Three-dimensional direction-of-arrival measurement system and method for sound field

Abstract

The present application provides a system and method for measuring the three-dimensional direction of arrival of a sound field, including: a laser generator emitting laser light, a spectrometer component dividing the laser light into a first parallel laser light and a second parallel laser light; causing the first parallel laser light and the second parallel laser light in the sound field to be measured to produce an interference effect, and obtaining an interfered light beam; a first detector collecting deflection information of the first parallel laser light passing through the sound field to be measured, and a second detector for collecting light intensity information of the interfered light beam; and obtaining the three-dimensional direction of arrival of the sound field to be measured based on the deflection information and light intensity information. Based on the acousto-optic effect, the present application can accurately determine the three-dimensional direction of arrival of the sound field by combining the phase information of the two parallel laser beams and the deflection information of the laser light passing through the sound field to be measured, thereby achieving measurement of the three-dimensional direction of arrival of the sound field.

Description

Technical Field

[0001] The present application relates to the technical field of sound field measurement, and in particular to a three-dimensional direction-of-arrival measurement system and method for a sound field. Background Art

[0002] The new measurement principle based on the acousto-optic effect has attracted widespread attention in the field of acoustic vector sensors because it can measure sound pressure gradients. The acousto-optic effect refers to the deflection phenomenon that occurs when a laser passes through an acoustic field. When the laser spot is much smaller than the wavelength of the sound wave, the laser will deflect along the direction of the sound pressure gradient at the sound wave frequency according to the light equation. By detecting the laser deflection, the sound wave can be measured, which can be applied to acoustic vector sensors to provide the possibility of accurate measurement.

[0003] However, laser deflection can only detect the arrival direction of the sound field in a specific plane, usually the projection on the detector plane, and lacks the detection of the three-dimensional arrival direction of the sound field. Summary of the Invention

[0004] Based on this, it is necessary to provide a three-dimensional direction of arrival measurement system and method for a sound field in order to partially solve the above technical problems.

[0005] In a first aspect, the present application provides a three-dimensional direction-of-arrival measurement system for a sound field, the system comprising:

[0006] A laser generating device, used for emitting laser;

[0007] a light splitting component for splitting the laser light emitted by the laser generating device into at least two parallel laser beams; the parallel laser beams include a first parallel laser beam and a second parallel laser beam; wherein a sound field to be measured exists in a first optical path of the first parallel laser beam, so that the first parallel laser beam is deflected after passing through the sound field to be measured;

[0008] an interference component, configured to generate an interference effect between the first parallel laser and the second parallel laser that pass through the sound field to be measured, and obtain an interfered light beam;

[0009] a detection assembly comprising a first detector and a second detector, wherein the detection plane of the first detector is relatively perpendicular to the first parallel laser and is used to collect deflection information of the first parallel laser passing through the sound field to be measured, and the second detector is used to collect light intensity information of the interfered light beam; and

[0010] A processor is used to process the deflection information and the light intensity information to obtain a three-dimensional direction of arrival of the sound field to be measured.

[0011] In one embodiment, the first detector is a position sensitive detector and the second detector is a photodiode.

[0012] In one embodiment, the beam splitter assembly includes a first beam splitter and a reflector, wherein the first beam splitter is used to split the laser emitted by the laser generating device into two laser beams, and the reflector is used to reflect one of the laser beams to be parallel to the other laser beam.

[0013] In one embodiment, the interference component includes a second beam splitter, a half-wave plate and a polarization beam splitter, wherein the second beam splitter is used to split the first parallel laser passing through the sound field to be measured into two laser beams. After the first laser beam reaches the first detector, the first detector collects deflection information of the first parallel laser passing through the sound field to be measured. After the second laser beam passes through the half-wave plate and reaches the polarization beam splitter, it is combined with the second parallel laser passing through the polarization beam splitter to form an interfered light beam.

[0014] In a second aspect, the present application provides a method for measuring a three-dimensional direction of arrival of a sound field, which is applied to a three-dimensional direction of arrival measurement system of a sound field as described in any one of the above items, the method comprising:

[0015] The laser generating device emits laser light, and the emitted laser light is divided into a first parallel laser light and a second parallel laser light via a light splitting component;

[0016] The first parallel laser passes through the sound field to be measured via the first optical path, and after reaching the first detector, the first detector collects deflection information of the first parallel laser after passing through the sound field to be measured;

[0017] Using an interference component, the second parallel laser light and the first parallel laser light passing through the sound field to be measured generate an interference effect, and using a second detector to collect light intensity information of the interfered light beam; and

[0018] The three-dimensional direction of arrival of the sound field to be measured is obtained based on the deflection information and the light intensity information.

[0019] In one embodiment, obtaining the three-dimensional direction of arrival of the sound field to be measured based on the deflection information and the light intensity information includes:

[0020] Demodulating the light intensity information to obtain phase information of the first parallel laser light relative to the second parallel laser light passing through the sound field to be measured;

[0021] A three-dimensional direction of arrival of the sound field to be measured is obtained based on the phase information and the deflection information.

[0022] In one embodiment, the deflection information includes lateral deflection information and longitudinal deflection information;

[0023] The obtaining of the three-dimensional direction of arrival of the sound field to be measured based on the phase information and the deflection information includes:

[0024] Obtaining a first-dimensional direction of arrival of the sound field to be measured based on the lateral deflection information, the phase information, and a preset wave number of the sound field to be measured;

[0025] Obtaining a second-dimensional direction of arrival of the sound field to be measured based on the longitudinal deflection information, the phase information, and a preset wave number of the sound field to be measured;

[0026] A third-dimensional direction of arrival of the sound field to be measured is determined based on the first-dimensional direction of arrival and the second-dimensional direction of arrival.

[0027] In one embodiment, the specific calculation formula for obtaining the three-dimensional direction of arrival of the sound field to be measured based on the phase information and the deflection information is as follows:

[0028]

[0029] Wherein, [k1, k2, k3] is the three-dimensional direction of arrival of the sound field to be measured, x(t) is the function of the change of the lateral deflection information over time, and y(t) is the function of the change of the longitudinal deflection information over time. (t) is a function of the phase information changing with time, and k is a preset wave number of the sound field to be measured.

[0030] In one embodiment, demodulating the light intensity information to obtain phase information of the first parallel laser light relative to the second parallel laser light passing through the sound field to be measured includes:

[0031] The light intensity information is demodulated based on polarization interference to obtain phase information of the first parallel laser light passing through the sound field to be measured relative to the second parallel laser light.

[0032] In one embodiment, the three-dimensional arrival direction of the sound field to be measured refers to a unit direction vector in a preset Cartesian coordinate system, where the preset Cartesian coordinate system uses the detection plane of the first detector as the XOY plane and the Z axis is perpendicular to the detection plane.

[0033] The three-dimensional wave direction measurement system of the sound field provided in the embodiment of the present application divides the laser into two parallel laser beams through the splitter component, and deflects one of the parallel laser beams through the sound field to be measured, and causes the deflected parallel laser beam to interfere with the other parallel laser beam, so that the phase information of the two parallel laser beams can be determined by detecting the light intensity information of the interfered light beam by the detector. Based on the acousto-optic effect, the three-dimensional wave direction of the sound field can be accurately determined by combining the phase information of the two parallel laser beams and the deflection information of the laser through the sound field to be measured, thereby realizing the measurement of the three-dimensional wave direction of the sound field. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0035] Figure 1 A schematic diagram of the structure of a three-dimensional direction-of-arrival measurement system for a sound field provided in an embodiment of the present application;

[0036] Figure 2 A schematic structural diagram of a light splitting component provided in an embodiment of the present application;

[0037] Figure 3 A schematic structural diagram of an interference assembly provided in an embodiment of the present application;

[0038] Figure 4 A schematic diagram of light path propagation in a three-dimensional direction-of-arrival measurement system provided in an embodiment of the present application;

[0039] Figure 5 A schematic flow chart of the steps of a method for measuring a three-dimensional direction of arrival of a sound field provided in an embodiment of the present application;

[0040] Figure 6 A schematic diagram of a process flow for obtaining a three-dimensional direction of arrival based on deflection information and light intensity information provided in an embodiment of the present application;

[0041] Figure 7 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0042] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without making creative efforts are within the scope of protection of this application.

[0043] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include one or more of the described features. In the description of this application, "plurality" means two or more, unless otherwise specifically specified.

[0044] In the description of this application, the word "for example" is used to mean "used as an example, illustration or illustration". Any embodiment described in this application as "for example" is not necessarily to be construed as being more preferred or advantageous than other embodiments. The following description is given to enable any person skilled in the art to implement and use the present invention. In the following description, details are listed for the purpose of explanation. It should be understood that a person of ordinary skill in the art can recognize that the present invention can be implemented without using these specific details. In other examples, well-known structures and processes are not elaborated in detail to avoid obscuring the description of the present invention with unnecessary details. Therefore, the present invention is not intended to be limited to the embodiments shown, but is consistent with the widest scope consistent with the principles and features disclosed in this application.

[0045] To facilitate understanding of the three-dimensional direction of arrival measurement system and method for the sound field provided in the embodiments of the present application, the three-dimensional direction of arrival measurement scenario of the sound field is first described below. Specifically, by measuring the three-dimensional direction of arrival of the sound source, the orientation of the target sound source can be directly determined. It is currently widely used in submarine oil field exploration, unmanned submersible detection, underwater acoustic communication enhancement, and underwater robot navigation. In related technologies, the estimation of the direction of arrival of sound waves is mainly based on an ultrasonic transducer array and an optical fiber transducer array based on the piezoelectric effect, that is, an array is formed by multiple sound sensors, and the direction of arrival of the sound is obtained through beamforming.

[0046] Research on the acousto-optic effect has garnered widespread attention in the field of acoustic vector sensors due to its novel measurement principle, which can measure sound pressure gradients. Specifically, the acousto-optic effect refers to the deflection phenomenon that occurs when a laser passes through an acoustic field. If the laser spot size is significantly smaller than the acoustic wavelength, the laser will deflect along the direction of the acoustic pressure gradient at the acoustic frequency according to the ray equation. Therefore, related technologies have proposed using a detector to detect the laser's deflection after it passes through the acoustic field to determine the direction of arrival of the acoustic field. However, this approach only measures the projection direction of the acoustic field's direction of arrival within the detection plane, meaning it can only measure information about the direction of arrival of the acoustic wave in two dimensions. This makes it suitable for two-dimensional acoustic vector sensors. To obtain information about the direction of arrival of the acoustic wave in three dimensions, it is typically necessary to determine the projection direction of the acoustic field's direction of arrival on multiple detection planes. Based on these projection directions, the three-dimensional direction of arrival information can then be inferred. However, this approach is complex to operate, making it difficult to calculate the three-dimensional direction of arrival of the acoustic wave, especially in complex measurement fields such as underwater acoustic measurement.

[0047] In order to solve the above problems, the present application provides a three-dimensional wave arrival direction measurement system and method for the sound field, which aims to quickly realize the measurement of the three-dimensional wave arrival direction of the sound field by combining deflection information and phase information, as described in detail below.

[0048] For details, please refer to Figure 1 , Figure 1 A schematic structural diagram of a three-dimensional direction-of-arrival measurement system for a sound field provided in an embodiment of the present application is described in detail as follows.

[0049] In the embodiment of the present application, the three-dimensional direction of arrival measurement system of the sound field mainly includes:

[0050] A laser generating device 110, for emitting laser light;

[0051] A beam splitting component 120 is configured to split the laser light emitted by the laser generating device into at least two parallel laser beams; the parallel laser beams include a first parallel laser beam and a second parallel laser beam; wherein a sound field to be measured exists in a first optical path of the first parallel laser beam, so that the first parallel laser beam is deflected after passing through the sound field to be measured;

[0052] An interference component 130 is configured to generate an interference effect between the first parallel laser and the second parallel laser that pass through the sound field to be measured, and obtain an interfered light beam;

[0053] The detection assembly 140 includes a first detector 141 and a second detector 142. The detection plane of the first detector is relatively perpendicular to the first parallel laser and is used to collect deflection information of the first parallel laser passing through the sound field to be measured. The second detector is used to collect light intensity information of the interfered light beam; and

[0054] The processor 150 is configured to process the deflection information and the light intensity information to obtain a three-dimensional direction of arrival of the sound field to be measured.

[0055] In the embodiment of the present application, in order to facilitate the understanding of the optical path of the laser in the above system, the following will be combined with Figure 1 The optical path shown is described in detail.

[0056] Specifically, the laser generating device is a type of laser that can stably emit laser light of a specific wavelength. After the laser light passes through the sound field to be measured, it will be affected by the sound field and deflected. In order to improve the measurement accuracy and avoid the interference of the laser on the sound field, the laser light emitted by the laser can be a narrow linewidth, high-intensity laser to reduce the measurement error caused by the laser.

[0057] After the laser generating device emits the laser, the laser passes through a group of light splitting components 120, thereby being divided into two parallel laser beams, one of which passes through the sound field to be measured as a measuring arm, while the other parallel laser does not pass through the sound field to be measured and serves as a reference arm. Specifically, the embodiment of the present application does not limit the specific structure of the light splitting component 120. Any component that can split a laser beam into two parallel laser beams is within the scope of protection claimed by this application. Of course, based on complex measurement conditions, such as the need for simplified structure in underwater acoustic measurement environments, the present application further provides a feasible light splitting component. In one embodiment, please refer to Figure 2 , Figure 2 A structural schematic diagram of a light splitting component 120 provided in an embodiment of the present application is described in detail as follows.

[0058] In an embodiment of the present application, the spectroscopic component 120 mainly includes a first spectrometer 121 and a reflector 122, wherein the first spectrometer 121 is mainly used to split the laser emitted by the laser generating device into two laser beams, one of which serves as a first parallel laser, and the other laser beam, when passing through the reflector 112, is reflected by the reflector 122 to form another laser beam parallel to the first parallel laser, that is, a second parallel laser.

[0059] Of course, the aforementioned light splitting component is only one feasible implementation solution, and it is also feasible to split a laser beam into two parallel laser beams by other means. This embodiment of the present application does not limit this.

[0060] After obtaining at least two parallel laser beams through the spectrometer, at least one of the parallel laser beams, namely the first parallel laser beam, will serve as a reference arm and pass through the sound field to be measured. Under the influence of the sound field, it will be deflected, usually causing slight changes in the direction and phase of the laser. For example, Figure 1 In the figure, after the first parallel laser passes through the sound field to be measured, the dotted line represents the ideal propagation direction of the first parallel laser when it is not deflected, and the solid line represents the actual propagation direction of the first parallel laser after it passes through the sound field and is deflected.

[0061] On this basis, in order to measure the deflection information of the first parallel laser after passing through the acoustic field, in the embodiment of the present application, the deflection information of the first parallel laser is collected by the first detector 141. Specifically, the detection plane of the first detector 141 is usually set perpendicular to the first parallel laser (before deflection) and the second parallel laser. That is, after the first parallel laser is deflected after passing through the acoustic field and reaches the first detector 141, the incident point will deviate from the theoretical detection center, so that the deflection information of the laser can be described based on the deviation.

[0062] Of course, considering that sound waves will also interfere with the phase information of the laser, in order to achieve the measurement of the three-dimensional arrival direction of the sound wave, the interference component 130 can also be used to make the first parallel laser and the second parallel laser after deflection produce an interference effect, thereby modulating the phase information of the two groups of parallel lasers to the light intensity, and then determining the phase information of the two groups of parallel lasers by measuring the light intensity information of the laser beam after interference, that is, it usually refers to the phase change information of the first parallel laser after the phase of the sound field to be measured changes relative to the second parallel laser that has not passed through the sound field.

[0063] Specifically, based on the complex measurement conditions, such as the requirement for simplified structure in underwater acoustic measurement environment, in one embodiment, refer to Figure 3 , Figure 3 A structural diagram of an interference assembly 130 provided in an embodiment of the present application is described in detail as follows.

[0064] Specifically, considering that it is necessary to measure the deflection information of the first parallel laser and to make the deflected first parallel laser interfere with the second parallel laser, in the embodiment of the present application, the interference component 130 includes a second beam splitter 131, wherein the second beam splitter 131 is used to split the first parallel laser that passes through the sound field to be measured into two laser beams again, wherein the first laser beam can be used to collect the deflection information of the first parallel laser after reaching the first detector, and the other laser beam changes the polarization state of the light wave after being processed by the half-wave plate 132, so that after passing through the polarization beam splitter 133, it is recombined with the second parallel laser that passes through the polarization beam splitter 133 to form an interfered light beam. It can be understood that since the phase information of the first parallel laser will change after passing through the sound field, the first parallel laser and the second parallel laser will form a laser beam with a changed intensity in response to the phase change after interference, so the phase information of the two parallel laser beams can be determined by detecting the light intensity of the interfered light beam.

[0065] In order to measure the phase information of two parallel laser beams, in an embodiment of the present application, the detector 140 may further include a second detector 142, which detects the light intensity irradiated on the second detector to demodulate and restore the phase change information of the first parallel laser relative to the second parallel laser.

[0066] Specifically, in one embodiment, the first detector 141 can be a position sensitive detector (PSD), so that the deflection information of the first parallel laser can be accurately determined by the position deflection of the incident point of the first parallel laser on the first detector, and the second detector can be a photodiode (PD).

[0067] On the basis of the above, the deflection information detected by the first detector 141 and the light intensity information detected by the second detector 142 will be transmitted to the processor 150, so that the deflection information and light intensity information can be processed into the three-dimensional arrival direction of the sound source according to a pre-set algorithm in the processor 150. Of course, it should be noted that the deflection information and light intensity information measured here are specifically expressed as function information that changes with time, and the specific calculation process and principle will be explained later.

[0068] In order to clearly understand the complete structural diagram of the three-dimensional direction of arrival measurement system provided by this application, please refer to Figure 4 , Figure 4 This is a schematic diagram of light path propagation in a three-dimensional direction of arrival measurement system provided in an embodiment of the present application. The details are as follows.

[0069] See also Figure 4 When the laser emits a laser, it first passes through the beam splitter 1, which splits the laser beam into two beams, corresponding to the measuring arm (i.e., the first parallel laser) and the reference arm (the second parallel laser). The measuring arm is affected by the sound field emitted by the sound source and will deflect and change phase. The deflection will be recorded by the PSD (position sensitive detector, also known as the first detector). The detection path is that the first parallel laser passes through the sound field and then passes through the beam splitter 2 to reach the PSD. The phase change is measured by two parallel lasers, one of which is the first parallel laser passing through the beam splitter 2 downward through the half-wave plate to reach the polarization beam splitter, and the other is the second parallel laser passing through the beam splitter 1 downward and then reflected by the reflector to reach the polarization beam splitter. The two laser beams pass through the polarization beam splitter to produce an interference effect to form an interfered laser beam and then reach the PD (photodiode, also known as the second detector). The interference effect generated by these two lasers can modulate the phase change information of the first parallel laser to the light intensity, so that the PD can record the phase information. Among them, if the detection plane of the PSD is defined as the XOY plane, and the Z axis is perpendicular to the XOY to form a Cartesian coordinate system, then the deflection information is related to the X-axis component and the Y-axis component in the direction of the sound source, while the phase information is related to the Z-axis component in the direction of the sound source.

[0070] It can be seen that the three-dimensional wave direction measurement system provided above is used to split the laser into two parallel laser beams through the spectroscopic component, and one of the parallel laser beams is deflected through the sound field to be measured, and the deflected parallel laser beam is interfered with the other parallel laser beam, so that the light intensity information of the light beam after interference can be detected by the detector to determine the phase information of the two parallel laser beams. Based on the acousto-optic effect, the three-dimensional wave direction of the sound field can be accurately determined by combining the phase information of the two parallel laser beams and the deflection information of the laser through the sound field to be measured, thereby realizing the measurement of the three-dimensional wave direction of the sound field. In addition, the components involved in the measurement system provided by the present application are simple in structure and do not require the use of large-scale detection equipment. It is particularly suitable for accurate measurement of the three-dimensional wave direction of the sound field in complex environments, such as underwater acoustic environments.

[0071] In order to clearly understand the measurement principle and corresponding measurement method of the three-dimensional direction of arrival measurement system provided by the embodiment of the present application, the following will be combined with the above Figures 1 to 4 The provided 3D direction of arrival measurement system further provides a specific implementation process of a 3D direction of arrival measurement method. Of course, to facilitate understanding that the measurement method provided in the embodiments of this application can be used to implement 3D direction of arrival measurement, the following first describes the derivation process in conjunction with relevant technical principles, as detailed below.

[0072] Specifically, consider the following sound wave function:

[0073]

[0074] Among them, p(r, t) usually represents the sound pressure at a certain position and time, r is the position variable, which can usually be described by the coordinates (x, y, z) in the three-dimensional wave direction, and the corresponding [k1, k2, k3] can be understood as the unit direction vector of the sound source in a specific coordinate system, that is, the three-dimensional wave direction that needs to be solved in this application, wherein, [k1, k2, k3] = [cos(α)cos(θ), cos(α)sin(θ), sin(α)], that is, based on the three-dimensional wave direction obtained in this application, the pitch angle α and azimuth angle θ of the sound source relative to the origin can be further solved to achieve the tracing of the sound source position, and t is the time variable. In addition, k is the wave number of the sound source, which can usually be calculated based on the sound speed c in the medium and the angular frequency ω of the sound wave, that is, k = ω / c.

[0075] On this basis, the measuring arm, that is, the first parallel laser, is affected by the sound wave. This influencing factor can be mathematically described as the light equation, that is:

[0076]

[0077] Where dl represents the path element in the beam path, is the Laplace operator, so combining the above solutions can be obtained:

[0078] x(t)=kk1L·sinc(kk3L / 2)e-jωt

[0079] y(t)=kk2L·sinc(kk3L / 2)e-jωt

[0080] Here, x(t) can be understood as the time-varying function of the transverse deflection information when the detector's detection plane is considered the XOY plane, while the corresponding y(t) is the time-varying function of the longitudinal deflection information. Furthermore, L is the effective acousto-optic range, which is the length of the reference arm affected by the acoustic wave.

[0081] For the z-axis direction perpendicular to the XOY plane, assuming that the laser propagates in a straight line, the phase function of the first parallel laser after passing through the sound field to be measured is:

[0082]

[0083] After the phase function is modulated to the light intensity information, the relationship between the obtained light intensity information and the phase function is:

[0084]

[0085] Therefore, the phase function of the first parallel laser light can be demodulated from the measured light intensity information z(t).

[0086] Therefore, the three-dimensional direction of arrival [k1, k2, k3] of the sound source can be determined by the aforementioned measured quantities x(t), y(t), and z(t). Figure 5 , Figure 5 This is a schematic flow chart of the steps of a method for measuring the three-dimensional direction of arrival of a sound field provided in an embodiment of the present application. Specifically, the method is mainly applied to the three-dimensional direction of arrival measurement system of the sound field provided in any of the aforementioned embodiments. The method includes steps S510 to S540:

[0087] S510 , controlling the laser generating device to emit laser light, and dividing the emitted laser light into a first parallel laser light and a second parallel laser light via a light splitting component.

[0088] In an embodiment of the present application, when the laser generating device emits laser, it will split the emitted laser into a first parallel laser and a second parallel laser through a spectroscopic component, that is, forming a measuring arm and a reference arm, wherein the spectroscopic component can be in the form of a first spectroscope and a reflector. After the first spectroscope splits the laser into two beams, one of the beams will be reflected by the reflector to form a laser parallel to the other beam, thereby serving as the first parallel laser and the second parallel laser.

[0089] S520: The first parallel laser passes through the sound field to be measured via the first optical path, and after reaching the first detector, the first detector collects deflection information of the first parallel laser after passing through the sound field to be measured.

[0090] In an embodiment of the present application, the first parallel laser serving as a measuring arm passes through the sound field to be measured via a first optical path, and when it reaches a first detector, such as a position sensitive detector PSD, the position offset information of the incident point sensed by the first detector is used to determine the deflection information of the first parallel laser after passing through the sound field to be measured, that is, a function of the change in position offset over time.

[0091] S530: Using an interference component, the second parallel laser light and the first parallel laser light passing through the sound field to be measured generate an interference effect, and using a second detector to collect light intensity information of the interfered light beam.

[0092] In an embodiment of the present application, in addition to obtaining the deflection information of the first parallel laser after passing through the sound field to be measured by the measuring arm, an interference effect is further generated between the second parallel laser and the first parallel laser passing through the sound field to be measured through an interference component, so as to modulate the phase change information of the first parallel laser passing through the sound field to be measured to the light intensity, so that the light intensity information of the light beam after interference can be collected by the second detector to restore the phase change information of the first parallel laser, wherein the second detector can adopt a small detection device, such as the photodiode PD mentioned above.

[0093] S540: Obtain a three-dimensional direction of arrival of the sound field to be measured based on the deflection information and the light intensity information.

[0094] In the embodiment of the present application, combined with the above-mentioned related description, it can be seen that based on the deflection information collected by the first detector and the light intensity information collected by the second detector, the three-dimensional wave arrival direction of the sound field to be measured can be calculated.

[0095] Specifically, in one embodiment, in combination with the above related description, it can be seen that Figure 6 , Figure 6 A flowchart of a method for obtaining a three-dimensional direction of arrival based on deflection information and light intensity information is provided in an embodiment of the present application, specifically including steps S610 to S620:

[0096] S610 , demodulating the light intensity information to obtain phase information of the first parallel laser light passing through the sound field to be measured relative to the second parallel laser light.

[0097] In the embodiment of the present application, combined with the above-mentioned related description, it can be known that the phase information can be modulated into the light intensity information through the interference effect, so that the light intensity information after interference can be detected by a portable photodiode, and the phase information of the first parallel laser relative to the second parallel laser passing through the sound field to be measured can be recovered by demodulation, that is, according to the functional relationship between the light intensity information and the phase The phase function of the first parallel laser is obtained by demodulating the light intensity information z(t)

[0098] Specifically, there are many ways of demodulation, such as phase-shift interferometry, heterodyne / homodyne detection, spatial carrier method, etc. However, in the embodiment of the present application, taking the interference component including a half-wave plate and a polarization beam splitter as an example, at this time, the demodulation of the light intensity information can be achieved based on the polarization demodulation method, that is, the demodulation of the light intensity information to obtain the phase information of the first parallel laser relative to the second parallel laser passing through the sound field to be measured includes:

[0099] The light intensity information is demodulated based on polarization interference to obtain phase information of the first parallel laser light passing through the sound field to be measured relative to the second parallel laser light.

[0100] Of course, it should be noted that, in the process of the above-mentioned polarization interference demodulation, it is often necessary to calibrate the polarization state, which will not be described in detail in the embodiments of the present application.

[0101] S620: Obtain a three-dimensional direction of arrival of the sound field to be measured based on the phase information and the deflection information.

[0102] On the basis of the above, the phase information is demodulated from the light intensity information, and combined with the deflection information, the three-dimensional wave arrival direction of the sound field to be measured can be obtained.

[0103] Specifically, in combination with the aforementioned formula, it can be seen that the deflection information generally includes lateral deflection information and longitudinal deflection information on the XOY plane with the detection plane as the detection plane. That is, the step of obtaining the three-dimensional direction of arrival of the sound field to be measured based on the phase information and the deflection information specifically includes:

[0104] Obtaining a first-dimensional direction of arrival of the sound field to be measured based on the lateral deflection information, the phase information, and a preset wave number of the sound field to be measured;

[0105] Obtaining a second-dimensional direction of arrival of the sound field to be measured based on the longitudinal deflection information, the phase information, and a preset wave number of the sound field to be measured;

[0106] A third-dimensional direction of arrival of the sound field to be measured is determined based on the first-dimensional direction of arrival and the second-dimensional direction of arrival.

[0107] Specifically, combined with the above formula:

[0108] x(t)=kk1L·sinc(kk3L / 2)e -j ω t

[0109] y(t)=kk2L·sinc(kk3L / 2)e -j ω t

[0110]

[0111] You can get:

[0112]

[0113] The definitions of the various parameters in the above formulas have been specifically provided above and will not be repeated here in the embodiments of the present application.

[0114] In addition, the three-dimensional wave arrival direction of the sound field to be measured provided in this application refers to a unit direction vector in a preset Cartesian coordinate system, and the preset Cartesian coordinate system uses the detection plane of the first detector as the XOY plane, and the Z axis is perpendicular to the detection plane.

[0115] The embodiment of the present application provides a method for measuring the three-dimensional direction of arrival of a sound field. A laser is divided into two parallel laser beams by a spectroscopic component, and one of the parallel laser beams is deflected through the sound field to be measured, and the deflected parallel laser beam is interfered with the other parallel laser beam. The phase information of the two parallel laser beams can be determined by detecting the light intensity information of the interfered light beams through a detector. Based on the acousto-optic effect, the three-dimensional direction of arrival of the sound field can be accurately determined by combining the phase information of the two parallel laser beams and the deflection information of the laser through the sound field to be measured, thereby realizing the measurement of the three-dimensional direction of arrival of the sound field.

[0116] Of course, in order to implement the above-mentioned measurement process of the three-dimensional direction of arrival, in a feasible implementation scheme, an electronic device is also provided. The electronic device is electrically connected to different components of the three-dimensional direction of arrival measurement system of the sound field, such as the laser generator, the first detector, and the second detector, to control each component, or collect information detected by each detector, such as deflection information and light intensity information, so as to complete the calculation of the three-dimensional direction of arrival of the sound source based on the calculation process of the three-dimensional direction of arrival measurement method provided in this application. For example, in one embodiment, the memory of the electronic device may store program modules for executing each step in the above-mentioned embodiment. The computer program composed of each program module enables the electronic device to execute the steps of the method for measuring the light beam deflection angle of each embodiment of the present application described in this specification.

[0117] For example, see Figure 7 , Figure 7 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application. The electronic device includes a processor, a memory, and a network interface connected via a system bus. The processor of the electronic device is used to provide computing and control capabilities. The memory of the electronic device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and computer program in the non-volatile storage medium. The network interface of the electronic device is used to communicate with external electronic devices via a network connection. When the computer program is executed by the processor, it implements a method for measuring the three-dimensional direction of arrival of a sound source, for example:

[0118] Controlling the laser generating device to emit laser light, and dividing the emitted laser light into a first parallel laser light and a second parallel laser light via a light splitting component;

[0119] The first parallel laser passes through the sound field to be measured via the first optical path, and after reaching the first detector, the first detector collects deflection information of the first parallel laser after passing through the sound field to be measured;

[0120] Using an interference component, the second parallel laser light and the first parallel laser light passing through the sound field to be measured generate an interference effect, and using a second detector to collect light intensity information of the interfered light beam; and

[0121] The three-dimensional direction of arrival of the sound field to be measured is obtained based on the deflection information and the light intensity information.

[0122] Those skilled in the art will understand that Figure 7 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the electronic device to which the solution of the present application is applied. The specific electronic device may include more or fewer components than shown in the figure, or combine certain components, or have a different component arrangement.

[0123] In some embodiments of the present application, a computer-readable storage medium is provided, storing a computer program. The computer program is loaded by a processor, causing the processor to execute any of the methods for determining the three-dimensional direction of arrival of a sound source provided in the embodiments of the present application, for example:

[0124] Controlling the laser generating device to emit laser light, and dividing the emitted laser light into a first parallel laser light and a second parallel laser light via a light splitting component;

[0125] The first parallel laser passes through the sound field to be measured via the first optical path, and after reaching the first detector, the first detector collects deflection information of the first parallel laser after passing through the sound field to be measured;

[0126] Using an interference component, the second parallel laser light and the first parallel laser light passing through the sound field to be measured generate an interference effect, and using a second detector to collect light intensity information of the interfered light beam; and

[0127] The three-dimensional direction of arrival of the sound field to be measured is obtained based on the deflection information and the light intensity information.

[0128] Those skilled in the art will appreciate that all or part of the processes in the above-mentioned embodiment methods can be implemented by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Any reference to memory, storage, information library or other media used in the embodiments provided in this application may include at least one of non-volatile and volatile memory. Non-volatile memory may include read-only memory (ROM), magnetic tape, floppy disk, flash memory or optical memory, etc. Volatile memory may include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM).

[0129] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0130] The above is a detailed introduction to a device and method for measuring the deflection angle of a light beam provided in an embodiment of the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A three-dimensional direction of arrival measurement system for a sound field, characterized in that: The system comprises: A laser generating device, used for emitting laser; a light splitting component for splitting the laser light emitted by the laser generating device into at least two parallel laser beams; the parallel laser beams include a first parallel laser beam and a second parallel laser beam; wherein a sound field to be measured exists in a first optical path of the first parallel laser beam, so that the first parallel laser beam is deflected after passing through the sound field to be measured; an interference component, configured to generate an interference effect between the first parallel laser and the second parallel laser that pass through the sound field to be measured, and obtain an interfered light beam; a detection assembly comprising a first detector and a second detector, wherein the detection plane of the first detector is relatively perpendicular to the first parallel laser and is used to collect deflection information of the first parallel laser passing through the sound field to be measured, and the second detector is used to collect light intensity information of the interfered light beam; and A processor is used to process the deflection information and the light intensity information to obtain a three-dimensional direction of arrival of the sound field to be measured.

2. The system according to claim 1, wherein: The first detector is a position sensitive detector, and the second detector is a photodiode.

3. The system according to claim 1, wherein: The beam splitter assembly includes a first beam splitter and a reflector, wherein the first beam splitter is used to split the laser emitted by the laser generating device into two laser beams, and the reflector is used to reflect one of the laser beams to be parallel to the other laser beam.

4. The system according to claim 1, wherein: The interference component includes a second beam splitter, a half-wave plate and a polarization beam splitter, wherein the second beam splitter is used to split the first parallel laser passing through the sound field to be measured into two laser beams. After the first laser beam reaches the first detector, the first detector collects deflection information of the first parallel laser passing through the sound field to be measured. After the second laser beam passes through the half-wave plate and reaches the polarization beam splitter, it is combined with the second parallel laser passing through the polarization beam splitter to form an interfering light beam.

5. A method for measuring the three-dimensional direction of arrival of a sound field, characterized in that: The method applied to the three-dimensional direction-of-arrival measurement system of a sound field according to any one of claims 1 to 4 comprises: Controlling the laser generating device to emit laser light, and dividing the emitted laser light into a first parallel laser light and a second parallel laser light via a light splitting component; The first parallel laser passes through the sound field to be measured via the first optical path, and after reaching the first detector, the first detector collects deflection information of the first parallel laser after passing through the sound field to be measured; Using an interference component, the second parallel laser light and the first parallel laser light passing through the sound field to be measured generate an interference effect, and using a second detector to collect light intensity information of the interfered light beam; and The three-dimensional direction of arrival of the sound field to be measured is obtained based on the deflection information and the light intensity information.

6. The method according to claim 5, characterized in that The obtaining of the three-dimensional direction of arrival of the sound field to be measured based on the deflection information and the light intensity information includes: Demodulating the light intensity information to obtain phase information of the first parallel laser light relative to the second parallel laser light passing through the sound field to be measured; A three-dimensional direction of arrival of the sound field to be measured is obtained based on the phase information and the deflection information.

7. The method according to claim 6, characterized in that The deflection information includes lateral deflection information and longitudinal deflection information; The obtaining of the three-dimensional direction of arrival of the sound field to be measured based on the phase information and the deflection information includes: Obtaining a first-dimensional direction of arrival of the sound field to be measured based on the lateral deflection information, the phase information, and a preset wave number of the sound field to be measured; Obtaining a second-dimensional direction of arrival of the sound field to be measured based on the longitudinal deflection information, the phase information, and a preset wave number of the sound field to be measured; A third-dimensional direction of arrival of the sound field to be measured is determined based on the first-dimensional direction of arrival and the second-dimensional direction of arrival.

8. The method according to claim 7, characterized in that The specific calculation formula for obtaining the three-dimensional direction of arrival of the sound field to be measured based on the phase information and the deflection information is as follows: Wherein, [k1, k2, k3] is the three-dimensional direction of arrival of the sound field to be measured, x(t) is the function of the change of the lateral deflection information over time, and y(t) is the function of the change of the longitudinal deflection information over time. is a function of the phase information changing with time, and k is a preset wave number of the sound field to be measured.

9. The method according to claim 6, characterized in that The demodulating the light intensity information to obtain phase information of the first parallel laser light relative to the second parallel laser light passing through the sound field to be measured includes: The light intensity information is demodulated based on polarization interference to obtain phase information of the first parallel laser light passing through the sound field to be measured relative to the second parallel laser light.

10. The method according to claim 6, characterized in that The three-dimensional arrival direction of the sound field to be measured refers to a unit direction vector in a preset Cartesian coordinate system, where the detection plane of the first detector is used as the XOY plane, and the Z axis is perpendicular to the detection plane.

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