λ=v/f.
When the acoustic wave propagates to the left ear, it is reflected and scattered in the lizard head surface and structure, creating a phase difference 
When the sound wave propagates to the right ear, a phase difference is also generated>
These two phase differences can be expressed as:
wherein delta 1 And delta 2 The phase delay delta of the sound wave received by the left ear and the right ear respectively 1 And delta 2 Is small and can be ignored. Therefore, we can treat them as zero.
The phase difference of the signals received by the left and right acoustic membranes can be expressed as:
where j is an imaginary unit, pa is the amplitude of sound pressure of the sound source, ω=2ρc/λ, and λ is the wavelength of the sound wave.
Substituting the formula (13) and the formula (14) into the formula (15) to obtain
According to the nature of the trigonometric function, when the direction of the sound source deviates from the centerline of the sound transmission tube, the phase difference
A change occurs. Specifically, when the sound source moves to the left, the phase difference +.>
Will decrease; when the sound source moves to the right, the phase difference +.>
Will increase. The magnitude of this change is proportional to the angle of the sound source from the centerline of the sound tube. Thus, the direction θ of the sound source can be expressed as
Substituting the sound wave wavelength λ=v/f to obtain
In calculating the sound source distance, the sound source distance can be calculated by using the propagation speed of sound waves, the frequency of sound waves and the propagation time of sound waves in a medium, and the specific process is as follows
Assuming that the sound wave propagates in the air, the propagation speed of the sound wave in the air is about 340m/s, the frequency of the sound wave is f, and the propagation time of the sound wave in the air is t, the distance d from the sound source to the differential acoustic pipe can be expressed as:
d＝v×t＝340×f×t (18)
In order to measure the time when a sound wave arrives at the sound tube from the sound source, the time difference Δt of the sound wave received by both ears of the sound tube can be used, namely:
Δt＝t 2 -t 1 (19)
wherein t is 1 And t 2 The time of arrival of the sound waves at the left and right acoustic membranes of the sound tube, respectively. Since the propagation velocity of sound waves in air is known, the distance d of the sound source to the sound tube can be calculated from the propagation time difference of sound waves:
d＝v×Δt/2 (20)
where division by 2 is because the sound wave needs to travel back and forth, so only half the one-way time needs to be calculated. The distance d between the sound source and the transmission tube can be calculated, so that single-point positioning is realized.
Based on the above, the relationship between the azimuth angle and the time difference and the distance d between the sensor and the sound source can be obtained, and the single-point positioning of the sound source can be realized. In addition, in the detection process, when a sound source vibrates, the sensing film of the near sound source and the sensing film of the far sound source are influenced by external pressure to vibrate, but the sensing film of the far sound source and the sensing film of the near sound source generate coupling action through a cavity to reduce the net vibration of the sensing film of the far sound source, so that the light intensity of micro-nano optical fibers embedded in the sensing films at the two ends is different, and the light intensity detected at the near sound source end is larger than the light intensity detected at the far sound source end
It will be appreciated that the above-mentioned embodiments of the method and apparatus of the present disclosure may be combined with each other to form a combined embodiment without departing from the principle logic, which is not repeated herein for the sake of brevity.
It will be appreciated by those skilled in the art that in the above-described method of the specific embodiments, the written order of steps is not meant to imply a strict order of execution but rather should be construed according to the function and possibly inherent logic of the steps.
In some embodiments, functions or modules included in an apparatus provided by the embodiments of the present disclosure may be used to perform a method described in the foregoing method embodiments, and specific implementations thereof may refer to descriptions of the foregoing method embodiments, which are not repeated herein for brevity.
Claims (10)
1. A sound source single point positioning device, comprising: the micro-nano optical fiber sensing component, the acoustic wave coupling tube and the signal processing component; wherein, the liquid crystal display device comprises a liquid crystal display device,
the length of the acoustic wave coupling tube is smaller than the acoustic wave length;
the micro-nano optical fiber sensing assembly comprises acoustic films and micro-nano optical fibers, wherein the acoustic films are packaged at two ends of the acoustic wave coupling tube, the micro-nano optical fibers are distributed on the acoustic films, and the micro-nano optical fibers are respectively used for generating and transmitting a first optical signal, a second optical signal, a third optical signal and a fourth optical signal; the first optical signal and the second optical signal are optical signals generated by driving the micro-nano optical fiber to vibrate when acoustic films on two sides of the acoustic coupling tube are subjected to the initial action of acoustic waves of a sound source to be positioned, and the third optical signal and the fourth optical signal are optical signals generated by displacing the acoustic films on two sides again under the coupling action of the cavity of the acoustic coupling tube after a certain time interval;
The signal processing component is connected with the micro-nano optical fiber, performs photoelectric conversion on the optical signals received from the micro-nano optical fiber, correspondingly generates a first photoelectric signal, a second photoelectric signal, a third photoelectric signal and a fourth photoelectric signal, restores sound waves generated by a sound source to be positioned by using the first photoelectric signal and the second photoelectric signal, and realizes single-point positioning of the sound source by using the third photoelectric signal and the fourth photoelectric signal.
2. The device of claim 1, wherein the micro-nano fibers are distributed in a wavy curve extending radially from one end edge of the acoustic membrane to an opposite edge.
3. The device according to claim 1 or 2, wherein the preparation method of the micro-nano optical fiber comprises the following steps:
cutting two sections of single-mode optical fibers, and stripping a part of coating layer in the middle of the single-mode optical fibers;
wiping the residual coating layer on the single-mode optical fiber to obtain a preform for preparing the micro-nano optical fiber;
and (3) scanning and heating the preform rod back and forth to a molten state by flame, and then stretching, wherein the diameter of a molten part is continuously reduced in the stretching process, so that the micro-nano optical fiber is formed.
4. The apparatus of claim 3, wherein the method of preparing the micro-nano optical fiber comprises:
The flame of the preform rod is scanned and heated back and forth to a molten state by adopting a stepping motor and a micro-nano motion platform, and then the preform rod is stretched according to the following path;
one end of the preform rod is fixed on a micro-nano motion platform, the other end of the preform rod is fixed on a stepping motor, the initial position of the stepping motor is set at 50mm, the speed is 100mm/s, and the acceleration is 0.3m/s 2 Deceleration of 0.2m/s 2 Heating and stretching the preform rod by adopting an alcohol lamp;
when the stepping motor moves to 46mm, the speed of the stepping motor is set to be 2mm/s and the acceleration is set to be 0.3m/s 2 Deceleration of 0.3m/s 2 Further stretching the preform;
when the stepper motor moves to 22mm, the speed of the stepper motor is set to be 0.01mm/s and the acceleration is set to be 0.01m/s 2 Deceleration of 0.3m/s 2 And (3) stretching the preform, wherein the diameter of the preform is 1.5 mu m, and the micro-nano optical fiber is formed.
5. The apparatus according to any one of claims 1-4, further comprising:
a light emitting assembly for generating an initial light signal;
the optical branching component is used for dividing the initial optical signal sent by the optical emission component into two paths and respectively transmitting the two paths of the initial optical signal to the initial optical signal input ends of the micro-nano optical fibers distributed on the acoustic films at the two ends of the acoustic coupling tube;
And/or
The signal processing assembly includes:
the two groups of photoelectric detectors are respectively connected with the optical signal output ends of the micro-nano optical fibers and are used for receiving a first optical signal, a second optical signal, a third optical signal and a fourth optical signal, and performing photoelectric conversion on the received optical signals to obtain the first photoelectric signal, the second photoelectric signal, the third photoelectric signal and the fourth photoelectric signal; one group of photoelectric detectors is used for receiving the first photoelectric signal and the third photoelectric signal, and the other group of photoelectric detectors is used for receiving the second photoelectric signal and the fourth photoelectric signal;
and the signal processor is connected with the photoelectric detector, performs differential noise reduction based on the characteristic that the phases of the received vibration signals between the first photoelectric signal and the second photoelectric signal are opposite, recovers the sound wave of the sound source to be positioned with high fidelity, and positions the sound source of the sound wave based on the phase difference, the time difference and the distance between the received third photoelectric signal and the received fourth photoelectric signal.
6. The apparatus of claim 5, wherein the signal processor is configured to:
the differential noise reduction can be performed based on the characteristic that the phases of vibration signals between the first photoelectric signal and the second photoelectric signal are opposite, and the sound wave of the sound source to be positioned is recovered with high fidelity;
The azimuth angle and the distance of the sound source to be positioned can be determined based on the phase difference and the time difference between the third photoelectric signal and the fourth photoelectric signal, and the two-dimensional position of the sound source to be positioned is determined according to the azimuth angle and the distance.
7. The apparatus according to claim 6, wherein: the micro-nano optical fiber adopts an embedded structure on the acoustic membrane to improve the sensitivity of sensing the vibration of the acoustic membrane.
8. A sound source positioning method is characterized in that,
receiving four paths of optical signals transmitted by the micro-nano optical fiber sensing assembly;
performing photoelectric conversion on the optical signals to obtain a first photoelectric signal, a second photoelectric signal, a third photoelectric signal and a fourth photoelectric signal;
restoring sound waves of a sound source to be positioned by using the first photoelectric signal and the second photoelectric signal, determining azimuth angles and distances of the sound source to be positioned by using phase differences and time differences between a third photoelectric signal and a fourth photoelectric signal, and determining two-dimensional positions of the sound source to be positioned according to the azimuth angles and the distances;
the micro-nano optical fiber sensing assemblies are packaged at two ends of the acoustic wave coupling tube and comprise acoustic films packaged at two ends of the acoustic wave coupling tube and micro-nano optical fibers distributed on the acoustic films, wherein the micro-nano optical fibers are used for transmitting a first photoelectric signal, a second photoelectric signal, a third photoelectric signal and a fourth photoelectric signal respectively;
The first optical signal and the second optical signal are optical signals generated by driving the micro-nano optical fiber to vibrate by the sound films at two sides of the sound wave coupling tube under the action of sound waves of an external sound source, and are respectively recorded as a first optical signal and a second optical signal; when the acoustic films are subjected to external sound waves, a pressure is generated to opposite sides due to the coupling action of the sound wave coupling tube cavity, the sound films at the two sides are displaced again under the action of opposite sides pressure, and at the moment, the output light signals in the micro-nano optical fibers at the two sides of the sound wave coupling tube are respectively recorded as a third light signal and a fourth light signal.
9. An electronic device, comprising:
a processor;
a memory for storing processor-executable instructions;
wherein the processor is configured to invoke the memory-stored instructions to perform the method of claim 8;
and/or
Comprising a sound source localization device as claimed in any of the claims 1-7.
10. A computer readable storage medium having stored thereon computer program instructions, which when executed by a processor, implement the method of claim 8.
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Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09243445A (en) * | 1996-03-08 | 1997-09-19 | Mitsubishi Heavy Ind Ltd | Sound wave detector |
| US20010005439A1 (en) * | 1997-06-06 | 2001-06-28 | Kim Byoung Yoon | Acousto-optic filter |
| US20020041379A1 (en) * | 2000-08-15 | 2002-04-11 | Wuu-Wen Lin | On-line sagnac interferometric distributed fiber-optic leakage detection device |
| CN1837674A (en) * | 2006-04-14 | 2006-09-27 | 北京工业大学 | Apparatus and method for monitoring pipeline leakage based on distributed optical fiber acoustic sensing technology |
| CN101917655A (en) * | 2010-08-13 | 2010-12-15 | 浙江大学 | Resonant cavity microphone for detecting deep water sound waves |
| CN103472136A (en) * | 2013-08-30 | 2013-12-25 | 南京航空航天大学 | Acoustic emission sensing system based on single mode fiber coupler |
| CN105783996A (en) * | 2016-03-31 | 2016-07-20 | 华中科技大学 | Optical fiber sensor capable of measuring acoustic wave and pressure simultaneously |
| CN110703150A (en) * | 2019-10-10 | 2020-01-17 | 重庆大学 | Transformer internal fault detection and positioning method based on acoustic-vibration coupling signals |
| CN111141830A (en) * | 2019-12-28 | 2020-05-12 | 西安交通大学 | Micro-nano coupling optical fiber sensor-based linear positioning system and method |
-
2023
- 2023-04-03 CN CN202310346584.7A patent/CN116430315B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09243445A (en) * | 1996-03-08 | 1997-09-19 | Mitsubishi Heavy Ind Ltd | Sound wave detector |
| US20010005439A1 (en) * | 1997-06-06 | 2001-06-28 | Kim Byoung Yoon | Acousto-optic filter |
| US20020041379A1 (en) * | 2000-08-15 | 2002-04-11 | Wuu-Wen Lin | On-line sagnac interferometric distributed fiber-optic leakage detection device |
| CN1837674A (en) * | 2006-04-14 | 2006-09-27 | 北京工业大学 | Apparatus and method for monitoring pipeline leakage based on distributed optical fiber acoustic sensing technology |
| CN101917655A (en) * | 2010-08-13 | 2010-12-15 | 浙江大学 | Resonant cavity microphone for detecting deep water sound waves |
| CN103472136A (en) * | 2013-08-30 | 2013-12-25 | 南京航空航天大学 | Acoustic emission sensing system based on single mode fiber coupler |
| CN105783996A (en) * | 2016-03-31 | 2016-07-20 | 华中科技大学 | Optical fiber sensor capable of measuring acoustic wave and pressure simultaneously |
| CN110703150A (en) * | 2019-10-10 | 2020-01-17 | 重庆大学 | Transformer internal fault detection and positioning method based on acoustic-vibration coupling signals |
| CN111141830A (en) * | 2019-12-28 | 2020-05-12 | 西安交通大学 | Micro-nano coupling optical fiber sensor-based linear positioning system and method |
Non-Patent Citations (2)
| Title |
|---|
| 付文成: "基于微纳耦合光纤传感器的模态声发射源线性定位研究", 振动与冲击 * |
| 刘懿莹: "微纳耦合光纤模态声发射传感特性优化研", 仪器仪表学报 * |
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