System and method for measuring three-dimensional direction of arrival of sound field

Abstract

The invention provides a three-dimensional direction-of-arrival measurement system and method for a sound field, and the method comprises the steps: enabling a laser generation device to emit laser, and enabling a light splitting assembly to divide the laser into first parallel laser and second parallel laser; enabling the first parallel laser and the second parallel laser of the sound field to be measured to generate an interference effect, and obtaining an interfered light beam; the first detector collects deflection information of the first parallel laser penetrating through the sound field to be detected, and the second detector is used 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 the light intensity information. 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 beams of parallel laser and the deflection information of the laser generated by the sound field to be measured, and the measurement of the three-dimensional direction of arrival of the sound field is realized.

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 the sound pressure gradient. 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. The sound wave can be measured by detecting the laser deflection, which can be applied to acoustic vector sensors to make accurate measurement possible.

[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 wave arrival direction measurement system and method for the 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 is used to split the laser light emitted by the laser generating device into at least two parallel laser beams; the parallel laser light includes a first parallel laser light and a second parallel laser light; wherein a sound field to be measured exists on a first optical path of the first parallel laser light, so that the first parallel laser light is deflected after passing through the sound field to be measured;

[0008] An interference component, used for causing the first parallel laser and the second parallel laser that pass through the sound field to be measured to produce an interference effect, and obtaining an interfered light beam;

[0009] A detection assembly, comprising a first detector and a second detector, wherein a 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 the three-dimensional wave arrival direction 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, and 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, and 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 three-dimensional direction of arrival measurement method for a sound field, which is applied to a three-dimensional direction of arrival measurement system for a sound field as described in any one of the above items, and the method comprises:

[0015] The laser generating device emits laser light, and splits the emitted laser light into a first parallel laser light and a second parallel laser light via a beam 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 the 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 light beam after the interference; 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 passing through the sound field to be measured relative to the second parallel laser light;

[0021] The 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 comprises:

[0024] Obtaining a first-dimensional wave arrival direction 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 wave arrival direction 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 wave arrival direction of the sound field to be measured, x(t) is the function of the change of the lateral deflection information over time, y(t) is the function of the change of the longitudinal deflection information over time, (t) is a function of the change of the phase information over time, and k is a preset wave number of the sound field to be measured.

[0030] In one embodiment, the 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 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, wherein the preset Cartesian coordinate system takes 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 a spectroscopic component, and deflects one of the parallel laser beams through the sound field to be measured, and interferes with the other parallel laser beam after deflection, so that 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, and 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 drawings required for use in the description of the embodiments will be briefly introduced below. 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 diagram of the structure of a light splitting component provided in an embodiment of the present application;

[0037] Figure 3 A schematic diagram of the structure of an interference component 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 diagram 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 the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work 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 as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, "plurality" means two or more, unless otherwise clearly and specifically defined.

[0044] In the description of the present application, the word "for example" is used to mean "used as an example, illustration or explanation". Any embodiment described as "for example" in the present application is not necessarily to be construed as being more preferred or advantageous than other embodiments. The following description is given to enable any technician in the field 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 will not be 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 the present application.

[0045] To facilitate understanding of the three-dimensional direction of arrival measurement system and method of the sound field provided in the embodiment 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 seabed oil field exploration, unmanned submersible detection, underwater acoustic communication enhancement, and underwater robot navigation. The estimation of the direction of arrival of sound waves in related technologies 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 using multiple sound sensors to obtain the direction of arrival of the sound through beamforming.

[0046] With the research on the acousto-optic effect, it has received widespread attention in the field of acoustic vector sensors because the new measurement principle can measure the acoustic pressure gradient. Specifically, the acousto-optic effect refers to the deflection phenomenon that occurs when the laser passes through the sound field. Among them, if 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. Therefore, the relevant technology proposes to use the laser to detect the deflection information of the laser through the detector after passing through the sound field to determine the wave arrival direction of the sound field, but this method can only detect the projection direction of the wave arrival direction of the sound field in the detection plane, that is, it can only measure the information of the wave arrival direction of the sound wave in two dimensions, that is, it can be used as a two-dimensional acoustic vector sensor. If it is necessary to obtain the information of the wave arrival direction of the sound wave in the three-dimensional dimension, it is usually necessary to determine the projection direction of the wave arrival direction of the sound field on multiple detection planes, so as to reversely obtain the information of the wave arrival direction of the sound wave in the three-dimensional dimension based on the projection direction of multiple detection planes, but this method is complicated to operate, especially in complex measurement fields such as underwater acoustic measurement, it is not convenient to calculate the three-dimensional wave arrival direction of the sound wave.

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

[0052] An interference component 130, used for causing the first parallel laser and the second parallel laser that pass through the sound field to be measured to produce an interference effect, and obtaining an interfered light beam;

[0053] A detection assembly 140, comprising a first detector 141 and a second detector 142, wherein a 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

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

[0055] In the embodiments 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 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 does not pass through the sound field to be measured and serves as a reference arm. Specifically, the embodiments of the present application do 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 the present application. Of course, based on complex measurement conditions, such as the need to simplify the structure in an underwater acoustic measurement environment, 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 the embodiment of the present application, the spectroscopic component 120 mainly includes a first spectroscope 121 and a reflector 122, wherein the first spectroscope 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, i.e., a second parallel laser.

[0059] Of course, the above-mentioned light splitting component is only a feasible implementation scheme, and it is also feasible to split a laser beam into two parallel laser beams by other methods. The embodiment of the present application is not limited here.

[0060] After obtaining at least two parallel laser beams through the beam splitter, at least one of the parallel laser beams, namely the first parallel laser beam, will serve as a reference arm, pass through the sound field to be measured, and be deflected under the influence of the sound field, 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 sound 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 passes through the sound field and is deflected, it reaches the first detector 141, and 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, so that the phase information of the two groups of parallel lasers can be modulated to the light intensity, and the phase information of the two groups of parallel lasers can be determined 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 complex measurement conditions, such as the requirement for simplified structure in an underwater acoustic measurement environment, in one embodiment, refer to Figure 3 , Figure 3 A structural schematic 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 passing 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 passing through the polarization beam splitter 133 into 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 illumination intensity of the interfered light beam.

[0065] In order to measure the phase information of two parallel laser beams, in the embodiment of the present application, the detector 140 may also 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 foregoing, 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 the light intensity information can be processed into the three-dimensional arrival direction of the sound source according to a preset algorithm in the processor 150. Of course, it should be noted that the deflection information and the 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 wave 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, and is specifically described in detail as follows.

[0069] See also Figure 4 When the laser emits a laser, it first passes through the beam splitter 1 to split a laser beam into two laser beams, corresponding to the measuring arm (i.e., the first parallel laser) and the reference arm (the second parallel laser). The measuring arm will be deflected and the phase will change due to the influence of the sound field emitted by the sound source. The deflection will be recorded by the PSD (position sensitive detector, i.e., the first detector), and the detection path is that the first parallel laser passes through the beam splitter 2 and reaches the PSD after passing through the sound field. 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 downwardly deflected and 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, i.e., 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. 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, the deflection information is related to the X-axis component and the Y-axis component in the direction of the sound source, and the phase information is related to the Z-axis component in the direction of the sound source.

[0070] It can be seen that, through the three-dimensional wave direction measurement system provided above, the laser is divided into two parallel laser beams by the beam splitter 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 phase information of the two parallel laser beams can be determined by the detector to detect the light intensity information of the light beam after interference, so that 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, so as to realize 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 aforementioned Figure 1 to Figure 4 The provided three-dimensional wave direction of arrival measurement system further provides a specific implementation process of a three-dimensional wave direction of arrival measurement method. Of course, in order to facilitate understanding that the measurement method provided in the embodiment of the present application can be used to achieve the measurement of the three-dimensional wave direction of arrival, the following first combines the relevant technical principles to explain the derivation process, which is described in detail as follows.

[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 schemes we can get:

[0078] x(t)=kk1L·sinc(kk3L / 2)e-jωt

[0079] y(t)=kk2L·sinc(kk3L / 2)e-jωt

[0080] Among them, x(t) can be understood as the function of the change of the transverse deflection information over time when the detection plane of the detector is regarded as the XOY plane, and the corresponding y(t) is the function of the change of the longitudinal deflection information over time. In addition, L is the effective distance of the acoustic and optical action, that is, the length of the reference arm affected by the sound 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 wave arrival direction [k1, k2, k3] of the sound source can be determined by the aforementioned measured quantities x(t), y(t), z(t). Figure 5 , 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. Specifically, the method is mainly applied to a three-dimensional direction of arrival measurement system of a 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, and dividing the emitted laser into a first parallel laser and a second parallel laser via a beam splitting component.

[0088] In the embodiment of the present application, when the laser generating device emits laser, it will divide 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 divides 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 to make the second parallel laser and the first parallel laser passing through the sound field to be measured produce an interference effect, and using a second detector to collect light intensity information of the interfered light beam.

[0092] In the 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, the interference component will further be used to make the second parallel laser and the first parallel laser passing through the sound field to be measured produce an interference effect, so as to modulate the phase change information of the first parallel laser passing through the sound field to be measured onto 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 known 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 schematic flow chart of a step of obtaining a three-dimensional direction of arrival based on deflection information and light intensity information provided in an embodiment of the present application, specifically, comprising steps S610 to S620:

[0096] S610: Demodulate 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 passing through the sound field to be measured relative to the second parallel laser can be obtained by demodulation and recovery, 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 passing through the sound field to be measured relative to the second parallel laser 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 formula provided above, it can be known 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 to say, 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 wave arrival direction 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 wave arrival direction 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] Among them, the definitions of various parameters in the above formula 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 the present application refers to a unit direction vector in a preset Cartesian coordinate system, wherein 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 arrival direction of a sound field. A laser is divided into two parallel laser beams by a beam splitter 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 by a detector. Based on the acousto-optic effect, the three-dimensional arrival 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 arrival direction of the sound field.

[0116] Of course, in order to realize the measurement process of the above-mentioned three-dimensional wave direction measurement, in a feasible implementation scheme, an electronic device is also provided, which is electrically connected to different components of the three-dimensional wave direction measurement system of the sound field, such as a laser generating device, a first detector and a 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 wave direction of the sound source based on the calculation process of the three-dimensional wave direction measurement method provided by the present 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, and the computer program composed of each program module enables the electronic device to execute the steps in 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 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 the computer program in the non-volatile storage medium. The network interface of the electronic device is used to communicate with an external electronic device via a network connection. When the computer program is executed by the processor, a three-dimensional wave arrival direction measurement method of a sound source is implemented, 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 beam 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 the 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 light beam after the interference; 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 merely a block diagram of a partial structure related to the scheme of the present application, and does not constitute a limitation on the electronic device to which the scheme 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 arrangement of components.

[0123] In some embodiments of the present application, a computer-readable storage medium is provided, storing a computer program, and the computer program is loaded by a processor, so that the processor executes any method 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 beam 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 the 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 light beam after the interference; 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 of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed 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 may 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, according to the idea of ​​the present invention, there will be changes in the specific implementation method 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 is used to split the laser light emitted by the laser generating device into at least two parallel laser beams; the parallel laser light includes a first parallel laser light and a second parallel laser light; wherein a sound field to be measured exists on a first optical path of the first parallel laser light, so that the first parallel laser light is deflected after passing through the sound field to be measured; An interference component, used for causing the first parallel laser and the second parallel laser that pass through the sound field to be measured to produce an interference effect, and obtaining an interfered light beam; A detection assembly, comprising a first detector and a second detector, wherein a 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 the three-dimensional wave arrival direction of the sound field to be measured.

2. The system according to claim 1, characterized in that The first detector is a position sensitive detector, and the second detector is a photodiode.

3. The system according to claim 1, characterized in that The beam splitter assembly comprises 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, characterized in that 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 that passes 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 that passes 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 that passes through the polarization beam splitter to form an interfered light beam.

5. A method for measuring a three-dimensional direction of arrival of a sound field, characterized in that: Applied in the three-dimensional direction of arrival measurement system of the sound field as claimed in any one of claims 1 to 4, the method 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 beam 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 light beam after the interference; 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 comprises: 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; The 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 comprises: Obtaining a first-dimensional wave arrival direction 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 wave arrival direction 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 wave arrival direction of the sound field to be measured, x(t) is the function of the change of the lateral deflection information over time, 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 passing through the sound field to be measured relative to the second parallel laser light comprises: 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, wherein the preset Cartesian coordinate system takes the detection plane of the first detector as the XOY plane, and the Z axis is perpendicular to the detection plane.

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